'Ok, anyone got semi decent instructions for this thing?'
I assume 'this thing' is the USBAmp.
'Why does sound come out the front/rear RCA out puts even when the amp is off?'
The amplifier is turned on if 12 V DC supply is connected AND (there is a valid USB connection)
OR (there is 12 V DC connected to the white wire).
With a valid USB connection and sound streaming you get audio to these connectors (line level) because this part of the module is fed from the USB port.
'What would the +12V out of the orange wire be used for?'
You get + 12 V DC on this wire when the amplifier is turned on, you could light a bulb or, you could turn on a subwoofer amplifier or another audio amplifier to get even more audio power if the 4x40 is not enough...
'What is the white "On/Off" wire? I though it was going to be a 12V switched (acc) but the amp powers up even with it disconnected?'
As said earlier, this input can be used to turn the amplifier on when there is no USB connection, the front/rear RCA connectors can then be used as INPUTS for line level sound to drive the amplifier.
'How do the faders work? They don't see to fade anything.'
The faders can be used to increase or decrease the rear volume relative to the front volume, thus balancing the sound level in a car with front and rear speakers.
'To say the documentation is poor is a real understatement. I would probably be better off if it came with none.
To put this into prospective. I am an ex-sound engineer and now a computer systems analyst and I can't figure it out.'
Some people send a mail with similar questions to Xtronic and then get these answers.
Are there reviews available?
Is the device still being produced? If so, how could I get it?
i believe it that xtronic is still selling it, though their site appears to be down right now..
the Xtronic site is up every now and then, seems some hacker(s) keep a close look and tear it apart as soon as it gets up again.
The HQCT and USB amp can still be supplied, send an e-mail to [email protected]. It may take a couple of days before you get an answer but you'l get one.