Serdar U

Disclaimers: If high wattage and booming bass are highly desired, this solution is not for you. You'll still need a dedicated power line to a high-power amp. As always, what worked for me may not work in your case, so follow these comments at your own risk.<p>Like many other readers of this forum, I've been quite disappointed with the sound quality of the Concert (stock) speakers. I've been reading about various installation methods for a rear amp, and all reports I've read so far required a power line direct from the battery to the amplifier. I do not need hundreds of watts of power to satisfy my listening needs -- I listen to music at relatively tame levels. Anyway, I finally took the plunge and replaced my front + rear speakers and added a 2x30W amplifier below the rear deck. I was able to do this without drilling a single hole in the car or destroying any of the stock wiring harnesses. I also managed to power my amp without laying a direct line from the battery through the firewall to the amp.<p>Rear speakers and amp: I replaced the rear speakers with MB Quart 6 1/2" Autobahn coaxials (Quart Mobil 1216 KX). I used the MB Quart Audi A4 rear deck speaker adapters for a direct fit. I installed an Alpine Flex2 MRP-T306 amp (2x30W RMS @ 14.4V; 2x60W max) under the rear deck using steel brackets. <p>Rear wiring: The harness that is connected to the left rear (active) speaker has eight wires. RR+ (preamp), RL+ (preamp), RR/RL common ground, RR+ (to speaker), RR- (to speaker), control (white wire), unswitched 12V, and power ground. The unswitched 12V power is connected to fuse #37 (20A) through a 16 gauge wire. Other devices on the fuse 37 circuit are the Concert head unit (5A fuse), CD changer, and cellular phone. I figured I can safely use 5 amps on this circuit for the Alpine amplifier. <p>I removed the connector from the active (left) speaker, threw the speaker away, and soldered all wires to the salvaged connector. That way, I did not have to cut the wires coming into the factory harness (for whatever it's worth). I connected the amp to the 12V unswitched power line (red/blue stripe). For added protection, I limited current on this circuit using a 5A inline fuse. I used the active speaker power ground (brown wire) for amp power ground. I used the white wire to turn the amplifier on and off. I wrapped all wiring in neopyrene rubber and tucked them neatly into a groove at the forward edge of the rear deck. I'm pleased to say that the system sounds great and there is no static possibly because the speakers and the amp are grounded using the grounding points on the factory harness.<p>Front speakers: I used MB Quart Autobahn 5 1/4" component speakers (Quart Mobil 2213 CX) + MB Quart A4 front door adapters. I used the instructions provided by Dan Masi in the FAQ. I must admit that the front door installation was pretty tough (there are ten electrical connections + one mechanical connection that you need to remove in order to remove the driver's side door panel!) but it all worked fine in the end (about two hours per door). Two interesting points: 1) It's not obvious from reading the FAQ, but the front door speakers are mounted on the removable door panel and not the steel frame of the door; 2) In Dan's car the driver's side midrange speaker had a second voice coil for the phone. My car did not (98.5 1.8T). In my car, I presume the phone circuit is mixed in with the other audio circuits inside the Concert radio. The end result is that I should still have the hands-free phone capability even though I replaced the stock speakers. Cool!<p>All and all, I ended up with a pretty decent-sounding setup with nice, tight bass, realistic midrange, and crisp highs. Total cost of the system was around $950 ($300 CD changer, $130 amp, $350 speakers, $80 speaker adapters, + misc. hardware + tax), and I'm still glad I didn't spend my money on the Bose system.<p>I can provide wiring details if anyone is interested. Thanks to Steve Shupe of Carlsen Audi for photocopies of the Concert wiring diagrams and Dan Masi for the excellent FAQ entry.<p>Serdar Uckun<br>98.5 1.8T QMS (brilliant black, terra cotta)<p>Email: uckun "at" hotmail.com (still trying to keep my e-mail address safe from spammers)

SandyK

I'm almost done with my install. I was wondering, can you give me a description of the rear MB Quart adapter? I'm curious as to how the adapter is bolted on (what is the hole pattern?). I'll be done with my install but I haven't replaced the rear door speaker yet. I'm thinking the rear deck adapter might be useful to me. Thanks.

David White

This is not a flame by any means, I am just trying to help!!<p>The alpine amp that you are using, will require more current than the old amp….the MRP-T306 has a 15 amp fuse and alpine recommends using a 20 amp inline fuse near the battery. The power wire that you are using is probably 14 or 16 gauge, and wire that small should not be used to draw 15 amps….i would suggest using either 8 or 10 gauge power wire ran to the battery with a 20 amp inline fuse no more than 18 inches from the battery…<p>In general, you should always power an aftermarket amp (however big or small) directly from the battery with an inline fuse as close to the battery as possible!!<p>It is not too difficult to run a small power cable to from the battery to the trunk…I ran a fairly large wire (4 gauge) from the battery to the trunk with no cutting….<p>You are asking a lot out of that fuse (37) by adding an amp that is fused at 15 amps to the circuit…whether or not you ever crank that amp up, it will definitely require more than the 5 amps that you have allowed for it….<p>Also, drawing a lot of current through small wires can be very dangerous (the wire could get very hot, melt the insulation, cause a short/smoke/fire,…you get the picture)!!<p>Just my $0.02<p>David White<br>98 2.8qm<br>

Serdar U

David,<p>Thanks for your comments. You are correct in stating that the Alpine amp is fused at 15 amps. However, I *do* have a 5 amp fast-blow fuse in series with the Alpine amp. Therefore, it is guaranteed to never draw anything more than 5 amps (OK, perhaps 6 or 7 amps momentarily before the lower-rated fuse blows ...). <p>Another current limiting factor is that the gain (input voltage level) on the Alpine amp is turned way down to accommodate the high voltage levels coming out of the head unit. All and all, I surmise that the amp generates around 5 Watts per channel during normal listening levels, perhaps peaking to 15 wpc. Let's assume 50% wastage in the amp, which gives me a budget of 45 watts to handle the peaks. At 12 volts, that's less than 4 amps during the peaks and 1-2 amps during normal listening. At 14V (which is the typical reading on my dash), it's more like 3 amps. I figure the 14- or 16-gauge wiring (which is also used for the Concert head unit with a 5A fuse) should be able to handle that.<p>In any case, I'll monitor the wiring for heating over the next several months, and I guess I can always go to plan B if I smell anything funny :-)<p>-- serdar<p><br>

Serdar U

Sandy,<p>If I remember correctly, the rear adapters have three mounting holes positioned at 90 degree intervals (front, rear, outside edge). See below.<p>NOTE: Regardless of what the MB Quart web site says, the adapters are for 6 1/2" speakers, not 5 1/4". I learned this fact the hard way -- I had to send my 5 1/4" speakers back after I saw the adapters. You may be able to get 5 1/4" speakers to float over the hole using brackets or something, but 6 1/2" is the direct fit. For a rear door application, why don't you consider the front door adapters instead?<br><ul><li><a href="http://www.mbquart.com/mobil/adapters.htm">MB Quart adapters web page</a></li></ul>

Rich Quinlan

I have seen tests before conducted by Buss Fuses, and a, let's say 10A fuse, took over 20amps before it blew...and that was for a few seconds.<p>I do admire your idea, and the execution sounds good. HOWEVER, if you REALLY REALLY don't want to go into your engine comp't, try this: Pull the knee panel on the driver's side.. look underneath, and you will see a row of bolts with wires coming off them. All the way on the left, you will see a large (about 6 gauge) red wire terminating to a stud. This (verify with a multimeter) is constant 12v+, straight from the battery. You can simply undo the nut, and slip a ring terminal onto this for constant power. I only recommend this for low-wattage amps like yours.<p>Good luck and happy ears!<p>Rich Quinlan<br>'97 1.8tqms with 650 (RMS) watts of soundstream power! "Huh? say again?"<ul><li><a href="http://home.att.net/~richquinlan">Quinland</a></li></ul>

SandyK

The rear doors are 6 1/2" diameter. But the mounting points are kind of odd so I would have to build a custom adapter for them. I was hoping that the rear deck would be similar enough that I can modify them to fit into the rear door but it doesn't appear to be.<p>BTW, how many companies were involved in making the OEM speaker combo? I had counted three different manufacturers. Blaupunkt made the front tweeters (cheap foam). Nokia made the front mids (paper cone). Isophon made the rear door speakers (paper cones). I didn't take off the rear tweeters to see who made them (they're mounted coincidently).

Serdar U

You're right -- three different manufacturers. The right rear deck speaker that I pulled out of my car was an Isophon made in Tunisia, and the left one was a Nokia (probably made in Finland, but I'm not sure). The front midrange speakers were Nokias (same manufacturer on both doors -- what a concept!). Front tweeters were also made by Blaupunkt and I can't recall where they were manufactured.