# Lord of the waves, The Two Towers, a 25 driver line array



## Wesayso

I was browsing the web with some questions about comb filtering and found Roger Russell's website. This page in particular: Why be so overly concerned about comb filtering in column speakers when you probably get this all the time with the speakers y

Because I'm still in the market for new speakers I was atracted by his story on line array's especially the IDS-25 line array. In my living room such an array would work out great as it can be placed quite close to the walls and use very little space compared to my 15" wover current speakers.
My girlfriend keeps nagging me to replace them with smaller ones. After I showed her the IDS-25 she gave me the "OK" to try and build some.
















I've found the original article from Roger Russell about these speakers and their 4" x 20 predecessors and am intregued. See attached pdf.
If anyone wants it I'll upload the pdf of the 4" version too.

Would it be possible to build a line array (same size) as the IDS-25 using the Vifa TC9FD18-08 drivers? I'd use a behringer DEQ24/96 for the time beeing to do the EQ part.

The part I'm worried about is the high Qts of these compared to the original driver Roger used in his array. Would that create problems? When searching for Vifa TC9FD18-08 it seems there used to be a lower (0.7) Qts version. Frequency responce seems very much alike. However this is a paper cone compared to glass fibre in the real thing. (Viva TG9FSD10-08 http://www.tymphany.com/files/resources/dvifa/TG9FSD10-08.pdf)
I'd like some schooled opinions on this if possible.


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## thehatedguy

The fact the "article" starts off with a red herring should give you a clue as to where it is heading.

He offers no proof that it doesn't happen.


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## Wesayso

thehatedguy said:


> The fact the "article" starts off with a red herring should give you a clue as to where it is heading.
> 
> He offers no proof that it doesn't happen.


He doesn't, he states it does happen but doesn't have that much of an impact. He compares it to seeing movies as a fluent motion if in fact it is a series of still images.

But I was looking for some input on an affordable driver for such a line array speaker.

Here's another design: The Murphy Corner-Line-Array Home Page

This one uses the Dayton Audio ND90-8.

Another candidate for an array might be the Tangband W3-1053SC 3":
http://www.parts-express.com/pdf/264-880s.pdf

But I was wondering if the Vifa TC9FD18-08 would be a better choise because of the Copper pole piece cap to limit distortion same as in the driver Roger Russell used.
See specs here: http://www.tymphany.com/files/TC9FD-18-08%20Rev1_0.pdf


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## thehatedguy

How we see movies isn't the same as we hear music.

Rather than taking his word for it, I would like to see a couple of measurements to support the claims.

And you would need to sit a long way away from the speakers to get anywhere near flatish response from them.


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## Wesayso

Did you download the attached pdf? It has measurements after EQ on page 9. If you look at the The Murphy Corner-Line-Array Home Page link above you'll many more graphs from a similar system both before and after equalisation.
I've read a lot on this subject over the past week, both positive and negative. One fun thread was about the IDS-25, where almost everyone was pissing on this design until someone came forward who had actually heard these in a motel room. So how far did they have to be from these speakers to get good sound?
I will not deny comb filtering will be an issue, however reading up on the personal experiences from people who have heard these seems to indicate they do sound great.

I have no way of knowing what I'll get myself into. But these designs seem to fit the bill for me, that is, if I can find a suitable driver for a decent price.

On most forums I have found that discus this particular design, there is a huge amount of prejudice without ever hearing them.

Some things are hard to imagine though, Russel claims the total cone area is bigger than one 16" woofer. Sure it is, but where's the excursion? So in the end the system will be somewhat limited in bass output I guess. But there's no way for me to be sure about that (yet). Reading up on the other example I profided: The Murphy Corner-Line-Array Test Results



MCLA array said:


> As a low frequency stress test I tried to drive the array to 10% distortion at 50 Hz. This is one measure of the maximum operating level of a speaker in the low bass range. Figure 5-13 shows the array operating at the highest level I could generate before the everything in the room started vibrating loudly. The system reached 113 dB SPL at 50 Hz with 65 Watts of drive level (18.7 Vrms into 5.33 Ohms). The dominant distortion is 2nd harmonic at -26 dB or 5% distortion. The 3rd harmonic is at -29 dB or 3.5%. The 5th harmonic was only at -48 dB or 0.4%. This is excellent high SPL low bass performance! A single array can drive the ROOM to the limit of what it can take with just 65 Watts at 50 Hz. At the highest levels a person (or room) can stand (113 dB SPL in this case) the distortion does not exceed 5% at 50 Hz.


So that's not bad at all. The low distortion I believe, think about how little these full rangers have to do because there are 50 of them in total...

I do hope I'll get some usefull help, I'd like to dive in and experience this for myself. It's a big risk on my part, but I was bored listening to most commercial speakers in the $ 1500 -2000 setprices in the shops I have been to and the ones that seemed promissing where no easyer to place in a room than my current set with 15" woofers. They all need to be placed away from the wall etc... and none of them have a footprint as small as these.

Reading the track record of Mr. R Russell: http://www.roger-russell.com/columns/columns.htm convinced me he knows way more about speakers than I ever will in my life. I know most in this business will say what they made is the greatest thing on the planet but what did he have to gain when he published the plans for the IDS-25 in an audio magazine for everyone to copy. That is the same set one can buy for more than $ 18.000,00 today.

Similar to the Linkwitz Orion, you can buy the plans or buy ready made versions. But Roger Russell published the plans without making money (I asume). With todays internet those plans are readilly available and attached to this thread . 

I am intregued to be able to build $ 18.000,00 speakers for a lot less. If I can figure everything out, that is.


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## Wesayso

Here are the spec's from an italian site stating the Qts of 0.72 as does Parts Express on their main site:
http://www.audiokit.it/itaeng/Altoparlanti/VIFA/TC9FD-18-08.pdf
Parts Express: http://www.parts-express.com/pe/showdetl.cfm?Partnumber=264-1062
If you click the PDF on Parts Express you get the specs stating Qts 0.95
http://www.parts-express.com/pdf/264-1062s.pdf

Same as with these specs from the Tymphany site (Qts 0.95)
TC9FD-18-08 | Tymphany

So are there 2 versions of this driver?


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## Wesayso

To answer my own question, the versions in Europe, or at least Germany seem to be different. They even have different names for what seems to be the same driver.

I modelled both the original IDS driver and the cheaper Peerless/Vifa and although there are important differences in specs the output of the cheap driver comes very close, about 5 Hz behind in the bass region. One thing holding me back is Xmax.
I had seen this as 3mm on several sites but it is 1.5 mm linear xmax and max xmech (?) is 3mm. That's where the more expensive driver shines in comparison with 2.35mm. So max output of the cheaper ones is going to be more limited I guess. But due to the line array gain it still might be more than worth it to try.

But to dare it I'd like to know how much Mr. Russel had to boost the lows. If he bumped it by 9 dB, the bump would take 16 watt, but that's only 16/25 = 0.64 watt for each driver in the column! It would require some serious amps if it is boosted any higer to crank it up though. Mr. russell claims 250 watt/channel to have headroom. If it's only a 6 dB boost in his setup I'd be willing to try the cheaper drivers. There are some graphs but it's impossible to read something on that.

It's comming down to just under 12 euro/driver or cough up 29 euro/driver for the unshielded version of the IDS with the 2.35mm xmax. Mr. Russell only used shielded drivers. I haven't seen those for sale anywhere.

I'm willing to take a risk on a line array and it's troubles with combing due to driver spacing. I'm not sure though I'd want to do that with 50x 29 euro worth of drivers...


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## thehatedguy

1450 Euro is a pretty big chunk of change for an experiment.

Does Monacor or Visaton not have anything less expensive that would give you a good idea on the flavoring?


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## Wesayso

Well, after searching for a suitible cheap replacement driver I stumbled over this post:
Stupid Cheap Line Array - Page 4 - diyAudio
He did exactly what I was thinking about. Same driver, same DEQ. So I guess it seems possible with these drivers after all.
I think it's time to built something or shut up


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## Wesayso

Ordered the TC9 drivers... I guess I'll find out if this works...
It will take me quite a while to build though. I'll try and put something up when I'm done.


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## Wesayso

Almost ready to work on this project again. Bought a lot of the needed hardware and made some plans.
My cabinet plans look like this but are open to change as I have not cut anything yet:








The plan was to buit this from 18mm and 12mm MDF in a (very) big stack.
The 12mm would be used for bracing and the 18mm for the actual chambers.
Stacking gives me the opertunity to make a round shape on the outside, helping with the WAF (GAF in my case ) and limiting difraction while the inner cavity could be made up with a wavy shape to limit standing waves.















The four holes around the circumfence are used for dowels while the bottom stack used threaded rods to connect to the footplate.
The inner parts would get a round over but because I want to water cut these parts I haven't drawn that. 
As a backup plan if water cutting is too expencive I have a friend who is willing to CNC these for me.

The outer shape would get a layer of fibreglass bonded to it to strengthen and smooth it out. The plan is to mount the drivers with the frame touching and fill in the sides to the outer box to have them close to flush.

Still have doubts about the MDF though. The thickness is not very stable and could be a problem when stacking this many layers. One of the reasons I haven't cut any yet. I'll look into a proper grade multiplex to see if that does any better. 

Zaph has recently tested the vifa drivers I bought for this project. See:
Zaph|Audio look for Vifa TC9FD18-08
Distortion plot
Not bad at all! Now imagine 25 of those per side.... that would drop the distortion even lower. I'm starting to believe in this project! (of coarse I do, bought the drivers, the EQ and some other random stuff needed)


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## generalkorrd

Wesayso said:


> Almost ready to work on this project again. Bought a lot of the needed hardware and made some plans.
> My cabinet plans look like this but are open to change as I have not cut anything yet:
> 
> 
> 
> 
> 
> 
> 
> 
> The plan was to buit this from 18mm and 12mm MDF in a (very) big stack.
> The 12mm would be used for bracing and the 18mm for the actual chambers.
> Stacking gives me the opertunity to make a round shape on the outside, helping with the WAF (GAF in my case ) and limiting difraction while the inner cavity could be made up with a wavy shape to limit standing waves.
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> The four holes around the circumfence are used for dowels while the bottom stack used threaded rods to connect to the footplate.
> The inner parts would get a round over but because I want to water cut these parts I haven't drawn that.
> As a backup plan if water cutting is too expencive I have a friend who is willing to CNC these for me.
> 
> The outer shape would get a layer of fibreglass bonded to it to strengthen and smooth it out. The plan is to mount the drivers with the frame touching and fill in the sides to the outer box to have them close to flush.
> 
> Still have doubts about the MDF though. The thickness is not very stable and could be a problem when stacking this many layers. One of the reasons I haven't cut any yet. I'll look into a proper grade multiplex to see if that does any better.
> 
> Zaph has recently tested the vifa drivers I bought for this project. See:
> Zaph|Audio look for Vifa TC9FD18-08
> Distortion plot
> Not bad at all! Now imagine 25 of those per side.... that would drop the distortion even lower. I'm starting to believe in this project! (of coarse I do, bought the drivers, the EQ and some other random stuff needed)


Seems like a fun project! I have some questions about the build process. Water cutting I think would be ultra BAD, have you seen what happens to mdf when it gets wet? CNC is the way to go with this. I wouldnt worry about the thickness of each piece, as the variation is usually less than a mm per pice. Since you are going to fiberglass anyway, you can make up any height differences at that point, I would imagine it wouldnt be any more that a cm total. Also, since you are curving the chambers, you dont need the pattern on the inside, as the curving itself takes care of any possible standing waves anyway. Also, that will cost an arm and a leg in wood and be very heavy... if you are going to fiberglass anyway, why not build the whole thing out of 'glass, your back will thank you for it. Just build a stick frame with a wood baffle, and fglass the rest. It wil be plenty strong enough to contain the massive bass pulses from those 3 inch drivers! Just some thoughts. Also, you may want to look at porting that setup, I don't know if them being sealed will give you the bass you seem to want- unless of course you have a sub, then it's a moot point.


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## Wesayso

Water cutting seems to be a good option with MDF according to some water jet cutting firms over here. It puzzles me as well. I think I will move to BB ply. It varies less in thickness than MDF with moisture differences. It will also be lighter. According to my CAD program the wood alone for one speaker will be about 30 KG.
I chose this method to have a rigid enclosure. A friend of mine steered me to fibreglass or Epoxy as well. I have thought about it but it has different problems to solve when I do. I'd probably opt for each driver in a seperate enclosure if I do.
For now I'm sticking to the stack of BB ply. There is another reason why I made the inner part that shape. The enclosure gets thicker and thinner in different places and I guess that could help me in resonances at little extra cost. The outer shape would help prevent diffaction.
Believe it or not, 25 of those little drivers are capable of bass extention way down to about 25 HZ! Together they have the radiating area of a driver bigger than a 15" cone but obviously limited by their induvidual 3.55 mm xmax. After playing with my current speakers with 15" bass drivers and observing their movement I start to believe in this concept. That's what the EQ is for, boosting the low end. Simulation proved it should be possible and much easyer, it has been done with the exact combo I have in mind.
See the link in post 9 above.

Came across the Anthony Gallo Reference 5LS today, fun to see similarities 







vs









He uses 12 little woofers for bass extention, in my case all 25 are doing that job. 
He has tweeters to help the upper end but the spacing is not better than the 25 woofers I'm planning (about the same in possible comb filter problems). 
Both are crossover free (exept the low end of the Gallo).
His may have better diffraction control but I'll do the best I can.
My project uses DSP to get there while his can do without. 
My budget is much lower (lol)
He designed his own, I borrowed the bigger part from Roger Russel  and gave it my own little twist.


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## generalkorrd

Wesayso said:


> Water cutting seems to be a good option with MDF according to some water jet cutting firms over here. It puzzles me as well. I think I will move to BB ply. It varies less in thickness than MDF with moisture differences. It will also be lighter. According to my CAD program the wood alone for one speaker will be about 30 KG.
> I chose this method to have a rigid enclosure. A friend of mine steered me to fibreglass or Epoxy as well. I have thought about it but it has different problems to solve when I do. I'd probably opt for each driver in a seperate enclosure if I do.
> For now I'm sticking to the stack of BB ply. There is another reason why I made the inner part that shape. The enclosure gets thicker and thinner in different places and I guess that could help me in resonances at little extra cost. The outer shape would help prevent diffaction.
> Believe it or not, 25 of those little drivers are capable of bass extention way down to about 25 HZ! Together they have the radiating area of a driver bigger than a 15" cone but obviously limited by their induvidual 3.55 mm xmax. After playing with my current speakers with 15" bass drivers and observing their movement I start to believe in this concept. That's what the EQ is for, boosting the low end. Simulation proved it should be possible and much easyer, it has been done with the exact combo I have in mind.
> See the link in post 9 above.
> 
> Came across the Anthony Gallo Reference 5LS today, fun to see similarities
> 
> 
> 
> 
> 
> 
> 
> vs
> 
> 
> 
> 
> 
> 
> 
> 
> 
> He uses 12 little woofers for bass extention, in my case all 25 are doing that job.
> He has tweeters to help the upper end but the spacing is not better than the 25 woofers I'm planning (about the same in possible comb filter problems).
> Both are crossover free (exept the low end of the Gallo).
> His may have better diffraction control but I'll do the best I can.
> My project uses DSP to get there while his can do without.
> My budget is much lower (lol)
> He designed his own, I borrowed the bigger part from Roger Russel  and gave it my own little twist.


I thought that a bunch of little drivers would do the same job as a big driver as well. Here is what I did:
I had an Ascendant Audio Havoc 18 sitting in 4 cubic feet sealed @ 1500watts in my old suv. Sold the suv, went to a king cab Dodge Dakota. Wanted that windshield flexing bass I had from that 18 (30mm xmax!). Bought 8 Image Dynamics 8's @ 1200 watts total, which have a healthy 15mm xmax each. 8 8's equals to almost 3 15's. Didnt work out quite the way I wanted. It sounds great, dont get that wrong, but it doesnt have the extreme low end that my single 18 did. My point is, there is no way that you will get "room shaking bass" from a bunch of 3 inch drivers. While they may play to 25 hz on a meter, I can guarantee you wont HEAR 25 hz the same as with even a single 15. That setup may very well get good and punchy(60hz on up), but low end..? NO. if you want to have a skinny speaker and get room shaking bass, look into a tall, deep tower with subs sunk into the sides... similar to my latest DIY build:








thats 4 8's on front, a 3inch dome mid and a 1 inch dome tweet, with a 15 inch passive sub on the side. 

granted mine are HUGE and extreme, but thats what I wanted. In your case, look at maybe 10 of your 3 inchers on front with a 12 inch sub in the side. That would be kinda nice, especially with a CNC on hand to shape the cabs( I didnt have one available).

Just my .02 from my experiences


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## subwoofery

generalkorrd said:


> I thought that a bunch of little drivers would do the same job as a big driver as well. Here is what I did:
> I had an Ascendant Audio Havoc 18 sitting in 4 cubic feet sealed @ 1500watts in my old suv. Sold the suv, went to a king cab Dodge Dakota. Wanted that windshield flexing bass I had from that 18 (30mm xmax!). Bought 8 Image Dynamics 8's @ 1200 watts total, which have a healthy 15mm xmax each. 8 8's equals to almost 3 15's. Didnt work out quite the way I wanted. It sounds great, dont get that wrong, but it doesnt have the extreme low end that my single 18 did. My point is, there is no way that you will get "room shaking bass" from a bunch of 3 inch drivers. While they may play to 25 hz on a meter, I can guarantee you wont HEAR 25 hz the same as with even a single 15. That setup may very well get good and punchy(60hz on up), but low end..? NO. if you want to have a skinny speaker and get room shaking bass, look into a tall, deep tower with subs sunk into the sides... similar to my latest DIY build:
> 
> 
> 
> 
> 
> 
> 
> 
> thats 4 8's on front, a 3inch dome mid and a 1 inch dome tweet, with a 15 inch passive sub on the side.
> 
> granted mine are HUGE and extreme, but thats what I wanted. In your case, look at maybe 10 of your 3 inchers on front with a 12 inch sub in the side. That would be kinda nice, especially with a CNC on hand to shape the cabs( I didnt have one available).
> 
> Just my .02 from my experiences


Is your room 25cuft or much bigger? Getting bass in a car and bass @ home is not the same. In the car you have to account for cabin gain which helps getting more SPL out of your sub whereas in your house, you won't get much. Try your 8x8" in your car and I can tell you it will rape your single 15 in low end reproduction. 

Low frequencies are reproduced with air moving, doesn't matter if you need 1000 2" drivers to equal the cone area of 1 x 18", if *vd* is the same, it "can" output as much SPL as that single 18". 

Kelvin


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## generalkorrd

subwoofery said:


> Is your room 25cuft or much bigger? Getting bass in a car and bass @ home is not the same. In the car you have to account for cabin gain which helps getting more SPL out of your sub whereas in your house, you won't get much. Try your 8x8" in your car and I can tell you it will rape your single 15 in low end reproduction.
> 
> Low frequencies are reproduced with air moving, doesn't matter if you need 1000 2" drivers to equal the cone area of 1 x 18", if *vd* is the same, it "can" output as much SPL as that single 18".
> 
> Kelvin


I dont think you understand what I was saying. I had an 18 in a car, was awesome at the lowest of lows. Replaced that with 8 8's, not so awesome at the lowest of lows. 

Also, I have read and heard that exact same thing, that all you need is cone area. Well, I DID the change from one huge woofer to 8 small ones, and supposedly GAINED cone area doing that, and LOST extreme low end performance. Oh, by the way, when I did the swap from 1 18 to 8 8's, I also reduced cabin size, so I increased cabin gain and STILL lost bottom end. The reduction from 1500 to 1200 watts is immaterial. So, you can stand by your theories, but I have seen it in action- it seems you need a big woofer to get to the stupid lows, house or car.


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## subwoofery

generalkorrd said:


> I dont think you understand what I was saying. I had an 18 in a car, was awesome at the lowest of lows. Replaced that with 8 8's, not so awesome at the lowest of lows.
> 
> Also, I have read and heard that exact same thing, that all you need is cone area. Well, I DID the change from one huge woofer to 8 small ones, and supposedly GAINED cone area doing that, and LOST extreme low end performance. Oh, by the way, when I did the swap from 1 18 to 8 8's, I also reduced cabin size, so I increased cabin gain and STILL lost bottom end. The reduction from 1500 to 1200 watts is immaterial. So, you can stand by your theories, but I have seen it in action- it seems you need a big woofer to get to the stupid lows, house or car.


The explanation is still easy to understand, the F3 was not the same between the 2 boxes. Do you know what was the F3 for the 8 x 8"? 
Having a box that is too small for the 8s" can contribute to more SPL in the upper register (50Hz+) which let's you perceive it as less low bass. Even if you had more SPL @ 30Hz, your ears would say otherwise since you have so much more pressure up top. 
Not saying you're wrong but there really is an easy explanation to what you experienced. Low freqs is air moving and nothing else. If it takes 1x8" with an Xmax of 30mm powered with 2000rms to put out the same SPL @30Hz as 1x18" with an Xmax of 5mm powered with 200rms - then so be it but the 8" WILL DO IT. It's not rocket science, just physics... 

Kelvin 

PS: sorry for OP for the OT.


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## generalkorrd

subwoofery said:


> The explanation is still easy to understand, the F3 was not the same between the 2 boxes. Do you know what was the F3 for the 8 x 8"?
> Having a box that is too small for the 8s" can contribute to more SPL in the upper register (50Hz+) which let's you perceive it as less low bass. Even if you had more SPL @ 30Hz, your ears would say otherwise since you have so much more pressure up top.
> Not saying you're wrong but there really is an easy explanation to what you experienced. Low freqs is air moving and nothing else. If it takes 1x8" with an Xmax of 30mm powered with 2000rms to put out the same SPL @30Hz as 1x18" with an Xmax of 5mm powered with 200rms - then so be it but the 8" WILL DO IT. It's not rocket science, just physics...
> 
> Kelvin
> 
> PS: sorry for OP for the OT.


You can believe what you like, but the meter isnt wrong. Yes the box for the 8 8's is built to the smallest sealed box recced(.25 cu per sub min[2 cu ft total]-.35 is reccd), the 18 was also in a box that was a tiny bit too small ( 4 cubes was recced, 3.8 final). That sub hit 141.7 legal @ ~45hz, with it hitting [email protected] 20 hz. The 8 8's cant get past 138 outlaw at any freq, and barely breaks 130 @ 20 hz. Thats alot more cone area, with about half the xmax. I wish you had the subs to be able to do the experiment yourself, but most people dont have an 18 AND 8 8's laying around to just experiment with.

Here, spec it yourself:
Ascendantaudio.com
http://www.imagedynamicsusa.net/pdf/subwoofers/id/id8d4v3_sepcs.pdf

8 inch sd= 231 cm sq.... x8 = 1848 total sd
18 inch sd=1210 cm sq. 
1.5 times the cone area with half the xmax but 1/4 of the low end performance.... something wonky there.


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## Wesayso

Well I'm basing some of my hopes on this article:
IDS: The Return of Roger Russell | Stereophile.com

I wouldn't be surpriced if you could feel the bass from 2x 15" woofers better than from 50x 3.5". I have read about people mentioning "audiophile bass", where you hear it but don't feel it as much. Still seems strange as it's moving the same amount of air? Maybe the multiple small speakers react less with room nodes as in Geddes example of using more than one sub?


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## generalkorrd

Wesayso said:


> Well I'm basing some of my hopes on this article:
> IDS: The Return of Roger Russell | Stereophile.com
> 
> I wouldn't be surpriced if you could feel the bass from 2x 15" woofers better than from 50x 3.5". I have read about people mentioning "audiophile bass", where you hear it but don't feel it as much. Still seems strange as it's moving the same amount of air? Maybe the multiple small speakers react less with room nodes as in Geddes example of using more than one sub?


Its hard to say for me why it's different, subwoofery is right about the theory of it. But every time I replace a big sub with a bunch of small ones, I lose a lot of lowend. In the case of my car, I traded 20-50hz bass from the 18 for 40-90 hz bass with the 8's. Dont get me wrong, I still have bass all the way down but it is not nearly visceral as it is with that 18. I just wanted to give you a different point of view from actual experience than just throwing math at the problem. Maybe there is a mathematical reason why the difference is what it is, and we just havent found it yet.


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## Wesayso

Well, Mr. Roger Russell's idea is based on boosting the low end so doing that wouldn't get you a measured difference. I bet you could apply that theory to the multiple 8" without reaching xmax. It takes more power though and at those low notes it adds up quick.
Mr. Russel boosts the low end by more than 15 db. That takes up power quick. But if you realise it gets consumed by 50 woofers it's not that much for each speaker. It does need the amps to back it up.
It's kinda like the Linkwitz transform. ESP - The Linkwitz Transform Circuit
So that makes two famous names in the audio world that don't mind boosting the low end. Are your 8" sub enclosures sealed? I'd say boost the low end and see if the feeling is the same.  
I've plotted the 50 drivers I intend to use and they should be able to do what I want. There is allready someone on diyaudio.com that did want I intended to do and he's happy. 
I figure I'll give it a shot first and if I'm not pleased I can always add an active sub. (probably a sealed one with linkwitz transform, lol)

This quote from the linked page is interesting:


ESP - The Linkwitz Transform Circuit said:


> Power Distribution (by Gareth Abrey)
> I was in the process of building a Linkwitz Transform cct for my 305mm (12") sub. ESP said in the articles about ELF and EAS that low frequency content in music has much lower power levels than the power calculations would suggest. I decided to investigate this, and digitised some tracks off various CDs with various styles of music.
> 
> My sound editor gives the WAVE graph amplitude in 16bits (-32000 to 32000). I then performed a low pass filter of 40hz on the track and found the highest peaks, then compared them to the highest peaks of the full range signal, and did a dB calculation ...
> 
> 20 log ( V ) (where V is the 16bit amplitude)
> Typically, I got (digital) peaks of +/-30,000 for the full range signal, and only +/-4,000 for the < 40hz signal. This is a 17.5dB difference. The results are tabulated below.
> 
> Music Type Relative Level at <40Hz
> Rock music - 13dB
> Maria Carey Song - 15dB
> 
> Rap Music - 14dB
> R&B song - 12dB
> Rave track - 12dB
> Second Rave Track - 21dB
> Vinyl Bass Track - 11dB
> Rave track with bass sweep - 9 dB
> Average - 11.875 dB (12dB)
> 
> 
> These figures would suggest that boosts of around 10-12dB are possible with the Linkwitz circuit, before any extra amplifier power is needed above that which is required for the frequencies above 40hz.


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## generalkorrd

Sad thing is, I dont have the eq available to boost my lows below 60 hz. Also, that 1200 watt amp I have pushing them is pretty maxed as it is now( at high volumes). I would have to double my power to see a benefit from boosting the eq. IOW, a lot more money than I have available to throw at my system again.


----------



## subwoofery

generalkorrd said:


> You can believe what you like, but the meter isnt wrong. It's not about what I believe, it's just simple physics - please read my below post... Yes the box for the 8 8's is built to the smallest sealed box recced(.25 cu per sub min[2 cu ft total]-.35 is reccd), the 18 was also in a box that was a tiny bit too small ( 4 cubes was recced, 3.8 final). That sub hit 141.7 legal @ ~45hz, with it hitting [email protected] 20 hz. The 8 8's cant get past 138 outlaw at any freq, and barely breaks 130 @ 20 hz. Thats alot more cone area, with about half the xmax. I wish you had the subs to be able to do the experiment yourself, but most people dont have an 18 AND 8 8's laying around to just experiment with.
> 
> Here, spec it yourself:
> Ascendantaudio.com
> http://www.imagedynamicsusa.net/pdf/subwoofers/id/id8d4v3_sepcs.pdf
> 
> 8 inch sd= 231 cm sq.... x8 = 1848 total sd
> 18 inch sd=1210 cm sq.
> 1.5 times the cone area with half the xmax but 1/4 of the low end performance.... something wonky there.


If you read my previous post I stated the following: 


> The explanation is still easy to understand, the F3 was not the same between the 2 boxes. Do you know what was the F3 for the 8 x 8"?


Here's how both of your box modelled: 








^ please note the F3 of your Havoc (46.85Hz) and the F3 of the 8xID8s (66.55Hz) 
THAT is the reason why you still had more output down low with 1x18" VS 8x8"... 

Now here's how 8x8" would compare to your single Havoc when both F3 are close enough: 








^ Notice now how the 8x8" have more output @20Hz than the single 18"? 
Please note that in the both pics, the Havoc is getting 1500 watts and the ID8s are getting 1200 watts. 

The only "fair" way to compare 2 things as apple VS apple is to keep some variables in check - comparing 2 subs, you can either try to keep enclosure size the same and see which sub models better for your application, or keep F3 the same to see which one produces more SPL. 

Here, if we were using the same amount of wattage, the 8xID8s would clearly win in SPL. Bass is easy to reproduce, move as much air as possible - doesn't matter if you need 1000 drivers to match the output of a single 21" ; low freqs is just that, air being moved  In a car, it's even easier since we have cabin gain... 

Kelvin


----------



## Wesayso

Picking this project up again... slight redesign so I decided to do some extra modeling:








This way I can make sure everything will fit and it looks cute .


----------



## Wesayso

Doing some more work on how I want to mount my baffle and be able to "service" the speakers I came up with this:








Not finished yet but it shows the basic idea. I'll probably put a rubber O-ring underneath the countersunk bolt and add a groove for it to lay in in the baffle. The square nut will get some extention to bolt to the layer of multiplex it's in to prevent rotating.

I'm hoping to make the baffle of aluminum as a sandwich with MLV in between where the speakers mount. They will be clamped between the two aluminum baffles and bolted to the inner ones.

Way to complicated but fun non the less. A bit like Magico meets Mr. Russel (lol).

A view from behind:


----------



## Wesayso

Final design...








Time to start building. Have some drawings ready for Water Yet Cutting, hopefully this week.


----------



## Wesayso

I got my water yet cut templates and feet back and have a big stack of BB/BB quality Baltic Birch ready to be cut. Now all I need is time...

When stacking the multi ply I'm still wondering if I should use wooden dowels to align my 4 holes in the stack or long threaded rods straight trough the whole speaker. I plan to seal the ply with epoxy, would it still expand/contract much after that?


----------



## Wesayso

First steps, a lot of work ahead:








On the left a finished set of routed ply, on the right the rough cut and my water yet cut template..
My DIY table (Workmate with a router between the vice, bolted to a piece of plywood) works. You can see a small stud behind the cutting bit to make it easier to start cutting by easing in using that stud.


----------



## chad1376

Wow - I just found this build. This is a first class project. I'll be back to check in on progress.

While I'm here, I thought I'd join as a member of the line array club. Here's my garage arrays, built with about $200 of PE buyouts. They're bi-amped using a mini dsp and a couple beater amps. Comb filtering??? Heck, I don't care, but I can hear my tunes over the noise of my air compressor pump and table saw.


----------



## Wesayso

chad1376 said:


> Wow - I just found this build. This is a first class project. I'll be back to check in on progress.
> 
> While I'm here, I thought I'd join as a member of the line array club. Here's my garage arrays, built with about $200 of PE buyouts. They're bi-amped using a mini dsp and a couple beater amps. Comb filtering??? Heck, I don't care, but I can hear my tunes over the noise of my air compressor pump and table saw.


How does it sound?  Big?
Thanks for the compliment!


----------



## chad1376

Well..Sound quality on a bunch of $4 woofers and $2 tweeters isn't any better than just a pair, but I get a lot "more". The speakers are technically flat down to about 50hz, but I really need a big subwoofer (or 4) to fill in the bottom. One significanly noticeable aspect of the array, is that each speaker is handling such a small portion of the load, that the sound effortless and never "compressed", up to the limits of the amps. Also, as you know, spl falls off at 3db, rather than 6db. This is awsome when I want to listen to music in my driveway, about 30'-50' away from the speakers. The biggest thing I want is more power. I'm running a beat up Adcom GFA 545II for the woofers, but I have my eyes open for a cheap pro-sound 1000 watt amp, so I can really push these and see what they'll do.

I was looking at your idea for using dowels or threaded rod to line up your stacked "slices". I recently built a layered construction for a subwoofer, using cnc cut mdf. I tried using 1/4 aluminum dowels for alignment. I found the tolerances in the wood made it very difficult to easily slide the wood over the dowels after about 4 pieces. I went to 1/4" threaded rod, which is slightly smaller in diameter. The threads would still catch the wood, but I could use a drill, and literally screw the dowels in at each stage of gluing. This worked well for clamping, but tolerances still did not ensure a perfect alignment of the pieces.


----------



## req

awesome project. i am very curious to see the assembly of this. i approve of the birch vs mdf


----------



## Wesayso

chad1376 said:


> Well..Sound quality on a bunch of $4 woofers and $2 tweeters isn't any better than just a pair, but I get a lot "more". The speakers are technically flat down to about 50hz, but I really need a big subwoofer (or 4) to fill in the bottom. One significanly noticeable aspect of the array, is that each speaker is handling such a small portion of the load, that the sound effortless and never "compressed", up to the limits of the amps. Also, as you know, spl falls off at 3db, rather than 6db. This is awsome when I want to listen to music in my driveway, about 30'-50' away from the speakers. The biggest thing I want is more power. I'm running a beat up Adcom GFA 545II for the woofers, but I have my eyes open for a cheap pro-sound 1000 watt amp, so I can really push these and see what they'll do.
> 
> I was looking at your idea for using dowels or threaded rod to line up your stacked "slices". I recently built a layered construction for a subwoofer, using cnc cut mdf. I tried using 1/4 aluminum dowels for alignment. I found the tolerances in the wood made it very difficult to easily slide the wood over the dowels after about 4 pieces. I went to 1/4" threaded rod, which is slightly smaller in diameter. The threads would still catch the wood, but I could use a drill, and literally screw the dowels in at each stage of gluing. This worked well for clamping, but tolerances still did not ensure a perfect alignment of the pieces.


Thanks for the feedback about the threaded rods. I think I'm going that route. The line up probably isn't going to be perfect but I'm planning to coat it with epoxy and paint when done. Good looking sub box you got there... Did it work well? It does take some extra material to construct it like that.
Was it worth it with the varying thickness of the walls?

I had a minor setback today. My cheap Rockwell router quit on me after just 2 weeks of work. I'm not near what I have to do, it came with 2 years warranty but I got my money back and I'll try a 4x more expensive Makita next. It's more powerful, with 1850 watt and should have no problem cutting these.

The Vifa's I am putting in this array do sound quite good on their own so I can expect the line array to sound as good but with way more volume .
I know the centre to centre spacing of the speakers in my array isn't ideal but from what I've read in patents and research by Macintosh it isn't a problem in the near field as long as the line array is long enough. The beauty is that the research was done when Roger Russel already had left the firm.
Time will tell but I am in contact with two others that have built similar arrays (though not stacked like mine) with the same drivers and both claim they are the best speakers they have heard.

I planned to put up a new picture showing the speaker chambers but that will have to wait.

I'm still wondering what to do with damping, I'd like to line the inside with felt but wool felt is way too expensive. I already have Twaron angel hair for damping the chambers (finer fibers than sheep wool) but like to line the walls with something. Maybe something like under floor 6mm felt?


----------



## chad1376

Wesayso said:


> .. Good looking sub box you got there... Did it work well? It does take some extra material to construct it like that.
> Was it worth it with the varying thickness of the walls?


Unfortunately, I haven't fired it up yet. I'm still working on the rest of my system, so It's still awaiting the install.

By epoxy and paint, are you planning like automotive urethane primer color and clear?

Just based on my experience, one thing to watch out for would be dimensional changes to the wood as is soaks up the paint. I had the ends of my "slices" sanded perfect with the DA sander, but the MDF soaked up the paint, and now I can see each of the laminations through the finish. I'd suggest, after the first prime coat, let the paint really cure and let the wood stabilize (like a week). Then give it another final sand to take up any changes that might occur.


----------



## generalkorrd

chad1376 said:


> Just based on my experience, one thing to watch out for would be dimensional changes to the wood as is soaks up the paint. I had the ends of my "slices" sanded perfect with the DA sander, but the MDF soaked up the paint, and now I can see each of the laminations through the finish. I'd suggest, after the first prime coat, let the paint really cure and let the wood stabilize (like a week). Then give it another final sand to take up any changes that might occur.


I would think that birch wouldn't react the way that mdf does. I know mdf will soak up any fluid you put on it and swell like... well, it will swell lol.


----------



## Wesayso

generalkorrd said:


> I would think that birch wouldn't react the way that mdf does. I know mdf will soak up any fluid you put on it and swell like... well, it will swell lol.


 lol


----------



## Wesayso

chad1376 said:


> Unfortunately, I haven't fired it up yet. I'm still working on the rest of my system, so It's still awaiting the install.
> 
> By epoxy and paint, are you planning like automotive urethane primer color and clear?
> 
> Just based on my experience, one thing to watch out for would be dimensional changes to the wood as is soaks up the paint. I had the ends of my "slices" sanded perfect with the DA sander, but the MDF soaked up the paint, and now I can see each of the laminations through the finish. I'd suggest, after the first prime coat, let the paint really cure and let the wood stabilize (like a week). Then give it another final sand to take up any changes that might occur.


I will use epoxy to seal, then prime and coat much like they do on boats. All that to prevent further soak up of moisture. But I will let it cure for a week before paint for paint just to be sure.


----------



## miniSQ

Wesayso said:


> Thanks for the feedback about the threaded rods. I think I'm going that route. The line up probably isn't going to be perfect but I'm planning to coat it with epoxy and paint when done. Good looking sub box you got there... Did it work well? It does take some extra material to construct it like that.
> Was it worth it with the varying thickness of the walls?
> 
> I had a minor setback today. My cheap Rockwell router quit on me after just 2 weeks of work. I'm not near what I have to do, it came with 2 years warranty but I got my money back and I'll try a 4x more expensive Makita next. It's more powerful, with 1850 watt and should have no problem cutting these.
> 
> The Vifa's I am putting in this array do sound quite good on their own so I can expect the line array to sound as good but with way more volume .
> I know the centre to centre spacing of the speakers in my array isn't ideal but from what I've read in patents and research by Macintosh it isn't a problem in the near field as long as the line array is long enough. The beauty is that the research was done when Roger Russel already had left the firm.
> Time will tell but I am in contact with two others that have built similar arrays (though not stacked like mine) with the same drivers and both claim they are the best speakers they have heard.
> 
> I planned to put up a new picture showing the speaker chambers but that will have to wait.
> 
> I'm still wondering what to do with damping, I'd like to line the inside with felt but wool felt is way too expensive. I already have Twaron angel hair for damping the chambers (finer fibers than sheep wool) but like to line the walls with something. Maybe something like under floor 6mm felt?


super awesome build here..so glad i clicked into see whats going down.

For damping the insides..for my swan diva 6.1's..( similar design only much shorter ) i used some butyl rubber dampener i bought from sonic electronics for the walls. And this wool blended product i got from MCM electronics.
Acoustic Dampening Pad | LS00916 | Distributed By MCM


----------



## Wesayso

miniSQ said:


> super awesome build here..so glad i clicked into see whats going down.
> 
> For damping the insides..for my swan diva 6.1's..( similar design only much shorter ) i used some butyl rubber dampener i bought from sonic electronics for the walls. And this wool blended product i got from MCM electronics.
> Acoustic Dampening Pad | LS00916 | Distributed By MCM


Thanks for the suggestions! My new router is up and running so I can resume my work. For the walls I am thinking of the felt material (the chamber is already a stiff construction with varying thickness from 18 mm to 25 mm and I'll connect the top and bottom of each chamber with 12 mm round wooden dowels to further increase the rigidness trough bracing.
It was after I put up a few pictures of my 3D model on diyaudio.com that a member there pointed to the similarities of my build with the Magico Mini's.
If you look at this:








You can see the lining on the walls. I was thinking of doing something similar to that. Troels Gravesen uses wool felt but that gets expensive fast.
I have thought of using a rubbery undercoat material for cars on the walls. I've done the spray can version in my sub box but the kind you put on with a brush would be even better I guess. I used some of it on my car not long ago and immediately thought of using it in this project. That would be somewhat similar to the butyl rubber. But I guess diffusion and absorption is what I am after, especially around the drivers. The butyl and undercoating would do more good in damping the walls than help absorb the back wave.

For the chamber itself I am going for this: TWARON Angel Hair, the new and innovative damping material for loudspeaker systems am room acoustic adjustments









P.S. I was looking at those Swan Diva's before I decided to built some speakers. That model wasn't for sale here in Europe so I haven't heard them. From all that I read about them they were interesting though.


----------



## Wesayso

Some progress at last..









A view of the chamber:









The new router is working great, I just have to keep things in motion.
It is on full power all the time at 22000 RPM so if I stop I burn the wood .
I was in doubt when I bought it as it was the only model without an electrical RPM switch but didn't want to spent even more money for the bigger brother that has a RPM switch or go for the lower powered one that also has such a switch. The last router claimed 1250 watt but I doubt it had much power on the router bit. This one is 1850 watt and has much better bearings.
1850 Watt is useful though, it cuts through the ply wood like butter. Just have to keep it in motion.


----------



## chad1376

I'm digging the internal alternating phase sinesoidal diffusers (you're gonna have to pay me royalties if you want to use that term in any promotional literature).


----------



## Wesayso

Just to show I'm still at it;


----------



## req

that thing looks awesome dude. i cant wait to hear what you think about all that work!


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## Wesayso

Well I can tell you what I think about all that work right now: :hanged:

You got to be a little crazy to do this all by hand with a jigsaw and a router.
Lucky for me I am that crazy.
I just hope it pays off in the end.

P.S. I found some genuine wool felt material in 5mm thickness that I think I'll be using on the cabinet walls. The rubber undercoating I mentioned was asphalt based and as such a no go.
I couldn't find a butyl based rubber coating material. I don't think I'll need much extra damping due to the construction of my cabinets. I'll dampen the 15 mm layers that go between the speakers by gluing a vertical wooden dowel between them with an elastic glue/kit. Don't want that rigid, I read some interesting papers from Steen Duelund where he mentioned a construction similar to what B&W uses with bracing with holes like this:








Steen agreed with that vision but said you'd want to decouple the braces from the outer speakers with elastic damping glue (isopunkt).


----------



## chad1376

I love this build - keep rockin' the router. Hopefully it doesn't make you so deaf at the end that you can't appreciate your work.


----------



## Wesayso

chad1376 said:


> I love this build - keep rockin' the router. Hopefully it doesn't make you so deaf at the end that you can't appreciate your work.


I do wear protection to save what I have left .

Here's a size reference:








_(my almost 7 year old posing beside the stack)_

This thing is starting to look intimidating size wise. Still 7 more chambers to go!
Seeing as I am going to coat the outside with epoxy, should I seal the inside too? And with what...


----------



## Wesayso

I think I'm going to answer my own question. I'm going to coat the inside with Por 15 clear. It's almost the same as epoxy as far as sealing but a lot more practical in use while gluing the stack.
Here's the loose stack of ply as big as it gets:


----------



## chad1376

..awsome beyond words..


----------



## alm001

Yesssssssssssssssssssssssssssssssssssssssssssss. That is beautiful.

This is on my to-do list for a future HT build.
I love line arrays, and I love stacked wood enclosures. I did one a while back for a subwoofer, but I made it too difficult with cavities for concrete, and lots of failure points. Never got to making a version 2.

























https://plus.google.com/u/0/photos/101495155964528224533/albums/5361624673248583745

I've also got a partial tweeter array in my car.

Great work so far.


----------



## Wesayso

Nice sub build! Reminds me a bit of this one here: 21" Maelstrom Curved Box Build









What went wrong with it? I didn't dare use mdf stacked this high. I would be afraid of the temperature and moisture changes of the air making it swell/contract. I'm hoping sealing everything with epoxy will further save me from that.


----------



## alm001

Wesayso said:


> Nice sub build!...
> 
> ...What went wrong with it?


Thanks,

A number of things went wrong;
Problem 1 was the cavities... the walls were very thin so the contact area for glue wasn't huge.
Problem 2 was the concrete. I used concrete dust. Couple that with 38 seams that CAN fail, and some will.
Problem 3 was sealing the thing, all those MDF edges would suck up all the epoxy I threw at it.
Problem 4 was the weight. Yes, I wanted it heavy - when I had my jeep. In any other car a 120+lbs enclosure isn't a great idea.

If I were to do it again, I would use different wood, maybe ditch the cavities
(if I kept the cavities, I would fill with clay or something)

The sub is gone, but when this thing was first put together it was absolutely incredible. I had never felt bass like this before - and I was pretty pissed that I went so long in a sealed box.


----------



## alm001

I can't even imagine doing this by hand.


----------



## Wesayso

alm001 said:


> I can't even imagine doing this by hand.


Me neither .

Good to hear that story about your sub though. I'm still trying to determine the necessary steps to make a big stack like this work. Maybe even wrap some cloth around it?
I hope it isn't needed though, it's enough work as is.


----------



## kronos

Did anyone notice that he said there was 10dB of acoustic gain at low and mid frequencies for the column compared to a single driver? That means 1/10th of the power is needed for the same acoustic output. This is a welcome bonus for the low frequencies.


----------



## Wesayso

Yes, I'm counting on that .


----------



## alm001

Wesayso said:


> Yes, I'm counting on that .


Any progress?


----------



## Wesayso

At the glue stage right now...


----------



## alm001

Looks like you are using threaded rod, and bolting each layer down to clamp as you glue? Not a bad idea.


----------



## Wesayso

alm001 said:


> Looks like you are using threaded rod, and bolting each layer down to clamp as you glue? Not a bad idea.


That's the idea, yes... The threaded rod will become a part of the speaker.
It was the easiest way to align and clamp I could think off. The rod is damped by an elastic glue/adhesive every other layer.
Here's the tool I made to drill the holes for the bolts that will hold the baffle:


----------



## quietfly

AWESOME build...


----------



## Wesayso

quietfly said:


> AWESOME build...


Thanks!


----------



## chad1376

I'm happy to see more progress - this is still one of the coolest builds I've ever seen. keep the pictures coming!

I have what is probably a worthless thought - but maybe worth considering. With so many stacked peices, I wonder if it would be beneficial to use a torque wrench to ensure all the threaded rods are under the same tension at each stage of glue-up. I could see uneven tension possibly compressing one side more than the other, and giving the stack some unwanted camber.


----------



## Wesayso

Thanks for that thought, I did think about that idea but only use a level to check.
I used that level before to setup the aluminium strip you see and the stand. I glued the stand to the floor ensuring it was level and bolted the aluminium strip down.
Not much room for error is left that way but I still check the stack every now and then with the level.
The straps you see also function to keep things in line as I use a spacer that keeps the aluminium strip about a millimetre outside of the baffle opening so I can tie it down..

A stack like this sure takes up a lot of time to complete...
Can't wait to start sanding it all smooth (lol). That 'll be fun!


----------



## Wesayso

Getting there... first speaker is glued and roughly sanded in shape...









Standing free on it's own, the wooden array measures 2225 mm high .


----------



## chad1376

Either the speaker got taller, or your kid got shorter  I hope you don't like in an earthquake prone area.


----------



## Wesayso

He's standing on his toes .
Last picture with him was ~ 7 or so chambers shorter..

No quakes here to speak of. I think they weigh about 45 kg as is. With the baffles and speakers etc it will be a bit more!


----------



## Wesayso

One is up, one more to go...








_(in the right corner you see the "tool" I made for my drill to keep me sane while turning the nuts)_


----------



## alm001

Wesayso said:


> One is up, one more to go...
> _(in the right corner you see the "tool" I made for my drill to keep me sane while turning the nuts)_


I was wondering about that. No way would I have the patience to spin those down.

Looking great. I am very excited for this build to come together.


----------



## pjc

As a fellow work worker I'm speechless. Your dedication (craziness) is unbelievable. I'm loving it.


----------



## Wesayso

pjc said:


> As a fellow work worker I'm speechless. Your dedication (craziness) is unbelievable. I'm loving it.


I'll gladly admit, you have to be more than a little crazy to do it like this with hand tools...


----------



## Wesayso

alm001 said:


> I was wondering about that. No way would I have the patience to spin those down.
> 
> Looking great. I am very excited for this build to come together.


Spinning them up or down was a 20 minute job. The drill reduced that to 2 minutes .

Thanks for the kind words.


----------



## Wesayso

Test fitting the baffle:








Between the aluminium are 2 layers of 3.7 mm MLV. One layer will go under the
thickest aluminium plate and one between (as thick as the basket mounting area)

Cross section will show the idea somewhat:


----------



## alm001

I'm compelled to come to your garage, and watch real-time as these come to life.


----------



## Wesayso

alm001 said:


> I'm compelled to come to your garage, and watch real-time as these come to life.


That could turn out to be a long stay! 









More info here: The making of: The Two Towers


----------



## chad1376

alm001 said:


> I'm compelled to come to your garage, and watch real-time as these come to life.




I'll bring the beer, and dole out worthless suggestions from the sidelines.


----------



## Wesayso

Where were you guys, I'm kinda thirsty after a day of sanding .


----------



## Wesayso

Slowly getting there:


----------



## Wesayso

Two towers sanded, almost ready for the finish...


----------



## its_bacon12

Good luck man - pretty ambitious build. I suggest you going to techtalk at Parts-Express and posthing this stuff there. Lots of good and smart people there to help with this stuff. 

I'd also like to point out you need to chamfer the back side of the baffle for each driver hole to let the mid breathe; otherwise you get a tinny, closed in sounding mid.


----------



## Wesayso

its_bacon12 said:


> Good luck man - pretty ambitious build. I suggest you going to techtalk at Parts-Express and posthing this stuff there. Lots of good and smart people there to help with this stuff.
> 
> I'd also like to point out you need to chamfer the back side of the baffle for each driver hole to let the mid breathe; otherwise you get a tinny, closed in sounding mid.


Thanks!

I'm also on diyaudio.com with this project so pretty much covered on the technical side for my questions etc. The beauty of my baffle plans with aluminum is the lesser thickness required for the same stiffness as wood and it will be chamfered.








_(the open spaces in this drawing will be filled with MLV around the speaker basket and between baffle and the enclosure)_


----------



## Wesayso

On my way to apply the finish:








Third coat of PU lacquer shortly after applying...

Temporary paint booth:


----------



## alm001

Beautiful!


----------



## MLS

They look great! Patiently waiting to see a few more detailed pics.


----------



## Woosey

Wow gaaf!!

Great job man!

chapeau!!


----------



## Wesayso

Preliminary paint results:

















Still have to work on some small spots and sand and polish. But I'm quite pleased so far!
6 coats in total...


----------



## fast94tracer

Wow just beautiful! 

Sent from my SCH-I605 using Tapatalk 4


----------



## Niebur3

Absolutely beautiful. What color is that?


----------



## Wesayso

Baltic birch with 2x a nitro based Old antique cbm221 stain and 6 coats of PU clear.


----------



## n_olympios

Am I the only one unable to see the pics??


----------



## Wesayso

n_olympios said:


> Am I the only one unable to see the pics??


Does this help you?


----------



## n_olympios

Yes, very. Thank you!


----------



## req

JEEZ >_<


----------



## Wesayso

In the past couple of days I tried to finish the paint, a little polishing etc.








_Left one untouched, right one is polished_









_Hard to take a picture of such a slippery finish_









_I think this one comes closest to seeing the result_

Still not done with them. Sadly I went trough the finish in 2 places 
I'll see if I can restore that a bit. I haven't done something like this before so it's a learning curve....

The mounting feet look like this now:


----------



## knever3

Wow, love it!


----------



## alm001

Have you powered these up yet? How's the progress?


----------



## Wesayso

Not powered up yet...

I parked the speaker enclosures in the house to let them breath for a while.








The first two weeks nothing much happened as I observed the dimensions of the speaker (expecting a little contraction due to difference in humidity and temperature.
But nothing prepared me for this:
















I always knew it could happen, but I had hoped to have enough pressure on the rods to prevent this. I was able to glue the stack back together. The night it happened it was a very rapid change in the weather outside. But come January the contraction will be even worse. 

I did get an awful lot of replies on DIYaudio.com to remove the rods to prevent further cracking. I get why I should do that but it doesn't fit well with my plans for the aluminum baffle.

A friend of mine will make the baffles for me, I dropped of the aluminum and am waiting for his schedule to clear to be able to make them. 
My idea is to let the enclosures do as they please for the coming winter (can't work in the non heated garage) while moving on with mounting the speakers. I will not permanently bond anything to the enclosures (yet) for the time being. 

In the spring I will decide what steps to take. It will probably be a laminate of epoxy with either glass fiber, Kevlar or carbon weave matt. Prior to that I'll make grooves in the stack to allow the wood to work. These grooves will be filled with some type of elastic material.

I'll loose my finish, so be it. I'll get a smooth black enclosure that won't react to humidity/temperature like this wood version does in return.
In the mean time I'll play with the speakers after the baffles are made but won't be fully able to bring up the low end as planned using EQ. It will crack again, I'm sure.

I moved on to making a test enclosure for testing the damping materials I'll use.









in other words: down, but not out yet .


----------



## n_olympios

The pics aren't showing. And when I try to open them in a different sheet, I get a 403 error.


----------



## Wesayso

n_olympios said:


> The pics aren't showing. And when I try to open them in a different sheet, I get a 403 error.


You had that before right? I'll upload them..


----------



## n_olympios

Yes I did and it seems it only happens on my work pc, so it's probably something on my end.


----------



## req

oh. my. god. :bigcry: 

they look crazy and amazing though.


----------



## alm001

Ouch, sorry to see the setback - but glad it hasn't put you out yet!


----------



## chad1376

OOOF! - I decided to check your progress, only to find this setback. I hope there wasn't a small kickable dog in the room when you first saw this.

Is it possible the rods expanded and helped to pull the layers apart? If so, I wonder what the differece in expansion cooefficient from the aluminum baffle would do. I like the idea of stress relief and bonding a strong skin on the outside. Carbon fiber weave could look awesome. Kevlar, though, would be a little stretchier I think. (I'm no materials engineer though). Don't give up on these!


----------



## Wesayso

The effects of the steel rods would be minimal, it's the wood that works... 
not much you can do to stop that...


----------



## luisc202

Wesayso said:


> Two towers sanded, almost ready for the finish...


Holly cow this is awesome man....


----------



## luisc202

n_olympios said:


> Yes I did and it seems it only happens on my work pc, so it's probably something on my end.


It's something on your pc because I see them fine .


----------



## roduk

Gutted for you re the cracking, but what a cracking pair of speakers they will be!! You can get a resin with carbon fibre in it rather than fibreglass which would probably be ideal to plug gaps when the time comes. I love the idea of building a pair of these sometime!!


----------



## Wesayso

Had a big break due to life getting in my way but wanted to tell you guys I'm still at work getting these things finished. My CNC deal fell trough so I had to find a way to make them myself. After trying with the router and wood cutting bits I kept destroying the roller bearings on the bits. So I came up with a solution:








And a bit closer zoom:









Here's the first two baffles:








A lot more needs to be done to them (on the back side) but this will do for my immediate next step, fixing the enclosures. I needed the baffles for that.
Don't expect me to be done in a few days yet . 
If I learned one thing from this project it is to be patient.
I'll have to sand down that nice finish I got to be able to get something useful. Too bad, but I'll pick up the original plan to have an epoxy/matt outer shell on them. Time will tell how that step goes. Sadly I'm running a bit behind my original schedule because my car (from 1982) was in need of repairs.
The car is fixed and running great again so I can go back to this project full force.

Glad the aluminium machining is now working well. That gives me the opportunity to make it just as I had planned. All done with simple wood tools so it will still take a lot of time


----------



## Wesayso

Here's a copy of what I just posted on DIYaudio.com, I'm already fixing the enclosures but sadly can't save the nice finish I had on them.

Well, where to start! After the success with the baffles it was time to fix the enclosures. Taking in mind all the advice I got here I had to make up my mind.
Most of the advice pointed out to get rid of the threaded rods, dedicated to save the nice wood finish I had achieved.
But the wood finish was a stray of my original plans. I just had to try it because the wooden stacks looked so good! But sadly it didn't work out so I went back to my original plan. That plan was epoxy plus a fibre glass weave mat. After thinking it trough a bit I figured the wooden stacks are always going to shrink and expand. That will continue to put a lot of pressure on the epoxy/mat laminate. About halfway in the story about the dreaded cracks I came to the conclusion if you want to build a stack this high, you've got to include a level of elasticity in that stack.

So the arrays went back in the garage and I immediately sanded down the finish to bare wood. That hurt! So I figured I should do it and be over with that.
After that I picked up a saw and started hacking up the enclosures in pieces(!)








Starting at the backside with a hand saw and a jig saw I cut 24 times, leaving the bottom one in tact.
Between the rods I drilled a few holes to fit the jig saw and cut the sides. The front was easy again with the jig saw.
I made sure to get about a 1.5 to 2mm cut all around. After that awful job I bolted on the baffle.








Some rings and nuts as spacers and in the speaker chambers I fit pieces of ply with the right dimension to keep about equal distance with the baffle to keep the enclosure straight.

I decided to seal the cut in the inner chamber with the same rubber glue I used to seal the rods in the stack. Then from the outside I poured in some DIY PU foam (water tight foam, 2 components, used in ships). The home brew foam is a bit different from the spray cans in the hardware stores. It is a closed cell foam.








I did the back and the sides, next unbolt the baffle to do the front.
After that step, bolt on the baffle again and hang the enclosure for epoxy work.
With some left over scraps I build a rig to hold the enclosure...








_(like a turkey above a fire )_


----------



## Wesayso

Having the enclosure in the rig it was time for epoxy. First soak the wood with epoxy for a better laminate bond with the cloth.








Working wet in wet I applied the cloth when the epoxy was still wet enough to leave a finger print. 
Then worked in the epoxy in the mat. Applied in a coat from the top down, and squeezing it out with a bondo spreader...








The cloth was cut oversized and I taped it at the bottom to the baffle (which had tape on it to protect it from the epoxy).
Took my time with the spreader to really squeeze the epoxy into the mat. Due to the weight of the overhang cloth I was afraid the cloth would separate from the enclosure at the baffle edge. I chickened out and after letting the epoxy gel a bit first I taped the entire enclosure with some household plastic wrap.
Didn't have enough time to tidy up this part of the job, so it left me a few wrinkles in the first layer. But at least it put pressure on the mat to let it cure to the edges. 
I stayed away from the garage the next day to prevent me from doing something foolish. It is after all my first time working with epoxy. This kind of thing is new to me .
I did rip off the plastic wrap after 24 hours of dry time and it looked promising.

The day after that, with at least 36 hours dry time I sanded the laminate, cut the overhang and took out the baffle and spacers from the chambers.








Not bad for the first try...

Next it was tile to fill in the mat with epoxy so I mixed up a batch of epoxy with micro balloons. Being the first time I had my mix wrong to I followed with a second coat wet in wet that evening. No pictures of that but it looked awful. I used a roller to spread it out and the thing was shedding off fluff(?) into the exterior. But it needed sanding anyway so with a finer grid sand paper on my random orbital sander it looked like this:








Starting to look half decent... 
I figured one more coat with micro balloons but something different to spread it out. I had already tried the spreaders for that job and didn't like it. I figured I wanted a "Duratex" like finish so I took a gamble and used 2K lacker rollers with the chance of it dissolving or burning up from the epoxy. Lucky for me it didn't. It left me with a very nice Duratex like finish. I think I'm going to keep it like that.








It was time for this enclosure to come of the rack anyway as the next one was ready for more of the same. That's where I am today:








The somewhat rough finish will get 2 coats of 2K PU in satin black but I can't sand it down. I want to keep that texture. 

A piano black finish was never in the cards and not wanted. The enclosure would have to be perfect for that to work. I'm running out of time due to it being fall and still have to finish the second one. But I don't want that kind of smooth finish anyway. For now I'll keep the aluminium blank. Still have to make the outer baffles but needed to finish this first. I'll polish them as I did the stands, they held up pretty good over a years period.

Still far from ready but getting there. Hopefully more to come soon!


----------



## Wesayso

Moving along...

















Final goal:


----------



## Weightless

Reminds me of this...


----------



## alm001

Very happy to see this back on track.


----------



## Hanatsu

Missed this. That's some seriously big line array. Really nice!


----------



## Babs

Oh you have so gotta play the theme from 2001 on those. 
Awesomeness with awesome sauce here man!
Great work!


----------



## GLN305

Behold....Speakerhenge! Beautiful work, loving it!


----------



## Wesayso

Next step, polishing the front baffle plate:


----------



## Beckerson1

Wesayso said:


> Next step, polishing the front baffle plate:


This keeps coming to mind:

"Honey the kids touched the speaker again."

Your reply

"Not again, I just polished it from the last time"


----------



## Wesayso

LOL, maybe I should put some high voltage on the aluminium? You know, like an electric fence


----------



## Beckerson1

Wesayso said:


> LOL, maybe I should put some high voltage on the aluminium? You know, like an electric fence


Lol... to messy


----------



## Wesayso

Finished polishing the first baffle. Figured I had to keep it somewhere safe so:








I like the look. At first I was afraid it would attack to much attention. But in the dark
it acts as a mirror and blends right in.


----------



## Hanatsu

That's crazy xD

Dunno if I missed it, what drivers are you gonna use?

Sent from my Samsung Galaxy S5 using Tapatalk


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## Wesayso

Vifa 3.5" fullrange TC9 FD 18-08 (x25)


----------



## Victor_inox

There is alu polish with sealer in it, will stay clean for very long time, I used in on my motorcycles polished parts.http://www.amazon.com/Wolfgang-MetallWerk-Concours-Metal-Sealant/dp/B004UQQA04


----------



## Weightless

Beautiful work. I love the black and polished aluminum. It matches the room its in. Too cool.


----------



## Hanatsu

Ah Tc9. Great drivers. I'm doing measurements on those sometime in the near futùre. 

Beautiful work indeed.

Sent from my Samsung Galaxy S5 using Tapatalk


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## JoshHefnerX

I wonder if putting these together dry stacking and putting them in the house for a couple of months would have helped some w/ the cracking also as the wood would have been more normalized in it's moisture content.

Josh


----------



## Wesayso

Well I can tell you my oak floor is still expanding/contracting. It has been in the house for 12 years now... So would that have been enough?


----------



## Wesayso

Victor_inox said:


> There is alu polish with sealer in it, will stay clean for very long time, I used in on my motorcycles polished parts.http://www.amazon.com/Wolfgang-MetallWerk-Concours-Metal-Sealant/dp/B004UQQA04


Thanks for that. I have a sealer for alu but don't know yet if it is any good. So I'll keep this link just in case.


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## JoshHefnerX

How much does the humidity level vary where you're at? I guess living in the desert as long as I have has been blessing from that point.


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## Wesayso

Well, outside it looks like this (average seasonal values):









But I guess it varies inside at a higher level due to heating etc in the winter season. I live in a house build in 1927 and as a result it is more susceptible to those problems.
At the time of the crack in my enclosures there was a sudden change in outside climate and temperature.


----------



## The A Train

So theres no tweeter array? Are you worried of high frequency lobing?


----------



## Wesayso

No worries here.... I already know what to expect and have no problems with that.
A tweeter array would have other compromises as all choices are compromises in a speaker build. 
The floor to ceiling length (well, at least more than 70% of ceiling height) array does a bit better in that regard than a shorter array would do. I have researched this problem before I started building them. There are some nice papers out there to support the need for a tweeter array but also those that support the contrary.
Testing my car setup with sine waves showed me I had combing problems in the car due to the many reflections you get there. Just move your head a little with test tones playing in a car. Some frequencies much worse than others of coarse. But I never notice it while playing music. These full rangers are packed close together to push the combing effects to the higher frequencies as much as possible. Main goal is no crossovers in the vocal range and high dynamics. This setup can manage those goals on as small a floor space as possible. If I didn't have a girlfriend (that I want to keep happy) I'd probably build a big horn setup (lol). I'm thankful she lets me build these .

_(By the way, when did this forum get inline links for words like Car and Build etc.)_


----------



## Wesayso

Temporary parking spot:









Working on the back baffles now, chamfering and drilling driver mounting holes.
Next up: testing damping materials with test enclosure seen beneath the TV.
Then on to wiring etc...


----------



## Wesayso

Working on the back baffles...


----------



## Beckerson1

Wesayso said:


> Temporary parking spot:
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Working on the back baffles now, chamfering and drilling driver mounting holes.
> Next up: testing damping materials with test enclosure seen beneath the TV.
> Then on to wiring etc...


Those make the TV look like a pebble.


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## Wesayso

It is... only 37"... smallest Panasonic Plasma at that time. Good picture quality though...


----------



## Hanatsu

I love Panasonic plasma. I've owned three of them now. Looks awesome 

Sent from my Samsung Galaxy S5 using Tapatalk


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## Wesayso

Working on the gasket behind the back baffle:








And on to lots of bolts and nuts, it really drove me nuts anyway 









Don't get too exited, just a test fit...
_Still a lot more work ahead_








_Nice comparison between old and new_








_Even with the epoxy/glass layer you still see the Birch ply coming trough_








_Should have cleaned the enclosure_ 









All in all pretty pleased with fit and finish. The polished baffle doesn't seem to
come trough as it takes on the colors of the environment. Or lack there off .


----------



## Weightless

That right there is diysexy.

Are you going to keep the hardware dark or replace with chrome?


----------



## Wesayso

My intention was black... Sadly with the alu baffles RVS would not be a good choice.
I might try zinc coated ones to see what it looks like. These bolts will get some paint on them. They are the least noble metal and as such prone to corrosion.


----------



## Wesayso

Second tower is almost complete too... 









I've been busy running impedance tests on my test speaker:









Rigged up a test wire for REW and ran some tests...









More results a few days later:








_Purple is driver on baffle without box, grey is box without stuffing)_

I think I'm gonna try some impedance measurements of my car door speakers as well.
Bubble wrap seems like a fun standing wave killer for that hostile environment. A 30+ year old car has leaky doors you know...


----------



## Wesayso

First one is up and running, second is not far away


----------



## Hanatsu

I'm in the middle of testing theee drivers. Data will be up soon 

Sent from my Samsung Galaxy S5 using Tapatalk


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## Wesayso

The TC9? Link me if you have results...


----------



## Hanatsu

Yeah. I'll measure them tomorrow, currently have them on "burn-in"

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----------



## Hanatsu

Here you go, Vifa TC9 full review:

http://www.diymobileaudio.com/forum/member-reviews-product-comparisons/170856-vifa-tc9-3-midrange-widebander-review-measurements.html#post2213351


----------



## Wesayso

No surprises there, except maybe top end extension. I've seen better (more extended)test plots in the higher region. In time I'll probably run some tests with 25 in a row.
The only way I know I have the one speaker that's ready playing loud is when I try to have a conversation. I suddenly have to shout but didn't notice it was that loud.
Very clear midrange (and the reason I went for it, after all, it's ALL about the midrange).


----------



## Hanatsu

Yeah. Midrange is impressive, I might do some other home audio design using these and XT25. Need to find a cheap and impressive midwoofer as well.

Sent from my Samsung Galaxy S5 using Tapatalk


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## ben54b

Great build. 


Sent from my iPhone using Tapatalk


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## Hanatsu

Again, awesome build!

I was inspired to build a mini-version of yours with a tweeter added to use as computer speakers. Bought 4 TC9 drivers and two waveguide XT19 (XT19NC30-04) drivers. Perhaps a LR2 filter at 4kHz.


----------



## Wesayso

Just got my second tower up and running... these little Vifa's are mighty impressive once you run 50 of them at once! Crystal clear sound!



Hanatsu said:


> Again, awesome build!
> 
> I was inspired to build a mini-version of yours with a tweeter added to use as computer speakers. Bought 4 TC9 drivers and two waveguide XT19 (XT19NC30-04) drivers. Perhaps a LR2 filter at 4kHz.


Not a bad idea to run a tweeter with 4 Vifa's. MTM? Should be fun!

Even when playing the towers pretty hard, I've not seen the cones move except on that "Lorde" song "Royals".
Yet you can feel the bass. Pretty hard to believe all of that is coming out those little speakers. But if you think of it,
if I feed them 100 Watt each, each cone/driver still only gets 4 watt(!).


----------



## Hanatsu

25x 36,3cm² = 907cm² 

Equivalent with a 15-16" driver / side. That's kinda amazing really.

It's gonna be a MTM yeah


----------



## Wesayso

Speakers are being run in during this last week:
















Tilted 15 degree inwards... I know there are 2 types of imaging. One where the musicians seem to be in the room with you and one where you are transported to the actual event. Close your eyes and these do that last version of imaging . Speakers disappear completely. Mission accomplished. And that's with a generic EQ curve applied. Still need to measure for final EQ.


----------



## HiloDB1

Absolutely stunning build. Interested to see your FR plot and EQ curves when you're done.


----------



## req

very cool. with all the setbacks from the cracking and fixing it is very cool to see this come to fruition. 

I wish I could have a listen.


----------



## Wesayso

HiloDB1 said:


> Absolutely stunning build. Interested to see your FR plot and EQ curves when you're done.


Thanks!

Here's the FR plot:









Impulse:









The EQ curve doing some crude pre-shaping:









After that it's DRC doing it's thing .
One thing to notice though, I use no boosting of high frequencies 
That came as quite a surprise for me.


----------



## Hanatsu

That looks like a well behaved ETC. The smooth and slightly falling FR is great in a moderately large room. I expect it sounds quite neutral and balanced. Amazing low end btw.

Sent from my Samsung Galaxy S5 using Tapatalk


----------



## Wesayso

Considering the plot was made at the listening position 3 meter away from the array in a normal living room... Only one damping panel 2.10m x 0.6m behind the curtain.









The noise floor is kind of high living in a busy street with cars passing by during these measurements.
Just switched from USB to Toslink on my DAC after these measurements, that dropped some noise in my signal (50 Hz hum from the power supply of my PC). I'll try to take some measurements at a higher level next time. The trouble is things begin to rattle around the room if I go up to high .
If I measure the lines without EQ it is not uncommon to see 110 dB level at the mid frequencies(!). That really shakes up the terrible steel ceiling I have (that I'm planning on replacing but I'm kind of scared what I'll find above it. original ceiling was plaster and straw).


----------



## Victor_inox

Seems to behave nicely, good looks just a benefit. dude you rock, job well done.


----------



## Wesayso

On my quest to even better sound I figured to hang a damping panel on the opposite wall to the arrays. I made a new design, loosely based on the poster I had hanging in that spot the last 14 years. The poster I replaced was getting old anyway and way at over 30 maybe even 40 years.








_(size is 1.05 m x 1.56 m or ~ 41.5" x 61.5")_

I'll add a third panel soon, this one pretty much did what I expected.
Printed at Spoonflower on Kona® Cotton: Premium Quilting... as this material was found to be very transparent to audio waves.
The third panel will be behind another curtain. But for those thinking about adding damping in their living room I can highly recommend Spoonflower.


----------



## ben54b

Thanks for the heads up on spoon flower. I have been thinking about something very similar using family photos. " look wife at how much I love my family" she won't even know that they are for the stereo. How have you framed it and what is it packed with. 


Sent from my iPad using Tapatalk


----------



## Wesayso

For this panel I used glass wool insulation with ~2" thickness. In my side wall application I use 3" thickness. It's hanging about half an inch from the wall, I couldn't do more without getting into trouble .

The inside frame is a simple wood frame (50 mm x 16 mm) with steel inserts in the corners. The outside picture frame you see isn't there yet. It's photo shopped to see how it would look.
I used a neoprene glue to hold the fabric in place, some nails at the back to keep it there but the glue holds up pretty good by itself.

I'll likely use some thin picture frame made of ~ 9 mm wood, painted in a way to make it look older to please the girlfriend who's into that sort of thing.


----------



## Wesayso

Still at the job of making these speakers sound stellar. I believe in time coherency as a factor to make a speaker sound believable. So that's why I'm messing with FIR filters to get there. Slowly but surely getting there, sound keeps on improving, sounding more real.

So on to a little experiment. I gathered all kinds of wires to test out differences. I even used solid core copper wire, normally used in my house for wiring my outputs...

Here's a frequency plot with my old wires, thick multi strand wire, 24 years old, restriped of coarse...








_note this is the result after convolution, generated minimum phase included as a reference_

After a few tests I went back in my garage and found some fairly new wire in my stash, I got it while buying a second hand Genesis Car audio amplifier. The seller included it in the package. It's looking much like generic wire with the difference that the core wires are very stiff. This performed very much like the solid core house electrical wire also tested. The result:








_Both plots are smoothed 1/12, gated at 5 ms and convoluted after a basic measurement
The acoustical phase being flat compared to the minimum phase is part of the FIR correction_

No change in the position of the array between these plots. I always thought the phase wraps were caused by reflections or diffraction. I guess there are measurable differences in cables after all.

Interesting huh? Too bad I couldn't find any Cat5 or 6 to test in my house. I should have it somewhere.

Here's the plot showing phase of the left channel in the first 5 ms zoomed back to 300 Hz:








_Measured at the listening position, gated 5ms, smoothed 1/3 oct, so that's what they mean with the phasy behaviour of line arrays ._


----------



## Cubdriver

Those look incredible!! What an amazing build!

-Pat


----------



## Wesayso

Thank you, Pat...


----------



## Wesayso

Still working on perfecting sound, here the left and right speaker measurements at the listening position:








Red is right channel, Blue is left channel, smoothing 1/12 octave.


----------



## Inferno333

Pretty damn flat if you ask me.


----------



## Wesayso

I haven't updated this thread in a while... have been busy though...

Left, Right and stereo signal:








_gated with a 4 cycle frequency dependant window_

Left and Right channel combined showing phase:








_again, gated with a 4 cycle frequency dependant window_

Group delay at listening spot:








_Smoothed 1/3 octave_

Spectrum plot -20 dB down Left + Right:









And I have some ambient channels running, diffused L-R, delayed, attenuated, band-passed etc. according to the lectures of Lycan/Werewolf. With some extra stuff from myself thrown in.

Like I said, I've been busy 
The wonderful powers of FIR correction at work here, DRC-FIR and some more.
Plus some old fashioned damping panels (as shown before), those helped to achieve this. Pretty content with the sound (big understatement ), after all, that was the goal!

It used to be: Car beats house. Not any more, not by a long shot! Learned a lot from this though. But some of it was from here, Lycan, can't thank you enough for the valuable lessons. For newer guys that stumble over this post. Look for user Lycan, and his former unregistered werewolf account. Read it all, it's worth it. That formed the basic principles for me to be able to do all of this.

So in hindsight, it's been well worth the trouble!


thehatedguy said:


> How we see movies isn't the same as we hear music.
> 
> Rather than taking his word for it, I would like to see a couple of measurements to support the claims.
> 
> And you would need to sit a long way away from the speakers to get anywhere near flatish response from them.


I think the measurements prove it was worth it.  Listening distance, between 2.5 - 3 meter. All measurements shown were taken at the listening spot. Comb filtering does exist. But it hasn't reared it's ugly head. It does show up in ungated raw measurements. Thankfully we don't hear like that!


----------



## Wesayso

*best wishes to all!*


----------



## Babs

Man those are awesome!


Sent from my iPad using Tapatalk


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## HiloDB1

Sooo much envy.....


----------



## Wesayso

After reading an interesting paper by Raimonds Skurul and reading the review thread by Hanatsu: http://www.diymobileaudio.com/forum/member-reviews-product-comparisons/171172-tda-time-domain-analysis-measurement-software-review.html
The paper can be found here: http://www.diyaudio.com/forums/full-range/284916-room-correction-speaker-correction-what-can-we-do-dsp-power-now-availabl.html

I decided to try out the demo version to see my timing results in higher resolution. After all, time coherency was my primary goal.
I was a bit scared to try as I've been working on this all trough last year. What if I didn't like what APL_TDA would/could show me?

Here's the left + right speaker, measured at the listening position, my own FIR correction, measured with APL_TDA measurement suite:









The 2D plot:









And the result when run without the FIR correction:









Pretty pleased with the outcome so far. I love the ease to see what's going on in these plots. I needed to look a lot harder in REW to see if I was getting close to anything useful. Yet the correction I use was created with REW, DRC-FIR, JRiver and a lot of patience and learning. This is not a forced DSP correction here that sounds awful off axis. It's actually a pretty short frequency dependant window, shorter than most presets that come with DRC-FIR. I forged my own template and settings based on a lot of testing (25 measurement sessions last time I looked) and even more virtual runs to find out what does what exactly. And of coarse trying to tie that to the listening experience.

One thing I can tell you. I enjoy listening to these immensely. I'd say all this work pays off in spades. The better my measurements became, the better sound I got. And a lot of hurdles on my way there... the old saying: two steps forward, one step back comes to mind describing that journey. 

To be continued, I'm sure...


----------



## Woosey

Wow, that looks great..


----------



## cubdenno

Beautiful job!! Great measurements! 

I miss reading Lycan/werewolf threads!! Though as before, a lot of what he said would ruffle a lot of pseudo science believers feathers.


----------



## Wesayso

cubdenno said:


> Beautiful job!! Great measurements!
> 
> I miss reading Lycan/werewolf threads!! Though as before, a lot of what he said would ruffle a lot of pseudo science believers feathers.


Thanks, it does sound very good too! After all what are all these pretty pictures worth if it didn't result in that! Going on my personal experience, this stuff really works.
And the beauty is move left to right or up and down and it stays the same unlike most multi-ways. I'm not listening to music. I'm listening to acoustical events. :laugh:

I got a lot of valuable lessons, reading Lycan/werewolf's stuff. Tried some of his ideas and kept it as it really works. I loved it that when people would ask him what he had in his car his answer was: nothing much or even none. He was here to teach. At least that's how I saw it. Good thing too as I was here to learn!


----------



## Wesayso

I've asked a friend of mine to do a review of my speakers. He's an avid music lover and in his spare time he's a musician and records and mixes his own music. He's used to hearing passages over and over again to make the right choices in his own mixing process. From our talks about music I know him to be at least as passionate about a musical experience as I am. Regularly going to live performances of his favourite Artists.
I've had more people come over and listen. But I wanted to get an honest review from someone that would be critical. For that you need to be passionate about it. I think I found the right person for the job and I promised to publish his piece as is. (whether I would like it or not )



Jan Fekkes said:


> Hi Ronald. Here is my report
> 
> 
> I will make apologies in advance for my English but I give it my best shot!
> 
> 
> ----He explained it all to me. The whole building process of his now grownup 7 ft twins. It is impressive, the way they gaze at me with each holding a long row of little speakers. I do not understand and comprehend everything Ronald told me about his project in a very enthusiastic way but I feel a lot of respect and admiration. Blood sweat and tears were shed to accomplish what is standing in front of me. “This is it, they produce sound and I think I did a good job” Well,….. a good job is a big understatement…because I have listened and they certainly produce sound. To call it just sound is way too simple to describe what is entering your ears. Tone colors is a better way to put it. Any color you like is there. Anyway, I was asked to give my honest and frank opinion about his tall and rank self-built stereo speaker set.
> 
> So, how do I do that? I asked myself. I don’t want it to become a lyrical piece of prose so people will doubt my honesty…..but I am lyrical. And that is because I am a critical listener, picking up details and can feel music to the bone. But anyway…at this my findings, while having a coffee on the ‘hotspot’ at Ronalds place.
> 
> 
> Opeth, Windowpane from the album Damnation. I immediately feel like I’m on very right spot in the concert hall. The ultimate place to be, everybody is always looking for, I am experiencing now. Every instrument is clearly in place and it is very extraordinary, I can almost feel the space in between. It is a wide sound with room for everything that is going on. There is prominent clarity but the bass and deeper tones are perfectly present without domination. Hearing and feeling them in a very pleasant way as if sound and air cooperate to make it just right. This is how it should be. Like putting on 3D glasses. The musical landscape gets an extra dimension. It is warm and deep and I can’t help it so say….”Holy macaroni” (which is an old Dutch saying meaning: ….I’m flabbergasted) This is some hearing experience!!
> 
> 
> Something completely different. He puts on the Sugababes. Hole in the head. It is not music I prefer but that is not the reason why I am sitting on the hotspot. So babes, let’s go J. I’m surprised that my ears tell me something different from my prejudgment. The extra dimension these speakers offer makes it very nice to listen to. While listening I made an image of a rectangle on my piece of paper. This rectangle is where this dominant kind of pumping song has its body. This was meant to be I guess…for the crowd….in your face…. But don’t get me wrong…everything is still on place and has its own distinctive position with clarity and warmth. And then there is out of the box… there is this nice tingling Ping-Pong panning effect which makes you happy… No other way to put it. It is hard to explain what makes these speakers so special but I think it has to do with a very nice wide stereo image without losing the natural reproduction. A sort of…the real thing!
> 
> 
> David Bowie, Ashes to Ashes. I will confine myself to the striking details now. That I am very enthusiastic about the speakers needs no further explanation. I now notice how many tracks have been used for vocals in this song. There is a upper stream and a undertow with vocals and bizarre effects. These speakers apparently do have the distinctive character to reveal these details.
> 
> 
> Blackfield – Blackfield. The clarity of the rhythm guitar is striking. Not that I couldn’t hear it on my own speaker set but over here, on the hotspot it comes more forward.
> 
> 
> Blackfield – Hello. In a way a little shocking to find out about the honesty of these speakers. The high frequencies that are floating above it all in this song are too dominant in my opinion, it is really hurting a bit. Too bad….but a honest message. Didn’t notice this before, at least not as strong as now, not in a way it disturbed me like now.
> 
> 
> Overall….
> 
> Like I said, I’m a devoted listener but not a technician. Don’t know about charts and measurements and why it should have this or that value. I know what I hear and I know it sounds great. Like I mentioned, I’m a critical listener but….. It was a revelation.
> 
> Ronald, for me, for what it is worth, you accomplished a great result. Thanks for being a little part of it!


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## Wesayso

Another review of my speakers:


Boden said:


> Last friday I paid a visit to Wesayso, not only to see and listen to the Two Towers, but also to familiarize myself with the REW, Jriver, DRC and Convolver FIR linearization procedure. Wesayso was most patient and helpful in his explanation.
> I have listened for about 30 minutes to the Two Towers, with some material I brought myself. I can say this is one of the most impressive loudspreakers I have listened to in a long time. Apart from detail and depth, for me one of the most striking and unexpected feature was the deep and completely effortless bass, which is amazing given the size of the drivers. But then again, cone surface/displacement matters. As the late John Wright of IMF/TDL advertised: “we rather move a lot of air little than little air a lot”. And so it is with the Towers
> Although the listening session was very brief, and I could not compare different approaches of digital equalizing, it was clear form the first notes something truly excptional has been achieved by Wesayso. The measurements of the Towers do not lie.
> Very very few system I have heard in the last 30 years come even close. Sometimes reproduction of the Towers is almost intimidating. Some 34 years ago I had a magnetostat line source system with 3 stacked Streathern units per side, which units were also used in ithe Infinity QRS at the time. The was certainly resemblance between these two -seemingly very different- systems. I never managed to properly integrate bass with my Streatherns, so finally I gave up. Wesayso has succeeded here: this is were i.m.h.o. the Two Towers excel. But only praising bass does not do justice to the rest of the reproduction including extra-ordinary transparance.
> Some may like to know whether this a “they are here” or a “you are there” system. I always struggle with this description, but I tend to say this a “you are there” system.
> For me, this system is an outstanding example of what can be achieved by very clear thinking and application of full blast DSP instead of the typical Hi End obsession with exotic drivers and electronics, but missing the basic requirements a la Toole and Geddes for a worldclass in-room loudspeaker system by far.
> What a job!
> 
> Eelco


I couldn't be more proud :blush:


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## Wesayso

A third review is in, a DIYaudio forum member made his way over from the states



xrk971 said:


> I was on a trip to NL for work and just got to visit Wesayso (and meet his beautiful family) and his Two Towers. A big bonus was Byrtt also came from DK to join us. What a great time we had between old friends meeting in person for the first time.
> 
> Thanks Wesayso for the hospitality and thanks Byrtt for driving a million miles from Denmark to meet us!
> 
> So what do the Two Towers sound like?
> 
> One word: Uneffingbeliveable.
> 
> Hands down the best speakers I have ever heard. Unrivaled by probably 99% of anything out there commercially or DIY.
> 
> Congratulations Wesayso on knocking this one out of the park! :cheers:
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> The most impressive thing about the Two Towers is the whole experience. It's not because any one aspect is good, it's because EVERY aspect is great. The large wide sweet spot, the force of the wall of sound, the low distortion, the accurate deep bass, the sweet smooth mods, the impeccable time alignment and transient perfect nature of the sound, the clear as a bell highs, the superb deep bass down to 17Hz (no subwoofer), the immense feeling of being teleported to the recording venue. It's all there and it all works together to produce what is perhaps, the closest feeling to being there I have felt when hearing speakers. Wesayso worked really hard on the SYSTEM approach so it includes room treatments, convolution processing, rear ambience speakers (10Fs), and careful adjustments.
> 
> The system makes any music sound it's best and there is no genre that doesn't sound its best.
> 
> Wonderful experience. World class!
> 
> Oh, the cabinets themselves are very impressive. I put my ear to the side while they were playing and could not hear or feel any vibrations or sound. Just inert. The hand cut and polished aluminum bezel waveguide is also quite the piece of workmanship.
> 
> Coffee at Wesayso's house is indeed quite an experience.


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## Wesayso

Still keeping these arrays in mint condition, I recently added some filtering to combat comb filtering (just to learn about the differences). I did not want to loose the dynamic character of full range arrays, so I came up with passive filters that create a frequency dependent roll off. Inspired by a fellow DIYaudio member (nc535 on DIYaudio.com) I started with Vituixcad modeling to see if there was something to gain. He was kind enough to share an array model which I adjusted to my own build. With some assistance I further improved the data to match what I have build.

Here's a model of an unfiltered array and it's filtered counterpart with added floor and ceiling reflections:








Easy to see the improvements in output. If the vertical window looks small it is good to remember you'd only need about 15 degree to cover sitting/standing. Obviously I've optimized the seated positions, but did not loose sight of the 'standing' results.

I've been remodeling in our living room so these arrays were parked in the garage for quite a while. That's when i added the filtering...








The top row is the filters for each group of the series parallel drivers (listening height center remains unfiltered).
The smaller bottom filters are notches used to get my center driver group at the right listening height. I rearranged the groups for that.

One caveat of storing the line arrays in the garage. Several drivers failed due to bad connections of the lead wires to the voice coil. They simply corroded beneath the glue and caused an open circuit. No less than 6 drivers out of 50 suffered this faith. While my garage is a bit damp or moist at times, I did not expect this to happen. The drivers were about 10 years old. 

I've thought long and hard about the next step. Do I simply replace all drivers (buying 50x TC9)
or is my trust in them broken. Long story short: I bought 56x Scanspeak 10F 8414G10! Currently I'm waiting on delivery, in the mean time I fixed the broken drivers and have music to enjoy.


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## Wesayso

I still haven't made a picture of the room in current conditions but here's a preview:









The arrays got a new final coat while being operated on. They are fresh to serve us for a long time to come, after getting all new drivers sometime soon.
The drivers themselves need some cutting to fit:








I made a fixture to get it repeatable:


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## Wesayso

Next up, the driver change... impatiently awaiting the arrival of the Scanspeak drivers...


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## MythosDreamLab

Yeow, I'm counting 25 speakers per column(?), very nice...!

I have a Home Theater set up as well and put a rug under my Subwoofer and over the wood floor to reduce the boominess of a hard reflection...


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## Wesayso

Both sub and array are resting on industrial damped feet.
All of it is adjusted with FIR filters, no boominess here .

The back channels are single driver Scanspeak 10F 8424G00's, they serve as ambience speakers while listening to stereo.
I absorb all early reflections, the ambience gives back what i stole from the room... it makes the space sound (much) larger than it is.


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## Wesayso

I found a little more time to really explain _why_ I have no boominess... Before I had subs, the line arrays ran full range and due to a little 'room enforcement' and lots of boost (up to 14 dB maximum boost, 25 drivers sharing that load) I could play down to 20 Hz. I used the strong points of each array and their output into the room. With FIR filters the phase was altered a bit to fit the array's minimum phase behavior and each array played louder where it was stronger for the really low notes.








_Left and right array channel balance before adding the subwoofers. Together it sums flat at the listening spot/area._

Meaning the left array did the heavy lifting at the bottom end, due to corner placement. But it had a null at ~70 Hz. I let the right array do the lifting there so basically below about 80 Hz I had flat bass output, but kind of a mono sum to get there. Yet it was pleasing and strong without the boominess.

After introducing the sub-woofers they each filled in the weak spots of the arrays. While I still let the arrays play low bass, but now at a much lower level (applying a low shelf of -9 dB at ~160 Hz to the above graph for the left and right channel) but they still help fill in the holes, working kind of like the multi sub solution as proposed by Geddes, but this time in stereo. The left sub together with the left array fill in each others problem area's and the same goes for the right side. All that is needed is differing lengths to walls and solid objects etc. creating refection points at differing intervals to be able to fill in the other's weak points. That's basically why it can work like that in low bass because it has these long wave lengths. 








_Look at the bottom scale, this is the timing as recorded at the listening spot of a stereo pair of arrays._


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## Wesayso




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## Gill

It will take some time to alter the frame? Do share your views on 10f vs TC9, everything else being constant.


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## Wesayso

Yes, that's going to take time. I'm doing it by hand, in a really old fashioned (but repeatable) way.



























it really isn't hard work, just tedious having to do it 50+ times .
But at least the amount of heat into the frame is kept at a minimum this way.
I'll take my time as it will probably be spring time before I will bring my arrays back into the garage to finish it up.


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## Niebur3

Too bad you didn’t buy the thiel scanspeak 10F that were on eBay a couple years ago.


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