# Horn System 96 Civic



## Rybaudio

Hello everyone,

Long time audio guy here - haven't done a car system in several years but I'm driving more these days and getting ready to put something into my car. I've wanted to do a horn system for a while so a few years ago I asked around for good horn cars and eventually sought out and found a 96 Civic.

Here's what I've got so far for the details:

- 96 Civic (sedan, auto)

- HLCD, most likely ES mini horns (open to suggestions) from 1k+
- midbass in the doors (6"-10") 1k down to 100ish
- sub(s) out back (whatever's needed to keep up - figure out later)

- miniDSP for processing (open to suggestions)
- whatever power is needed
- some digital media source


Here are some things I'm wondering about:

*Horns:* ID/ES minis seem to be a good default option from what I've read. Are the full size worth considering for this vehicle? Are there any installation concerns specific to this vehicle? Just eye-balling it, it looks like I can fit them under there without any real problems.

*Midbass:* I pulled the door panel off today and it looks like I can fit a good 6" behind the factory grill, probably beefing up the mounts. I might be able to fit an 8" behind and with a little cutting have enough space for the cone to fire through the stock grill. Anyone reading ever tried that in this vehicle? If that doesn't work, it should be easy enough to fab up a new bottom of the door panel to hold an 8" or 10."

I took a quick look around today and found the Faital Pro FE200 drivers. They seem to be the compromise I'm looking for (high sensitivity in midrange, usable as a midbass, 4 ohm, and inexpensive). Does anyone have any experience with them? The measurements on Faital's site are plotted on a 100 dB scale (lol) so it's a little tough to see what's going on in but there don't appear to be any major problems <1kHz. Also, are there any other drivers worth considering?

*Processing:* I've had my eye on the MiniDSP products for a while. Is there anything comparable to the 2x8 kit ($300) worth considering? Do any higher end head units have real processing capability in them? I just need 5 channels out with a few bands of EQ on each, crossover, time alignment, and the ability to send mono to the sub.


Those are the main concerns. Amps and subs will just be what physically gets the job done, and I'll have to take a look around for a decent source. Thanks for any input you can give!


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## jpeezy

left side should go fine , you'll have to unbolt hood release and move it, and on the right side if you drop the glove box(3 8mm bolts along bottom if i remember correctly),hold the right side horn (fullsize) up you'll see where the body rubs up against the blower box, you'll need to sand a little of back of horn body, and you see a couple of ribs in blower box near where you would put interior air filter (if it actually had one) sand those down as well, then they should fit fine. you may also depending on the comp. driver have to notch out tops of kickpanels.I can not remember for certain but i may have also relocated the ecm that is normally in the pass. kick, to the footwell just in between the kick area and the center console,( if you do this make sure you reuse the bolts and a heavy ground strap or cable and ground the chassis of the ecm).good luck. By the way my fullsize horns worked extremely well in my 2000 civic si. make sure you include a very efficient midbass. I had 8's in the kick, and I had a 5 spd as well, it fits, lil tight but it fits.


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## Patrick Bateman

I'm kind of a broken record on this, but I think there's a solid argument to be made for midbass arrays. The Faital is $48 and has a 1.5" voice coil. An array of smaller drivers will generally yield higher power handling, higher displacement, and improved power response by spreading out resonances in the car. I am personally using an array of four 3" woofers per side. More displacement than an 8" prosound driver and higher power handling. A single 3" woofer won't move a lot of air but four of them will.


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## subwoofery

Patrick Bateman said:


> I'm kind of a broken record on this, but I think there's a solid argument to be made for midbass arrays. The Faital is $48 and has a 1.5" voice coil. An array of smaller drivers will generally yield higher power handling, higher displacement, and improved power response by spreading out resonances in the car. I am personally using an array of four 3" woofers per side. More displacement than an 8" prosound driver and higher power handling. A single 3" woofer won't move a lot of air but four of them will.


4 x 3" drivers will have the cone area of a 6" driver if I'm not mistaken (and if my math isn't off). 

Kelvin


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## Patrick Bateman

subwoofery said:


> 4 x 3" drivers will have the cone area of a 6" driver if I'm not mistaken (and if my math isn't off).
> 
> Kelvin


The ND91 is Klippel tested, and shows 30% more xmax than your average prosound 8": http://www.parts-express.com/pedocs/specs/290-226-dayton-audio-nd91-8-specifications-8382.pdf

It also has a cone that's closer in surface area to a 4" woofer, because the frame is utterly flimsy.

Basically it's a 3" woofer that moves about as much air as most 5" woofers.


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## Rybaudio

4 x ND91 is still about 7 dB less sensitive than a single 8FE200 and costs twice as much. To match cone area (30 vs. 190 cm^2) you'd need more like 6. Using 8 x ND91 brings you up to within 3-4 dB of the 8 sensitivity wise in the mid band, but cost is 4x and now things get complex when you're talking about placement because the array will be directive up where I want to mate with the horn.


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## Rybaudio

jpeezy said:


> left side should go fine , you'll have to unbolt hood release and move it, and on the right side if you drop the glove box(3 8mm bolts along bottom if i remember correctly),hold the right side horn (fullsize) up you'll see where the body rubs up against the blower box, you'll need to sand a little of back of horn body, and you see a couple of ribs in blower box near where you would put interior air filter (if it actually had one) sand those down as well, then they should fit fine. you may also depending on the comp. driver have to notch out tops of kickpanels.I can not remember for certain but i may have also relocated the ecm that is normally in the pass. kick, to the footwell just in between the kick area and the center console,( if you do this make sure you reuse the bolts and a heavy ground strap or cable and ground the chassis of the ecm).good luck. By the way my fullsize horns worked extremely well in my 2000 civic si. make sure you include a very efficient midbass. I had 8's in the kick, and I had a 5 spd as well, it fits, lil tight but it fits.


Thanks a ton for the concrete advice! I have a couple questions but I gotta hit the road right now so they'll have to wait.


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## Patrick Bateman

Rybaudio said:


> 4 x ND91 is still about 7 dB less sensitive than a single 8FE200 and costs twice as much.


For the most part, I don't care about sensitivity, I care about output and smoothness. While the sensitivity of four ND91s is lower the output is about the same.



Rybaudio said:


> To match cone area (30 vs. 190 cm^2) you'd need more like 6. Using 8 x ND91 brings you up to within 3-4 dB of the 8 sensitivity wise in the mid band, but cost is 4x and now things get complex when you're talking about placement because the array will be directive up where I want to mate with the horn.


Complexity is definitely higher. Cost will probably be higher.

Basically I see a lot of people saying "Hey I want to buy this big expensive prosound 8" woofer and put it in my door." And I'm saying "hey you can get the same output from an array of smaller drivers. And the smoothness may be better. "

Even JBL and Meyer are going this route; they're using drivers as small as 2" in some of their prosound products, and using a LOT of them.

TLDR: Don't underestimate the output of an array of small drivers. The performance might surprise you. It's particularly handy in a car environment, where four door vehicles already *have* four stock holes for 5"-7" drivers.


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## Eric Stevens

Patrick Bateman said:


> The ND91 is Klippel tested, and shows 30% more xmax than your average prosound 8": http://www.parts-express.com/pedocs/specs/290-226-dayton-audio-nd91-8-specifications-8382.pdf
> 
> It also has a cone that's closer in surface area to a 4" woofer, because the frame is utterly flimsy.
> 
> Basically it's a 3" woofer that moves about as much air as most 5" woofers.


Yes but it is still only 81dB 1 watt/ 1 meter and 4 will never come close to the output of a driver with sensitivity of 94 dB 1 watt/ 1 meter. This holds true if you want to believe that you achieve a 3dB increase in sens when you double the drivers. Adding 6dB which would never be achieved in the real world is still - 7dB. 

Add to that the tonality differences between the styles of drivers and you have a recipe for yuuuuuukkkkkk.


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## Patrick Bateman

Eric Stevens said:


> Yes but it is still only 81dB 1 watt/ 1 meter and 4 will never come close to the output of a driver with sensitivity of 94 dB 1 watt/ 1 meter.


As long as you have sufficient power, the sensitivity of a driver is irrelevant. Displacement is what determines output, not sensitivity.

If you have two drivers, one that's 6" with an xmax of 8mm and an efficiency of 85dB, and another that's 6" with an xmax of 2.5mm and an efficiency of 91dB, the first driver will generate more output because it has higher displacement.




Eric Stevens said:


> This holds true if you want to believe that you achieve a 3dB increase in sens when you double the drivers. Adding 6dB which would never be achieved in the real world is still - 7dB.


Getting two midbasses to sum constructively is trivially easy. 200hz is almost TWO METERS long. If you can get two midbasses within half a meter, they're going to sum.



Eric Stevens said:


> Add to that the tonality differences between the styles of drivers and you have a recipe for yuuuuuukkkkkk.


And you've heard how many cars with distributed midbass arrays?

I'll concede that line arrays of midbasses sound like ****, I found that out the hard way when I tried that about a decade ago. But distributing the midbasses has the same effect in a car as distributing subs in a house does. (http://www.enjoythemusic.com/diy/0812/distributed_bass.htm)

'Tonality' is determined by frequency response and power response. One of the things that always sound 'wonky' about under dash horns is that they have massive pattern flip. Basically the asymmetrical shape of the horn means that the horn means that the horn isn't a good match for symmetrical drivers... You know, like an 8" midbass. *Pattern flip is the reason that underdash horns often sound 'thin'.* One big difference that I hear with distributed midbasses is that the sound is more 'diffuse', which masks the wonky power response of an underdash horn.



To make this perfectly clear, I'm not saying distributed midbasses are superior. They're just another option, one of many. I think that a lot of people don't realize how long midbass frequencies are, so the idea of having two midbasses seperated by half a meter might sound nutty. But it works fine; and we have two convenient locations if we have a four door car.

P.S. Come out to T.H.E. Show tomorrow! Would love to talk shop sometime.


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## thehatedguy

It won't have more displacement when you factor in the XO. You will burn the coils of the 3s long before you start to match output of the higher efficiency speaker.


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## fenis

Not to mention power compression - you want to fit as big a midbass with the highest sensitivity possible to match the ridiculous sensitivity of the horns.


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## mikey7182

I know Patrick started off talking about multiple 2-3" drivers, but given the four 6-7" door locations most vehicles have (like he mentioned several times), why not a distribution of two pair of 6-7" PA mids? I went straight from a pair of 2118H in the doors to the ported pair of 2204H behind me, and in a single cab never had the option of trying midbass in multiple locations through the car, but I will probably be picking up a sedan in a few months and will likely do a midbass distribution in the doors. If I could fit two pair of 8" drivers, that would be awesome, but it will depend on the car. Either way, if you did two pair of at least 6" mids in the 4 doors, some midranges in the kicks, and horns, I think that would be a fun project to try, keeps everything looking factory and you don't have to build obtrusive door pods. Run the midbass in parallel per side and HPF them at 200-250. Again, 8" drivers would be ideal due to the lower Fs, but if you got something like four B&C 6NDL38 going, they'd do just fine down to 100hz. There are obviously less expensive options; that's just a pair of 6" PA mids I've owned.


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## Eric Stevens

Patrick Bateman said:


> As long as you have sufficient power, the sensitivity of a driver is irrelevant. Displacement is what determines output, not sensitivity.
> 
> If you have two drivers, one that's 6" with an xmax of 8mm and an efficiency of 85dB, and another that's 6" with an xmax of 2.5mm and an efficiency of 91dB, the first driver will generate more output because it has higher displacement.


Sensitivity is not "irrelevant" at any frequency, as the frequency gets lower it is a less significant factor in the maximum output potential.

You are only looking at one aspect of a complex equation. The output at low frequency is effected by displacement when you are looking at maximum mechanical power handling and calculating maximum potential output levels. Please take the time to model a 6.5" driver with a high pass of 12dB octave at 80Hz which is very typical and look at excursion vs frequency and I think you might just see how far off the mark your statement is.

So your statement is somewhat correct if using the 6.5" drivers as subwoofers.


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## Eric Stevens

Power response is necessary to understand when using or setting up a system but more important than that is impulse response and direct versus reflected energy and that is where my under dash horns excel. 

In pro audio they are using multiple drivers in an array soi the can do pattern control using dsp not because they can get more output that way.


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## Eric Stevens

oh and if you really want some high output without needing high excursion just use a port on your mid bass driver. then you can have your cake and eat it too with a little sacrifice in the group delay department.


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## mikey7182

Eric Stevens said:


> oh and if you really want some high output without needing high excursion just use a port on your mid bass driver. then you can have your cake and eat it too with a little sacrifice in the group delay department.


My midbass are currently ported but unrealistic for most installs. What are your thoughts on my idea above (which isn't really MY idea)? If a large format, ported midbass at one end of the spectrum, and an array of small drivers plugged under the dash, etc is at the other end, then assuming use of a dedicated midrange, does dropping four 6-7" midbass in factory doors sound like a reasonable and feasible compromise? Are there reasons that wouldn't work, or are there simpler ways to achieve the same output while avoiding fabrication/modification?


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## Patrick Bateman

Eric Stevens said:


> oh and if you really want some high output without needing high excursion just use a port on your mid bass driver. then you can have your cake and eat it too with a little sacrifice in the group delay department.


I think that's a good idea too. In my case it's a bandpass.

Again, I need to stress that I don't think that distributed midbasses are the *only* solution, but they're a *viable* solution.

I find that distributing the midbasses makes the soundstage more 'diffuse' and the sound is "smoother."










I look at the octaves like a pyramid.

At the top of the pyramid are our high frequencies, from 2khz to 20khz. 2khz is 17cm long. Due to that length, I'd like to keep the midranges withing about 6cm of the highs. That basically means I can use multiple mids, *but I need to keep them very very close.* About 2.5". It also means that I need to use one and only one tweeter. If I violated that rule, all of the high frequencies cues needed for good imaging fly out the window.
The pyramid goes treble-midrange-midbass-subs. The midbass is tricky, becasuse you need a lot of power and displacement for good dynamics. But we have a lot of flexibility with midbass placement. *The wavelengths are so long, if we can keep the midbasses within about a half meter, they're going to merge into a single source.*
Low frequencies are possibly the easiest of all. Just buy whatever moves a lot of air and be done with it.


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## Eric Stevens

a distributed array might smooth frequency response on an rta or even fft measurement but it completely ignores time and phase between other drivers and L/R channels which are all part of creating a realistic sound stage with focused images, including space and depth between images.

The distributed array might improve one area but will cause far more problems than it cures. if you run it up too high you are going to have NASTY comb filtering to boot probably as low as 500 Hz.

The idea of a distributed array just goes against everything i have learned and experienced in car audio.


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## Patrick Bateman

Eric Stevens said:


> a distributed array might smooth frequency response on an rta or even fft measurement but it completely ignores time and phase between other drivers and L/R channels which are all part of creating a realistic sound stage with focused images, including space and depth between images.
> 
> The distributed array might improve one area but will cause far more problems than it cures. if you run it up too high you are going to have NASTY comb filtering to boot probably as low as 500 Hz.
> 
> The idea of a distributed array just goes against everything i have learned and experienced in car audio.


Here's a subjective description of the difference I hear:

With a single midbass, the sound appears to emanate from the loudspeaker. This can be good, or this can be bad. If you can figure out a way to get the midbass all the way back into the firewall, you'll have good depth, but you may not have width.

With the midbass array, the low frequencies seem to envelope you. They are diffuse, they are smooth. It is anything but pinpoint.

Whether this signature is someone's cup of tea is really going to be a personal choice.

I once ran line arrays at home, and I quickly grew tired of how it made *everything* huge. For instance, if someone in a movie was talking, the line array would make it sound like they were eight feet tall and twenty feet wide. It's a neat trick, but it's not hifi. (Unless they're actually twenty feet wide, lol)

But with bass? Yeah, I like it with bass. I like that sensation that the bass is all around you. Not coming from the front, not coming from the back, it's surrounding you. The soundstage is still up front, because it's anchored to the midrange and the tweeters. But the bass envelopes you.

TLDR: You're right, the phase response will be all over the map in the bandwidth of the midbass array. Do I mind? No, not really, but YMMV


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## Rybaudio

There are a couple separate issues here.

First, let's compare the performance of multiple small drivers (tightly packed) with a single larger driver. In an application there is typically a limitation on the size of the driver/array based either on physical constraints (fit it in the door) or directivity on the high end of the frequency range it's used over. For a given diameter, a single circle maximizes area, so generally a single driver is going to have the edge cone area wise. It's also generally easier to design larger drivers for more excursion, so the single driver generally will edge out the array in maximum displacement. In order to get away from that trend, compromises need to be made somewhere along the line.

In the case of the ND91 array you suggested earlier, the ND91s have been designed to trade off efficiency for low end extension and displacement. Four of them tightly spaced takes up about the same area as the 8FE200, and does have about the same displacement, but the efficiency is lower by a factor of ~4. If you designed them to be more efficient, something else would have to give.

That particular arrangement costs twice as much in drivers and would require 4x the power to achieve a given level. At a given level each coil would be getting the same power as the coil in the 8FE200. The amps needed would cost a lot more and power compression and thermal failure would set in significantly earlier, limiting the effective usable output. The drivers are also fairly close in mounting depth to the proposed 8. It just doesn't make sense from any angle. I am not dismissing the array idea outright - I just doubt you'll be able to find an arrangement that makes sense from all the angles.


Second, you seem to be talking about distributing the midbasses around the car to smooth things out spatially, like you might do with subs in home. In a car the sparse modal region is shifted up (relative to a living sized room) into the midbass so there might be some validity to that. One issue that I've thought about is the lowest mode left to right. This should be around 100 Hz (set half wavelength to width of car to approximate). The phases of the sides are opposing - single node in the middle. The problem I see is that a single driver on either the left or right in the door or kick would excite the mode, but if you turn both on, they drive the mode opposite in phase so they cancel. The result is that you get drastically different responses playing a single channel and playing a mono signal. Maybe playing with distributing the midbasses could help with that.

In any case, in my system I want a single driver or drivers to cover 80-1k, and I can't have sources all over the place shooting out 1k, so it's not really feasible... will have to keep the idea in mind though.


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## Patrick Bateman

Rybaudio said:


> There are a couple separate issues here.
> 
> First, let's compare the performance of multiple small drivers (tightly packed) with a single larger driver. In an application there is typically a limitation on the size of the driver/array based either on physical constraints (fit it in the door) or directivity on the high end of the frequency range it's used over. For a given diameter, a single circle maximizes area, so generally a single driver is going to have the edge cone area wise. It's also generally easier to design larger drivers for more excursion, so the single driver generally will edge out the array in maximum displacement. In order to get away from that trend, compromises need to be made somewhere along the line.
> 
> In the case of the ND91 array you suggested earlier, the ND91s have been designed to trade off efficiency for low end extension and displacement. Four of them tightly spaced takes up about the same area as the 8FE200, and does have about the same displacement, but the efficiency is lower by a factor of ~4. If you designed them to be more efficient, something else would have to give.
> 
> That particular arrangement costs twice as much in drivers and would require 4x the power to achieve a given level. At a given level each coil would be getting the same power as the coil in the 8FE200. The amps needed would cost a lot more and power compression and thermal failure would set in significantly earlier, limiting the effective usable output. The drivers are also fairly close in mounting depth to the proposed 8. It just doesn't make sense from any angle. I am not dismissing the array idea outright - I just doubt you'll be able to find an arrangement that makes sense from all the angles.
> 
> 
> Second, you seem to be talking about distributing the midbasses around the car to smooth things out spatially, like you might do with subs in home. In a car the sparse modal region is shifted up (relative to a living sized room) into the midbass so there might be some validity to that. One issue that I've thought about is the lowest mode left to right. This should be around 100 Hz (set half wavelength to width of car to approximate). The phases of the sides are opposing - single node in the middle. The problem I see is that a single driver on either the left or right in the door or kick would excite the mode, but if you turn both on, they drive the mode opposite in phase so they cancel. The result is that you get drastically different responses playing a single channel and playing a mono signal. Maybe playing with distributing the midbasses could help with that.
> 
> In any case, in my system I want a single driver or drivers to cover 80-1k, and I can't have sources all over the place shooting out 1k, so it's not really feasible... will have to keep the idea in mind though.


The really critical thing to understand about this - is that output is determined by displacement.

For instance, you note that the efficiency of the ND91 array is lower, and that is true.

But it doesn't matter, *because output is determined by displacement*









The CSS VWR126X is a good example of this phenomenon. Here's bikinpunk's klippel test of the driver. It's cone is about 4" in diameter and it has an efficiency of 84dB. (very low!)


































Yet the driver can get plenty loud.
In the measurements above, we can see that the CSS VWR126X ($50) has lower 3rd harmonic distortion from 500hz to 1khz than the B&C 8NDL51 ($160.)

And I'm not pitting the CSS against a cheap driver - *the B&C midbasses have distortion levels which are often lower than the boutique drivers from ScanSpeak and Seas.*

B&C is some serious gear, and the lowly CSS can beat it, even at 100dB!



Now, at this point, you'd say "who cares, 100dB isn't much."


That's where two more "tricks" come into play. First, we run one drive inverted and out-of-phase - that nukes second harmonic distortion.

The second trick is to pile on as many midbasses as will fit. In my case, I am using four per side.




It's definitely tricky, but I think it's rewarding. I wouldn't do this array with a bunch of cheap drivers, because then you'll just end up with an array that is loud and grungey. I also wouldn't do this trick with a bunch of ScanSpeak drivers, I have better places to spend my money. But when you find that ONE driver that combines Low Cost, Low Distortion, and High Displacement, you got yourself a winner!


At this point the weak links in my system are actually my subwoofer and my midranges. My midbasses and my tweeters can handle all the power I can throw at them. (I actually blew up a midrange right before the MECA show.)


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## Jesus Christ

Patrick Bateman said:


> For instance, you note that the efficiency of the ND91 array is lower, and that is true.
> 
> But it doesn't matter, *because output is determined by displacement*


So how much power does it take to get one of your nd91's to hit xmax at 250hz? 500hz? Hint, you'll have melted the coil long before you get there.


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## Rybaudio

Patrick Bateman said:


> But it doesn't matter, *because output is determined by displacement*


Ok, let me rephrase my previous statements in your terms.

If I take four ND91s in parallel and apply 1.4V (1w nominal into 2 ohms), I will get half of the displacement (-6dB) than if I applied 2V (1w nominal into 4 ohms) to the 8 FE800. The shapes of their frequency responses over 80-1k is similar so that holds true at any frequency of interest. OTOH, if I want the same displacement from each setup, I need to apply 4x power to the ND91 array to get it up to speed.

Output limits on the device are governed by mechanical and thermal limits/behaviors. At low frequencies, the maximum mechanical excursion is sometimes the primary limiting factor, which I believe is what you are getting at. In this case, the 4x ND91 and the 8 FE 200 have similar maximum displacement. However, in my application this won't really be a factor - I don't intend on running them below 80-100 Hz and I'll only see max excursion if I put in a sine wave at 100 Hz and just blast it wide open. OTOH, thermal considerations do come into play. As a rough estimate I was thinking I'll see peaks of 115 dB and rms values of 100-105 dB from one mid when the system is cranked. The peak values aren't a huge concern although that would require a much larger amplifier on the array and dumping 100w for a fraction of a second into each little driver could burn the coils if I'm not careful. What concerns me more is putting ~10w in RMS... with that much power the 8 should see a small but negligible amount of power compression. The little drivers though would each need that much power to hit the same level and in my experience that is enough to get audible power compression from a driver/coil of that size. Unfortunately the Klippel report did not include the power compression data but I believe it would back me up.

There just isn't any reason to go with those drivers in this application. If you were arguing for something like the JBL GTi 6" midbass, I could understand. You trade off some sensitivity (~3 dB) but it fits into a smaller package, has slightly more max displacement, and a motor that can take power. There are some upsides there that might be worth the extra cost (in money and power).


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## Rybaudio

Regarding the CSS driver, do you realize the first distortion graph is at .5m? If the B&C test is at 1m, then there is a 6 dB offset, which is equivalent to comparing two CSS drivers perfectly summing vs. 1 B&C. Where did that B&C test come from? In any case, the distortion 500-1k (why are we concerned with just 1 octave?) in both of those graphs looks low and may simply be negligible. OTOH, at 100 Hz the CSS THD is -20 dB while the B&C is -45 dB. A 25 dB difference corresponds to ~400x power, so the distortion coming off of the CSS is 400x the intensity of what's coming off of the B&C. If they were both negligible, that wouldn't matter, but -20 dB is a concern, and for my application I'd want to get more peak output than 106 dB (4x CSS at that drive level).

Also, if I'm reading the Klippel correctly the CSS shows ~1.3 dB power compression with around 1w input. The report doesn't show watts but dB which is ~84 in the graph so I'm assuming it's normalized to 1m - if that's also at .5m that would mean .25w. If I read it right, putting 4 in parallel gets you 90 dB with 1.3 dB compression. What's going to happen when you put 10x power to get it up to 100 dB? It only takes 1-2 dB of compression to give an audible spectral tilt, and lowering 100-1k by 4-5 dB is quite bad.

Four of those drivers totals ~$200 so they lose from a cost perspective. None of this is surprising because they've been designed for a special purpose, which isn't covering 80-1k efficiently and cost effectively.


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## Patrick Bateman

Jesus Christ said:


> So how much power does it take to get one of your nd91's to hit xmax at 250hz? 500hz? Hint, you'll have melted the coil long before you get there.


Riddle me this:

Which has a larger voice coil:









1) The Faital 8FE200, a prosound 8" woofer, built for high power applications

or 









2) An array of four of the Dayton ND91s, a puny little 3" woofer, which appears to be something you'd use for some speakers that you give to your 14yr old niece to listen to Miley Cyrus in her room




I think the answer will surprise you:

It's the Dayton. Four of the Dayton ND91s have the equivalent of a 2" voice coil. Four of them have SEVENTY EIGHT PERCENT more surface area in their voice coil than the Faital.



In summary:

four of the ND91s have a voice coil that's equivalent to more than one and a half of the 8FE200s. I generally ignore power ratings and focus on voice coil diameter, because that's one of the largest determinants of power handling. I'm not about to do a power test, but my money is on an array of the ND91s
the displacement is about the same for both



I really appreciate all the feedback, I hope I made a few people stop and think about small driver arrays. I know that it might sound like I'm saying that their superior, *but I'm not.* To me, they're just another option, one of many. I am personally very opposed to modifying my cars; I don't tend to keep them for long. I've owned four cars in the last eight years.



So please don't mistake my suggestions for midbass arrays as a "I'm right / you're wrong" argument. It's more like "here's something to consider if you can't shoehorn an 8" wooofer into your door without modifying the car, or if you just want to try something different, or you're curious about distributed bass."


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## Jesus Christ

Patrick Bateman said:


> It's the Dayton. Four of the Dayton ND91s have the equivalent of a 2" voice coil. Four of them have SEVENTY EIGHT PERCENT more surface area in their voice coil than the Faital.


The point I'm trying to make is that a drivers displacement doesn't matter if it doesn't have the power handling to reach that displacement at a given frequency and the larger coil area is negated by having to dump 4x the power into them to reach the same output due to the lower sensitivity. Not saying arrays are bad, just that these drivers aren't the best choice.


----------



## Rybaudio

Even if 4x ND91s could handle more power, it doesn't matter, because it takes them 4x more power to hit a given output. What matters is what happens when you hold output the same between the single 8 and 4x ND91s, and turn the volume up. Given you are putting the same power into the 8 as you are into each ND91 if their outputs are the same, I would bet money the ND91s (1) show non-negligible power compression at a lower level, (2) show more power compression at any level, and (3) show thermal failure earlier. Now, if they have enough output before any of those effects set in, it doesn't matter. But if I interpreted the power compression curve on the Klippel report correctly, power compression sets in well below the levels I want out of the setup.

I can agree the arrays are an option in some cases, and it's certainly been illuminating going through the numbers. The suggestion someone made earlier with 2x 6.5 makes a lot of sense. That fits pretty well in the bottom of a door and if aligned horizontally has the same vertical dispersion as a single 6.5. Using 4 x 4" is an extension of that idea. I just think you'll have a hard time finding a 4" driver that does a good job performance wise, but that tradeoff might be worth it in some cases.


----------



## Rybaudio

Patrick Bateman said:


> I think the answer will surprise you:
> 
> It's the Dayton. Four of the Dayton ND91s have the equivalent of a 2" voice coil. Four of them have SEVENTY EIGHT PERCENT more surface area in their voice coil than the Faital.


I've been trying to figure out where you got that number from and I think I see it now. A circle with diameter 2" has an area that is 1.78x the area of a circle with diameter 1.5," but what does that have to do with surface area of a voice coil? The surface area of the coil should be 2 x circumference x depth. The 2x is for inside and outside and doesn't matter comparison wise.

A 2" coil has a circumference that is 1.33x that of a 1.5" coil, so the ND91s have the upper hand there. OTOH, the winding depth on the 8FE200 is 12 mm. The ND91 doesn't have a depth listed, but it does say it is underhung, so it's really unlikely it is close to 12 mm. Unless this uses some topology I'm not familiar with, the top plate would have to be near an inch thick. If the depth of the winding is less than 9 mm, which is not unlikely, then the ND91s' coils have less surface area.


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## Patrick Bateman

Rybaudio said:


> Even if 4x ND91s could handle more power, it doesn't matter, because it takes them 4x more power to hit a given output. What matters is what happens when you hold output the same between the single 8 and 4x ND91s, and turn the volume up. Given you are putting the same power into the 8 as you are into each ND91 if their outputs are the same, I would bet money the ND91s (1) show non-negligible power compression at a lower level, (2) show more power compression at any level, and (3) show thermal failure earlier. Now, if they have enough output before any of those effects set in, it doesn't matter. But if I interpreted the power compression curve on the Klippel report correctly, power compression sets in well below the levels I want out of the setup.
> 
> I can agree the arrays are an option in some cases, and it's certainly been illuminating going through the numbers. The suggestion someone made earlier with 2x 6.5 makes a lot of sense. That fits pretty well in the bottom of a door and if aligned horizontally has the same vertical dispersion as a single 6.5. Using 4 x 4" is an extension of that idea. I just think you'll have a hard time finding a 4" driver that does a good job performance wise, but that tradeoff might be worth it in some cases.


Dual sixes would be way less work.
In hindsight, I really really wanted to avoid chopping up my car, but a pair of sixes in the stock location aren't that much work to remove. The big problem becomes shoehorning eights and tens into stock locations.

(Ironically, my car has stock eights, but the depth is insanely shallow, like 1.5".)

Despite all this talk about displacement, I've found that the main problem with midbass arrays is that they take a freaken million years to build. I literally spent about a week building two of them. I spent more time building two midbasses then I spent building my subwoofer or my horns.

This is because the dimensions are so small, so it's a LOT of work to get everything to line up and fit. (Half my midbasses are under my seat, and I literally had about 1/4" of clearance. 3" was the absolute maximum size.)

I came close to losing my right thumb when I built some speakers this small a few years ago; these small enclosures aren't just difficult to build, they're dangerous. This time around, I built the enclosure mostly with hand tools because these small parts aren't safe to build with power tools IMHO


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## Patrick Bateman

Rybaudio said:


> I've been trying to figure out where you got that number from and I think I see it now. A circle with diameter 2" has an area that is 1.78x the area of a circle with diameter 1.5," but what does that have to do with surface area of a voice coil? The surface area of the coil should be 2 x circumference x depth. The 2x is for inside and outside and doesn't matter comparison wise.
> 
> A 2" coil has a circumference that is 1.33x that of a 1.5" coil, so the ND91s have the upper hand there. OTOH, the winding depth on the 8FE200 is 12 mm. The ND91 doesn't have a depth listed, but it does say it is underhung, so it's really unlikely it is close to 12 mm. Unless this uses some topology I'm not familiar with, the top plate would have to be near an inch thick. If the depth of the winding is less than 9 mm, which is not unlikely, then the ND91s' coils have less surface area.



















^^ note the depth of the two drivers








^^ cross section of their sub, chances are good their mids are set up the same way

Four ND91s definitely have more diamater than a single 8FE200, and I'd be willing to bet they're deeper too. All of the Aurasound drivers (and their clones) are built like subwoofers. Just look at the depth.


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## Rybaudio

That doesn't sound like a lot of fun (making small enclosures).

For my setup, I could do a 6.5 in the door under the stock grill and another 6.5 in the kick, but that might be too much separation to run both up to 1k, and if the resonances differ on the low end (from the different enclosures) they aren't going to sum well. The door could be lowpassed at 200-300 Hz but then I either need big inductors/caps or another amp/processor channel and in either case the phase shift around the crossover region might have some odd effects. I'd have to look closer at the specifics to see if it makes sense.

I think if I was considering 2 x 6.5 in the door itself, I'd rather just go with a single 8. 2x8 would probably be easier to fit than 1 x 10 though. For my application I think a single 8 will be enough output.

At this point the question is to do a 6.5 or 8, and which one. I can probably squeeze a 6.5 under the stock grill which would be nice. I might be able to squeeze an 8 under there with some cutting and maybe cheating a little by spacing the door panel out 1/4" on the bottom. If I'm gonna rebuild the bottom of the door panel it's going to be at least an 8.


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## Patrick Bateman

Rybaudio said:


> That doesn't sound like a lot of fun (making small enclosures).
> 
> For my setup, I could do a 6.5 in the door under the stock grill and another 6.5 in the kick, but that might be too much separation to run both up to 1k, and if the resonances differ on the low end (from the different enclosures) they aren't going to sum well. The door could be lowpassed at 200-300 Hz but then I either need big inductors/caps or another amp/processor channel and in either case the phase shift around the crossover region might have some odd effects. I'd have to look closer at the specifics to see if it makes sense.
> 
> I think if I was considering 2 x 6.5 in the door itself, I'd rather just go with a single 8. 2x8 would probably be easier to fit than 1 x 10 though. For my application I think a single 8 will be enough output.
> 
> At this point the question is to do a 6.5 or 8, and which one. I can probably squeeze a 6.5 under the stock grill which would be nice. I might be able to squeeze an 8 under there with some cutting and maybe cheating a little by spacing the door panel out 1/4" on the bottom. If I'm gonna rebuild the bottom of the door panel it's going to be at least an 8.


If you have the depth, you can easily 'route' the output of a 8" or even a 15" through a 6.5" hole. I can sim it in hornresp if you're curious. It changes the response, but it also lowers the distortion. If you have an 8" or a 10" that'll fit in a door, and you don't want to chop up your car, this mounting method can reduce distortion.

















Emerald Physics crams the output of a 15" woofer through a 6.5" hole. Seems kinda odd, but it works.


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## Rybaudio

I wouldn't be loading it anywhere near that extreme. The door panel has plastic under the grill that can be cut away to give a hole around 6.5" in diameter, which is about the effective diameter of the cone. So I figure as long as it fits underneath and I make sure nothing in the door panel resonates, it should perform pretty close to being just baffled.


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## thehatedguy

I just don't think you have the depth in the doors to do a nice 8 behind the factory panels and have the windows roll down all the way.

You might though...been a while since I messed with one of those cars.


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## jpeezy

the amount of work your going to do, to try and squeeze an eight in that door(not likely to fit anyway), the kicks in that car are fairly large, and you can route the rear wave through a channel in sill, or cut behind driver and vent outside.I actually used two dayton 5" mid bass stacked vertically in the kicks first,sounded good but nowhere the impact of an eight (eminence if i remember correctly). By putting the eights in the kicks you"ll also equalize the left-right distance between the two drivers far better than in the doors.good luck.


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## Rybaudio

Yeah I took another look at the door panel and there's no way a normal 8 will fit under the stock grill.

I was going to try avoid kicks but maybe pulling the panels out to have a look at the space will convince me otherwise. If I'm going to do some fabrication to get an 8 into the door I could just as well do kicks if they aren't obtrusive.

So there are some options still on the table... 

- 6.5s under stock door grill
- 8s in custom door panels
- 8s in kicks

I wouldn't mind keeping a stock look with a 6.5 in the door if I can get enough output... it just seems lame to put horns in and not at least 8s. The 6 FE200 loses a dB in the midband and rolls off earlier. If you ^ can fit 8s in the kicks with a clutch pedal, I can probably deal with the obstruction.

So the next question is mini vs. fullsize horns? If the full size do work and work well, are they the go-to option? How do the two compare?


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## thehatedguy

I would do the 8s in the kicks if they would go.

Minis would be easier to install, they'll have a little better treble since they are smaller, and probably a little better center since they have more of a crossfiring pattern.

But the big horns will let you play them lower making the aiming of the kickpanel pretty much a nonissue.

Me, I always liked horn loading as low as I could go.

But you might not like having your clutch foot that close to the horn.


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## Rybaudio

I have an auto so the clutch foot is not an issue - was more concerned with foot space and people kicking the passenger side.

How big is the difference on the low end? Are we talking like 800 vs. 1.2k?


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## thehatedguy

Yeah at the lower limits of the drivers Eric has.


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## Rybaudio

Dug around in there some more today... if I move the ECM/ABS modules from the passenger side there is a ton of room in the kicks - definitely doing 8s in the kicks. You might even be able to squeeze 10s in there but I'm not going to push it. The plan is to put the horns in and move the ECM at the same time and then build the kicks. Some questions:

- the ECM is held in the factory spot in kind of a funny way. The chassis has feet on both sides. On one side the feet are insulated by rubber boots, but on the other side one of the feet is bolted directly to ground. Are the rubber boots just for mounting purposes? I'm guessing it will work ok if I just move the mounting bracket for the insulated feet over to the new location and make a solid ground with the foot that is grounded now (I think that's what jpeezy said in one of the first posts in the thread), but I figured I'd throw it out there to see if there is anything I should be concerned about.

- Anyone have any experience with the Faital 8FE200? Any other 8s worth considering?

- What's the best way to get in touch with Eric? I tried PMing him a few days ago but haven't received a response.


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## thehatedguy

In my Accord, I just unbolted it and flipped it over on the TCM...there was enough wire there to do that without having to extend anything. But I don't recall if the bolts were for ground purposes or just to secure it.

Lots of great 8s, just depends on your budget. My 2 favorites would be the JBL 2118h and the BMS 8S215. The Beyma 8G40 was highly recommended to me too, and a few folks around here have picked them up...come in 4 ohms too. 18Sound has a couple nice 8s. B&C is solid too.

But the JBL and BMS are my top picks.


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## Eric Stevens

Rybaudio, you have a response to your pm. Sorry I thought I had responded as I usually respond right away so I won't forget when I get busy.


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## Patrick Bateman

thehatedguy said:


> In my Accord, I just unbolted it and flipped it over on the TCM...there was enough wire there to do that without having to extend anything. But I don't recall if the bolts were for ground purposes or just to secure it.
> 
> Lots of great 8s, just depends on your budget. My 2 favorites would be the JBL 2118h and the BMS 8S215. The Beyma 8G40 was highly recommended to me too, and a few folks around here have picked them up...come in 4 ohms too. 18Sound has a couple nice 8s. B&C is solid too.
> 
> But the JBL and BMS are my top picks.


Friends don't let friends use Faital.

OK, maybe that's a little harsh.

The B&C drivers are "only" about $105 and have a lot of features that the Faitals don't. Larger voice coils, treatment on the cone, etc.

The Faital reminds me of all the things I hate about cheap prosound drivers. Untreated cones, a voice coil that belongs on a 5" driver, basic motor topology, etc.

If you look at the graph on the Faital, it's on a scale of a hundred(!) decibels, which makes all the wiggles and hash in the response look OK


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## jpeezy

Actually Faital pro's cone are treated for water or moisture resistance. Fortunately consumers from all walks of life are involved in audio, and car audio as well. Unfortunately not all of us are as fiscally gifted as some consumers out there, so we are just as happy with our 45$/ mid bass pro sound drivers . Thanks.


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## Rybaudio

Spent some time looking through the options... there are definitely some nice drivers out there. Anything that fits my application fits basically has to do around 95 dB 1w/1m half space sensitivity, at least 4 mm xmax, and has parameters that make it usable in a smallish sealed box. There are a lot of options that fit that.

The Faital 8FE200 gets the job done but has a 1.5" coil. The other drivers cost about 3x as much, but they have 2" or 2.5" coils, so they can probably take a little more power before compression and more power overall. In my case I think it's unlikely I'd ever be driving one mid alone past 105 dB rms or 115 dB peak, and most of the time it'll be a lot less than that. Peak power handling won't be an issue, so the question is will I see negligible power compression putting 5-10 W rms into the Faital? At the upper end of that it will probably start to creep in (like 1-2 dB at most) but that's cranking it wide open continuously. Under normal conditions it should be negligible. In different conditions, like in home speaker playing over a wider bandwidth (say 60-2k) and being further away from you it might be worth the extra coil, but I can't justify on those grounds here.

The midrange is a little unknown, but I'm going to be running this thing up to 1 kHz, so I don't think that will be an issue. The B&C drivers are pretty bad ass in the midrange - I've used a few of their drivers in home speakers and they tend to measure and sound good. If I needed it to go higher I'd probably use one of the B&C 8s.

Another big downfall to a lot of these is the impedance. It seems like you end up wasting a lot of amp with 4 ohm speakers the way it is since most can run 2 ohm stereo. 8 ohm drivers just make it worse. The Beyma is nice because you can get it in 4 ohms, but it's over 3x the cost and I can't find any data on the 4 ohm model. As far as I can tell it isn't even listed on their website.

About 98% sure I'm going to just pull the trigger and go with the 8FE200s... will sleep on it and order them tomorrow.


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## jpeezy

i think you'll be pretty happy with them, especially at the price point. US Speaker i believe carries both the 4ohm and 8ohm. Good Luck.


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## thehatedguy

DSL uses a lot of Faital cone drivers, and B&C coaxes, and BMS compression drivers.



Patrick Bateman said:


> Friends don't let friends use Faital.
> 
> OK, maybe that's a little harsh.
> 
> The B&C drivers are "only" about $105 and have a lot of features that the Faitals don't. Larger voice coils, treatment on the cone, etc.
> 
> The Faital reminds me of all the things I hate about cheap prosound drivers. Untreated cones, a voice coil that belongs on a 5" driver, basic motor topology, etc.
> 
> If you look at the graph on the Faital, it's on a scale of a hundred(!) decibels, which makes all the wiggles and hash in the response look OK


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## thehatedguy

Parts Express also has Faital Pro. $2 more and you get free shipping from PE.


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## fenis

I've been very happy with my 10FE200's! They are playing up to 1k with my horns and are receiving 200wrms (8 ohms) each. Their peak power rating is 300w.

With my slight downtilting house curve and +12db of bass relative to the midrange they probably only ever see the full 200w on peaks of music even when I'm listening at very loud volumes (110dBA on an SPL meter is VERY loud and pretty much like front row at a concert). So you are right, the more expensive drivers that can handle 500w+ aren't necessary in a car, especially considering most people like to run their subbass 10dB+ hotter than the midrange.


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## Rybaudio

I did end up ordering the 8 FE200s and full size pro horns. They should be here next week some time and I can start putting them in.

A couple days ago I also pulled out some measurement gear I used to use. I have a woofer tester 3 that I'll use for impedance (and maybe T/S) and a Behringer ECM8000 + preamp + TrueRTA for basic acoustic measurements. None of it is great but I already have it and it'll work. The mic is not calibrated so it has unknown behavior on the ends but I figure the bass levels and any spectral tilt on the top end will probably be tuned in by ear anyway.


For processing I'm thinking the miniDSP 2x8. That will do what I want at a decent price and it has enough flexibility that I can use it in virtually any home or car system I'd do later. A pair of 2x4s would probably get the job done for about 2/3 the cost, but then I have to chose balanced or unbalanced and there's a decent chance I'd want to use the other down the line.

Has anyone reading used the miniDSP? Known issues? In/out voltages seem somewhat low but workable. Are there comparable options around that price point?

The head unit situation is a bit of an unknown... I'm definitely a dinosaur in that regard - the last car system I put in used a CD player only (a Rockford RFX-8140 I bought from THG close to 15 years ago!) and I have never used an ipod or mp3 player in car. Hell I just got my first smart phone 2 months ago. For home audio I use a big collection (~380 GB) of high bitrate mp3s and taking some of that into the car would be nice, but I don't know how navigating through folder structures would work while driving. If that is doable then I really have no need for a CD player.

Just browsing around on crotchfield there appear to be a number of inexpensive digital media receivers available. Any suggestions? Do any decks have decent built in processing? I like the idea of a very basic head unit with the processing basically set and forget (like the miniDSP) but if it makes sense I could go all in one.


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## thehatedguy

The best (IMO) deck that has processing, all of the modern features, and doesn't break the bank is the Pioneer DEH-80PRS.

You still have the 8140?


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## Rybaudio

I still have it! It hasn't been hooked up in close to 10 years but I take it out to have a peak every now and then.


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## Rybaudio

Updates:

- Installed the horns last weekend - took quite a while but they are in pretty solid and aligned fairly well with the bottom of the dash. I'll probably play with the way the top is mated to the dash after the system gets up and running. The passenger side is slightly lower than the drivers side but there's not a whole lot that can be done - maybe drop the drivers side a bit and fill the gap in with something but I don't know if it's worth it.

- Faital 8s arrived and they're pretty close to spec as far as basic t/s parameters go. Going to make kicks either starting during the week or over next weekend - very glad I waited until the horns are in because the back of the horn takes up some space.

- After looking at a bunch of amp options I picked up a PPI P900.5 for the whole system. If it holds to spec, it'll do 70x4 + 400x1, is fairly efficient, fits under my passenger seat with ease, and cost $230 to my door.

- A few weekends ago I took some LF measurements in the car to see the transfer function for various configurations. Tried sub pointed back/sideways/forward, seat up/down, windows up/down, moonroof open, etc. to get a feel for how each of these things affect the bass and also how much output I need to design for. I referenced everything to 1m ground plane which is equivalent to what winISD spits out at LF. The car has around 25 dB gain (again relative to 1m half space) at 20 Hz, 20 dB gain at 30 Hz, and kind of tapers down to 0 dB up around 80 Hz. I figure I need 125-130 dB in the bass so I can work back from there. I might end up using a couple JBL car subs that were in my home system but haven't been used in a while. For the time being, I'll just drop one of them in the trunk in its existing enclosure to see if that's enough.

- A pair of miniDSP 2x4 unbalanced kits (+volume pot and miniDC) are on the way - pretty good deal at less than $200 shipped for the whole lot.

- I'm actually going to use my phone as the primary source, at least for now. The miniDSP volume pot can control both units. So basically I get my dream head unit - blank panel with a big ass volume knob and a power button, and a touch screen to control the material. Every HU I looked at was either way too expensive or god awful to look at or use. A couple, like the DEH-P80RS aren't too bad, but I could not find anything that had the exact processing I'm looking for.


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## estione

Have you cut the horns diagonally?


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## Rybaudio

They are the same overall shape as when I got them. I trimmed some of back of the body off the passenger side and in a couple other places to make them fit but otherwise they are fully intact. The front face goes all the way across to behind the center console.


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## Patrick Bateman

Rybaudio said:


> Updates:
> 
> - Installed the horns last weekend - took quite a while but they are in pretty solid and aligned fairly well with the bottom of the dash. I'll probably play with the way the top is mated to the dash after the system gets up and running. The passenger side is slightly lower than the drivers side but there's not a whole lot that can be done - maybe drop the drivers side a bit and fill the gap in with something but I don't know if it's worth it.
> 
> - Faital 8s arrived and they're pretty close to spec as far as basic t/s parameters go. Going to make kicks either starting during the week or over next weekend - very glad I waited until the horns are in because the back of the horn takes up some space.
> 
> - After looking at a bunch of amp options I picked up a PPI P900.5 for the whole system. If it holds to spec, it'll do 70x4 + 400x1, is fairly efficient, fits under my passenger seat with ease, and cost $230 to my door.
> 
> - A few weekends ago I took some LF measurements in the car to see the transfer function for various configurations. Tried sub pointed back/sideways/forward, seat up/down, windows up/down, moonroof open, etc. to get a feel for how each of these things affect the bass and also how much output I need to design for. I referenced everything to 1m ground plane which is equivalent to what winISD spits out at LF. The car has around 25 dB gain (again relative to 1m half space) at 20 Hz, 20 dB gain at 30 Hz, and kind of tapers down to 0 dB up around 80 Hz. I figure I need 125-130 dB in the bass so I can work back from there. I might end up using a couple JBL car subs that were in my home system but haven't been used in a while. For the time being, I'll just drop one of them in the trunk in its existing enclosure to see if that's enough.
> 
> - A pair of miniDSP 2x4 unbalanced kits (+volume pot and miniDC) are on the way - pretty good deal at less than $200 shipped for the whole lot.
> 
> - I'm actually going to use my phone as the primary source, at least for now. The miniDSP volume pot can control both units. So basically I get my dream head unit - blank panel with a big ass volume knob and a power button, and a touch screen to control the material. Every HU I looked at was either way too expensive or god awful to look at or use. A couple, like the DEH-P80RS aren't too bad, but I could not find anything that had the exact processing I'm looking for.


It might be wise to spend two bucks on a potentiometer. IIRC, miniDSP does attenuation digitally. So when you turn down the volume, you lose resolution and increase the signal to noise ratio.

Basically an analog volume control might be better.

In all other respects, I <3 my miniDSPs. I have two of them, and I also bought their Ambio4you processor.


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## Rybaudio

I bought the pot they sell with the kit. That is what I am planning to use for volume. Is that what you mean or are you referring to something downstream from the miniDSP?


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## P_4SPL

*Sound compression comes from the source, the music!

* Music isn't engineered to sound good on your $400 speakers, it's not even engineered to sound good on $10,000 worth of equipment> it's mostly a Sine Wave thats all, compression kicks in because on a pair of 3" drivers located on your desktop or OEM car radio system...it sounds good! Thats how it's engineered to sound quick and easy.

Not many people notice how music looks like anymore, the signal IMO is supposed to have fluffy peaks and dips / (Spikes) these spikes represent voltage (Left channel - Right Channel) when you see a flat signal with no peaks or dips (like voltage spikes) then it basically behaves like a Sine wave.

*Your speakers need the input voltage (music signal) to have peaks and dips> these peaks and dips cause the speaker to start...then stop> this start then stop allows the speaker to come to a rest, if it doesn't then the speakers is always in the Extended position, producing too many freq's at once without coming to a stop, thus increasing heat, and then compression, I would say it would take a speaker ms's to reach compression with this type of music.

The only solution to this would be IMHO to re-master the music, ad some range compression -3db to -8db, whatever gets the signal to have those peaks and dips> I can tell you music that has no peaks and dips in it will benefit from this type of range compression, it actually clears up the music (finitly that is) because range compression ads a ms or 2 of delay, this ms delay is the delay between peaks and dips, the slight delay in voltage actually IMO allows the Amps input to Absorb it and interpret the voltage to the mosfets more acuratlely before sending it to the speakers, (Although adding too much delay can come out with some unwanted reverb in the music) none the less, it definatly clears up the sound when it's done minutely. As well I reduce the amplitude of the entire track -1 to -3db> that way it never reaches levels that could be dangerous to your drivers.

Owning a pair of Veritas compression drivers (with Radian B950's) I understand well that tiny peaks in freqy from the input signal are magnified 10 times when played back through those drivers, it's taken a while for me to actually understand this phenomenom, basically music that sounds good with a desktop tweeter, or any 1" dome tweeter will have much more audible compression issues on the larger 2-3" diaphram most horns have, or at least relfected waves inside the horn body will be that much larger than the tiny dispersed freq's of a 1" tweeter metal or fabric.

* After applying dynamic range to the entire signal (if it's not as peaky) I then run the Track through a Multi band range compressor>I Pull back freq's between 10khz-20khz Then 2000khz-10khz then 120hz-2000hz then some 0-120hz (0-120hz is another phenomenom of recorded music, for some bass heavy music tracks they overshoot the sub freq's to make them Louder at lower volumes, this works well under normal volumes ...but as I found out at louder volumes it can blow out subs). Range compression can remove alot of those High Freqy peaks, it actually dulls their output, but Horns efficiancy can reproduce those subtle freq's more coherently and audibly sounds better to your ears.

*It's unfortunate that music is no longer engineered to sound spectacular on good equipment. And resorting to re-tweaking the music itself is the only option (at least in an automotive environment) to make it sound good and tolerable.


----------



## P_4SPL

* I forgot to mention most importantly, that all music is clipped, which is why I either apply range or reduce amplitude of the track.


The top signal is clipped 

Reducing the amplitude -1db removes clipping from the signal.








*Note: Although the above example is of Bass Heavy Music tracks, I could find hundreds of recording artists music that have the music signal clipped.


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## rockin

Its so weird you posted this. I listen to the same material on horns in my car and direct radiating speakers in my house. Now, I have noticed a lot of differences, sure they are 2 totally different setups, but I notice a lot of difference even between different recordings. That led me to wonder if it was in fact differences in recording. So I wanted to make some recordings of my own and experiment, although I had no idea the look of music had changed. When did it change roughly? Any idea? Also, if that is the case is it possible to obtain some older material prior to the change to listen to for a reference? 
Any suggestions?
Are you a recording engineer? I was going to buy 
"Modern Recording Techniques v8" by Huber and Runstein
to get a little education before I started my experiment. Do you know if that is a good book for reference?


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## JoshHefnerX

I noticed this about 10 years ago, but it started before that. I think the worst offender is Metallica's Death Magnetic. google loudness wars.


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## P_4SPL

* I assume it happened after 2000 when music and mp3 became more popular.

I had some CD's I used to listen to back in the 90's on my previous Car Stereo, I remember I could Crank up the music full blast and never hear audible distortion, when I started to get back into stereos after a 10 year haitus , I started to notice music on my new rig would sound harsh and distorted, music such as Dilerium, Moby etc... New CD's, ...I ended up ripping the tracks that sounded bad and saw that from a brand new disc the music was clipping? It was burnt and the signal was running very hot, Monster Magnet is another CD that was recorded hot with no peaks or dips.

I then checked my older Techno CD's I used to bump to and found that they where all recorded with up to -3db amplitude signal + No Clipping!! The signal itself had lots of peaks and Valleys, which shows it was mastered very well.

* I would try riping an older CD previous 2000, and see how the signal looks.

*It's too bad that music is done this way, without regard for us who have $1000's invested in expensive equipment, me included (NAD , Paradigm, Velodyne Home Theatre system), Playing back those clipped tracks MIGHT sound normal to your ears, but have you seen how many people complain their subs can't handle a certain scene in a movie or a Music CD, it's because the music is Clipped> I've seen Brand New bluary Movie audio tracks that have the audio clipped!

Basically IMO your risking your good equipment playing back this JUNKY distorted sound recording on your HiFi equipment, it can be tricky to notice the difference since larger speakers can mask this effect, but the bottom line is it's still is there no matter what it sounds like, pushing speakers with clipping is intended to add High Freq's and a sense of fidelity from the speakers, something that your ears can interpret very well, unfortunatly can eventually cause listeners fatigue , which IMO is why most speakers come with copper inserted in them to cancel those compression artifacts.

Quote:
More accurately, what is being described is a "Faraday ring" or flux modulation suppression ring. It forms a 'secondary' winding with the pole piece as the magnetic core and the voice coil as the primary winding of a 'transformer'. Shorting the secondary winding with the copper ring has the effect of reducing 2nd harmonic distortion in drivers that use ferrite or ceramic magnets.

I'm not a music engineer, I just enjoy music as a hobby.


Doing listening test's with good and bad tracks can be tricky, but it mostly comes down to theory and the base on which music was created for> proper signal to be picked up by an amplifier and sent to a speaker then to your ears.


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## P_4SPL

* Currently I'm experimenting with compression techniques.

When I apply multiband compression it lowers the overall amplituted of the signal> my aim is to keep the amplitude -2db to -3 range.

The tracks I've compressed so far sound good on the drivers, no clipping or distortion at loud volumes, the small issue is volume is slightly lower @ -3.4 to -4.2 amplitude.

From my understanding, diluting the Peaky high freq's and other freq's should remove them completely (remove those fine harsh peaks that sit statically on speaker cones), I'm re-adjusting the peak amplitudes of those tracks to -2 -3db, and see if the volume is louder without those peaky harsh freq's.

* I imagine music engineers that work with Horn drivers at large concert venues apply TONS of compression on those horns, if they didn't your ears would bleed out before the concert was over, there definatley has to be some sort of adjustment done to those types of drivers.


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## JoshHefnerX

Does knocking that amplitude down cause the peaks to be square waves - because the data was "chopped", or are you able to do something w/ that?

Josh


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## P_4SPL

* I believe square waves occur only when there's clipping in the signal> basically amplitudes that go above 0db @ +1 +2 is distortion, but...tiny speakers with no resolution capabilities, the extra +2 db comes out sounding more like better pronounced high's.

I would say I'm not really chopping the sound, I'm attenuating it, from what I've experimented with, cutting back removes the harshness, if there is any, Waveguides can amplify tiny amounts of harshness, and bring it to rediculous levels inside the car when the volume is turned up.


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