Connecting CD directly to Poweramp

I have an Ah! Tjoeb 99 and recently decided to plug it straight into my (decent) poweramp (audiolab 8000p) and bypass my (mediocre) preamp (NAD 118). This limits me to using the volume control on the CD player. However, the voltage output on the CD is too high for the amp, so I have to turn the volume way down in order to use it. Since it is a digital volume control I am losing a lot of information doing it this way. But the character of the sound is much better, since I am hearing the tube sound of the CD player much more.

I am told that I have two choices (assuming I don't want to spend 2000 bucks on a decent preamp): buy a passive attenuator (e.g. Creek OBH 12) or adjust the voltage output on the CD player (allowing me to set the CD volume at a higher level and so preserve information that currently I am losing).

Can anyone tell me what the pros and cons of these two approaches are? I am worried that using a "passive" unit in the signal path will take away some of that tube sound, but at the same time I don't know what decreasing the voltage output will do, since it is set at the "optimal" level at the factory. On the other hand, with a passive unit I can plug two inputs into it, which gives me more flexibility in the system.

Any ideas, comments?