I'm getting my whole stereo system replace. I have a ML system, and I want new speakers in and keep the head unit. How do i bypass that factory amp. The shop I have it at, is having a tough time getting stuff to work without using that factory amp. I have all aftermarket amps, is there anyway not to use the factory amp?

I have a GS350 07 by the way

 

What sorts of things are not working? Let me guess:

No Volume control
No Nav voice prompts
No CD/DVD audio
No ASL (no biggie)

The big problem is that the ML amp receives instructions via a control bus (TX+/- lines) that tell it to set volume and select analog vs digital inputs (among other things). Not sure how to get around that.

Some of the connections going to the ML amp are:

SPD (speed signal) so it can adjust vol/bass with speed. (pin 11)

Navigation voice (pins 22/23)

L/R analog radio audio (pins 2-6)

S/PDIF CD/DVD digital audio

TX +/- digital control bus (pins 7/8)

Mute (pin 1)

You can probably skip the SPD, Mute, and TX lines. Since amplifiers cannot eat digital audio signals, you need to decide if you want to support CD or DVD or both. If neither, then it's easy--ignore the digital audio line. This might be fine if you plan on including the Vasitech iPod adapter, since that uses the analog radio lines. But if you want CD, you need at minimum a 2-ch DAC to output analog, then some sort of switch. Not easy to coordinate the switch.

If you want CD and DVD, then you need a more capable decoder like an Alpine or Eclipse surround decoder. It still needs some clever way to operate the input switch between analog and digital in synch with the head unit. Maybe someone has some good ideas about that.

So here's an alternative idea. Leave the ML amp installed. Disconnect the speakers, run the amp outputs thru LOCs into your new amps.

 

The problem my installer is having is that the factory amp mutes everything if it don't detect the factory speakers.

 

I'm running this with a cleansweep too by the way.

 

That's very strange behavior for an amplifier. If the amp mutes when there's no speaker attached, how does is send a signal to find out the speaker is really there?

So, you are in fact keeping the ML amp in the system after all? Originally you said you were bypassing it.

 

The installer says they need to use the factory amp. and then use the cleansweep to goto the after market amp.

Have you ever installed aftermarket speakers with aftermarket amp into the ML head unit yet?

 

Yes, I agree with the installer that leaving the ML amp in the system will make life a lot easier.

After the CleanSweep flattens out the EQ, what will be used to provide EQ correction for the new speakers? And since CleanSweep cannot handle a separate sub signal, how will that be handled in your system? I assume you will add a new sub amp as well?

I have only added a new subwoofer amplifier https://www.clublexus.com/forums/sho...d.php?t=272881 so I cannot attest to the muting problem they claim, but it sure seems odd to mute an amp when the speakers disconnect. Anyone else run into that? Are they really sure that's what's going on? Does the mute happen for each channel at a time, or only once the last speaker is disconnected?

 

Bump,

Really need help on this guys.

Has anyone installed aftermarket speakers into the GS350 with ML, the amp wont' turn on without it getting signal from the factory speaker.

And we need to use the factory amp so all of the HU function would work.

If anyone have ideals on how to bypass the amp let me know please. But it seems like we need to use the factory amp and make it goto the cleansweep. But amp won't come on unless the factory speaker is plug into it.

 

mefromfl, what ever came out of this?