Consonance Opera Cyber 211 mods

For those interested, I finally completed the mods to both Cyber amplifiers. Complete upgrade to the signal path - replaced all caps (2 vcap teflon and 2 blackgates), resistors (20 assorted and recommended by Nick at HiFi Collective), wiring (VHaudio teflon OC copper), Eichman binding posts and RCA), new balanced connector (Furutech), IEC (Furutech), and finally the bridge rectifier (4 diodes also recommended by Nick). I moved the RCA and Balanced inputs to a custom designed side panel to get away from the power at the rear.

I did not touch the power supply (other than the rectifier). As I mentioned before, I did these upgrades in three iterations, the improvements are stunning - with the biggest benefit from the resistors, recognizing that the vcaps are about 2/3 burned in, at about 300 hours or so.

As mentioned above re the psvanes, which I'm running now - I'm ready to find some GEs or RCAs.

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.

Hi.
I Just bought a pair of used consonance cyber 211. This is the first modell, no option for 845 tubes, thought the power card inside are labeled 211/845.
What mods would you recomend me to do to improve the overall sound quality? 
Regards, Kent. 

My Opera Consonance cyber 211 was broken when my Wife let the wire become unpluged.  We have replaced a transform sent by consonance.  but we can not get the Bias to 4.8 it stops at 0.8 and the screw does not advance it.  Does anyone have a diagram of this amp.  Any advice as to what most likely failed??

 

This is a wonderful amp but my adventure in fixing it has taken the most part of a year.  David Mann 239-404-5265