# CSS LD25X Tweeter



## ErinH (Feb 14, 2007)

Info:
http://www.stereoclarity.com/products-page/brands/css-ld25x-tweeter/

2.83v/1m


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## ErinH (Feb 14, 2007)

High output at 102db @ 0.5m (97db @ 1m).


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## WLDock (Sep 27, 2005)

You plan to test these yourself? and maybe the mids? I wonder if they would lend you a set for testing? Was thinking of checking them out myself...Thinking about the $371 combo price: Creative Sound - Product Details

http://www.diymobileaudio.com/forum...vwr126x-xbl-mid-woofer-ld25x-xbl-tweeter.html

Man, does that tweet look nice!


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## ErinH (Feb 14, 2007)

Mid is sitting on my desk. it's up next. 


Sent from my iPhone. Pardon the grammar.


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## ItalynStylion (May 3, 2008)

WLDock said:


> You plan to test these yourself? and maybe the mids? I wonder if they would lend you a set for testing? Was thinking of checking them out myself...Thinking about the $371 combo price:


That reminds me, I need to get the combo price/offering up on my site as well. Thanks for the reminder!


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## WLDock (Sep 27, 2005)

bikinpunk said:


> Mid is sitting on my desk. it's up next.
> Sent from my iPhone. Pardon the grammar.


You are the man sir! I really want to hear these....was just thinking about them yesterday.


Walt


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## WLDock (Sep 27, 2005)

Yeah, that combo price is nice given the fact that I've been really thinking about the Scan 12m and Illum tweets. Really want to get more feedback on these but it's still early.

Sent from my HTC Sensation 4G using Tapatalk


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## ItalynStylion (May 3, 2008)

WLDock said:


> Yeah, that combo price is nice given the fact that I've been really thinking about the Scan 12m and Illum tweets. Really want to get more feedback on these but it's still early.
> 
> Sent from my HTC Sensation 4G using Tapatalk


I'm having trouble updating my website with a coupon code so I'm likely just going to build another page. Shoot me an pm/email if you're interested in the combo.


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## IBcivic (Jan 6, 2009)

Voyeur mode, on...


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## WLDock (Sep 27, 2005)

ItalynStylion said:


> I'm having trouble updating my website with a coupon code so I'm likely just going to build another page. Shoot me an pm/email if you're interested in the combo.


Will do!

Sent from my HTC Sensation 4G using Tapatalk


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## subwoofery (Nov 9, 2008)

Heh... Got the update from the DIYAudio forum  

Thanks Erin, 
Kelvin


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## ErinH (Feb 14, 2007)

the midrange is about 80% done with testing. 

3rd order distortion is top notch. 


data soon....


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## cvjoint (Mar 10, 2006)

Looks like this puppy can cross at 1.6khz without much headache. 1" midrange anyone? I wonder how well it will hold up against the deep chamber Scans.


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## WLDock (Sep 27, 2005)

Silly me... just realized that these are your measurements of the tweeter.


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## ErinH (Feb 14, 2007)

que?


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## cheebs (Apr 3, 2009)

anyone hear these yet? what do they sound like?


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## SSSnake (Mar 8, 2007)

Quit testing things that measure well  I just bought the scan tweets.


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## ousooner2 (Jan 6, 2011)

^ Maybe i'll take them off your hands...


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## cheebs (Apr 3, 2009)

any of u klipper testing guys finish testing these hand them over.


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## truth seeker (Nov 8, 2012)

There is a group buy of the LD25X occurring on DIYAudio. Go to this thread to post your interest:

Creative Sound Solutions: CSS LD25X - diyAudio


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## ErinH (Feb 14, 2007)

Thanks for the link. Someone on tech talk linked that and I've been considering picking up 3 for an LCR build. 

May post my data to help em out.


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## truth seeker (Nov 8, 2012)

I think you should post your data.


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## whoever (Nov 21, 2008)

shame these had QC issues


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## 2010hummerguy (Oct 7, 2009)

whoever said:


> shame these had QC issues


Good news, the new LD22 is less expensive, low distortion, similar excursion (good low end performance) and better off axis response.

Creative Sound - Product Details


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## RAW (Aug 11, 2005)

Ok I have been busy and finally got around to post you some info on the LD25X sinking ship.Yes these had a LARGE quality control issue from everything possible.The motors hand assembly issues and the faceplates as well.

First off a few were sold and sent out from CSS to people like Jeff B who designed speakers with them. As I did as well for CSS I designed the VX series using this tweeter.

AS most do I shot FR and designed the crossover did all tests assembled called it done.Listening sound good..

Well a week later I was doing a TM design for CSS using the MOTUS woofer in a TL single fold design which used a vale guide from Dave P. Dave had made 24 of these wave guides for the LD25X unassembled motor.After I did the design listened to them for a week assembled the crossovers took them to CSS for Bob to listen to.When I got them back a week later I measured one and the crossover had issues!!!! What 
So I took the speaker out of the room measured the other one and it was fine.At this point i started swapping crossovers etc. Then tweeters... There is was So I called Bob he brought me out 12 more to test.And every one I tested impedance was all over the map.

No way it could be that bad, must be my Praxis.We checked every other drive I had besides the tweeters with no issue with my Praxis Bob sent some drivers I tested to Dan. Dan tested them. Then the same drivers went to Mark K.Mark found the same results.

With this I then got every tweeter from CSS to test. And after I tested about 40 Bob new he had a BIG issue with the tweeters. And trying to make matched pairs was impossible.So I did impedance only on all the tweeter. (at some point my time and Bobs money call it quits) 









With all the testing done on the 300 plus tweeters i did I had the chore of picking pairs matching the impedance and FS only.This was a few days work I tell you. Some had FS low down at 750 some up at 3500. 

Here is some frequency responses taken with the tweeters on a 10" wide cabinet.All were taken within a few minutes of each other.









Now to the impedance


























































With this I said we have a small problem here Bob.

During all this we were working together to make a new tweeter with low distortion motor.A custom made faceplate which is made in Canada local to CSS.The new LD22 has 2 faceplates for the same motor a flat and a curved. Both have similar FR but differ in the upper octave off axis,and the presentation is different.

With the tweeter assembly at CSS Bob has control of the final production of his tweeters now.


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## cajunner (Apr 13, 2007)

does the LD22 have XBL gap in the motor?

for the LDX25, what would cause such extreme fluctuation in Fs and impedance, or it was never determined?

how low is the LD22 in average Fs, does it have a rear chamber and what is the output capability?


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## 2010hummerguy (Oct 7, 2009)

LD22 does not have the XBL motor but it does have comparable excursion.

I'll let Al comment about fs, rear chamber and output...I need to buy a pair to compare with my LD25X.


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## cajunner (Apr 13, 2007)

Architect7 said:


> LD22 does not have the XBL motor but it does have comparable excursion.
> 
> I'll let Al comment about fs, rear chamber and output...I need to buy a pair to compare with my LD25X.


how do they accomplish comparable excursion, I guess it's not an underhung design anymore?

you're a collector of speakers, aren't you... 

I've got a few too, I wonder how different the LD25X is from my Aura MR series, in sound. I blew one, and upon investigation the Aura is very strong in the magnetic gap, more than any of the small format/neo motor designs I have "inspected" over the years.

it had a pretty hardy aluminum former, maybe it didn't sing as good as the LD25X but it's supposed to be neo-radial in design too, so I would guess the two underhung topologies to maybe have a similar sonic characteristic.


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## 2010hummerguy (Oct 7, 2009)

I'm having a son in May so my office has converted to the nursery and most of my excess audio gear sold on Diyaudio and ebay (plus I had to raise funds to have Al/RAW here build me a custom center channel to match the beautiful arrays that CSS had him build 10 years ago. I then purchased from Bob at CSS last November). But I still have some goodies around which will never leave my family 

I'm betting the Aura sounds nothing like the LD25X...the LD25X sounds nothing like any dome I have ever heard. It has articulation and detail like my RAAL ribbons and literally no distortion. In my truck I can play them absolutely flat out on the highway with the windows down and the sound is pure and clear. And of course, sitting with the motor off they are even better  I used to have a pair in my DIY OB setup alongside SEAS Excel W15 and W22's and their detail mated extremely well with the very precise magnesium drivers. But I came across a deal on a pair of RAAL 140-15D dipoles from a Radio DJ/DIY audio fan in Germany and had them airmailed here. My new favorite tweeter but at an MSRP of $1900 per pair, the CSS is much more wallet friendly.

I am going to scrounge some gear out of my office today to post on ebay...then I'll probably order a pair of LD22 to test in my truck, the improved off-axis response of the curved waveguide may be helpful as my right tweeter is slightly off-axis


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## cajunner (Apr 13, 2007)

Architect7 said:


> I am going to scrounge some gear out of my office today to post on ebay...then I'll probably order a pair of LD22 to test in my truck, the improved off-axis response of the curved waveguide may be helpful as my right tweeter is slightly off-axis


oh, is the curved waveguide what is being called the curved faceplate?

I was thinking of a mild domed, large diameter faceplate but if it's a concave waveguide meant to improve dispersion pattern, (sound power, ?) that's another thing altogether..


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## 2010hummerguy (Oct 7, 2009)

cajunner said:


> oh, is the curved waveguide what is being called the curved faceplate?
> 
> I was thinking of a mild domed, large diameter faceplate but if it's a concave waveguide meant to improve dispersion pattern, (sound power, ?) that's another thing altogether..


The smooth curved faceplate acts as a small waveguide which improves off-axis response, here's the datasheet for both versions:

http://creativesound.ca/pdf/LD22.pdf


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## cajunner (Apr 13, 2007)

Architect7 said:


> The smooth curved faceplate acts as a small waveguide which improves off-axis response, here's the datasheet for both versions:
> 
> http://creativesound.ca/pdf/LD22.pdf


so, 86 db sensitivity is a little low...

but that waterfall, spectacular? 

looks good down to 3Khz @ 12 db/octave.

Not sure how that curved faceplate is doing it's thing.


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## mwmkravchenko (Oct 6, 2009)

This might get some of you guys interested:

Al and I have been working on some driver designs that are really interesting.

Stuff that actually performs as specified and has the tightest QC standards in the industry.

In fact each and every driver is tested before it leaves the factory. Yes it costs a bit more. But so does having QC problems and selling them off on Ebay. As far as it is up to me keep the quality high, keep it consistent and the rest will look after itself. I work with the factory that produces these! So think of them as my babies.


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## gfbl (Nov 26, 2008)

That's a good looking speaker


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## mwmkravchenko (Oct 6, 2009)

Thanks. It's also well made and soon to be available.


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## 2010hummerguy (Oct 7, 2009)

mwmkravchenko said:


> Thanks. It's also well made and soon to be available.


Good to know, is this based on the L22?


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## mwmkravchenko (Oct 6, 2009)

We will be doing a new faceplate, and offering the abilty to have custom 3D printed faceplates and waveguides.


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## mwmkravchenko (Oct 6, 2009)

> is this based on the L22?


No.

This is a redesign of the moving parts and a tight quality control of the fixed parts.

So this is an XBL tweeter.

It is 25mm

It has a low Fs.

And it has a large X-max for a tweeter.

But that's where any resemblance to anything similar stops.

This is new and improved on the original design. We paid careful attention to what went wrong, and have created a product done right.

No association with CSS for starters.


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## 2010hummerguy (Oct 7, 2009)

Very exciting to hear about this!


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## Electrodynamic (Nov 27, 2007)

I am very excited as well. Please shoot me an email at the htsales email address on my company web page (Stereo Integrity | Home). I would like to use a pair of these tweeters my VW Jetta that I'm having Mark build for me.


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## thehatedguy (May 4, 2007)

Nick, you sure you have the right Mark there?


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## mwmkravchenko (Oct 6, 2009)

> Nick, you sure you have the right Mark there?


Not sure.

My name is Mark.

I design loudspeaker drivers, and these are one of the latest tweeters I have done.

I have no problem shooting over a pair to Nick.

The ones in the picture are a pre production run. The body is 3D printed, and I have no face plates here at the moment. But that will change very shortly.

If there is demand for it, a proper car bezel mount could be done up. People in cars deserve good high end to!


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## 2010hummerguy (Oct 7, 2009)

Sign me up for a pair! I'll even take them in basic form


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## Electrodynamic (Nov 27, 2007)

thehatedguy said:


> Nick, you sure you have the right Mark there?


Probably not.


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## mwmkravchenko (Oct 6, 2009)

All Nick has to do is send an email.


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## mwmkravchenko (Oct 6, 2009)

@Architect7

Drop me a P.M.

Things can be arranged.


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## 2010hummerguy (Oct 7, 2009)

PM sent


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## bose301s (Dec 8, 2008)

I also would be up for a pair, I have the CSS LD25X currently and like them but have no clue how the QC on them was as I think I got them before the huge QC issues were discovered, and if I can get a set that performs as well or better with awesome QC and car specific mounts, well I'm all in.


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## 2010hummerguy (Oct 7, 2009)

Even off-QC LD25X sound good, just not to factory spec so you have to adjust crossover/eq/levels accordingly. Not in a bad way, just not predictable. Varying FS and impedance were the big issues. Hoping to install Mark's XBL tweeters once they arrive, review to follow


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## mwmkravchenko (Oct 6, 2009)

This will be going to a group buy as soon as I have the production schedule.


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## RAW (Aug 11, 2005)

OK notice the surround on the LD25X tweeter.Look at the way the surround is shaped it should be ROUND.










This is the LD25X faceplate removed look at the surround machined relieve on the face plate. This area is one of many of the issues with these LD25X tweeters.









Now look at the KAXBLTWT new XBL^2 tweeter from MARK notice the ROUND surround that this tweeter shows and the LD25X tweeter does not.









These issues i just mentioned above just touch what is wrong with the LD25X , the faceplates opening radius differs from tweeter to tweeter in every aspect.The radius shape ,radius opening over all size as well as the height the tweeter sits in the face plate.

Then the motor is another issue..

Bring on the new XBL^2 motor tweeter Mark did.


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## 2010hummerguy (Oct 7, 2009)

Wow never realized it was so far off...can't Wait! Should be arriving any day now, looking forward to dropping them in. My new Clarion amp is laid back on the top end so should match the xbl2 brightness without faceplate nicely.


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## Nismo (Jan 10, 2010)

I'm looking forward to this. Didn't realize it was so close!

Eric


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## 2010hummerguy (Oct 7, 2009)

Nismo said:


> I'm looking forward to this. Didn't realize it was so close!
> 
> Eric


Let me know if you ever plan to sell your Wr125S mids


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## Weightless (May 5, 2005)

How low will these play?


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## Nismo (Jan 10, 2010)

Architect7 said:


> Let me know if you ever plan to sell your Wr125S mids


If Mark makes the 3" XBL mids, I may. I will warn you though, that I've been working to get the bucking mag off, so one is a bit ugly ATM.

Eric


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## mwmkravchenko (Oct 6, 2009)

> How low will these play?


Fs is around 800 hertz

But how low is usually about an octave higher. 1600 hertz. Is safe.

If you have steep crossover slopes you can do 1000 hertz. Steep is 4rth order ( 24db/octave) 




> If Mark makes the 3" XBL mids, I may. I will warn you though, that I've been working to get the bucking mag off, so one is a bit ugly ATM.
> 
> Eric


If Mark makes a 3 inch the Wr125 will be left in the dust. It is a problem looking for a solution. Beautiful design done very badly at the factory. Wrong magnet has always crippled that woofer. The motor strength was much lower than the design called for. I have a neo version that will be a real piece of work sitting and waiting to be prototyped. The problem with such a small woofer is that not to many OEM's are that interested in such a little driver. 

If you want some VWR125s I have a decent stock of them. Drop me a line and you can have them if you make me an offer. They are new. Tested but otherwise not used.

I sure am not going to use them.


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## 2010hummerguy (Oct 7, 2009)

mwmkravchenko said:


> If you want some VWR125s I have a decent stock of them. Drop me a line and you can have them if you make me an offer. They are new. Tested but otherwise not used.
> 
> I sure am not going to use them.


Cool, always looking for backups for my HT setup. Email on its way


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## Nismo (Jan 10, 2010)

Mark, my WR125s are likely to end up as rear fill, so it's not a major issue to me. At this point, replacing the 3" Faitals means I'm already planning to swap something I haven't even installed yet!  The allure of well-designed XBL in EVERY speaker in my car is quite tempting!

Eric


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## bose301s (Dec 8, 2008)

I would also love a 3" mid, as long as it's done well and QC well. Every Klippel or other test I have seen has always shown a coil offset of decent amount, if that is eliminated they would all be amazing.


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## mwmkravchenko (Oct 6, 2009)

> I would also love a 3" mid, as long as it's done well and QC well. Every Klippel or other test I have seen has always shown a coil offset of decent amount, if that is eliminated they would all be amazing.


Klippel has been good in some ways and useless to misleading in others.

Wolfgang Klippel has successfully positioned himself, and his test system as being the best in the west.

That is not completely true.

And some of the methods used to generate some of the results are best efforts and practices. But in themselves are not the only way to quantify the results of what we test versus what difference it makes to us when we are listening.

To Wolfgang's credit he has spun popularity into a situation where there has been a greater drive to try and connect measurements to actual listening results.

But the Klippel system is not the only method to get identical results. And other systems actually create methods of measurement that are much closer to operating conditions than does the Klippel system. 

I just did some prototypes of different AMT's. The graphs looked good actually.

Listening to them was a whole other matter. They suck!

Some of what has become the Klippel measurements are not worth to much in real world terms.


The offset on the coil tells you more about the QC in the build house than anything else. All voice coils are supposed to be set to a predetermined height in the motor gap. But few build houses really do this right.

Have you worked with the designer and actually factored in the coil offset and seen the results, positive or negative in the distortion plots?

Voice Coil position is an example. Do you listen to a voice coil that is stationary in the first place?


Much of this stuff has become a brand orientation versus things that are really important.

Not knocking Klippel or the measurements in particular. But it how you use and understand the measurements that really matters the most.

And there are a boat load of measurements in a full Klippel report that are not that easy to understand.


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## bose301s (Dec 8, 2008)

I could also see the offset as an effect of most XBL driver designs. Most use a 2 piece top plate so all that has to be done is machine into the edge from one side as poppyseed to having to mill in the rebate in a solid top plate. While it shouldn't affect it much the fact that it isn't one piece of metal will increase reluctance in the magnetic circuit and I could see it making the magnetic field on the outward stroke slightly weaker than on the inward stroke. I would think this would show up as an offset in a Klippel even of there isn't one.


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## mwmkravchenko (Oct 6, 2009)

bose301s said:


> I could also see the offset as an effect of most XBL driver designs. Most use a 2 piece top plate so all that has to be done is machine into the edge from one side as poppyseed to having to mill in the rebate in a solid top plate. While it shouldn't affect it much the fact that it isn't one piece of metal will increase reluctance in the magnetic circuit and I could see it making the magnetic field on the outward stroke slightly weaker than on the inward stroke. I would think this would show up as an offset in a Klippel even of there isn't one.



Great observation.

You have an interesting grasp on the magnetic circuit properties. And a very correct use of the engineering vocabulary. 

But coil placement within the gap can also help to mitigate some of those problems.

A dual gap motor can only be built to it's best effect in a build house that really cares and understands what is being designed. That also means a build house that actually measures pertinent parameters, and that keeps their measurement equipment calibrated. 

On those fronts I could discuss insanities for quite a while.


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## bose301s (Dec 8, 2008)

mwmkravchenko said:


> Great observation.
> 
> You have an interesting grasp on the magnetic circuit properties. And a very correct use of the engineering vocabulary.
> 
> ...


I love this stuff, I am always trying to learn more about driver design, theory and technologies. I also helps that I am an electrical engineer so I had to learn at least some things relating to this. If there was someway I could get into the industry I would love it but I know how difficult it is in the current economy and I have student loans to pay and a stable job so I haven't risked it lol.


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## cajunner (Apr 13, 2007)

imho, if the Klippel measurements are difficult to assess, that doesn't disqualify the test.

I don't have any background in electrical theory and most of the pertinent points, are understood by me after reading a short primer that everyone can access online.

I also feel like Klippel has created an industry standard, but I don't know anyone else who is saying that there are other distortion analysis machines that create a more true picture of what is happening to the speaker under power, and with the assorted attachment/adapters, laser, etc. it's probably not surpassed except in perhaps, very narrowly defined parameters that on the whole, aren't as encompassing as the full monte of results off the KDA.

I've never run LEAP, looked at MLSSA or Dumax, or come within 100 miles of a speaker production facility but if I were serious about turning out sound quality based product, I'd spring for the Klippel reports from Red Rocks at a bare minimum.

That's just how it appears from the sidelines, since anyone actually sitting at a lathe and making models of motors after they play around with their FEA and FFT modeling software, is probably running on a different set of criteria for their purposes.

I used to like turning steel down, as a limited machinist running an 18" Cincinnati, with an 11' bed... and I would invest in a small reasonable quality lathe for the fun of it, as a hobby if I had the prerequisite theory already covered.

even better, would be to learn 3-D printing, and make injection molds for basket/motor interfacing, where you could compete with Alpine's research and development's casting budget, using low cost entry composites.

If it could be posed exactly how the Klippel is incapable of correlation, that would be helpful because the logical side of me wants to believe that there is very little one can do to produce a driver with a particular sonic signature that isn't discovered by the Klippel's graphic models, and that is the proof that Klippel is a revealer, I don't know how it could be construed as incorrect, unless there is proof that selective distortion is sonically superior from hearing tests.

If that is what you are saying, if the clearest, most true representation isn't actually our most euphoria-inducing, or emotion-provoking, or whatever, then you're on to something that I haven't seen being pushed in the literature.


everything I've seen is promoted to taking the wiggles out, not putting them in.


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## cajunner (Apr 13, 2007)

bose301s said:


> I could also see the offset as an effect of most XBL driver designs. Most use a 2 piece top plate so all that has to be done is machine into the edge from one side as poppyseed to having to mill in the rebate in a solid top plate. While it shouldn't affect it much the fact that it isn't one piece of metal will increase reluctance in the magnetic circuit and I could see it making the magnetic field on the outward stroke slightly weaker than on the inward stroke. I would think this would show up as an offset in a Klippel even of there isn't one.


how would the offset in the Klippel not be an offset, since the magnetic field being offset is exactly what the Klippel is best at figuring out?

I don't know what you mean by that, unless you expect that an air gap between the top plates is not calculable and/or not already a known quantity?

not to be contrary but I think the example you give is indicating a proper use of the KDA and not a variable hidden from the machine.

I know I maybe take too serious an interest in these little online babble sessions when it's just a pastime, an interest that coincides with my main hobby of audio but like you I've been interested for a long time and have my own ideas about magnetic circuit design, I enjoyed reading issues of Voice Coil, with the patent publishing of motors, and have a fair understanding of various design principles.

Like JBL's newish compression driver using dual ring radiator drive elements, that was something anyone could have churned out in their workshop, it's little things like that I like.

I'm looking forward to an explanation of what the design parameters of this latest motor encased in plastic- tweeter, using XBL is doing. Are those (appears?) felt pads on the side acting as miniature aperiodic damping, or just floating the assembly in loose casing? 

Is the use of a plastic prototype shell/frame able to test at more than a low power dissipation, or will the production models have more steel involved?

that's the kind of engineering banter I want to read/participate in, am I right?


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## mwmkravchenko (Oct 6, 2009)

Klippel has positioned itself like Apple or Bose.

People hear those company names and they think good stuff.

That is my principle problem.

Being forced into some one else's view of quality. Brand recognition over proof of utility.

cajunner you have proved the validity of requiring a Klippel report. You trust that the report is telling you the truth. 

The crazy thing is I use a modest system to to test and measurement. I use the Smith&Larson WooferTester Pro.

And I can do almost all of the same tests. And some of the tests linearity for example are more true to life than the Klippel testing.

The reason is simple. Klipppel uses DC pulses to excite or move the driver over some of it's tests. My humble little box ( mine as in the one I use ) uses AC for the same tests. The difference is interesting when you consider that functioning loudspeakers are run on AC. And there is a lot of mathematical correction required for transfering DC signals to the AC signal domain.

As for a real life example of what can for wrong in Klippel reports the X-max is usually my biggest pet peave.

You can sometimes see in the graphs points in X-max that are not possible in actual operation. The report says it is so. But I have learned over the years to do this neat little test.

I can operate and run the machine tools to make a driver to. I'm not a machinist, but nor do I consider myself a mechanic and I have done 7 short block rebuilds. It just takes me forever. I don't do it often so every time I have to dust off the cobwebs. 

I take every driver, clamp it in a vice in my cabinet shop. Take a riser block to get a center cone height and balance a little stick horizontally on the block. The block is usually about 4 inches long. I take the cone from the rear side and push it as far as is possible to get maximum mechanical excursion. The little stick gets moved from the rest point. I record this. Warm or cold this does not change very much. New or broken in, this does not change very much. And yes I have heard of a dial indicator and have a few. Just easier to mark the start and stop points of a little stick!

From there I can do some neat testing. I can physically measure the coil height and gap height. I can model the motor strength versus excursion. I have worked on enough drivers that I can have pretty good confidence in the modeling software. I use FEMM for the magnetics work. It is a 2D magnetics and thermal modeling simulator. It's been proven to be very accurate. Within a few percent of a silly expensive software suite called ANSYS. And I can also measure the motor strength versus excursion to within 1.5mm accuracy with the WooferTester Pro. ( It does this by using two microphones, and doing a time of flight calculation in the time (phase) domain.) If I have a hunch that I need better resolution I have a Baumer Laser range finder ( Not quite the same one as Klippel. Mine has a little lower resolution ) that gets me a repeatable 0.3mm accuracy.

So I have and use a poor man's Klippel. 

I have zero problem getting independent tests. And an hour from me is a great test facility that has a full Klippel system. Warkwyn Acoustics. They are great people.

My only point is that there are always other ways to do something.

And do not drink so much of other peoples KoolAid that you forget to use your head to consider the veracity of their statements.

Be they good or bad.

I have left companies because of falsified testing info. It rubs me the wrong way. And basing your companies future on lies about your products has nowhere to go but down. I do not consider people who are interested in quality loudspeakers to be foolish. I provide a quality product with quality design and manufacture. And they also sound pretty good :surprised:


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## mwmkravchenko (Oct 6, 2009)

Masters bose301s and cajunner

Coil position is interesting until you think about how a speaker works. If the position as tested in Klippel or any other software package is relatively close then you are not going to hear it in use. I'll throw a percentage in here to qualify "close".

You could say within 1mm.

How about a tweeter?

Not good enough right?

50% Most tweeters have a X-max less than 2mm.

Still not good enough.

So what will be a standard to look for?

In the Klippel report or others there should be a graph plotting distortion versus excursion. That is where it really matters.

Now keep in mind some interesting little facts. Most of the time for a huge amount of the tines we listen the drivers are running at under 3 to 4 mm of excursion. Tweeters are even less. So take the point of rest and look from that range to 4 to 6 mm mark and you will see what most drivers are doing up to and about 90 to 94 db. That is the point where it is pretty loud. As in you can't really talk over it without some serious yelling.

Large excursions are another thing to consider, and that will be covered when I start the thread on the woofers.


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## mwmkravchenko (Oct 6, 2009)

Well a couple gents should have the new tweeters by now. I know Nick has had them for quite a while. And the other set were waylaid by USPS and Nick came to the rescue.

Thanks Nick!

I have limited options from Canada!


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## req (Aug 4, 2007)

i didnt see this thread until now, and i have a pair of the 'ebay sold' LDX25's that were pair-matched from a while back and most likely in one of the pictures from the first page with the green stickers on them.

looking at the image above with the deformed surround on the tweeter due to the faceplate - am i looking at this issue as well?

i would be very interested in these new tweeter versions before i finilaize my sail panels with the LD25X.


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## RAW (Aug 11, 2005)

All the LD25X tweeters I measured and then I marked the FS on the backs of the tweeters along with the impedance.
DO NOT look at the new XBL tweeter from Mark as a drop in into the CSS faceplate.They do not work. The CSS faceplate has to many issues


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## mwmkravchenko (Oct 6, 2009)

> All the LD25X tweeters I measured and then I marked the FS on the backs of the tweeters along with the impedance.
> DO NOT look at the new XBL tweeter from Mark as a drop in into the CSS faceplate.They do not work. The CSS faceplate has to many issues



Thanks Al!

Exactly.

A completely new face plate is in the works. 

This is a redesign, not a copy of a failed design.


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## edouble101 (Dec 9, 2010)

Any idea when the group buy will be posted?


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## req (Aug 4, 2007)

i was looking for a complete replacement from my LD25X with this new driver you are discussing here.


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## mmiller (Mar 7, 2008)

I might be interested in a pair of these, I'm fairly local to Mark...


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## cajunner (Apr 13, 2007)

it is my thought process that there will be several higher end, perfectionist types who will want to replace their LD25X with the new models due to a subjective, (perhaps objective, since we all run our tweeters inside of their BL flat zone, haha) bias that prevents people from installing the older tweeters with surround issues, faceplate mating issues, impedance variability issues, frequency response issues...


all these issues, wouldn't it make sense to just put your old, tired, proven inferior LD25X tweeters in a pile for the less choosy of the DIYMA crowd?

you know, a "take a tweeter, leave a tweeter" kind of thing, so those old decrepit mismatched, hodge-podge of an engineering mess, tweeters, aren't wasted?

I'll go first, I have a pair of Hollywood Sound from their early days, came from a highest end set, with the cast frame midranges.


I'll be willing to put those in, and take away a set of LD25X as a favor to the community.


anyone can come in and leave a pair of their LD25X, and take my known good Hollywoods, just to keep it going...


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## mwmkravchenko (Oct 6, 2009)

Ok the short story is I can get the tweeter driver made in fairly short order.

The next question is simple.

I planned on selling the drivers for $100 a pair shipped.

My problem is that the faceplates are hitting me harder than I was hoping.

Now I'm looking at $115 a pair shipped.

The faceplates cost me $30 a set. They are custom made in Canada. It will allow the wonderful made in Canada designation. I'll assemble them as need be.

For car audio I'm making the faceplate as small as is practical. The dome will be covered by black painted expanded metal. And I have designed in some ridges on the O.D> of the faceplate to facilitate a simple 2 inch hole for flush mounting.

Time from beginning of group buy to having product is about 60 days. I have some control over that by shipping via my air freight account instead of ocean carrier. Costs more but gets here in 5 days. Here is close to Ottawa Canada.

So setting up the group buy is as simple as getting a moderator on side and pointing me in the right direction.


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## req (Aug 4, 2007)

k im in


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## mwmkravchenko (Oct 6, 2009)

> it is my thought process that there will be several higher end, perfectionist types who will want to replace their LD25X with the new models due to a subjective, (perhaps objective, since we all run our tweeters inside of their BL flat zone, haha) bias that prevents people from installing the older tweeters with surround issues, faceplate mating issues, impedance variability issues, frequency response issues...


That is the difference.

Consistency. There were some good tweeters in the LD25X batch. The first two top trays in the shipment. Standard manufacturers tricks. Put the good ones on top.

I work with a factory where every part of the build is checked. Every motor is tested for a go/nogo on motor strength. Every dome/coil assembly is weighed. The glue is metered. The glue metering is tested every 20 minutes. The entire driver run is checked for Fs within a 3 db window on a ClioQC system. These guys are as crazy as me in terms as quality control.









Here you get to see the measurement system, and the upper and lower limits of acceptability. The response in the test enclosure is not flat. What you look for is repeatability. We keep the margin of error with a plus or minus 1.5db window. The central line is the actual device under test. And we calibrate the measurement every so often with the measured and verified prototypes.









Here are the actual settings within Clio QC









Yes those two ladies actually test every single motor at 4 points for flux density.









Genuine Ferro Fluid. Not the knock off stuff. It's $1400 U.S. per liter. But you get what you pay for.









True automatic, metered dispensing system.









Regular glue dispensing is measured for QC, mass, consistency, setting times.









Yep the giant chrome dome is me. I work there from time to time spitting out interesting driver designs.

























Ever Fell like your being watched???


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## req (Aug 4, 2007)

sooooo....

i dont want to finish my tweeter install if i can get this as an upgrade lol


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## teldzc1 (Oct 9, 2009)

Any idea on timing for the group buy? I'd be interested. Pics of the faceplate would be helpful.

Sent from my SAMSUNG-SM-N900A using Tapatalk


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## mwmkravchenko (Oct 6, 2009)

This is basically what I'm shooting for in terms of a faceplate.









So to be clear. No branding, fixed mount as in no eyeball movement. Black painted expanded metal grill. A nice trim ring around the edge to allow a drop in installation in a 2 inch hole.

Negotiating to get this faceplate done for $15 a piece. Might go up a couple bucks depending on the grill. Fun and games.

As for group buy soon. Very soon.


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## Guest (Jun 21, 2014)

That would be nice !


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## teldzc1 (Oct 9, 2009)

That would be sweet! You mentioned in an earlier post something about a waveguide required to flatten the response. Will this compact faceplate fill the need? It does look really nice.

Sent from my SAMSUNG-SM-N900A using Tapatalk


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## mwmkravchenko (Oct 6, 2009)

http://www.diymobileaudio.com/forum...ion/164686-kaxbltwt-groupbuy.html#post2119503


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## CDT FAN (Jul 25, 2012)

I know this is an older thread, but I figured it would be a good place to get the best notice.

I have a pair of these LD25x tweeters and I would like to get another one as a spare in case one blows out. Does anyone have one they would like to sell?


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## 2010hummerguy (Oct 7, 2009)

Good luck, the only pairs I've seen for sale during the last 12 months were out of Poland and he would not ship overseas (nor did he understand English). I had five extra pairs that I sold last year to a buyer in Singapore and still kicking myself over it. I reached out to him to see if he'd sell any back to me and he has no intention of ever getting rid of them (wise man). Doh!!!


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## mwmkravchenko (Oct 6, 2009)

You guys know I have a much improved version of this tweeter available. 

It's better than the original. And all are matched plus or minus 1.5 db.


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## CDT FAN (Jul 25, 2012)

mwmkravchenko said:


> You guys know I have a much improved version of this tweeter available.
> 
> It's better than the original. And all are matched plus or minus 1.5 db.


How did they improve on it? I know I saw about a replacement somewhere, but I don't remember the model number. Can you tell me more about it?

EDIT. Nevermind. All I had to do was scroll up. 

Can you describe the difference in the sound of the two models?


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## mwmkravchenko (Oct 6, 2009)

Yes.

The sound is clean, clear and above all else the drivers are absolutely consistent. 

I improved the dome choice, and actually use ferro fluid in every driver.

A fatal failing in the other version. 

Most had little to no ferro fluid. 

Plus every single driver I provide is 100% QC checked. 

They meet a golden standard, or they are rejected from the driver run.


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## CDT FAN (Jul 25, 2012)

So, where do I get some of them and how much do they run?


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## mwmkravchenko (Oct 6, 2009)

Keep your eye on my website. 

I'm working on a faceplate currently. 

All information will be posted there.


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## cajunner (Apr 13, 2007)

CDT FAN said:


> How did they improve on it? I know I saw about a replacement somewhere, but I don't remember the model number. Can you tell me more about it?
> 
> EDIT. Nevermind. All I had to do was scroll up.
> 
> Can you describe the difference in the sound of the two models?


how nice is it that you can ask the designer of the tweeters himself, who laboriously slaved over the build process from the very beginning to the end.

go to his website and click on his picture slideshows.

watch a few of the videos.

then get in on his new batch of tweeters, to be available in a month or so, give or take.

they won't be quite as cheap as the LD25X but the performance of the tweeters so far, seems to echo what has been stated over and over about build quality and consistency between drivers.


the little blemish of whited super glue having to be cleaned from a few of the first batch that went out, and anecdotal evidence of at least one tweeter where the assembly was couched and the terminal opening wasn't perfectly aligned to allow the insertion of insulated terminals, is minor compared to those CSS LD25X versions, imho...

it looks like the second batch may include some parts not off-shore sourced, but also with the possible inclusion of different anodized colors or other aesthetic changes. But I wouldn't worry about the product, it appears Kravchenko Audio has this under control and making headway against the bigger fish of the high-end audio seas.


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## CDT FAN (Jul 25, 2012)

cajunner said:


> how nice is it that you can ask the designer of the tweeters himself, who laboriously slaved over the build process from the very beginning to the end.
> 
> go to his website and click on his picture slideshows.
> 
> ...


Yes, it is cool to get the news straight from the person or people who was responsible for the existence of the product. No one knows or appreciates the product like they do. I have been to the website, but didn't find any prices until just a few minutes ago.


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