Bose Stereo Help Needed!

[jond58]

Just trying to work through the final few issues I have with my 2003 turbo. Nearly there now just this hurdle to overcome. It came to me with a Kenwood double din stereo and i believed Bose amp, subwoofer and speakers. So far I've managed to install the stereo correctly as previously it was installed in a cage and an adaptor that looked like it was made by someone who had had the interior of a Porsche 996 described to them over a bad phone line! They certainly hadn't seen or measured up one! So this all works and is tidy and secure but only the dash speakers and sub woofer actually produce sound. No door speakers, no rear speakers. The Bose amp has been removed and an aftermarket amp installed.
So my very basic understanding of this would be that the Bose door speakers are a low ohm speaker with a MOST connection. This amp obviously is wired to the stereo with no MOST and obviously works to the subwoofer and i assume the dash speakers because they're different.
In order to get this sorted am I best replacing the aftermarket amp with a Bose one and getting a plug from a breakers and rewiring what should have been there?? Would it be possible to replace the door and rear speakers with aftermarket ones easily or would i be running new cables? I'm a bit lost with it I'm afraid

 

[911UK]

There are better amps than BOSE on the market

As for the what's in the door, check what type of connections are there but the oem cables are fairly basic

 

[jond58]

So what’s in it is a Powerbass amp. I’ve read a review and they seem decent. It’s five channel. Subwoofer and then front and rear speakers. It’s stable to 2ohms also I checked this. So it has power, the subwoofer is connected and works but no door woofer and no rear speakers. I looked at an American site that suggested wiring the door woofers and sub woofer all as one. It showed how, just had a try of that and effectively wiped out the sub woofer and just had the dash speakers so that was a fail!!! To be honest I’d just be happy if them rear speakers worked. I’m going to cut the install right back and try to reinstall it at the weekend.

 

[jond58]

They seem to have wires for speakers looped together but not connected. I think they may have tried to wire something in series like that but whatever they’ve done it doesn’t work!!

 

[Robbidoo]

I'm a bit confused with what you're saying about the amp wiring but you're on the right path.

The american site you're talking about is probably Rod's CAI store which talks about putting the door woofers and sub in series right? That's actually not a bad option but you will lose a bit of control of the door woofers in terms of frequencies you're sending there.

I have just got finished with a full reinstall where I changed HU, amp, speakers, and only left the sub in (until I can get the time to replace it with a wooden box).

My advice would be to leave the door woofers in and either power them in series as described, or in stereo using the rear channels of the amp, as long as you're able to low-pass them to around 200Hz. Most amps cant' do this and will only offer high-pass on the stereo channels which will give you an issue as those door woofers will only really go up to about 250Hz and you don't want to pull the soundstage into the floor.

I replaced my door woofers with Audison mid-woofers and I wish I hadn't. The Bose woofer really moves a lot of air and there's very little that has that kind of movement in that size that you can use instead. Not to mention you will have to fix the waterproofing on the doors that you will inevitably compromise when doing the swap.

Anyway, I would then wire the dash components straight into channels 1 and 2 of the amp you have. For bonus points and sound replace dash components with literally any 2-way 4" coax. (I actually have a set of Alpines with adaptors for sale that I didn't end up using, PM if interested).

I would not bother wiring up the rear speakers personally.

Please don't consider looking at a Bose replacement amp for it. There was an audio engineer on one of the US forums who couldn't figure out why the Bose never sounded quite right so he put his test equipment in the car and found that the Bose amp has a massive boost at 80Hz no matter what you do with the controls to make it sound "punchy" in the showroom and also give a "kick" when being used in cabriolets. But of course it sounds awful musically and you will never get it to sound "right" no matter what you do.

If I was doing it again I would get a 5 channel amp that will do low-pass on all channels, new dash speakers, wire them to 1+2 with HP 150Hz, wire the door woofers to 3+4 LP 200Hz, and the sub to channel 5.

 

[photek]

To be honest I’d just be happy if them rear speakers worked. I’m going to cut the install right back and try to reinstall it at the weekend.

Sometimes that's the best way to get a clear view of a situation, rather than trying to understand what someone else was trying to do. Good luck!

 

[jond58]

Thanks for the help. So we now have all speakers working!! Firstly I removed the head unit to check the connections. The phono cables were into the rear and sub woofer ports so I move these to the front and rear ports. Made no difference but I think that’s what the manual says the amp should be into. Next I stripped all the speaker wires back and then tested each one individually to identify which wires did which speaker and that the speakers actually worked. Then I wired the rear speakers up into the rear amp connections and the dash speakers to the front connections.
All good, tried to wire the fronts to the subwoofer as per the cai website instructions but wouldn’t work. So I wired the sub and door woofers all together into the subwoofer outlet on the amp. Now all the speakers work!! Hallelujah!! Wrapped the loom in tesa tape and put it all back together. Sure there are better headunits, amps, speakers but I just wanted some working sounds which I now have. Before only the dash speakers worked and the sub box so if you turned it up you could hear the music apart froM the rear window sounded like it would shake out because the only other sound was bass at the back!! Much clearer sound now they’re all working. Cheers again

 

[RobPC]

Glad you got it working. I've been on a journey with mine, I've had to replace the door speakers as one of the Bose originals was blown. I used a pair of Blam 13cms 2 ohm impedance speakers. The Bose boxes needed a bit of fettling to accomodate the speakers but easy stuff to do. I also discovered the source of one of my rattles under the door card so fixed that while I was in there. I replaced the front and rear speakers with Apline 4" units and some 3D printed mounts from eBay which, together with some adapter wires, made it plug and play.

I now have a better stereo with no rattles from the door. However, my Bose sub doesn't work. I suspect the amp is blown so the final stage is to replace it with a 5 channel digital amp and see if I can get everything working, using the original wiring loom where possible.

 

[Robbidoo]

I can't speak to digital (unless you mean class D) - but all of the original wiring should do you fine. Trickiest part is extending it depending on where it routes in your frunk (all cars are a bit different, c2, c4, turbo).