Aybracers,
Yes, I normally have the gain level set somewhere between -20 to -12dB, so -15dB would be an avarage level.
The "Analogue" pre-amplifier of the CDQ is really a secondary function to its Digital Pre/DAC, the PIP2 - your compairing it with is one of the very best analogue Pre-amplifiers that I've heard - yes, it was VERY expensive for its day!
When your using a high-end turntable system, it would be better to connect the Phono Pre-amplifier DIRECTLY to the power-amps with a passive pre-amplifier - even better then using via the PIP2.
Is there any reason your not using the PIP's internal Phonostage? - you can then connect to the CDQ via the "Tape-out" - connected to the CDQ analogue input. (Its been a long time since I've seen a PIP2, maybe it does not have a tape out?) - Give this a try if you can...
When using the CDQ with Digital sources I recommend using the "Digitial Preamplifier Mode" of the CDQ - this is the simplest most direct path - connecting to the PIP2 will only degrade the SQ of the CDQ.
If your local to the UK, then I can make a Super high performance "Analogue Preamplifier" version of your CDQ, noise levels will take a small hit, but nowhere near the levels of Noise from your phone stage - and with your speakers and listening levels you have indicated, the noise increase will not be audioable...
Also try the Digital filters - for sound stage Optimal Transient wins over the other filters - also insure that you are set for "Digital" Pre-Amplifier (note this only effects Digital sources, Analogue source will always default to Analogue Pre-Amplifier. (Select Pre-Amplifier Mode by "Long press" on the "Mute" button on the Remote Handset).
John