@immatthewj to answer your questions, after I recapped with those specific caps, and tried different designs of silver-over copper and more pure copper interconnects between source/preamp, preamp/amp, in my case, and for my particular speakers it was a dead-on match for my taste and ears. Not to over think this too much - I simply enjoyed those particular EL34s at the time. I figured out who was making them for Ruby lable brand [at that time] and the sound is where I wanted it to be, for me. So, I did not change to different tubes, although I came close to trying the reissue Genelex KT77s regardless of what anyone says about them, and the only reason I did not do that is I wanted to try separate tube mono blocks with a dedicated ultralinear circuit, double the transformers and power caps instead - with my speakers. Someone really wanted to buy my V12R at the time, and I struggled with selling it. I sold it only to try the monos as an experiment to run with my speakers [trying different amps with my own custom speakers I build/built], to install the exact same caps, and even better Nichicon power caps, and compared from there. Everything was how I needed it on the V12R. Had I kept it, I might have tried KT77s, and once again, keeping bias down to 200-210 per side, max. Sound find, tubes last longer. btw, I’m trying new input tubes this weekend, on the monos to try and model one input tube set I had on the Cary V12R, trying to bring the sound of the new amps closer to what I had with the V12R prior. Just testing, trying, listening.
Oh, and No, I did not want to mess any more with the prior amp or the switchable circuit or trying to un-switch it, left it as is, it sounded great as-is, and decided to move to dedicated ultralinear mono amps. This has been yet another chapter of learning, upgrading, listening and has paid off nicely too fwiw.
