Anyone listen to Zu Audio's Definition Mk3?


Comparisons with the 1.5s and the others that came before? Getting the itch; again......
128x128warrenh
German boxers,
The Clayton class A amplifiers are about as good as it gets for very high level SS amps(regardless of price). Your example reminds me of my former Symphonic Line ownership.Some people will just prefer tubes to SS and vice versa of course.In your case OTL seems to fit your desires, for phil and myself SET is preferred. I`m not sure how glory`s experiences will impact your own 25 years in this hobby any more or less than phil`s or anyone else for that matter.(I`d assume by now you know what works for you). For every person who`s migrated from say low power tubes to finally settle with high power SS, there`re just as many who went in the opposite direction to their ultimate satisfaction.

Glory selected the ASR Emitter over all previous tube amp types in his system. On the other hand phil rejected the ASR in favor of his Audion SET. Simple point, it`s pure subjective decision making. There`s no ultimate superior amplifier just many individual preferences. Thank goodness we have such a varied pool of amplifier types to choose from.I like the OTL amps I`ve heard but I just like SET even more so, you may be the reverse.
A good tube amp(particularly SET) in my personal experience sounds more like the 'real thing'. At lease for me SS amps in general tend to remind me I`m listening to a 'stereo system' and are less convincing as providing that 'live' feel and presence.But hey that`s just me. I wish you the best.
Regards,
Germanboxers, I did not choose my terms correctly. By 'holy grail,' I did not imply that your quest for 3D tangibility was mystical or unrealistic. I meant to say that it was the essence of good audio: convincing audio illusion. I have heard very few systems pull it off regardless of amplification, etc. I too have made inept, stumbling attempts at system building while chasing various sonic attributes.

I have a few friends who own Claytons and love them even on higher efficiency speakers. That being said, they have also been described as being "darker sounding" for class A SS, and that may be part of the reason why you like the Atmas better. Believe it or not, many people felt the older generation ASR amps were too dark sounding. Go figure. I do know that using SS amps can make life harder in terms of achieving synergy and good sound. Tubes are much more forgiving particularly with a digital front end and high efficiency speakers. I briefly experimented with the Emerald Physics CS 2.3s, and high powered SS (TRL Samsons) was not copacetic.

You have already cobbled together a nice system. No need to chase a lot of new variables. The one variable worth investigating is the new secret sauce in Gary's system, one that produced exactly what he (and it appears you) were looking for: Dale Pitcher's new conditioner.

It is supremely irritating that you cannot email members any longer.
Phil,
Thanks for your reply,
My Coincident SET amp and speaker are fabulous together as would be expected with the same designer. I find your experience with the DEF MK IV. very interesting and I`m attracted to well implemented simplicity.In general simple designs sound better to me than the complex designed components.The crossoverless speaker should in theory sound pure and have natural tone. I`d really like to hear this speaker one day.The Frankenstein very easily drives my 3 way(2 xover speaker) it should be able to drive the even simpler DEF IV.
>Charles1dad - "In your case OTL seems to fit your desires, for Phil and myself SET is preferred"<

To this point, OTL has been my preference on appropriate speakers; however, in fairness, I have only tried one SET with the Zu's in my room. The Melody 300B SET mono's were definitely not an improvement even over a modest Marantz SS integrated, much less the Atma M60's. That being said, the most beguiling sound I've heard was in a dealer showroom with Proac Response speakers and Cary 805 SET. So, I suppose I'm holding out hope that the right SET can bring me even closer to the music?

>Agear - "By 'holy grail', I did not imply your quest for 3D tangibility was mystical or unrealistic"<

I think I know what you meant, though it's elusiveness for most of us certainly makes it seem "mystical" at times.

>Agear - "I too have made inept, stumbling attempts at system building while chasing various sonic attributes"<

I could not have described my own pursuits at times any better. It is this concern with "sonic dead-ends" that makes me cautious about wholesale changes. Within the last few months, I toyed with the idea of buying the Coincident Pure Reference Extreme. On paper, it seems to have much of what seems to work for me (easy to drive, full range, simple crossovers) with the potential for improved 3D soundstaging and the possibility of finding the "holy grail" with the right amp. Unfortunately, I had to stop the insanity and recognize all the things that I absolutely love about the Zu's. The potential for chasing a few possibly better sonic attributes while unknowingly (at first) giving up some of what I love from the Zu's is too big of a risk for me. Make sense?

>213Cobra - "Start with your Atmasphere and draw your own conclusions. It's a great combination to begin knowing your next move, if one is warranted"<

If I understand you correctly, you are saying to experiment with amps, presumably good SET's, and determine if this is the correct path for me? That is, indeed, what I am thinking of doing.

Phil, I've read much of what you have written on the Audion 845 Black Shadows in this and other threads. I've researched Sophia, Audion, Cary, and Mastersound 845 amps fairly thoroughly. From what I have read, I think the Audion may be closest to what I'm looking for, IF SET is what I'm looking for. Does that make sense? Are there any distributors in the US that would allow an in-home audition?
Germanboxers,
I understand your point,the Melody 300b SET could just be a mediocre SET amp. There`re so many 300b amplifiers available in the marketplace and at all levels,from sublime performance to poorly implemented.As expected transformer,power supply and parts quality can make or break a SET(or any amp for that matter). Gon member Morganc for example uses my amp with his Zu speaker and seems to love it(there`re certainly other upper quality SET choices), Phil makes a very strong case for high quality 845 based amps. It`s great to have viable choices. That 3-D magic you seek is certainly there with my Takatsuki-300b tubed Frankenstein/Coincident speaker(in abundance). I have no doubt that this is also very possible with your speakers.
Regards,
Germanboxers, your approach is wise. Keep what you have and take small steps. I have close to 15 years in the "high end" of the hobby, and an embarrassing percentage of that time has been spent going either backwards or sideways. And that is despite being rigorously "scientific" and disciplined in doing blinded listening sessions, "research," etc. The only reason I am where I am now (temporarily?) is dumb luck or grace depending on your perspective. What a goofball hobby.

All that aside, I was wondering about what you are "not" hearing currently vis–à–vis your sonic memory of that glorious sound? Is there a single variable that you are able to pin down? Do you think the Atmas are a tad too lean? Your source? Do cables make much of an impact in your system? Speaker positioning have much influence (as Phil suggested)?

For me, I have become more primitive or foundational in my approach. I am fixated on power and the room. I think dropping the noise floor in a system can improve dimensionality but cannot necessarily bring that fleshy palpability. I know for Gary, he was able to achieve those two things through cables and "conditioning" rather than adding another set of tubes. You guys should dialogue as you have owned similar gear and seem to have a similar sonic bias ([email protected]).
Agear, couldn't agree more. My noise floor has really dropped using a standard industrial grade balanced power transformer, I now get that 'after midnight' sound ALL day long. I live/listen in a very dirty power area, surrounded by mobile booster stations/heavy industrial power useage etc.
Additionally the Black Hole bass attenuator has dramatically improved detail threshold in my room.
These two items esp. balanced power have done things NO component upgrade, no matter how expensive, could have acheived otherwise.
Power rules!
>>Agear wrote: <<
All that aside, I was wondering about what you are "not" hearing currently vis–à–vis your sonic memory of that glorious sound? Is there a single variable that you are able to pin down? Do you think the Atmas are a tad too lean? Your source? Do cables make much of an impact in your system? Speaker positioning have much influence (as Phil suggested)?

The Zu/Atma-Sphere combo was a huge step forward in the area of "tone density", dynamic and tonal shadings, and macrodynamics compared to previous systems. That said, and ignoring for the moment the aural 3D processing Phil mentioned, I "think" that what is missing is additional weight/density in the lower midrange (WITHOUT lessening transparency) and additional "air" on the top. Of course, I'm not entirely sure since there are likely other elements that conspired to give that "glorious" illusion in addition to the frequency related ones mentioned above. I'm hopeful that the MkIV's add some of the "air" and I'm considering if the appropriate SET can provide the lower midrange tone density without lessening transparency.

For power I have a dedicated 100 amp subpanel with 4 dedicated lines and run a PS Audio Premier as well. I did the dedicated subpanel with an eye toward possibly placing an isolation transformer between the main panel and the sub, but have not followed through with that option yet. Not entirely sure how to handle grounding...main reason I haven't completed that.

My source is the Metric Halo LIO-8, fed by a Macbook pro and Pure Music software. I've had alot of sources prior, but the three best were: MH LIO-8, Berkely Alpha, Esoteric UX-3 with Statement mod from Steve Huntley of Great Northern sound.

In a head-to-head in my current system, the LIO-8 was far superior to the Berkely Alpha, both fed directly to the Atma Amps. The Berkely was fed by my Windows XP music server via Media Monkey and Lynx AES Digital Soundcard (all .wav files) and the LIO-8 was fed by Macbook Pro via Firewire and itunes/Puremusic (all .aiff files converted from .wav files above).

The Esoteric was outstanding in a prior system, but I had sold it before going the Zu route so no comparison was possible. Incidently, I did extensive testing with the Berkely both in to my Atma-Sphere MP1 MkIII preamp and direct to the amps and found direct to the amps superior. This was the first time in my experience that direct to amps was superior to having a good preamp in between. As a result, I sold my MP1 and freed up some cash...always nice.

The system is not too sensitive to cables, though differences are clearly heard. Just tried some Iso-Clean speaker cables and after a month or so of "playing" decided my Zu Ibis are preferable. The Iso-Clean cables did bass outstandingly, but seemed to lose a smidge of inner detail and top-end air in comparison...not a direction I want to move.

Positioning makes a significant difference in my room, but not as much as some other systems in other rooms that I've had. In a way this makes it harder because differences between great and ok are not as evident so tend to not spend as much time worrying about it (good and bad I suppose, but mostly good from my standpoint...less audio neurosis).
>>If I understand you correctly, you are saying to experiment with amps, presumably good SET's, and determine if this is the correct path for me?<<

I think a subset of high-quality SET amps -- particularly 845 based -- are ideal for Definition systems, but you already have a very fine amp in the Atmashpere OTL so you should begin with that; get accustomed to the combination and see how it satisfies you. Once you have that baseline, then try Audion, Sophia or maybe Melody or Consonance 845 SET amps if you find you still have the appetite for trial.

>>From what I have read, I think the Audion may be closest to what I'm looking for, IF SET is what I'm looking for. Does that make sense? Are there any distributors in the US that would allow an in-home audition?<<

The US importer/distributor for Audion is Gary Alpern, reachable at his web site, http://www.trueaudiophile.com. The unfortunate state of high end audio retail is such that the usual burden is on the prospective buyer to find a way to hear the gear they are interested in, or find home trials from online sources. I don't know where you live nor how far one of Gary's retailers is from you, but start by asking him.

Phil
Germanboxers,

Which AS were you using? I used an S-30 with Soul Superflys and disagree strongly on the "tone density" thing.

That was the area to my ears atma was weakest. Transparency, resolution, low bass extension--I'll concede those things.
>Gopher wrote:
That was the area to my ears atma was weakest. Transparency, resolution, low bass extension--I'll concede those things.
I use the M60's and if you read carefully I said the "Zu/Atma system" moved me in that direction, not Atma alone. And I suppose I should qualify that technically the Melody 300B SET monos I owned had greater "tone density", but were thick as mud and severely lacking in transparency relative to the Atma's. I wouldn't say the Melodys moved me in the direction of "tone density" because they gave up so many other things most of us, but especially me, value in our music listening.
I didn't miss that--I just assumed Zu speakers were a given as part of a system as this is a Zu thread.

Thanks for clarifying, I can appreciate those observations. Interestingly, I'm using a Melody KT88 integrated myself these days which I like, but it is cleaner, more linear tube then the 300B, imo.

Enjoy your pairing! There is nothing wrong with Atma-sphere. :)
I also think I liked the Atma/Zu combo better than Gopher, who went from the Atma to an 845 amp, that I am pretty sure provided even more tonal density. I was coming from SS amps and with the 6SN7s I used (Black Treasures, RCA, and a couple others) I had tonal density that I was very pleased with. But it is always going to be a matter of personal preferences and system synergy.

A great combo, if that combo matches well with your prefs as a listener.
GB,

My source is the Metric Halo LIO-8, fed by a Macbook pro and Pure Music software

Had the Atma/Amarra #4 Dac running with a MM/PM and Zu Presence speakers.

Atma amp moved me closer to real live music than any of the SET amps I had in my system. The MH 8 is a great dac.

I found the MM running with a LPS to be a noisy little guy killing all my attempts to go to the next level. I had to by a Lampizator transport that took the MM out of transport duties. Now all is dead silent in the system.

To complete the final piece I grabbed a Dale Pitcher Power Bridge that was, to me, a true breakthrough in AC power supply. The Power Bridge makes my Def2 the Def10 SE SA. It runs my transport/Dac.

And cables are the last thing to worry/ get right. The PB will make that thought sound silly.
Glory wrote:
Atma amp moved me closer to real live music than any of the SET amps I had in my system. The MH 8 is a great dac.

Agreed on MH LIO-8. I've only experimented with the Melody 300B SET mono's and, at least in direct comparison to the Atma's, the lack of transparency, lack of speed, and general "mudiness" was not for me. On the other hand, prior to buying the Atma's and Definitions, the Melody was a nice amp on my Druids, bettering my Marantz integrated in most areas, but not all. On the Definitions, unfortunately, it was quite a different outcome. Perhaps they just couldn't handle the 6 ohm nom load of the Defs, yet the Atma's could? Go figure.

Glory wrote:
I found the MM running with a LPS to be a noisy little guy killing all my attempts to go to the next level. I had to by a Lampizator transport that took the MM out of transport duties. Now all is dead silent in the system.

I'm not following this? What is the MM and the LPS?

Glory wrote:
To complete the final piece I grabbed a Dale Pitcher Power Bridge that was, to me, a true breakthrough in AC power supply. The Power Bridge makes my Def2 the Def10 SE SA. It runs my transport/Dac.
The Power Bridge runs only your transport and Dac? And it made this big of a difference in your opinion? Have you ever tried the PS Audio Premier or other reconstituted power devices? Seems from a noise/isolation standpoint this would be far more effective? Color me curious.
Gopher wrote:
Thanks for clarifying, I can appreciate those observations. Interestingly, I'm using a Melody KT88 integrated myself these days which I like, but it is cleaner, more linear tube then the 300B, imo.

One thing I have overlooked is that the Melody 300B did work well with my Zu Druids, a 12 ohm load versus the Def's 6 ohm load. I never did do a Atma/Melody comparison on the Druids, but my gut tells me the "winner" would have been the same, though perhaps not to the same degree...not really sure.

Gopher wrote:
Enjoy your pairing! There is nothing wrong with Atma-sphere. :)

I hope I didn't come across as argumentative? I do notice that when responding to threads with an ipad my tone sometimes comes across like an impetuous child. It takes so long to type with a single finger (or two) that I tend to shorten, and perhaps, coarsen, my words.
>>One thing I have overlooked is that the Melody 300B did work well with my Zu Druids, a 12 ohm load versus the Def's 6 ohm load.<<

300B amps can be a great match to Druid, standard Omen and any other Zu speakers with a lower limit of roughly 40Hz or above, regardless of impedance. But sufficient execution of 300B SET topology, especially in OPTransformers and power supply size, stiffness and regulation, to maintain linearity into the deeper bass regions Definitions can attain is generally a more expensive proposition. I've heard Melody SET gear, but not their 300B amp so can't comment about its suitability for Definition specifically. I have however heard very good bass from 300B SET on Definitions, in the form of the Coincident Frankenstein monoblocks, the Audion Golden Dream PSET monoblocks (recapped specifically to improve this) and the novel Butler current dumping implementation wherein a single 300B per channel primarily governs sound quality in tandem with a muscle amp. DIYhifisupply has an interesting 300B amp in a similar complementary scheme with a "muscle SS amp" and in that case, the amp is switchable between pure 300B SET operation at 7/7w, or fusion operation at 40/40w. I haven't heard this amp but having heard some of their other reasonably priced tube gear, there is reason for optimism this may be a very effective affordable triode amp for Definitions.

Further, I've found the KR Audio 300B tube to significantly contribute to more controlled deep bass quality from many 300B SET amps, though some of the hardness it contributes to bass discipline can change the midrange and treble euphonia some folks seek from their 300B amplification, from lush to a more aggressive punch and slam at some expense to midrange tone density. I happen to have found the right optimization for that tube in the recap of my Golden Dreams that also improved the objectivity of the Sophia mesh plates, correcting their euophonics while also leveraging the KR Audio's assertive discipline while dialing up their beauty and tone.

300B amps, if optimized for good linearity at full bandwidth, can be stellar revealers of the obscured musical event, so shouldn't be overlooked. It just may be a more expensive proposition to get the right match of amps/tubes/speaker than many people hope.

Phil
GB,

Mac Mini = MM

Linear Power Supply = LPS

Going direct from my Amarra Dac to the Atma was a clear and dynamic sound but I lost 3D/tone/ and the emotional side of the music. When I changed Dacs to the Lamp L4 tube Dac I could run direct with no problems.

The Power Bridge will cause you to realize that it is a major breakthrough in AC power supply for digital playback. When installed on my Transport/Dac I listed and sold my Running Springs DMitri on the same day.

If you want to demo a PB let me know.
In response to this amp emphasis on the Zu thread, I'm currently running my Zu Def2's into a Hovland HP200 tube pre amp and Hovland Radia 125W/ch dual mono power amp (both unavailable, Hovland actually sadly having gone bust some years ago).
The combination is v.beguiling and true to source. I am v.confident that the Def4's will sound great thru them, but in due course would love to try an all-tube amp chain, either the Audion Black Shadow 845 SET 25W/ch, or the Dave Berning VOTL combination.
I have taken Phil's advice and tried -10dB attenuators on the termination of i/c's between tt/cd and preamp. This is now allowing me to turn up the preamp so I get the same volume at 2o'c instead of 11o/c. The result is much more presence thru the midband and an increase in bass heft. $30, no contest!
Germanboxer,

Not at all. I just didn't want to come off as if I was insulting your amps. They're very good, some of the best sound I'd heard with my Zus technically. They didn't click for me emotionally, but I respect the hell out of them and am not surprised they're winners on the new Definitions.

When Glory referred to MM he was referring to a MacMini, a small all in one computer made by apple that a lot of guys use as music servers. He replaced it with a Lampizator transport which I had the pleasure of spending a week with a week ago. Its a damn fine piece! Its an EXTENSIVELY modified Squeezebox Duet with tube power supply and tubed SPDIF out which is quite unique... I'm working on a little something with a digi-lampi kit (tube SPDIF out) myself at the moment.
Phil,
Very good advice for those who may be interested in the 300b amplifier route(strong,over built power supplies and transformers). In terms of the output tube for superior bass weight,impact as well as control/firmness and articulation= Sophia Royal Princess and the Takatsuki -TA 300b. these two do it all from bass to treble,they`re superb but very expensive unfortunately(they do deliver the performance!).Both are supreme, Takatsuki just a bit better.
SpiritofMusic, when do you expect your Def4's and when do you plan to audition the Audion or Berning amps?

Glory, thanks for the clarification...if I was on Computeraudiophile, I'd have picked it up immediately, but since so few here seem to use computer audio (yet) the acronyms went right over my head.

Thank you to all who have answered my questions...lots to digest. I plan to work on some basics, some amp stands (Atma's are setting on a cherry shelf which is laying flat on a tile floor, and speaker positioning as I wait for my Def4's (probably a month or so).

After I optimize what I have and enjoy/get familiar with the Def4's for awhile, I will inquire about auditioning an Audion or Sophia 845 based SET. This seems to be a fundamental question that begs an answer...will the right SET do it for me or am I a hopeless OTL lover? If SET is it, I probably won't sell my Atma-Sphere's...just really loved what they've done for my musical enjoyment in so many different systems. I'll keep them as my 2nd set of amps should I desire a "change up" from time to time...unless, of course, the SET experience is truly paradigm-shifting I suppose. Never know till you try.

As some of you receive your Def4's, please keep posting here...we've got some great commentary already from GSM, Cobra, and others. It'd be a shame if others didn't share their thoughts/experiences with the Def4's. Besides...I'm stuck getting my fix vicariously for at least a month...help an audiophool out, would ya?!! :-)
Beautiful dogs you have GB.

The Pic of Samson sleeping is the 845 in action and the outside pic of the dogs alert and ready for action is the OTL in action.

Sorry I just had to write that. All in fun boys and girls.
Germanboxers, hang on, I'm still working 24 hrs a day and 7 days a week to get it together! Seriously, I've just received paint swatches from Christian at Zu and need to make a final decision re finish. I was set on Gloss Black similar to that used on the Def4's shown at RMAF '11, but I'm swinging towards Cosmic Carbon which is a sort of flecky metallic grey which will look different in different ambient light conditions.
If cash flow goes ok will be looking to order next month and receive in June/July.
Re amps, I'm not in a hurry to change, so auditioning Audion/Berning is not first on the agenda, but upgrade to turntable definitely is, and I'll be moving away from belt drive to either idler (Trans Fi Salvation/Terminator T3Pro linear tracking arm) or direct drive (Inspire Monarch or Brinkmann Bardo).
I will definitely post experience on the Def4's when there's something to say.
Glory

Interesting as I thought his BPT was good from what I've read. I made my own and have had great results with it.

It was fairly inexpensive to build too.
Paid $500.00 for my BPT LPS. I bet you made your unit for $175.00. Running a MM for a MS is OK but one can do much better.
I've replaced a $6000 audiophile power conditioner with a $600 standard industrial balanced power transformer. Night and day difference.
Currently settling on Cosmic Carbon as choice of finish for Def4's. Hope to make a decision to buy in the next week or so.
Everyone's thoughts on this choice?
Germanboxer, do you think reinserting a tube pre-amp would ameliorate some of what you are missing, particularly lower midrange density? I know you have already done that experiment, but...

I researched the Halo along with Prism Orpheus as possible DAC/pre-amps to front an Emerald Physics system. The word on the street at that time was that the Halo was more lean and mean but "true to source." The Orpheus was a little fatter and more euphonic. I never heard either, but that was what I was told by folks who had done the shootouts (whatever that is worth). I also dialogued with Barry Diament (well known recording engineer) and he used the ULN-8 in his studio and loved it and felt it was very true to source. No embellishment. That aside, I know many feel that the Metric Halo and Berkeley dacs are too "digital" sounding and converted to tubed products like the Lampizator. Gary felt that way even with the Atmas and later Tenor OTLs in place.

Then there is power (and Spiritofmusic, it rules indeed!). IMHO, that has more impact than people realize especially in terms of 3D presentation and even making things more "analog." I know the ULN-8 has a switching power supply, so I wonder about its effect on the sound and/or its potential imperviousness to power cords, conditioners, etc. Barry Diament told me that he experimented with tricked out linear supplies on the Halo and it did not make a hill-of-beans difference. So, I don't know what to say on that one. I "think" or "know" that dropping the noise floor and dealing with ambient inerference (RFI, etc) is important. I played with isolation transformers briefly (Topaz) with my EP system, and they had an undeniable effect. More clarity, dynamics, etc. I think they are a grand idea if you live in a crappy hood with lots of external garbage like industry, etc. Some people (who made use of transformers in the 80s) felt that they have a "sound" (which I think I heard) and can limit dynamics. I do not know or pretend to understand the technical particulars behind that. Another area of interest for me is grounding schemes. I have audio buddies who own the Tripoint Troy grounding system and cannot live without it. I also know several people who have made use of ionic grounding units in their homes, and they are purported to drop the noise floor significantly through grounding of your subpanel, outlets, and even the chassis of your equipment. One friend told me that an the sound of an average tuner improved dramatically! I will be trying this myself in my listening room that is being built as we speak. Then there is Dale's magic box, but more on that later in a different forum.

Don't forget your computer. While being a great source from a utilitarian point of view, it is a rats nest of noise and interference. There is a lot you can do, including linear supplies, shielding, hacking the programs that operate in the background, etc. MachI is one outfit that does mods. Here is a good discussion of some of the issues at hand: http://www.lessloss.com/page.html?id=45

Finally, I do hope you find bliss in the 4s and the right amp. That would make things a lot simpler and this meditation null and void.
Spiritofmusic,

OT, but what $600 balanced power unit did you purchase? And did you plug your amps into this or keep them straight to the wall?
Spirit,

I've replaced a $6000 audiophile power conditioner with a $600 standard industrial balanced power transformer. Night and day difference.

What 6K PC did you get rid of?
So I have had a week of experience with the latest chassis Sophia 845 monoblocks. They are beautiful to look at and seem well built at 50+lbs each.

Impressed thus far. Big, big sound and probably the most dynamic tube amp I've had in my system (please scroll up to find a long list of them). Have not tube-rolled as of yet, but that will be coming once broken in. Historically, I have not liked the B tube that so many recommend (sounds closed-in to me). The amps are lively and extended- and not the warmest out there. Compared to the Audions, I'd say the Audions have probably a bit more tone, but less drive/dynamics. Noise on the amps is very low for SET and I feel will be even better once burned-in/optimized.

The amps are the only ones I've heard that do strings as well as Shindo--which says something. SET spooky midrange of course is there. Only negative thus far is a bit of midrange glare, which I believe is Chinese tube related. Have a pair of RCA NOS 6ns7s that I will drop in soon.

Bass is quite good, but not Mac 601 SS depth. This is to be expected.

Keithr wrote:
The amps are the only ones I've heard that do strings as well as Shindo--which says something. SET spooky midrange of course is there. Only negative thus far is a bit of midrange glare, which I believe is Chinese tube related. Have a pair of RCA NOS 6ns7s that I will drop in soon
When you say they do strings well, are you referring to bowed, or plucked, solo or massed? I'm curious if the langauge you used is meant to convey excellence in timbre, harmonic richness, transient capability, inner detail or possibly all of the above and more I didn't list?

How bad is the midrange glare? Definitely curious if this is wholly a tube issue or just mostly mitigated by changing tubes.

In an earlier post you made, you mentioned you had tried the Audion Black Shadows, but they were very noisy. Phil then replied stating the problem was found to be a failed bridged rectifier (or something similar?) and stated another audition would be undertaken along with the Sophia? Do you still plan to compare the Sophia and the Audion? Thanks!
plucked strings- there is a rightness that is tough to describe.

the midrange glare is pretty muted. i'm being very picky here. 213Cobra feels the A tube is the reason behind this. i think the cheap input tubes are the reason. we shall see.

I've heard the Black Shadows 20+ times over the years. well aware of their sound. comparing the two head to head may happen, but it's not a priority. in fact, it's not particularly of significance to me as I chose Sophias over Audions and others.

KeithR
Keithr, do the Sophia's still use the 206 driver tube? Are the amps tube rectified or SS...do you have an opinion on the differences between the two? Having a difficult time finding up to date info on the Sophia's. Thanks!
Agear wrote:
do you think reinserting a tube pre-amp would ameliorate some of what you are missing, particularly lower midrange density? I know you have already done that experiment, but...

Well...I was fully in your camp on this issue several years ago. My friend and I listened extensively with and without a good PRE in the system with both my Audio Aero Capitole CD player and his Resolution Audio Opus with Ref mod from Steve Huntley at GNSC. At that time, even with the SS Rowland Capri pre, we both preferred the sound WITH a pre in the chain.

With the Berkeley, using an Atma-Sphere MP1 MkIII pre with V-caps and caddock resistor package, we both preferred the Berkeley direct. What's more, anyone who has lived with an MP1 MkIII will attest that it is incredibly transparent, musical, bold, neutral with the exception of a slight emphasis in the lower midrange, yet we both preferred it direct.

Agear wrote:
I know many feel that the Metric Halo and Berkeley dacs are too "digital" sounding and converted to tubed products like the Lampizator.

I could understand how one might come to that conclusion, particularly if they use some of the "ultra resolution" type speakers/equipment that masquerade as "neutral", but sound leached of body to me. I don't find either the Berkeley or the LIO-8 remotely "digital" sounding, but the LIO-8 was more "real" sounding to me. I happen to agree with Barry Diament that the use of a switching PS is not a disqualifier for top performance. Every design is greater than - or lesser than - a sum of it's parts. BJ (Metric Halo) knows his stuff and I judge this solely on the quality of sound it delivers. Trust me...I have a little vanity in me and if the LIO-8 wasn't outstanding, I'd have irresistible desires to find a more "high-end looking" source. It is butt-ugly, but it sounds wonderful!
Keithr, you mentioned Sophia's "latest chassis". Have they changed the "form factor" from wider and shallow to narrower and deeper? Thanks!
germanboxers, the speakers definitely influence the final result. I agree. Acidic detail machines would not work with your paradigm.
The Sophia 845 current chassis are 206-driven and tube rectified. I don't think they offer the 6sn7-driven version (at much lower cost) anymore.

When both versions were offered, the gulf between the 6sn7 and 206 versions was very wide. The 6sn7 version of the Sophia 845 was a fine amp but not exceptional. The 206 driven circuit is much more energetic and toneful. Like most amps that are tube rectified, the tube rectifier is a real point of tunability, with substantial effects on dynamic performance, macro/micro dynamic perceptions, tone density and degree of slam.

Phil
Form factor changed a couple years ago. The current website shows my amps as they appear in front of me. The new chassis is much larger with no wood caps.

I have only seen "old chassis" versions appear on Audiogon, hence the reference.
FYI- I believe a Berkeley run direct to go tube amps is a stellar combo (if you don't do vinyl)

That is my current setup, though will try a Mac C2300 preamp in front after the amps are broken in.
Keith, other than the Mac and current amps, what others have you tried on the Zus?
Keithr,
I believe your DEF IV and Sophia 845 SET pairing will provide you with stunning musical realism and 'natural' beautiful sound. In terms of resoulution,nuance,tone/timbre and dynamic ebb and flow you will have sublime results. I look forward to your future impressions.
Regards,
Glory, I'm disposing of a Burmester 948 conditioner, superior, to my ears at the time, to the Audience, PS Audio and Isol units that I auditioned. Sound quality was much improved wrt to standard mains re tonality and noise floor, but dynamics always appeared a bit 'pinched'.
On installing a decidedly non-audiophile standard industrial grade 4kV (and in my opinion it shouldn't be any less than this) Airlink balanced mains transformer, all the positive attributes of the Burmester were maintained, with unrestricted dynamics. I now love listening to music thru the day, with v.little improvement after dark.
There are two caveats to this; one, it took 4-6 weeks for the treble to open up from an initially hard sounding start, attributeable to the 60+lbs of copper in the transformer burning in; and two, upgrades are always system dependent, but in my case with really corrupted mains quality in my area, upgrading power has always taken precedence over equipment supports etc.
My Airlink has 2 outlets, from each I run an 8 way multi socket, and plug audio and video components into these.
I believe Airlink is a UK provider (230v) only, but there will be companies in each country that should supply locally.
After a period I may investigate a Westwick pro studio unit that uses 150lbs! of copper in its 8kV unit that may provide an overkill solution to mains contamination. In the USA I believe Torus provide a similar level of engineering.
As a point of reference in the past the Definition was a 6-ohm load and inappropriate for the Atma-Sphere S-30 although the M-60 was fine with it. Zu offered the Definition in a 30-ohm edition that by all reports was an excellent combination with the S-30.

The newer versions of the Definition seem to be an easier load and I was told be Sean at the 2011 RMAF that there is a switch that can set the speaker to a higher impedance.
So boys and girls, I am taking the plunge and hoping to order Def4s by end of week for a June/July delivery.
I'm veering towards Cosmic Carbon, a little different from the standard black I always end up buying.
This has been a tight decision for me, since use of balanced power and Spatial Computer Black Hole has really sorted out long term bass integration issues with my Def2s, but expert opinions from all here on this thread, with special mention for Phil 213Cobra, has really piqued my interest in a whole new world of Zu loveliness, so I'm going ahead.
This really MUST be my last speaker purchase, so please Sean and everyone at Zu, don't tempt me a few years down the line with Def5s etc., I'll have to hope my hearing will have gone by then!
>>...so please Sean and everyone at Zu, don't tempt me a few years down the line with Def5s etc....<<

There's ALWAYS something next. You just have to know when the train has traveled far enough for you.

Phil