Replacements for C9 and C10 bipolar electrolytics?

[atalio]

I currently don't have a D11, but will be purchasing one. I've looked at the schematic and have a question regarding the output caps.

Are caps C9 and C10 conservatively spec'd in the sense that 100uF will provide a lower cutoff than actually needed? There's nothing wrong with extended response, of course; but I'm wondering if I can get away with a value of around 10uF to 20uF in those positions. My assumption (based on a simplistic analysis) is that 20uF would get us something in the neighborhood of 0.01dB of roll-off at 20Hz. The Jensen, for comparison purposes, is typically down 0.1dB at 20Hz. In any case, if the assumptions are correct, I'd like to swap in some single or paralleled metallized film caps (PPS, polycarb, or PET) in place of the bipolars at C9/C10. I'd probably make this swap for just one channel, and use the transformer in the other.

Bipolars can be quite good distortion-wise (compared to polars), but I'd prefer metallized film if frequency extension isn't compromised to the point of audibility.