If you like the general sound and would like to add bass, try a good power cord on the player. I added two BMI Whale PC's to my system and one of the many benefits was added low frequecncy response (information that I never heard with the other after market cords that I have tried). I use them on the DAC and player and have not tried them on the amp yet.
Where s the bass?
My system - Sony CD player, Pass Labs X0 preamp & X600 amps, Thiel 7.2 and Transparent Reference cables. I believe the sound is open, transparent, and dynamics. However I just wish I could put an emphasis on the bottom end. Tone controls are not available on high quality Class A preamps, such as the X0. While I understand that adding one more component in the signal paths is not desirable as it will further degrade the sound, I would like to hear your opinions on the best way to boost the bottom end. Thank you.