help with stock amplifier plus ipad

[stelan]

Hi I'm installing a tablet to replace the cdr-220 so far I found all the pinout connections that I need but have a question:

The Ipad 3.5mm audio cable has 3 wires (left +) and (right +) and a common ground, the stock nokia 4x40w amplifier has 5 wires to feed audio: (right front +), (right rear +), (left front +), (left rear +) and a bunch of grounds joined into a common ground, do I connect both left + to the 3.5mm audio left and the two right + together to the 3.5mm audio right and the ground to ground or do I only use one of the left and one of the rights and ground, I have been reading and people that tap an aux into the stock systems only connect to 3 wires and not to all 5?

I hope the above makes sense

Thanks for any help

[lkchris]

It doesn't change anything, but the outputs you call rear are actually subwoofer outputs ... for the door speakers ... which are subwoofers.

If you truly had rear speakers, your fader would actually do something. And you'd have speakers in your rear storage box.

There is "rear" wiring from your CDR to the amp, but the 4x40 amp does nothing with it and has no rear outputs.

996 911s come standard with rear area speakers and have 6x40 amps.

[stelan]

so it does not make any difference and I will get the same results. I'm assuming the stock amp filters the outputs so only lows go to the door woofers and mid/highs go to the dash speakers

[lkchris]

That's correct.

[stelan]

Originally Posted by lkchris

That's correct.

Thanks it worked great

[jaykay]

Which model amplifier are you working with? Were you able to discard the head unit altogether?

I would like to do this as well but have 2000 car with the DSP unit with six speakers. I believe it is linked to the amp such that the amp won't work without it present. I belive I need another amp to work with the iPad.

Which amp are you using? What is the nature of your set-up?

[stelan]

Originally Posted by jaykay

Which model amplifier are you working with? Were you able to discard the head unit altogether?

I would like to do this as well but have 2000 car with the DSC unit with six speakers. I believe it is linked to the amp such that the amp won't work without it present. I belive I need another amp to work with the iPad.

Which amp are you using? What is the nature of your set-up?

It is an android tablet 7", I chose that over the ipad even that I had the ipad because the autosleeper app that turns the tablet to standby when ignition is off and because the expandable memory card since I have over 20 gigs of music and my ipad is only 16 gig and because android tablets are cheap as hell.

The amp is the nokia 4x40 stock in my car it is for 4 speakers, the two way on the dash and the two bubs in the doors.

I got rid of the cdr220 unit completely since I dont' listen to radio and much less cd's but android tablets are capable of tuning radio via internet, mine does not.

I dont see a reason why you would not be able to ditch the head unit and cd changer and wire straight to your amp.

[jaykay]

Okay, I am just going by what I have read here. It seems that dynamic sound processing (DSP) equipped cars have amps that are linked to the DSP box in the dash such that the amp is useless without it connected.

I hope that there will be a way to properly test this before cutting. Perhaps if the iPad output runs through the CDR to amp without the DSP box plugged in then I am good to go. I will have to get one of those special iPod cables to test this.

Alternatively, I would have to source a Nokia amp (or after market with six channels) that does not run with the DSP...but I will loose the speakers in the back storage box as it is only four channels.

What model number amp do you have? I am wondering if the harnesses or plugs are different for 4 vs 6 channel cars such that they are interchangeable

[stelan]

The amp connectors are identical, mine is just missing a few wires versus yours.

[jaykay]

.....hmmm so no need to control the amplifier at all?....volume, power?

How do you do this with just the iPad and no head unit ?

[stelan]

Originally Posted by jaykay

.....hmmm so no need to control the amplifier at all?....volume, power?

How do you do this with just the iPad and no head unit ?

The pad has on screen volume and equalizer controls, so no need for head unit. Basically you just need to send music to the amp and a turn-on remote signal to power it on and you control everything else from the pad

[jaykay]

Originally Posted by stelan

The pad has on screen volume and equalizer controls, so no need for head unit. Basically you just need to send music to the amp and a turn-on remote signal to power it on and you control everything else from the pad

Great let us know how it's working. I am surprised no preamp is required. It seems that my amp only works with the DSP so will have to swap it for a different Porsche one.

Did you just splice a head phone jack wire into the harness going to the amp? How did you positively identify it....I guess head unit out and that's it? Did you create a plug on the iPad wire so that you can revert to stock? How are you powering the amp on remotely?

Sorry for all the questions but I no room for a head unit and need to work all of this out prior to getting the use of a workspace!

[stelan]

https://www.google.com.mx/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwj1_-qFlJTKAhWCNz4KHRY5B0gQjRwIBw&url=http%3A%2F%2Fwww.renntech.org%2Fforums%2Ftopic %2F39717-ipod-and-aux-capability-for-becker-cdr-220%2F&psig=AFQjCNEls7kCX1H28_Lr3yjK6cuBqBlJQQ&ust=1452134322755247

It works great, the autosleeper app in the android tab works great, you turn the ignition on and it wakes the pad on and it even continues the song it was playing when I turned it off, sound is great (considering the little power the stock amp has) but again the stock speakers would not be capable of more power anyway. I did replace the crumbling paper cone dash speakers with some better 4" ones and it helped too., the woofers on the doors are doing ok but I have to equalize so there is not excessive base (lows) or it will distort, this is done on the poweramp app that I downloaded that plays music, I still need to learn how to flas the bios in the pad to put a porsche logo on startup but I already have a porsche boxster background image.

I did not kept it as to going back to stock because the previous owner had a mess of wires, I removed an fm modulator, a crappy aux input, he had two amps (stock and another) and wires going to nothing in the back (I'm assuming he had rear speakers at one time.

anyway basically here it is:
look at the back of your stock head unit, it has 3 rows of connectors
you will only need to worry about the yellow connector C1, and two wires going to connector A, all the rest are not used
I used a aux audio cable plugged into the earphone plug in the pad, and cut it, peel the wires and connected one channel together to to the 1 and 4, the other channel to 2 and 5, common to 3 (ground) and power when ignition on to 6 (switched 12v) to turn it on, that's it for interfacing to the stock amp.

in terms of powering the pad used 7 and 8 in wires going to connector A to feed a little 12v to usb adaptor then connected the usb pad cable to that and that's it, you can always get a power wire from the fuse box to feed power to this usb adaptor but I wanted to keep the feature that keeps the power on until you remove the key and or open the door and it works great so if you are at a parking lot waiting for the wife you are listening to tunes with the engine off until you open the door, etc.

Hope this helps

[imari]

Originally Posted by stelan

Thanks it worked great

This sounds interesting...any chance that you could post some pics?