That was a mistake and you hear the difference. The only upgrade that can work for you without "stepping on the toes" of the amplifier's sound quality would be to bypass thoses caps with .05-ufd CRC hermetic teflons that are available through eBay. And let's not forget tubes. Victor Khomenko BAT's designer is limited to what is readily available in terms of tubes. You don't have that limitation. Although there is only one brand of the power triodes, you have the option to experiment with the front-end tubes to dial in your amplifiers. I am a rabid audiophile with a BAT preamp that has those same caps. I can tell you that with those caps still in place and not bypassed, my preamp has yet to get in the way. Tubes on the other hand can make it glorious or crap.
My two cents.
Walt D'Ascenzo
My two cents.
Walt D'Ascenzo