Consonance Cyber 800/845 Valve amps; how good?

Peter, I really don't know the make of the wire in the Cyber series, but while my amps were being repaired (a bad 211 had taken out two resistors and a cap), Exemplar found very poor wire from the inputs to the boards. They also found a metal oxide resistor. They replace both giving a very substantial improvement.

I don't deny that these were quite good sounding amps prior to these changes. I also have the Reimyo PAT777 300B amp using '60s" WE 300Bs. The Cybers are not in this league but do have more control and better bass and dynamics, which may be the result of my using 93db efficient speakers.

My comments about the Rubycon caps, center only on the possibility that they may be fakes. After all these are made in China, which has no control over intellectual properties.

Interesting to see comments on 845 v. KT88/90. They really are two very different experiences, though each can be used in circuits designed around them to deliver good results to the same sonic objective. In both cases, of course, amp-to-amp variance in sound is huge. But as a long-time user of a series of KT88 amplifiers, and current owner of KT88, 845 and 300B PSE monoblocks, I can say there's no general answer to Bartok's question of whether 845 amps are sonically "warm."

The only answer is, "sometimes," or "it depends."

In my experience, KT88/90 amps, whether PP or SE, are quite tunable via tube selection. In my Audiopax 88s, Russian KT88s are dry and relatively lifeless. Chinese KT88/KT100 are fast, wideband and cool. Current Russian KT90s have no advantage. Yugo KT90 Type II and Type III are robust, sparkly, open, fast, with tight defined bass. KR/Tesla Vrosovic KT88s are expressive, revealing of finely-etched details, well-balanced. But NOS British Gold Lion KT88s trump everything with creamy power, excellent bandwidth, low noise, big-T TONE. And then there's the Timbre-Lock adjustment to tweak. I had pretty much the same experience with these tubes in Acoustic Masterpiece and Audion single-ended amps, and in various PP, though in PP the differences were much smaller.

The Audion Black Shadow monoblocks, on the other hand, are profoundly affected by tube choice. The common-as-dirt Chinese 845"A" is unspectacular, dry and soft. The Chinese 845B sounds substantially more robust, nuanced and extended on both ends. Bottom leans to the soft side with some euphonic bloat, but not tubby to the point of distraction on Zu Definitions (lower limit below 20Hz). The later Chinese metal plate 845C, a little light in dissipation, is more like the KT88 -- brilliant and sparkly, with tighter bass than the other 845 variants, but also less drive and Tone. The KR845 is very objective sounding for a big triode tube amp, but sometimes is unreliable. Transients are fast and bold. The new Shuguang 845C, with a full 845 dissipation rating, is rumoured to be excellent when it works, but I haven't had a pair in my system yet. Then there are the vintage NOS RCA and United 845s that cost more than some new 845 amps. Undeniably excellent, in a good circuit they deliver a highly objective sound and softness or bloat can't be blamed on them.

As always, transformers are critical. Given the right tube, I can put a KT88/90 amp in a system and give it triode warmth, and can just as well build an 845 system to have a measure of pentode/tetrode ice.

I've heard the Consonance 845 amps. They are good value for their price.

Phil

Just thought I'd point out that the Enjoy the Music review follow-up mentions that the caps are Rubycons. He's been inside the amps and knows his stuff.

Based on that, and actually the fact that there's no evidence at all that the caps are "fakes", and the sonic qualities of the amps in general, I'd put my money on them actually being the caps they're labeled as.

Could be, I certainly do not have the competencies to say yes or no, but this stuff is from a country with little respect for intellectual property including of it own internal products. Even if they are fakes, they may be good fakes. Perhaps Rubycon were they to have no record of sales to this company would know. I am kind of sorry that I brought this up as it cannot be resolved.

I am still quite happy with the 211 version of these amps with NOS tubes and improved wiring.