What should I upgrade first amp or preamp?


I need your help. I have OPPO BDP-105 connected to PASS Labs XP-10 and XA-30.5 driving 89 dB at 4 Ohm Snell C7. Looking to upgrade my system and planning to spend $ 3000-4000. I live in the apartment building and unfortunately can't listen to music very loud (no more than 58-62 on the XP-10 display).
What would you suggest to do, upgrade preamp to XP-20 first or amp to two XA-60.5 or to XA-100.5 and why. Upgrading an amp is more problematic due to the space constrains.
What will I gain and what should be the difference in sound in each of those cases?
Thank you.
karapuz
I have an Ayre C5 and it is excellent, however, I think the amp and pre should be bought together. If your budget doesn't permit that now, I would listen to earphones until the budget works.
While the XA30.5 probably has all the power you need, my Pass dealer had told me that in the XA series, more so than the X series, the overall sound quality improves more each step up the line.
on the other hand, the move from the XP10 to the superb XP20 is both a significant step up and much less costly than moving up the amp line...
While the XA30.5 probably has all the power you need, my Pass dealer had told me that in the XA series, more so than the X series, the overall sound quality improves more each step up the line.
I would speculate that a major reason for that would be that the higher powered XA amps continue to operate class A up to considerably higher power levels than the XA30.5. But considering the OP's listening levels and speaker sensitivity, it seems likely that his XA30.5 goes into AB mode rarely if ever.

Regards,
-- Al
Not to mention that even though he mentions the XA100.5, he would have to double the amount he states he wants to spend.