my PPA v1 (chip-based buffs) in black hammondthis is a work-in-progress but I've got the front panel completed and only the rear panel is TBD (waiting on some parts).
lettering is old school 'datak' rub-on letters. these were left over from about 20 yrs ago and I'm surprised they even still work.
plastic panel is some thin cut-to-size stock at my local plastic (TAP plastic) store. its easy to work, it shows NO fingerprints (lol) and its forgiving if you slip up. not really strong but its strong enough for a poor man's 'FPE' sort of
neutrik all-black socket from parts express. I went out of my way to find a black/black neutrik and PE had it all along
the PPAv1 normally has no bass 'control' but it was easy to add. you can see the wima's sitting directly on the bass control (rear view).
for the phones-out, I snaked the 3 needed wires from *under* the board thru a drilled rubber grommet up front. its a bit neater that way, I think.
I used machined pin ic sockets to make a quick-release interface for all the front panel controls. now I can unhook the front panel for service and that was worth the extra effort (soldering, heat-shrink tubing and all that). some more still has to be done before I'm really finished, and then the whole socket bundle (per group) has to be tape insulated or something, for when you stuff the wires inside the box.
there are 4 buffers per channel (fully maxed). these are the buffers you CAN buy (ahem! cough.) but they still aren't cheap (about $5 each chip).
the op-amps are very old samples (again, maybe 10 yrs old) of BB opa627 chips with the center being an ad8610 on a browndog adapter.
resistors are vishay. caps are generally whatever I find at my local surplus shop
update: added a bantam dac 'plugin' for fun