E30 Audio Overhaul - My Project Details

[cobraken]

Do you have a reason you went with SB Acoustics?

[cobraken]

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[TurboFox93]

Please excuse my ignorance, can you please post pictures when it comes time to connect the CD43. I am not quite sure how you splice the speaker outputs from the CD43 into Audio Control unit. I'm assuming you have to integrate a male RCA connector onto the end of the - outputs of the CD43?? I know this has been talked about in multiple threads but I am having a hard time visualizing how/where to make these connections.

[bmwman91]

Do you have a reason you went with SB Acoustics?

Absolutely. "Car audio" speaker brands are, IMHO, 95% dog poop. The ridiculous amount of money you have to spend just to get a driver with a cast aluminum frame (versus stamped steel) is outrageous. On top of that, a great many of the major names in the industry make speakers with decorative cone shapes that look cool. This has zero basis in functionality, and probably causes even more distortion. The best speakers are usually the most boring looking ones. Basically, car-audio branded stuff if a bad value in my book. You cannot get output curves for the majority of them, which is sketchy and makes it hard to design the system. You DO need to be mindful of the environment you are placing speakers in, though. Moisture is an issue in a car, so you do want treated cones. Car-branded stuff seems to at least have this, and that's why so many have poly cones.

I was first introduced to the world of audio in ~2000 (high school) when a friend sold me his sub enclosure with 2x12" Rockford Fosgate Punch drivers. I installed various car-brand stuff (Sony Xplod, Blaupunkt deck, etc). I didn't know why, but it was pretty obvious that one needed at least 500W and big speakers to get good sound. A head unit that can do 200W (50Wx4) was pretty good to drive the 4 coaxial cabin speakers. I sold the stuff a couple years later when I was in college & got into autoX, but I was left with the knowledge that you needed hundreds of watts & big-name equipment to get a good system.

In maybe 2005 or 2006 a friend in college got into speaker building. He made some back-loaded horns with some Fostex drivers and built a 1W tube kit-amp. I could NOT believe what I heard. From 1W, I almost went deaf, AND the drivers he used were only like $50 each (very nice full-range 4" drivers) and had paper cones (which I had previously thought to be bad since, you know, it is "just" paper). The sound quality was above and beyond anything I had heard before. He later built a subwoofer that had to be strapped to the wall to avoid walking all over, and damn near got him evicted from the dorm he was living in. Once again, the total cost was mind-bogglingly low, and it did this with only 50W peak.

So, his projects brought me into reality. I have built some over-the-top speakers for my home theater since then and I am applying what I have learned to the car's audio system. SB Acoustics is very well priced, and they have all of their data sheets available, like any reputable brand should. Basically, their drivers can compete with ones that cost 4X as much in terms of construction quality, consistency & harmonic distortion (it has been measured and documented over at www.zaphaudio.com ). Browse through www.madisound.com to see some fun stuff. It is all overwhelming at first, and you'll probably feel like WTF at the selection of speakers priced from $3 to $6000 (yes, for individual drivers). As long as you aren't putting untreated paper cones into your doors / foot-wells, you are fine using "non-car" brands.

Please excuse my ignorance, can you please post pictures when it comes time to connect the CD43. I am not quite sure how you splice the speaker outputs from the CD43 into Audio Control unit. I'm assuming you have to integrate a male RCA connector onto the end of the - outputs of the CD43?? I know this has been talked about in multiple threads but I am having a hard time visualizing how/where to make these connections.

You can run either the + or - output of each channel to the 6XS. Read my breakdown of the CD43 here:

http://www.r3vlimited.com/board/showthread.php?t=170952

As long as you run one of those (it really doesn't matter which) to the + terminal on an RCA plug and connect the - terminal to the chassis ground, you are fine. One thing you can do to improve on that is to use the Audio Control level converter. that will accept the differential signal & then feed a ground-referenced signal to the 6XS. The advantage there is that you can run the diff signal all the way to the trunk which will greatly help to reduce noise if that is an issue, and then run a minimal distance of unbalanced signal from the converter to the 6XS. I am thinking that it won't be necessary, but I will do that if I get lots of alternator or ignition noise somehow.

[StereoInstaller1]

Thank god, another convert.

When I look at a JL woofer and I see stamped steel frame, 2" voice coil and a foam surround on a tupperware cone, I think "good $100 woofer" and then I see the price is like $250...its like WHY do people buy into the marketing?

There are PLENTY is issues running "home audio" speakers vs. "car" drivers, but most of the issue is warranty, which is virtually nil. As a hobbyist, that is all fine and good, but as a shop the liability is just too high. Too many retards who have NFC on tuning, crossovers, enclosure design...basically, nothing.

I have converted a few shops over to the concept of selling home drivers for car installation, but you need fairly deep knowledge of the product and how to sell a product with no warranty...basically. You can either build in enough profit to cover a replacement or two, or simply tell the customer they get to cover the cost of replacement BEFORE they buy them (good luck getting a salesman to actually cover the fine print on that one) so when they blew them up (as they always do), no one is screaming (as they always do) that "no one told me nothing about no warranty!"(as they always do).

So maybe that would explain why most people have never heard of the "good stuff"...Dynaudio, Morel, Scan Speak, Peerless, Vifa, Audax...or exotic stuff like Aurum Cantus or Bohlender/Graebener, or the new wave of terrific Chinese made product.

To me, developing a good understanding of this process is why I always look for the differences between engineering and marketing. I have no problem paying for engineering, but I really don't like paying a salesmans wages.

[StereoInstaller1]

Oh yeah, those SBA drivers are badass. You have to spend SERIOUS coin ($450+/set retail) to get that range of driver quality, generally more. I am not all that excited about the woofer, but it should fit his (the OPs) needs pretty well.

[bmwman91]

Oh yeah, those SBA drivers are badass. You have to spend SERIOUS coin ($450+/set retail) to get that range of driver quality, generally more. I am not all that excited about the woofer, but it should fit his (the OPs) needs pretty well.

Not that excited about the 10" sub? It has a much smoother response curve than the SP10 & WQ1858, and is considerably more sensitive. Those were definite pluses. Normally I am weary of "low profile' stuff, but this driver seemed to be legit. It IS freaking ugly though, I'll give you that. It's going to be hidden behind a grill & some speaker cloth.

Really, the only item I really feel like I compromised a lot on is the amp. I just cannot justify dropping the necessary coin to get Zapco stuff (which seems to be legit). The car is such a noisy environment that I know it would be wasted money at this point. As much as a no-compromises approach is tempting, putting audio equipment into a car is a compromise to start!

[reelop19]

Did you figure out how you're going to mount the front speakers yet?

[bmwman91]

Did you figure out how you're going to mount the front speakers yet?

I am 99% sure that I can buy myself the extra 3-5mm I need with a mallet & a wooden dowel. I can also yank out the Damplifier I installed & get 2-3mm that way. Spacers are a definite no-no since the woofer flanges & surrounds stick out almost 15mm. I will machine up some nylon or Delrin spacers to push the screw heads out so that the kick panels are up against those and not the rubber surrounds.

[StereoInstaller1]

150 grams of moving mass, a Qts of .4 and a Fs of 22Hz, with a sensitivity of 82db/W/M and a power handling of 200 watts? Not in my car, no thanks. Ain't ever gonna make the kind of bass I expect. Yeah, it will sound OK, but you are never gonna get the wallop I demand, especially in an airspace like that.


Their 15" driver looks OK though.

[5Toes]

So any woofer made without a paper cone is fine for car use?

Awesome. These seem amazing... http://www.parts-express.com/pe/show...umber=264-1096

[bmwman91]

150 grams of moving mass, a Qts of .4 and a Fs of 22Hz, with a sensitivity of 82db/W/M and a power handling of 200 watts? Not in my car, no thanks. Ain't ever gonna make the kind of bass I expect. Yeah, it will sound OK, but you are never gonna get the wallop I demand, especially in an airspace like that.


Their 15" driver looks OK though.

Fair enough. The response curve puts the frequencies I am interested in at 84-86dB, which is why they amp is rated to supply ~4X the power to the sub than it does to the other speakers (90dB sensitivity). If this thing is really disappointing, which it might be, then I will either swap it for something else or suck it up & build a box for it. I'll take your word for it that it won't kick like a bronco on coke.

[StereoInstaller1]

nope, no cocaine. Should make wonderful clean bass though, I would just rather see a Qts somewhere around .7 for what you are doing, maybe a Fs more like 28hz

[reelop19]

Wait, all this work and you're keeping the speakers in the kick panel? Come on man go with something in the door.

[Jean]

As mentioned, most (but not all) home audio drivers are 8ohms vs 4/2ohm and lower sensitivity. Other than that, you can still find some nice drivers for the money but I would never install my scanspeaks or vifas/seas/peerless in a car... they belong in a nicer home environment for longer / better use. imho .