Anyone listen to Zu Audio's Definition Mk3?

213,

I heard the Def4 set up by Zu at a Zu party in Atlanta with all Zu wire and what I would call OK gear. Not very good results. Even installed my Lampizator Dac into the system and it didn't even begin to help the sound coming out of the 4. My 2,which was the Def4 pervious owner, far outran the sound coming from his system. The 4 will not out do a 2 with Ford Focus gear and I heard that to be true. My friend was there and when we got back to FL and heard my 2 he was in stitches with laughter as the 2 was so much better.

I find it very hard to believe you heard Atma/ Tenor amps on your Def and that they moved you away.......what Tenor amp did you hear?

You are a good salesman but you are not going to convince those of us that hear huge sound differences when upgrading to, yes more expensive gear.

You can try and explain this away but what we heard will not be forgotten.

Marc,

In most rooms, when you get new Def4s, you should start by running the sub Volume control at max (10) and as the driver breaks in, you'll likely back off from that over time. If 10 is too much just dial in what's right. Then starting at about 48Hz for the hinge frequency on the low-pass filter, experiment. You'll find the right handoff in the 38Hz - 50Hz range, and again break-in of the sub driver may nudge a change.

As with Volume, start with the PEQ Gain all the way up and adjust subsequently. For the PEQ Frequency, Zu's suggestion was to start at 31 and work around that centerpoint for the right balance. I agree with that so far, at least nothing about my room or system argues for finding balance around the extremes. Start with 0 Phase shift. You should twirl this to hear its effect and return to 0, listen, and tune from there if you hear advantage. I'd move from 0 conservatively. Doing initial setup through this order of priority, one at a time, will give you a feel for the acoustic interactivity of the controls.

An analyzer can't hurt -- even some of the iPhone analyzer apps can be very helpful if you are not confident of your ability to get it right by ear alone.

My general preference is to put nothing between the pre and power amplification. I have a *very* high bar for processors of any type to get over to justify making an exception. I haven't heard the QOL nor the X-DREI, though know about both. From people who have heard the QOL whom I know, reaction was that it seems successful in restoring tonal completeness to solid state amps, and that it is much less contributive to a high quality tubes sytem. That suggests that something like the ASR, which has come up in this thread, might benefit from QOL, since that amp sounds tonally incomplete to me irrespective of its resolution. That's not-uncommon problem in solid state still, even as silicon amplification has conclusively evolved past its once-common characteristic harshness. In any case, over decades of involvement in this pursuit, one thing is consistent -- processors generally don't last long in systems, so I'm open to hearing and being persuaded, but I am intrinsically skeptical about lasting value. I expect to hear a QOL for the first time in a few weeks.

As for X-DREI, it's intriguing but if you look at their own data, you can see that the processor alters every category of waveform fed into it. So is it a fidelity device or just euphonic? I don't know until I hear it but it has to be transformative to win consideration from me. In both cases you can buy/try/return so if you're game, go for it.

Last, regarding these two devices and anything else like them: Both companies deliberately obscure explanation of how they work. Both do it under pretext of protecting their IP. Well, in the tech game, your basic obligation is to innovate for value and then run faster than everyone who might chase you. As long as both companies refuse to explain what their devices do to the signal and how they do it, demand will be truncated and their impact on the market will be limited. It's their choice. At least with the Stein Harmonizer H2, the developer says flatly that his device relaxes the acoustic "stiffness" of air. He doesn't explain how, but he's not putting his device in my signal path either. If you're passing my system's signal, tell me exactly what you're doing with/to it.

Phil

Glory,
Being the owner of the Def 4's you heard and being the former owner of the actual Def 2's you currently own, I will totally agree with you that the sound coming from them at the party was awful. They were essentially plopped down in the room with 0 hours on the speakers and all of the cabling in the system, an amp with an output transformer dying(I didn't know it at the time), and a turntable with a ground loop hum. We could have inserted the best source ever made and it would have sounded terrible. However, now that placement issues, burn in and complimentary component matching has taken place, I can honestly say the Def 4's are so far superior to the 2's in every way that 213Cobra has described that you won't recognize them as the same speaker in my room if you heard them again. I have owned the 2's, owned the 2's with the nano upgrade (which is a nice step forward in terms of transparency, micro and macrodynamics) and now the 4's and it's not even close. I would take the 4's with home depot lamp cord and radio shack interconnects over the 2's with unobtainium cabling.
I am sorry that you had to hear the 4's under the conditions you did because the sound was truly awful that day but I can say without question the 4 is vastly superior to the 2 once setup properly and burned in (assuming complimentary components).

I've held out of the fray--but what I can say is my MK4s actually sound palatable with a $600 Onkyo digital integrated. The same combo drove me from the room with Def2s. The reason is the tweeter is more extended, but relaxed--and the mids are cleared up quite a bit by having the new bass driver implementation.

I have a Rives L1 treated room.

KeithR

Glory,

I first heard Tenor amps, pre-Zu and then when I first got Def1.5s, early in the last decade, both their 15w and 75w amps. I have a friend who cycles through high-end gear at whirlybird frequency, including the existing Tenor stereo amp. I haven't heard the $90k monoblocks on Definitions. He brings some of his gear to me because he hears attributes on crossoverless Definitions that he doesn't hear through his Magicos, which is how I heard the current stereo amp. Look, Tenor makes drop-dead gorgeous gear that sounds lovely in isolation.

Now, keep in mind, I have been an OTL advocate in the past. One of the longest continuous amplifier stints in my systems over the past 40 years was held by Futterman OTL monoblocks, hand-built by Julius, which I bought from him directly back in the late 70s. I used those amps for 12 years. So, believe me, when I've listend to Tenor and Atmasphere amps in my Zu-based systems, I *wanted* to like them, and they are certainly quite good in an isolated sense. Both are particularly notable for being "fast" amps that happen to use tubes.

But I have something that changes the context from evaluating Tenor and Atmasphere in isolation, and that is my Audion amplifiers. How expensive does an amp have to be to seem credible to your threshold for "expensive gear?" My Audion Black Shadows are $12,995 per pair and they are the not only the best 845 amps I've heard at *any* price by anyone, they are among the five best amps I've heard, period. But then I have something else: my Audion Golden Dream 300B PSET monoblocks. These amps cost almost $20,000/pr in the configuration I have and can be ordered in configurations up to $36,000/pr. Very few people have them and few here in the US have heard them. But these are the best overall amplifiers I've listened to regardless of price; and yes, used with a speaker with which their power is adequate, I prefer the Audions to Tenor and easily over Atmasphere. They are tonally more complete and musically convincing with Zu Definitions and more so now with Def4. I hear five and six figures amplification more than you probably suspect, and very little of it impresses me. The extreme cost high end in audio generally heads down a resolution vector detached from tonal authenticity, that is unrelated to the way we actually hear music if heard live. This is the central disease of hifi over the last 30 years. Audion's upper tier amplifiers are sonically swift, transparent, dimensionally convincing, dynamic and, best of all, tonally complete.

I don't doubt that you "hear huge sound differences" as you change out gear. Of course you do. The question is entirely whether those huge sound differences are enhancing of or deleterious to convincing musicality in playback. For me, and anyone taking my advice, you are takiing a path that meanders from musical realism *compared to some other options you could take* and which I have taken. But you're convinced of the musical authenticity of the gear you've assembled, so be happy. What does it matter what I think? Regardless, we are talking differences of degree at high cost compared to the gear decision most people have to make.

Generally I've seen very little correlation between most expensive and best, in hifi, so cost doesn't impress me. But best is certainly seldom cheap. We all just decide how much is appropriate. It's not a competition, Glory. Anyone who is attracted to what you describe in cost and sonic consequence, is free to follow. It affects me not at all. I've made no power amplification changes since 2005 in both my systems and I'm only now about to make one preamp change. I bet a lot of people here would like to find that stability in their hifi.

Phil