I've been checking these boards for more info on monsoon also. I posted the following in another thread but it seems appropriate.....
Originally Posted by NeckPayneIn case anyone still surfs to this thread, since I got confused myself.... It seems R32 Juhl figured out an answer on this. For those of us who have just enough money (and spousal support) to devote to the "carputer" and not upgrading the system with new headunits, amps, or speakers, this option needs to elaborated on.
Check out his install thread:
2004 VW R32 Install - NOT DIAL-UP FRIENDLY
Post #81 was the "Eureka"
Seems as though the HU supplies a 5v current (yes, I know voltage is differential and amperage is current) through the left speaker which acts as a turn on lead to the monsoon amp. So its possible to ditch the HU and wire straight to the monsoon amp from the soundcard. I'm not quite sure if from what I read from Juhl's post if this is the same as BTL (bridge-tied load) in which instead of a speaker signal comparing a positive voltage to ground, the voltage is balanced between the two leads. So if a 12 volt signal is used, bridge tied loads send +6V to one channel and -6V to the other. In this way, less voltage can be used to effect greater amplification.
What I'm not sure is if what Juhl's suggesting is by throwing this 5v onto the left common, if we are "creating" the BTL and balancing this against the speaker output from the soundcard. In essence, the BTL input is what triggers the amp to "turn on."
Some people have mentioned that the monsoon amp requires speaker level input. Is this because they were unsure of this BTL requirement, or is it that speaker level output is BTL and so that's why we're able to get it to work now. And then, does Juhl's solution work because we're "fooling" the amp.
Either way, I still don't understand how exactly to set this up. Also, there is some issue regarding a difference between the 2001 monsoon and the 2000 and >2001.5 monsoon system wirings. I have the single DIN monsoon from 2001, does this make it the 2001 instead of the 2001.5 or is that not the deciding factor.
Thanks for anyone's help!!