Hello- I have Reisong A12 and did the mods, with about a 200ohm plate-plate 'Schade' resistors, used 50v nichicon (vs. 35v) caps for EL34 tubes, and used nichicon polyfilm? type coupling caps. Watched video (Steph) about the smoothing/filter capacitors effect on sound etc. So tried swapping in some others and it definately effected sound, namely lost some low-end. Used same original values (33uf-180uf-33uf all 450v). Also tried a 3.9uf 400v Audyn bypass cap on the first 33uf cap after rectifier...didnt sound better, lost bass/lowend. So returned to 33uf Mallory branded cap and the bass came back. There was a noticeable improvement in "stage/separation' or depth with Rubycon caps (I left the larger 180uf in place)...does anyone have recommendation for type of caps/size to use for upgrading the 33uf first and last caps? (Rabbit hole territory :) I know)... but it is kinda fun to swap them and hear diffence in sound. I definately want to 'retain' low-end etc. Using RP-600m speakers. Thanks for any advice, been a fun project to play with...