I implemented additional upgrades to the power supply section of the preamplifier section in my DIY integrated amp:

I added numerous capacitors ranging from 0.1uF to 1000uF to the post-regulator power rail (two TREADs create a +/-10.77V DC power supply) and added 2x 3.32K bleeder resistors.

These are the remaining capacitors in the power supply of the preamplifier section. I had extra bipolar 4.7uF/50V BlackGates lying around, so I stuck those in next to the 470uF Cerafines and the 150uF Panasonic FMs.