Here is the future system for out project corvette:
http://www.hometheaterhifi.com/volum...o-12-2002.html

Head Unit:
Alpine IVA-D900 (DVD,MP3, 7" Screen, Fiber output to H700)
Processor:
Alpine PXA-H700 (Dolby Digital, Prologic II, 31bandx8channel EQ, DTS, Crossover, 8channel time correction to .5")

Amplifiers:
McIntosh MCC82 (1x100RMS@.005THD) [Front Center]
McIntosh MCC404 (4x100RMS@.005THD) [Front L/R, Surround L/R]
JL Audio 1000/1 (1x1000RMS@.05THD {5-500Hz}) [Sub]

Speakers:
DynAudio System 360 (8",3",1.1") [Front L/R]
DynAudio System 220MKII (5.75",1.1") [Surround L/R]
DynAudio MD100 and MD140 (1.1", 3") [Center]
JL Audio 12W7 Subwofer

Navigation:
Alpine NVE-N852A (DVD based in Car)
MP3:
Included in Main Head
DVD Player:
Included in Main Head
CD Changer:
Alpine CHA-S634 (6disc,MP3, Fiber Out to H700)
DVD Changer:
Alpine DHA-S680 (5disc, Fiber out to H700)
Sattelite Radio:
Alpine TUA-T021XM (XM tuner via AI-Net)


Wiring will be via JL's Xsys system.


So.. that's the plan...

Am I overlooking anything? ;)

Brian Weatherhead
Car Audio Editor
Secrets of Home Theater and High Fidelity
http://www.hometheaterhifi.com


[Modified by brianw21, 8:57 PM 1/17/2003]

 

:eek: Your gonna add like 150lbs to the vette! What do you intend to use for alternator/alternators?

 

Yeah ... but it will sound great ...

TV Tuner :lol:???


[Modified by AP, 7:36 PM 1/17/2003]

 

rear speaker information is missing for the DTS decoding..........use the rear speakers and mount a sub in the well to maintain proper imaging for the 5.1 and 6.1 decoding. What is the output voltage of the head, anything less than 4 volts will yield poor signal to noise ratio (line driver may be required). What about signal cables? Double, triple shielded? Alternator upgrade, battery upgrade? System cooling (fans)?

kitt

 

I think when he say's "surround speakers" he mean's rears ...

 

Never heard it called that but ok..... :lol:

 

A Hairy Buttoxed alarm wouldn't hurt. This would be the time to do it when the car's ripped apart. You can get all the goodies on it and put them in wierd spots. :yesnod:

BTW, Nice setup! :thumbs:

 

I'm assuming the Xsys wiring is all twisted pair. A shielded twisted pair is the best way to go for noise rejection. Double or triple shielding is really a waste, it doesn't affect noise rejection significantly. Just make sure that when you ground the shield, only ground it at one end.

Sounds like a really sweet system...

 

That is gonna be one hell of a system. :yesnod:

 

Hope ypu don't make another "Flashing Christmas Tree". :cheers:

 

So I did the tests on the stock system over the weekend.... ughhh. What the hell did them make us pay for?

Tests:
1. System THD @100db (1khz, 500hz, 5khz, 10khz)
2. Amplifier output
3. IMD Distortion @100db

needless to say, it sucked...

So... I put a spiral gel cell in this weekend. Made by optima sold by schucks.. anyhow..

Speaker placement: (Mental notes, am I wrong here?)

1. Off Axis: Above 2500Hz the beaming effect causes response to change significantly if the included angle to the listener is over 10degrees. This means that tweeters should be aimed at a central point between the passenger and driver if at all possible, to reduce the included angle for both listeners.

2. Placement: The optimal placement is to have equal path lenghts from the left and to the right. The close this ratio is to 1:1 the better. This is the reason that kick panels are so popular. Un equal path lenghts create two problems:

a. Delay: Different distances cause the sounds to arrive at different times
b. DB: Different distances cause the sounds to differ in DB due to proximity.

So obviously kicks are a very good solution. Another solution is signal processing. Delaying the closest speaker to match the farthest. This is great for the driver, but makes it worse for the passenger. This is the only solution to this problem without kicks. DB differences can be adjusted by gain, but again, changes benefit the driver and impact the passenger.


This is also the reason for keeping the tweeter and midrange eqidistant, as the farther they are appart, the less they sound like one source.

Plan:

Place the tweeters in the factory locations angled towards the roofline between the driver and passenger. Place the mid close to the tweeter, pointed the same direction. Woffer, place the mid-bass in the stock 8" location firing into the foot wells.

I really like the idea of placing the tweets on the A-pillars, but sicne they are so close to the driver, and so far from the mid. I can't see where it would sound good.

Suggestions on placement?

Brian


[Modified by brianw21, 5:36 PM 1/20/2003]

 

Instead of aiming each tweeter at a central point, aim each tweeter at the opposite person's head (i.e. aim the passenger side tweeter at the driver's head and vice versa). This takes care of the dB difference because you're on axis with the farther one and slightly off axis with the nearer one. I also had a lot of success mounting my tweeters at the top of the door towards the front. They're close to the midrange, and aren't blocked by anything. Mine aren't in a vette, but I think in a vette the axis of the driver side tweeter should still clear the steering column.

Running as much power as this system will pull will probably require at least a capacitor and possibly a high-output alternator.

As for signal processing, what it will let you do is move the "sweet spot" of the system around. You can either put it right on the driver's head, or place it in the middle of the car between the driver and passenger. One thing that you'll find is that a car is such a small space that you get a lot of reflections and the sweet spot will never be "perfect." This is especially true in a vette with all the glass everywhere.

 

Right, I see where aiming them like that would help levels, but It would make off axis response worse on each side.

Brian

 

Yes and no. It's going to take some time and effort to aim them to get them just right. You maybe surprised with the end result. I'm sure you got a few good ears around that place to get it set up good! :D

 

Any new info on how the project is coming along?

 

The second article should be published shortly.

Update: The design is done, the equipment is on it's way. Sound Dampening should land next week.

Headunit: Alpine D900 7" (DVD/MP3/CD player)
Processor: Alpine H700 (PL II, DD 5.1)
Radio: XM
Changer: Alpine 6 Disc w/ MP3

Main Power Amp: McIntosh MCC404 (100x4 .0005 THD)
Sub Amp: JL 1000/1 (1200watts@12.0V)

Main Speakers: DynAudio System 360
Surround Speakers: DynAudio System MKII
Center Speaker: Dyn Audio 1",3" custom cross.
Sub: JL 12W7

Cabling/Power: Maple Audio http://www.mapleaudio.com


All is shpping or being shipped as I type... !

-Brian