M490 + Rear Bose Help Needed

[subwiz]

Hi,

I am the new owner of a 2004 Boxster S with the M490 Hi-FI Audio system, which does not have the rear speakers. I really want to keep the OEM look to the cabin so I purchased a BOSE rear sub speaker.

I just found out that the BOSE has a really low Ohm rating, so I am not sure if it is a good idea to connect this directly to the unused two rear channels on the M490 system.

Could someone help me out with the how to connect the BOSE to the M490?

Thanks,

David.

[Cloudsurfer]

Probably not the best idea I'd have to guess. If you REALLY want to run that, I'd get a dedicated amp to power it, or simply install a sub the right way (i.e. not two paper cone 5" drivers that Bose calls a "subwoofer").

Patrick

[subwiz]

Hi Patrick,

Thanks for the reply. The main reason I opted for the BOSE was I wanted to keep the factory look.

My local install shop sells JL amps, would that be OK from what I have rean the low Ohm rating of BOSE equipment would fry it over time, am I best looking for a BOSE amp that was made for this system?

Thanks,

David.

[ChrisZang]

Hi,

I installed a BOSE rear speaker system to a non-Bose amp and put a lot of my findings here: Bose Upgrade of Speakers ..etc
please read the whole thread.

first of all: do not connect the speakers without modification to your amp, you will most likely blow the amp.

Long story short:
The Bose rear speakers a wired very weird:
You would expect that you have a pair of speakers for the left and a pair for the right - wrong.
The two tweeters are wired together and the two subs a wired together.
So de facto the left channel drives the tweeters and the right channel the woofers - as I said weird.

So the first thing you need to do is to open the BOSE speaker encasement and re-wire the speakers and put a woofer and a tweeter in-line so now you end up at least with 3 Ohms on each channel - but it will sound like crap as the impedance of the speakers does not match your amp.

I ended up replacing all speakers in the Bose box with aftermarket speakers and a crossover.

I am a bit in a hurry at the moment, if you are interested I can put a more detailed description together later (maybe on the weekend), let me know.

[Cloudsurfer]

The long and short of it is that Bose equipment is junk. While I can see the merits of keeping the Bose enclosure to keep a stock looking install, but at least replace the guts with decent components. If you do choose to run the Bose as-is, take the hint and do rewire it.

As for amps, any good amp should be 2 ohm, if not 1 ohm stable (the JLs "slash" series are 1 ohm stable). 3 ohms is nothing to do a good car amp.

At the end of the day, I would just install good components and enjoy good sound.


Patrick

[subwiz]

Hi Patrick, thanks for the candid reply. Based on what I have read, I am a little unsure if I even want to go ahead with the install of the BOSE.

I will try and find a local car for sale and take a listen to get a better idea if it is worth the expense of installing, or just resell it and go with Dynaudio's up front and forget about the rear.

ChrisZang, if you can put some more info together that would be great too.

Thanks,

David.

[subwiz]

In my quest I fell upon this link to some new JL slimline subs

http://mobile.jlaudio.com/jlaudio_pages.php?page_id=213

I am not sure if this would fit in the passenger footwell, could someone take a look at their tech specs and let me know if this might be something worth waiting for as they don't release this range of subs until late 2007.

Thanks,

David.

[subwiz]

Think I am going to take Patricks advice and not install the BOSE, will relist it back online for sale and look at upgrading the front speakers only.

Thanks for the advice.

David.