Anyone listen to Zu Audio's Definition Mk3?

It's hard to argue against any Audion amp to be used with Zu. The Silver Night 300B monoblock power amps are available either as PSET or P-P. 18/18w is fine with Def4. The issue is the bottom end. Look, I have the Golden Dream PSET 300B Audion top-line monoblocks. They are a big step up from Silver Night, with more controlled bass and still, the 845 Black Shadow surpass the Golden Dream on deep bass performance -- and that's after a recap mod to further improve Golden Dream bottom end discipline over stock.

Take your pick based on what's important to you: The 300B PSET amps will have greater ultimate resolution and tone density. The 845 SET amps will have greater drive, more defined and punchy deep bass, and mids/highs will be still meaty, toneful and strong. If you were asking about Superfly, limted to a bottom response of about 30 Hz, I'd say go for the 300B over 845 option. But for Defs, the 845 bottom will underpin a more complete dynamic realism and give you nearly all the midrange magic of 300B SET, with more shove in tonal events and indisputably better dynamic life. If you like maximum presentation of delicate information and don't mind some ripeness in your bass, then by all means choose the 300B PSET. A compromise would be to get more like the 845 bottom end in the 300B push-pull version of Silver Night, but that's at some expense to the holism of SET.

I sometimes use my outstanding Golden Dream pair on my Defs, but by and large, they do tone-drenched duty on my Druids and the 845s put in ceaseless duty pouring watts into Definitions. But if you can, listen to Silver Night 300B vs. Black Shadow, and tell me what you embrace?

I've heard unmistakable advantages to TVCs in place of active preamps on a variety of power amplifiers. On paper, the advantages should be uniform, but in practice they are not. All I can tell you is that I've tried a few high-grade TVCs into Audion power amps. Not even one of those combinations tied with or bested the sound I got from the same Audion amps fed by my extant tube preamps. The combination of TVC + Audion power amp certainly did not sound in any way poor, but compared to other TVC + amp combinations where the resulting sound was a clear improvement, the Audion + TVC combinations failed to satisfy, even sometimes setting sound quality backwards a bit compared to pairing with a fine active tube pre. It's possible that if you rewire the inputs on the Audion power amps to bypass the input potentiometers that the TVC might become preferrable, but then the volume control range and precision may not be adequate, given the high input sensitivity.

You should try it yourself and see which combination you prefer -- no harm will come from disagreeing with me. But if you are asking for my recommendation, my answer is to find best satisfaction, on balance, via Black Shadow over Silver Night, and active tube pre over TVC with Audion power amps, *on Zu Definitions.* If you decide the 300B amp better matches the attributes you value most but you find bass performance the only area of doubt, you can either have a technician perform a recap of the power supplies to improve bass, sacrifice some single-ended tonality in favor of push-pull control, or live with some bass bloat and do your best to tune it out of the Def4 sub via the subs' performance tuning controls. Regardless, these are differences of degree. Any of the Audion amps will be exceptional, and whether to TVC or not to TVC is up to you.

Phil

Hi Phil, once make Def4 purchase I will be auditioning the Audion Silver Knight, Black Shadow, Golden Dream at the UK Audion dealer. This will be fed by the Audion Premier (the only other valve pre likely to be heard other than my Hovland) and Silvercore/Music First TVC preamps, all of these with my complete Hovland HP200 pre/Radia power combination.
I've been so happy with my Hovlands (really upset when they went bust a few years ago), that the Audion gear needs to be a real step up in quality for me to consider parting.
I get the impression from your previous posts that you're a fan of the Hovland sound, and prefer it to the ASI Emitter/Tenor items mentioned.
What would you describe are the major contrasts in sound characteristics between your favoured Audions, my Hovlands, and my likely third and final alternative, the Dave Berning ZOTL pre/30w power?
Finally talking about not being to fully use second half of available volume settings on my pre, and use of attenuators, do you have any opinions on stand alone buffers that vary impedance/gain which source components are connected to, with the buffer then feeding the pre amp, esp Burson Audio AB 160 and Eastern Electric Minimax BBA?
Marc

David, will do.

Marc,

You'll need to spend some time on that range of auditions. I missed mention in your earlier posts that your Hovland power amp is the SS Radia and not the EL34 push-pull amp. If you haven't spent serious time with a high-grade SET amp, it would be enough of an adjustment to evaluate one agasint a push-pull tube amps, but in this case you're making the comparison of SET v. a very good SS amp. So give yourself some time to assimilate the differences you'll be hearing, and process what's meaningful to you.

Some things are a one-way street. Since experimenting with SET and SEP amps some years back and settling on a very high grade instance of SET amplification, I am unlikely to ever own a push-pull tube amp again -- especially one of high power output as long as I'm using efficient Zu speakers. Once you've given up the tell-tale crossover grunge in a push-pull amps -- which isn't obvious or so bothersome until you jettison it in SET -- you tend not to want to go back to it but instead pursue better SET. One of the few push-pull tube amps still satisfying for me to listen to is the Quad II monoblock pair, in either restored vintage form or the current Asian reissue, and ther reason is the circuit is about the simplest available in that topology today. You don't mind what it doesn't have, and you appreciate what it does correctly. What you will get from SET at the level of implementation in Audion Golden Dream, Black Shadow and even Silver Night is speed and tonal completeness that you usually have to trade one to get the other at Audion's transparency.

The vast majority of solid state amps are push-pull, but some are Class A, and there are a few single-ended transistor amps, as Nelson Pass is issuing, that present some interesting competitive developments. Lavardin's work in curtailing "memory distortion" in silicon devices yields an unusually musical solid state amp. McIntosh autoformer-output and quad-differential solid state amps are good options for some systems. But none of these options so far, for me, matches the tonal completeness and holistic presentation integrity of very well designed and implemented SET. I'm certainly open to any of them satisfying me in the future.

This is a long way of saying that while the Hovland Radia is a great amp, it might have worked for me back when I was still using low efficiency 2-way or 3-way crossover speakers, but I am down a path I can't return from in terms of being satisfied by that sound again, given what I listen to now. Whether you agree or not will be learned in your auditions. I'll only add that whatever you hear in the Audion amps, can be improved through tube ugrades, but the fundamental amp characteristics are going to be fully present, stock. That said, I'll say the Tenor and Hovland sounds are closer and to me more "correct," than ASR.

The Berning ZOTL is a very clean tube amp, and as I mentioned in an earlier post, it handles event changes with speed and alactrity. It's a good amp. The ZH-230 is a push-pull design, so it has better bass discipline than most SET amps and sounds open and linear, like a wideband push-pull amps should. Good as it is, it sounds tonally incomplete to me -- favoring ultra-definition over holistic presentation. The Audion amps -- especially the silver-content ones -- have the speed but aren't underfed instrumental tone and "correct" human voice. On the other hand, the Berning will sound more like what you've been listening to in your audio past, but with more beauty. The Hovland Radia will have the events, "the consonants and the vowels", in music present but compared to the Audions will sound emotionally bleached. The intellect in music will be illuminated but heart will be more remote. Of all those amps, the only ones that get electric guitar tones truly, authentically right, are the Audions, and Zu speakers are ultra-competent at revealing this. And then once you grok that, you begin hearing the same authenticity in other strings, and in brass, and in voices. Tonally complete is how I think of it.

Buffers are antithetical to system simplicity, so I'm not interested. Get the impedance chain right in the gear you put together. If you buy Audion amps, you will have input level controls, and gain matching will be easy. You have no drive issues if you keep your excellent Hovland pre, or move to Audion. And with those amps, even the TVC will be fine, if that becomes your winning preference.

This is how I see your choices. Others may disagree.

Phil

213,

Are you running your gear straight into the wall with no conditioner?

Also what to you set your components on?

One last question. How do explain the Zu crossover-less design?