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Problem with Alpine ILX700

uk996

Well-known member
Joined
9 Jan 2018
Messages
282
I had PCM and Bose, non MOST system, it sounds rubbish, one note bass and overall poor SQ.

I got the PCM swapped out with the ILX700, mainly for Apple play and hands free, I asked a garage to do it. It sort of works, but sounds terrible. I get a horrible hiss too. The gain setting aren't right, volume set to 2 is just about ok, 4 it starts to distort. I guess I need to turn the gain down somehow, either on the amp or the headunit.

I've checked the headunit and used Alpine tuneit, but nothing. I'm wondering if the person that installed it wired up the speaker out to line level.

Any one got any ideas? (I've started a new thread as the old one got spammed) thanks.
 
Hiss could be due to gain too high on amp, but also a fault with the amp.

My passenger dash speaker hisses slightly, never noticed when I had pcm installed/thought it was sound of cd spinning up. Functions perfectly otherwise. I checked that it was most adapter etc

One of these days I'll get round to taking it apart and rectifying it, for now I'd forgotten about it until o read your post.

Wonder if there's a way of doing a master reset on the amp to put it back to neutral values without having to resort to reconnecting pcm? (bit of faff and risk damaging dash etc in the process)

Dan
 
Hertsdriver - thanks for that. I'll have to reinstalled the original PCM in that case. I presume if I replace the BOSE amp, I won't have to do this? Plus it should be better.
 
uk996 said:
Hertsdriver - thanks for that. I'll have to reinstalled the original PCM in that case. I presume if I replace the BOSE amp, I won't have to do this? Plus it should be better.

If you have access tot he PCM then it isnt a big hassle to plug it back in and set it all to zero.
The other thing I thougth about was have you set all the ILX's various setting up correctly? I took all the artificial booster type ones off of mine when I fitted it, and remember theres a setting for carplay, aux, radio....

in regards to BOSE 'better' is a subjective term.... :lol: from memory there are 3 or 4 amps in the BOSe system, so its a lot of work to remove it all. Do you know what MOST convertor was used in the install?
 
Mine isn't MOST, no fibre optics in mine

I meant anything else I replace the BOSE with would be an improvement
 
interesting, door speakers have BOSE emblazoned on the front. I didn't get the MOST adaptor, but I didn't install it.

Looks like I need to take it out to reset the amp settings and then I can check to see if it's been connected to the speaker out.
 
I've also swapped out my PCM with an aftermarket stereo and also get an irritating hiss and despite paying for a harness, it doesn't sound like the amp is connected.

I need to take it back to the installer, but initial research has suggested that the hiss might be to do with the earthing cable
 
Ok, I've got round to plugging the original PCM2 back in. Checked the audio settings and they were set to flat :-(


I bought the connection kit from Autoleads, I was recommended their Audi Bose harness which comes with the Autoleads H2L, a high level to low level converter.

Bear with me here, this gets complicated.
1) I disconnected the audio leads (phono) from H2L, music kept playing. I followed the cable to the connector which connects to the car's harness. There is nothing there on the car side.
2) the balance and fader controls don't make any difference via the amplifier, I've checked the HU via the line out, it all works from there and sounds quite good.
3) The active aerial converter has a blue lead, which wasn't connected to anything.

I've come to the conclusion I've been sold the wrong harness and the person who fitted it doesn't have a 100% grasp of how it works. I've connected the blue cable to the power antenna lead on the HU, not suprisingly, the radio reception is much better now.

My PCM2 & Bose system definitely doesn't have the MOST system.

Next steps is to contact Autoleads and see what can be done. Hopefully I can move a few of the pins and wire it up from the pre-out, low-level output and regain balance, fader and improve the sounds quality.



 
Yes, I'm fairly sure the MOST system came in with the facelift model and isn't Bose specific.
 
well thats weird, as the OP's car is a facelift (at least it has a glovebox from what I can see).

I guess the fact that you have disconnected something and can still hear something sort of points to some of the bose amps not working, and that would certainly explain the poor sound.

when you reconnected the PCM did it all sound ok?
 
All 996 turbos came with facelift lights. Mine is 2002 MY and has the glovebox, but not the MOST system.

Hmm, the sound quality is poor with the OE PCM2, but worse with the new HU. I've got a hunch and I'm going to test it again.
 

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