Dmak... here is a reply to the email you sent me (my email is down right now)
 

Sorry to take so long to get back to you, email issues. I can recieve them but I can't send them.

For anyone else reading this, Dmak asked me about my old stereo setup which has a bunch of similar components to what he is installing.

Okay, on the amp, hanging upside down from the trunk works perfectly. It has no internal fans or anything but it is very efficient and rarely heats up. I ran the hell out of it for a year including a nasty DC summer (95 degrees) w/out a problem. All you need is four self tapping screws. It is the only nice place to install the amp (since it is so big). It is also easy to run all neccesary RCA and power wires to/from the trunk.

Now, about your power question. You can only run this amp at 50w x 4 @ 4ohms. It would be nice if you could run it at 75w x 4 but that is ONLY in 2ohm mode. 2ohm full-range speakers are rare and there aren't many good ones that aren't major $$$. 50w is a decent amount of power, if you bought Kappa speakers it will be okay as they don't really use THAT much power. I hope you bought 5 1/4" for the front doors as 4" speakers really didn't do it for me. I would go as far as to tell you to send back the 4" and buy some 5 1/4". They fit in very easily with either an MB Quart adapter or your own. The extra midbass you get from a 5 1/4 is WELL worth the extra trouble. I am a midbass nut so I went ahead and but 6.5" speakers up front (uses custom pods... sounds perfect... cost WAY too much!!).

Anyway, if you have anymore specific questions I'm happy to help.

Dan<p>Dan
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Thanks!
 

Dan,

Thanks for the response.. I think I might take your advice and return the 4" for a set of 5.25"..

As far as wiring the amp for 2ohm.. I was thinking of wiring the speakers in parallel to get 75watts per channel.. What do you think of that?

Donny<p><font color="#000081" size="3"></font>
Dmak</font></b>
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Well... not a good idea
 

Wiring in parallel is usually reserved for subwoofers. When you wire in parallel you do split the ohm rating in half (so that is correct), but running in parallel also makes everything run in mono. Running front speakers in mono will make everything sound like crap up front and ruin any possibility of nice imaging. If you want more power out of the 255a, here is what to do.

Bridge the amp to 3 channels which will put it at 150w x 2 @ 4ohms for the front speakers if I remember correctly. This is MORE than enough power for just about any 5.25" speaker. The sub-amp will still do 200 watts which is cool for a 10 inch (although if you get a DVC subwoofer you can run the amp at 300w @ 2 ohms). Now, if you are keeping the stock headunit and rear speakers you can just let the rear speakers run off of the built in OEM amp for rear-fill. I run my car with only front speakers and a subwoofer as it improves forward imaging, but you will still have the flexability to put in some rear fill for people in the back seats.

If you are changing the headunit out, you can just run some new rear speakers off the amplified outputs (unless you got a non-amped headunit... then you just need to decide 150 x 4 or 150 x 2.

HTH,<p>Dan
99 1.8TQMSX K04 Santorin
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