I performed many of the mods on Boyuurange A50 and left with an imbalance that eventual goes away. Did every mod but the front end when my out of stock items get shipped. I only have two things that come to mind are my coupling caps and bias. I am think my left cap is installed wrong as it was picking up noise. I did not fix that issue yet. I did not know about the shielding was performed by placing the cap to the first stage. I still feel that would only be a hum or other noise ingress issue. So last is something I have not gotten comfortable with yet but measuring the electrical circuits of my amp. I will get there. So I just need some recommendations or personal experiences that you may have had with same issue. I can leave a snap shot later of the insides

Hi Everyone name is Bill Fair warning I run on with sentences and come off confusing I'm over excited in this hobby and other electronics. Boyuurange A50 MK III I come from Woo Audio WA234, WA5 LE and WA33 which allows more recs than I care to mention. They even make adapters to use many other like 596. I bought other amps and they did not have the ability for such choices. So back to the amp in question I have not down one mod yet. When can I swap in GZ34? ALREADY DID!! Just educate me please I laid out my question in below sentences and it will be unclear when I do ask as I'm writing this now in experiment method. Stock tube is 4 pin but GZ34 is 5 pin so not clear how I could swap it in. I'd think all pins are used but I have no knowledge yet. I have not looked into 5AR4/GZ34 new stock yet, but I do have matched pair of costly GZ34 Philips on hand. I know they label the two tubes as the same but are my NOS the same? The amp feeds my Woo Audio Wee estat converter which connects my estat headphone and my Def Tech speakers. Notice the stock tubes hum like the dickens and swapped in one of my better 6sn7 now no hum. If the GZ34 are put in and all is quite is it safe to actually play music? After all that I gave up and decided to jump in without looking and all is good. Please explain any stupidity I have and the 4 pin to 5 pin as I am confused. The amp has balls and sounds like a 300B should.