natemoran

I just bought a 1989 S4 and am planning on installing a CD player this weekend. I am planning on removing the stock amp and wiring direct to new MB Quarts. Is there a constant power wire for the receiver near the mount; if not what is the best way to get constant power to the new receiver? (I have heard the memory power is fed back through the amp). Thanks in advance for any help - I've searched many threads and can't find the answer.

MikeN

Having a hard time remembering.......but there is a circuit (constant?) that runs through the amp that provides power to the radio. After removing the amp, all you have to do is build a small jumper wire with two spade connectors to bridge the circuit on the power supply plug to the amp. I believe you must jumper the large red cable/wire on the amp plug to the small red wire on the same plug. Again, look at it closely as I'm sure of the process, but not sure of the exact color codes, etc.......it's been a while!

dr bob

It is a red-to-red connection at the amplifier power connector. This is not shown n the factory wiring harness diagram for the radio install, by the way.

I'm interested to know where you found the MB-Quart speakers. Are these the drop-ins, or will you have new grills showing?

ew928

In process of replacing CD player in 88 S4.
No amp in this car.
But wiring loom has 2 red wires feeding the head unit.
Thick red is accesory/powered on '+'.
Thin red wire is constant 12V '+'.

How I wish I had a RMB to listen to while
flying around stereoless.
Ernest (NYC)

aircooler

Bob,

These are the best prices I have found:

MB Quart Reference RSC210 $120

MB Quart Discus DSD210 $125

MB Quart Premium PSD210 $250

Cheers,
Mike

natemoran

Thanks for your replies and help - I do have a RMB to listen to so not in a huge hurry to get the speakers working . I tried the red wires behind the head unit; I thought the thin red one was constant but didn't seem to work. I purchased the reference series MB Quarts on ebay (2 sets of 4" RKC 110 for $44 each set and 1 set of component 6.5" for RCE 216 for $152); all were brand new. I plan on running the 6.5" w/o tweeter and surviving w/o an aftermarket amp / sub. I will be installing the speakers this weekend and plan on using the existing grills if possible.

Thanks again.

dr bob

I have already installed Infinity 6.5's in the existing B-pillar housings after doing a little delicate dremel surgery to remove the old speakers. They sound OK, better than what was in there. I'm particularly interested in replacements for the three speakers in each door, with an eye on being able to use the original Porsche grills on them somehow. Mounting depth seems to be the critical factor.

Let us know how your install goes.

MikeN

dr bob

Do you mean two speakers in each door?

I have installed the the MQ Quart 4" midrange driver (RWC100, TX-3) along with the .75 inch 19NX (RTC19) tweeter in the doors with the original grills
without any problems......but a little work. Basically you have to cut the 4" speaker basket out with a Dremel tool, saving the surround, and then sandwich it all together when placing it back in the door. The 4" door opening will only take a 2" depth speaker without cutting metal or a lot more work to make it look stock. Not a problem with MB Quart as most of their 4" separates work fine.

The tweeter comes out of the surrounding mounting rim without a problem. I then fabricated a small sturdy plastic "donut" (painted black) to hold the tweeter in the factory surround. Since the tweeter is so light, I just had to silicone the donut into the surround and let dry.....nice and solid.

I have pictures during the build that I will try and post tomorrow......

Wild Bill

Nate,
Check the 15amp fuse #22 if you do not have 12v at the small red wire of the head unit plug. Also, be sure to check the antenna amplifier connection. Small black wire with separate small connector running to radio plug. It needs the switched 12v source. Mine was disconnected and I had crappy radio reception.

Dr. Bob n Mike,
I to am doing the Quarts up front too. I believe there is only about 1 5/8" of space back there, so I don't know that a spacer will not be required. Hope to use the factory grilles, but not sure if that will work either. I know that this may be blasphemy, but has anyone tried modifying the underlying door panel structure to gain more clearance?

- Bill

MikeN

Behind the 4" door speaker is metal.....and from the looks of it, it is very thick metal or even a double walled area. Anything can be done in the car stereo biz, but do you really want to? The Quarts with some clean power will sound great.

From what I remember there is 1 7/8" of depth, or 2" if you remove the rubber pad behind the speaker. (I'm sure this was to get rid of any vibration issues between the speaker and the door metal). If you stay in this size range you will not need a spacer and can use the stock grills.

Wild Bill

Thanks Mike... good info. You and I were posting at the same time.

Did you install any damping material to the door... Dynamat or what have you? I note that with my 25watt X 4 amp hooked up to the factory speakers the door panels are quite "buzzy" even at relatively low listening levels. Does this go away with the Quarts or did you add damping?

- Bill

MikeN

Nope didn't use anything in the doors, but you certainly could if you want.
Just FYI, dynamat does add a little weight.....don't know if you care or not.
I just made sure that the speaker was not touching anything except at the mounting points. You also want to make sure that there is no path close by for air from the back of the speaker to reach the front of the speaker......cancelling out sound waves. Use a little silicone, insulation, etc. to take care of this. This is usually not a problem in the 928 though.

I would say you will notice a BIG difference between the stock and Quarts.....probably most of the noise will go away as the stock speakers are pretty much crap to begin with.........and now they are 15 year old crap!

I'm only running about the same power you are to the quarts and they are just fine, sound great.

UKKid35

At some point some PO or ICE installer took a tin opener and completely butchered the area behind my door speakers to allow more room for deeper speakers. I should really take a picture and post it as an example of what should never be done - it's almost to painful to see.

zmandan

Hay group.. I' ve been going around and around regarding up grading sound system in my 86.5.

Iam told that the better the speakers the more a amp is needed and that even a high end Alpine head unit needs an amp. Iam also told that componite speaker set up is the way to go???. I do not have a spare
so I could put the amp and other stuff in the spare well.

befor I do any thing I must do some sound proofing ( road nose etc)
or high end sound will be compromised.

Why can'nt I find a Small amp to fit in origional location...run the door 2 speakers with head unit and run rear 2 speakers with small amp.
Am I peeing up a rope with this idea or what?

I just do'nt like idea of losing my spare tire well!

wish I knew more about todays sound system...oh well

dan z

MikeN

My idea of a "great" speaker is one that both sounds great and is efficient
at the same time. MQ Quarts fall in this catagory, as do some other brands.
Some brands sound great, but take a lot more watts to produce the same sound level (inefficient) as a more efficient speaker. So the statement that "better speakers need more power" is not true at all. Sometimes higher end speakers will handle more power, but might not need it.

You may want to add some sound proofing, but most noise in a 928 comes from the tires. So adding some sound absorbing mat in the rear wheel well, behind the big speaker in the back seems to help the most.

I went on a long search a few years ago for some decent, medium power, small amps. Unfortunately today, most prefer a huge amp for the "look" even though there might not be that much guts inside.......looks impressive though.

In the past A/D/S made some great little small amps......some that WOULD
fit where the stock amp went. You can only search on Ebay for them now.
Soundstream made some good small amps that would fit, but again you can only find them used on Ebay today.