Inside view: Audiolab Q DAC
The OPAMPS are OPA134
There is no short circuit protection for the outputs which is a bit of a glaring omission.
The relays mute the outputs at switch on, and when headphones are plugged in, however they do not provide protection for the output stages!
It looks as though the output stages run in class a going by the amount of heat generated.
I really would like to get a schematic for this, but so far all I've been able to find is a schematic for the 'M' DAC.