Hi QRIO
I had both of those amps with 804S and the Source makes a big difference as described above - if you are using a coaxial connection to the 8000AP for music there won't be much gain as the DACs in the AP sound relatively flat compared to higher end Source Players (junk in, junk out) ...the gaps become more apparent the higher up the audio fidelity chain one goes.
>> I noticed more weight and slam in the bass with the 250 modules and better separation of instruments when coupled with Kevin's CD Player (that he lent to me for a while)...the 100X5R runs out of steam at higher volume levels too - the CAPs make a big difference and Kevin has an enhancement for both 100 and 250 modules...quite a few preamp bits he changes which make them sound smoother and more transparent, and with the large Capacitors significantly more 4ohm/2ohm power
Besides, I think your 250 is only just starting to drive in...couldn't have had very many hours on the clock yet!?