I now see from your photos that my 845S amps are only similar to the 211 types internally. My resistors look as if they might be an upgraded type from the previous model 211/845 amp. As for the Psvane 845 'Hi Fi' grade tubes I am using, I read that they are discards from the Collection Series (T) testing which may have found themselves in the trash bin except that if they are good enough they can make the 'Hi Fi' tube spec. Anyway, I like their sound better that my stock 845B tubes. I added 3 in parallel 0.47/1600V film caps across the 1000VDC rail electros plus a 0.47/600V film cap across each of the two B+ rails. I would have bypassed the -ve bias supply rail too but forgot, and I can't be bothered taking things out again to get to that area. The power supply bypass caps seemed to give a little better focus at the high end and I'm very happy with that mod. I've also replaced the speaker terminals with silver plated brass (they were sold to me as copper!). I use Cat 6 speaker wire (bi-wired) and last night I changed the way I had configured the pairs. The hi end has now become more extended. Previously the Cat 6 exhibited quite high capacitance between wires, however the way I have it now the capacitance is much lower. I guess the next move is to replace the filament bridge rectifier block with some fast recovery diodes. Hopefully this will make the amps a little quieter when I stick my ear in the speaker. There is only the slightest buzz in the speakers at present.
Consonance Opera Cyber 211 mods
I have the Cyber 211s driving Kharma CRMs fe 3.2 and really like them, especially after replacing the stock tubes with the psvanes and using the bpt power supply. I am now ready to tackle the parts upgrade, as there are several blogs out there signing the praises of the vcap cu in the signal path.
I am hoping some one out there has some experience doing that along with changing out resisters, perhaps the diodes, and whatever else, like ps caps and adding bypass caps, internal wiring (likely litz flavored) etc.,
I am looking for a recommended parts list.
I am game to do the r and r myself, but if you can recommend someone in the San Francisco area, please do.
Thank you for the help.
I am hoping some one out there has some experience doing that along with changing out resisters, perhaps the diodes, and whatever else, like ps caps and adding bypass caps, internal wiring (likely litz flavored) etc.,
I am looking for a recommended parts list.
I am game to do the r and r myself, but if you can recommend someone in the San Francisco area, please do.
Thank you for the help.
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- 15 posts total
- 15 posts total