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Perhaps I thought that Bill would address this, but... I certainly am able.
It should be noted for others to benefit as well is the combination of tubes i used for the Jolida sj502a, the power tubes can be maximized by using a variation of the 6550 tubes, namely the center being the v4 and v8, and the ends if you will being the v3 and v7 . I use a for the v4 and v8 the 6550 eh electroharmonix, and for the v3 and v7 use the svetlana 6550c. The result is that the amp delivers lets say the remaining possible best output by using this combination. I found this by accident and was pleasantly surprised. With this combination you seem to get the best of both worlds say.Norm
Succinctly, I found I got more rich and detailed sound , as I mentioned by separating the power tubes. The svetlana's 6550 on the ends and then the eh 6550 , both, in the middle. Incredible lush sound. I have not tried the kt 88's. However, I suspect if one were to alternate them like the 6550's , your output would be for sure richer on octave or two.
Dave, just wanted to let you know the stealth diodes make a huge difference. I don't measure my gear so it could be the placebo effect. I don't care what it is, the sound is much more engaging and less fatiguing even on the dreaded CD's. Thank you for the help you brought my amp up to a very high end sound at a low price. I can't wait to do the phono stage. Parts are on the way.Just so you and your readers know, the latest version of the 502brc has seven diodes. Thats right I found two more sneaky little ones hiding when I took the power supply psb out. It goes like this(I think), two 5408's coming in from transformer, one 1n4007 going to the bias, and four 1n4007's leading to and from a plug with two wires leading to the amp section. I was two diodes short so I guessed at which ones were the least important and changed the rest. I think I guessed right because the sound is great. I have to order the other two today.
Following Bill's remarks on this webpage http://www.responseaudio.com/AboutResponse.htm my believe is that your amplifier may not follow the schematic valid for folks in the USA and perhaps there isn't a trustworthy schematic simply because the components in your amp were chosen somewhat randomly - with VERY poor attention to quality control. This was certainly the case for many Golden Tube amplifiers.
I will ask the dealer about it or check the unit itself.
The .22uF are the actual coupling capacitors. the .47 are signal ground. You will definitely want to start with the .22uF.
I was just going to replace the white SoniCaps with the Platinum. Will that work?