APL NWO2.5 ?

Alex
I tried to compare NWO-2.5 with or without passing through my pre-amplifier (tubed, famous brand). My pre-amp just restricted performance of NWO on transparency and dynamics. It is very sad that I have to retire my pre-amp from the system.

Audiosu 12-25-06
My sincere suggestion to you: Upgrade to NWO-2.5 first before spending money in amplifier and speakers. Use NWO, which is a recognized SOTA source, as base to see if further upgrading is necessary and appropriate.

Guidocorona
Comparing the sound with or without my pre-amplifier from NWO-2.5, the former is slightly less transparent and has weaker impact. I will not use strong words as "detrimental to overall sound".
The same pre was a perfect match with my CEC TL-0 transport + Audio Synthesis Discrete DAC. I have other system in my Canada home, using the same pre for Oracle transport + Audio Synthesis DAC. They also produce excellent sound for me. In both latter cases, with-pre sounds better than without. (Audio Synthesis has volume control. I let the volume of the pre stay at maximum and addjust the volume on DAC.)
Please allow me not mentioning the brand name of my pre. It is in fact a very good one (so I own two sets). It uses 6350 NOS tubes for gain stage. It probably is just not matching NWO. I will try the OTL mono blocks of the same brand in future.