Floodj

My old amp died, so it was time for an upgrade. I replaced an old Sound Stream with a JL 4x100. So far I really enjoy it. The amp sounds clean, I have Focal speakers which like the power. I also changed the way the amp is mounted. The old one was just screwed to the floor in the trunk. It took up a ton of room, and looked bad. I had them put the new one where the CD changer used to be. I really like the new location, the new look, and especially the new sound.

Spyder_Man

Interesting suggestion on amp location. I have some three way speakers that are going to require bi-wiring so if I want my rear speakers amplified properly I might need a second amp. One under the passenger's seat and one in the frunk I suppose.

Kika

Here's another mounting spot.

rlme36

I mounted mine under the passenger seat, Hertz 4 channel amp easy fit no clearance issues.

x50type

Better under the passenger seat.

WTH have you in the frunk pocket - it looks bloody nasty.

Spyder_Man

Under the seat is still ideal based upon how the speaker wiring is set-up. The challenge is I will need four channels of an amp dedicated to the door speakers. Possibly two more for rear speakers. Possibly one or two more for sub, if I go that route. There aren't single amps that can do all of that and fit under a seat in a 993.

I'm still going back and forth about using the existing wiring or new speaker wires. I'm sure new will sound way better but would be a huge PITA to install. I don't want to damage the factory wiring loom either.

Decisions, decisions...

rlme36

So the question I have for you is, is audio really that important. a good x-over for front separates and rear as fill is plenty in the car. YMMV. My second point is, Have you looked at Fister cans? I did the stereo install and now its just a noise spacer until I can use the go pedal to hear the exhaust note. Just sayin.

Spyder_Man

I am set on the door speakers, which will require the 4 channels even with a x-over. I'm debating (A) replacing the rear speakers with new OEM (one is already non-functional) and powering them with the receiver directly or (B) replacing them with good aftermarket rear speakers and powering them with an amp. New OEM speakers carry the OEM price premium and are rather crappy compared to modern speaker materials. I suppose there is option (C) replacing the rear speakers with low-power aftermarket speakers and powering them with the receiver.

Fister IIIs are on the to-do list so I agree fighting the bass notes form the exhaust and go pedal with the bass of sub-woofers is a silly prospect.

Anyone have measurements for what the maximum allowable amp dimensions are for fitment under the seat? I know my OEM amp is about 7.5" x 7.5" x 2". I've read about people fit amps closer to 11" x 8.5" x 2". Would an amp 13" long be too long to fit?

rlme36

I don't recall the dimensions of the hertz amp I am sure it's out there though. Hdp4 I think was the model #

x50type

There are reams of info on what you are attempting -- try search.

they range from inexpensive to if you have to ask!

Spyder_Man

I've been reading up on all the old threads about stereo replacements. People have fitted a variety of amplifiers under the seats, but I have yet to see definitive maximum fit measurements posted in a thread.

The Hertz HDP4 is 11.18" x 6.73" x 1.83". I'm eyeing a new Focal D-class amp that has the measurements 13-7/8" x 8-7/16" x 2" and wondering if it will work.

Kika

you CAN run the doors off of TWO channels. If you are running the crossover before the amp and using dedicated channels for each frequency band, then you are building more than a conventional system and will need lots of room for amps. If you are going down that path, you may want to also think about a secondary battery as well.

There are lots of ways to build a system, for mobile applications a simple way to go is a 2 channel amp for the front speakers, and headunit power for the rears. In my 911SC, I used a 4 channel amp, but bridged 2 channels to power a subwoofer in mono, and used the other 2 channels to power Boston Acoustics Pro speakers, and headunit power for the rear fill.

space under the seats will also depend on which seats you have, and assuming they are adjustable, how they are adjusted.

rlme36

Buy the amp you want and see if it fits. If not return it. Easy peezy

x50type

Did you check out pilotjosh post of 06/05/2015 -very neat set up with rockford fosgate under px seat.

Do you want the dimensions of the OE Nokia amp?

Spyder_Man

Thanks all for the tips. The OEM amp in my 993 is about 7.5"x7.5"x2". I've got that measurement known. I might just have to get out a tape measure and start poking around under the seat.

I'm not aiming for a bi-amp setup, but I've read that these speakers maybe require a separate channel to the woofer to work properly. The speakers are Focal KRX3. I'll be posting a detailed write-up once I figure it all out.