Tom Feldmann

Hey all,
After spending a few days with my new-to-me whip it has come to my attention that the factory stereo in the .1 is just kinda..well..dated. I'm looking to throw a Pioneer AVIC X200-NEX in. I'm not sure of which version yet but they all have the same pre-amp so it shouldn't matter for this discussion.

My question is...can I wire up the speakers directly to the head unit or do I need an amp? I've read a few articles on the p.i.t.a. it is to update the bose system but all of them indicate the necessity to either go nav-tv or replace the amp.

My intuition says its possible to wire directly to the head unit but I'd get better sound if I replace the amp. Thoughts?

-T

rickster997

I just installed a 4200 nex in mine. I opted to go with http://www.ebay.com/itm/222186255168?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AITso I could use Bose and speakers. Sounds great, plus I can always reinstall the original radio if I want to sell it.

user 72902

I have an AVEX and had it professionally installed and I'm pretty sure I didn't buy an amp. BTW you will loooooove it so much more than what you had.

JCGMS

I went the MOST-HUR route also, which allows you to swap in an aftermarket receiver and keep the Bose amp. Very DIYable, especially if you've ever swapped out a car stereo before. Instructions for removal are all over the forum. Loi at euromotorspeed (eBay) sells a kit with everything you need, including a color matched faceplate, and has superb customer service (no affiliation, just a very satisfied customer).

Also, you may want to check out Ryem3's "budget audio install" thread in 6speed. He details how to swap out the crummy Bose speakers, with reportedly great effect. This may be my next project.

Bruce In Philly

I will provide a bit of information, but you will have to confirm all of this by doing a bit more research.

Do you have the premium sound package? On the PCM3 in the 997.2 it matters. If you have premium, then the head unit is connected to the amp via a fiber optic cable and you can't use the existing amp. If you don't have the premium sound, then the analog pins on the back of your head unit are active and connected to the amp via analog cables, therefore you can use the amp.

If you don't use the amp, you will have run speaker cables from where they are terminated at the amp, back to your new head unit.... or conversely, run analog lines from your new head unit to the old amp.... depending.

IMO, I highly recommend replacing the amp with another... don't cheap out and just do it right. If you have the premium sound, you most likely will need the extra juice of a separate amp to drive all of the speakers and to give you the balancing/cross over etc control to tune the system.

There is more over at 6 speed.

Good luck..... oh, and in your research, you will find a few audio installers post. They are all cooperative and will answer your questions via email even if you don't live near them.

Peace
Bruce in Philly

Bruce In Philly

I did just this, replaced my speakers with the Focal solution.... and I posted my results deep in that thread. In short, it is not really worth it. It is a ton of effort, you will need to Dremel the crap out of stuff, buy and or make some mounts, and put in many hours. The result? Meh.... The sound was improved but not by much. If you already replaced the electronics, you may get better results as the Bose amp is not that great and hard sounding.

I had the fortune to hear a side-by-side with my car where the other car just swapped the electronics and kept the stock speaker setup.... way way nicer than mine. The devil is in the electronics and not the speakers.

Peace
Bruce in Philly

semicycler

The subwoofer has a second dedicated amp inside so it can be driven directly from the Pioneer preamp outputs. But there are four pairs of other speakers, too many to drive directly from the Pioneer unit (dash tweeters, door mid range, door woofer, rears - I'm ignoring the dash center channel as that's not used in most aftermarket head units). So it really helps to have a separate amp, or at least one to drive half the system. The only real decision is to whether to keep the Bose amp or replace it, not eliminate it. For example, the dash tweeters are wired in parallel with the door mid ranges. The door woofers are mono with the Bose amp as best as I can tell, but they are wired in stereo. And then there are the rears. This is too many speakers or at least too many separate channels to drive directly from a Pioneer head unit.

The MOST/HUR device allows you to swap just the head unit keeping everything else as-is for the speakers and amp. The wiring is simpler especially in a 997.1 since the amp is in the frunk and running wires through the firewall is not fun. And going back to stock before selling the car is super easy. But there are some limitations - the Bose amp with the MOST/HUR has no dynamic fader control, you must set it up with the existing Porsche radio then it stays that way with the new radio making it a static fader system. As a matter of fact only the front left/right preamps are used with the MOST/HUR device. It sounds great once setup but it was surprising to find out after the fact that fader is static not dynamic. But you do have dynamic balance control. And there is a simple wiring change to separate the subwoofers and drive them directly from the Pioneer unit.

If you do use a separate amplifier there are more wires to run, especially if you want to separate the dash tweeters from the door midranges. But you will end up with full sound control. Typically the dash tweeters and door midranges are left in parallel and driven by one pair of amp channels. The door woofers are driven by another pair of amp channels. The subwoofer is either driven by a preamp out of the head unit in a 4 channel amp system, keeping the internal subwoofer amp, or driven by the amp's sub out in a 5 channel amp system and bypassing the internal subwoofer amp. The rears then either need a second two channel amp or are driven directly by the head unit's powered outputs. It sounds great but going back to stock is really painful.

So which is better? Depends really on what you want to accomplish. The head unit alone gives the most sound improvements. New amps give better control and some incremental sound improvement. But with so much road noise in these cars that simply going to a better head unit is more than enough. Plus if you go with a new amp you might as well go the full route and replace the Bose speakers to truly make the sound better. It's a slippery cost slope. If you want to keep costs down, make installation easier (easier, not easy), or plan to go back to stock then the MOST/HUR is the path. Just be aware of the static fader control and setup your sound stage before removing the Porsche head unit.

Tom Feldmann

Thanks @semicycler, good information there...pretty much exactly what I was looking for!

Thanks for the input everyone!