Hi, I recently got a Audire Tenendo with the same low gain. I was told that Julius made some of his amps specifically for the film industry and they use a much larger input signal as their reference. I couldn't find a resistive pad on the input really, but did change the 1k and 560 ohm series resistors to 100 ohm ones and I removed the first shunt resistor (before the input capacitor) Don't mess with the second shunt resistor after that input capacitor, I tried a lighter value and the sound was a mess. So then the only thing I could think was to lighten up on the feedback loop as that should raise the gain somewhat. I replaced the 50k series resistor with a 100k and lowered the 560 ohm shunt resistor to 330 ohms. What surprised me was how much better the amp sounds now! Very natural and spacious, yet not too loose (feedback damps the circuit for tighter speaker control) So it seems at least to my ear like this amp had more feedback than was musically needed (critical damping) and so the sound was over damped which shortens the decay of the sound making it sound too tight and dry. I never got up to 'normal' gain, but I sure like the sound more at least! So perhaps he is running the input transistors at a lighter gain place on their operating curve, but I don't know enough to get involved in those changes. So, anyway there is nothing wrong with your amp, it just wasn't meant for home use.
