Upgrade the upgraded sound package on the Boxster 987

[erickasper]

Well, I decided to upgrade the "upgraded" (with the ASK amp) sound package in my 2005 Boxster with JL amplifier (it has high level inputs), rear speakers and a subwoofer.

I have run in to a problem that I can't solve. I have a hum at all the speakers. It is there even if the radio is off, but the amp is on. It goes away if I disconnect the high level inputs, so I don't think it is a grounding issue. If I turn up the input sensitiviy, the hum gets louder so I am suspecting that the CDR24 has something strange with its output.

I have run the outputs to the high level inputs on the amp and, of course, disconnected the ASK amp, and extended the speaker wires from the ASK amp and the HU and connected them to the new amp. If I jumper those wires together, in essence reconnecting the CDR24 to the speakers without the ASK amp, there is no hum.

I am going to connect a source to the low level inputs to check it out from that end.

Any other suggestions would be appreciated.

Thanks!

[grahamwhite]

Well, I decided to upgrade the "upgraded" (with the ASK amp) sound package in my 2005 Boxster with JL amplifier (it has high level inputs), rear speakers and a subwoofer.

I have run in to a problem that I can't solve. I have a hum at all the speakers. It is there even if the radio is off, but the amp is on. It goes away if I disconnect the high level inputs, so I don't think it is a grounding issue. If I turn up the input sensitiviy, the hum gets louder so I am suspecting that the CDR24 has something strange with its output.

I have run the outputs to the high level inputs on the amp and, of course, disconnected the ASK amp, and extended the speaker wires from the ASK amp and the HU and connected them to the new amp. If I jumper those wires together, in essence reconnecting the CDR24 to the speakers without the ASK amp, there is no hum.

I am going to connect a source to the low level inputs to check it out from that end.

Any other suggestions would be appreciated.

Thanks!

You could be wrong, it could be a grounding problem, if you have tried all the usual tricks like running fresh cables and plugging other sources into those inputs (such as ipod or other portable mp3 player) if none of these things have worked it could be a ground hum present within the CDR which is being gained up at the next stage, therefore introducing a loud hum out outputs.

If you plug in the fresh source (the ipod) directly and do not get the hum, you will at least know that the fault lies not with your installation but with the existing hardware. You can buy ISO boxes which sit passively inline and cancel out many grounding hums and buzzes. this could be something to look for if all else fails.

Graham

[rye595]

Curious to know if you ever got this sorted out. Also, when you disconnected the ASK amp, didn't PCM throw some sort of error code saying there's no amp connected? I heard this could be a problem. I'd like to do something similar.

Thanks!