Great detail, refinement, mid-price office system?


I am looking to improve resolution, detail, tone in an average sized-office 14 X 14 X 10 feet where only classical, mostly chamber music will be played at low to moderate volumes. Current system is Proac Response 1s, Onix integrated amp OA21s, 50 WPC. Jolida JD100A Stage 1 mod (Underwood) and where restrictions of space for components is 12" depth.
Current system is OK, but would like more detail and transparency, particularly for chamber music and also piano and female vocals.
Suggestions for improvement, please, where budget limit is $2K per component, used.
springbok10
Your system sounds like it should be pretty good as is, but then again, I have not heard the Onix. I really love the sound of ProAc's with ARC gear. In my office system, though, I wanted to go for a more conservative look, and I ended up with a pair of ProAc Tablette Reference 8 Signatures and all-Arcam components (FMJ A22, FMJ CD23T, FMJ T21). I am very happy with the sound of this system. Interconnects are Ridge Street Audio, and speaker cables are bi-wire AudioQuest Gibraltar.
>>09-29-04: Elevick
What tubes are your using?<<

Stock tubes in the Jolida Stage 1 mod (Underwood)
Only Walker SST.
The probable weakest link - because it is the oldest design - is the int amp - 1993. I am tempted by the North Star 192 system however, but would I then have to get a new int amp to optimize the features of the 192 DAC/Transport?
That will exceed budget, though, to replace both.