Zu Druid & Definition Roundup


In separate threads about the Zu Druid V and Zu Definition 3 & 4 in this forum, several questions have been directed to me about the comparative merits of these models, supertweeter capacitors, and a variety of other variables. Rather than bury comments in those threads, I thought it better to start a new thread and focus any follow-up comments or questions in one place.

Over the past few weeks, I helped a new Definition 3 owner install and setup his speakers, after earlier having setup his loaner Def3s that had an earlier iteration of the supertweeter network. Additionally, I made a capacitor change on the high pass filter to the supertweeter on my own Definition 4 and Druid V speakers. For further perspective on this, I have lived with my Definition 4 speakers for the past 13 months, and my Druid Vs for the past three months. Prior to that, I have migrated through the Definition 1.5 > 2 > 4 upgrade path, and Druid “3.5” > 4 > 4-08 > 5 upgrade path in two discrete systems since 2005. Any search on Zu topics or my handle here will serve up plenty of commentary on Zu speakers, cables, suitable amplification and other related matters, so I am not going to attempt to repeat all of that here. But I am going to roll up a collection of observations in response to prior questions, that might help Zu owners understand the relative value of current options in the upper half of Zu’s range, as well as people who have never owned Zu but who are considering their speakers, to better grasp what they might gain.

Druid 3, 4, 5

My first Druids were a used purchase from a prior owner here in Los Angeles. It turns out they were one of the first 10 pairs of Druids made. They had been sent back to Zu in late 2004 to be upgraded to then-current configuration plus had full internal Ibis cabling. The first 10 Druids made had the Speakon connector for full B3 geometry from amp to drivers when using Zu cables (I did), along with parallel Cardas posts for connecting any other cable. When I bought this first pair of Druids, they were shipped to me from Zu, in what Sean called a configuration he approximated as “version 3.5.” That speaker hooked me on the holistic Zu sound, but it had a euphonic warmth and soft top end that was forgiving and not fully revealing. Nevertheless, that v3.5 Druid was addictive for its unity of behaviors, and much like the original Quad electrostatic its ample advantages made it easy to overlook its limitations. The v4 upgrade opened up the top end marginally and was welcome, but the Spring 2008 v4-08 upgrade to Druid was a big leap toward bringing Druid closer to the liveliness and open top end of Definition. Then Druid was taken out of the Zu line. I let the Essence aberration pass by. Sean got back on track sonically with Superfly but I preferred the Druid form factor so stuck with the dead-ended Druid 4-08 for my secondary system, all the time lobbying Zu – along with other Druid owners – to restore Druid in more modern form in their line.

We got exactly that in Druid V late last year. For 4-1/2 years, while Essence came and went, Superfly got the HO FRD and then Nano, Druid was static and falling behind. Version 4-08 still had some tone-density and focus that was sacrificed in Superfly in favor of that speaker’s livelier, burstier dynamics and somewhat more expansive scalar projection. Superfly also had a slightly more extended top end than Druid 4-08 so to most people it simply sounded more like a modern speaker should, than Druid 4-08. It also had a more complete Griewe implementation, for faster and more textured bass than Druid. Druid V addressed all that, and more. The more advanced multi-composite cabinet with integral full Griewe and the mechanical grounding of the thick aluminum plinth would have comprehensively improved Druid even if the old Druid drivers had been installed. But the advance of the Nano FRD and the Radian 850 in supertweeter use gave us a Druid form factor speaker that has the linearity and finesse of Definition, with the traditional focus, unity and tone density of Druid even more present and obvious than in any prior version. Druid V *is* the modern equivalent to the original Quad ESL, without the extreme beaming, the bass limitation, dynamic restriction and fragility. It just happens to deliver Quad-like unity and speed from dynamic drivers with much higher efficiency *and* power handling. Druid V is finally an uncompromised and uncompromising speaker that despite its price can be justifiably driven by the very highest quality amplification at many times the cost of the speaker, yet can put modest amps in their best light. Why would anyone drive Druid V with amplification that costs lots more than a pair of the speakers? Because the total design can leverage stellar amplification, and no other speaker today can duplicate the full combination of attributes that Druid V delivers. You can get even greater focus and unity, ironically, in Zu’s line from the ~$60,000 Dominance, with its radiused front baffle and three FRDs, but not with Druid’s lightness of mass, presence and drivability. No Magico at any price can deliver Druid’s pure unity of behaviors regardless of what you try to drive them with, and no Magico is as musically satisfying with such a wide range of amplifiers. Druid V laughs at the cacophonous disunity of a Wilson speaker. Druid V ridicules the dynamic choke points imposed on Focal speakers at the crossover points. In the same way that no one appreciative of the unity of the Quad ESL heard any musical value from the Infinity IRS or a Duntech Sovereign back in the day, a Druid V owner today can pretty much ignore the rest of the alleged “high-end” speaker market inflicting damage upon our hearing, with the exception of other Zu speakers.

Because of the newest Nano FRD’s ability to reproduce more musical scale than prior Druids, for the first time in version V, Druid is a credible HT2.0 speaker in addition to being a great 2ch music speaker. Also for the first time, Druid is now quite good for listening to a full orchestra, whereas earlier Druids fell short on scale for orchestral purposes. Druid V is the first “no-apologies” Druid. That’s not to say that Definition doesn’t have advantages for more money – it certainly does. But Druid V is now a true all-music, all-purpose speaker with no real musical limitations in practical domestic use, and if a lower linear limit of about 35Hz isn’t deep enough for you, there’s always Zu’s new subwoofers. It’s also extremely amplifier-friendly. And the Griewe implementation does a fabulous job of extracting solid, tuneful bass from low-damping-factor/rising-deep-bass-THD SET amplifiers. Druid V gets qualitatively better bass from 2a3, 45 and 300B SET amps than any unassisted (no powered sub) speaker I can think of.

Definition 1.5, 2, 3, 4

The 2004/5 era Definition 1.5 was a revelation in its day, for its combination of speed, transparency, resolution, scale, bombast and finesse while having very good unity behaviors and terrific amplifier friendliness. It was sharply different from the same-era Druid because of its extended top end, almost tilted a little bright, and for its impressive sub-bass foundation. It was a relatively big, bursty, lively speaker even driven by modest power. It also had two clear deficiencies: first the sub-bass array amp had no level control (later and quickly rectified for everyone after I pointed out the glaring omission upon receiving my speakers), and second, that v1.X Definition’s MDF cabinet “talked” at high SPLs, marring the clean and incisive sound with an overriding glare. In Definition 2, cabinet talk was dramatically reduced by introduction of the birch-ply cabinet structure, stronger baffle, more robust plinth and associated damping techniques. The voicing of the speaker also tilted somewhat darker but the net result was a Definition absent ringing and glare, cleaner at moderate SPLs and far less fatiguing at high playing volumes – even fair to say altogether unfatiguing. While Definition 4 introduced many simultaneous improvements, Definition 3 shows clearly how much cabinet talk was left in Def2’s “silent” cabinet. Def3 starts with a Def2 cabinet and gets additional bracing and damping during the upgrade and it is plainly apparent when you first fire up Def3s after being familiar with Def2, that sound emerges from cleaner, quieter noise plane in the newer speaker. Def3, while retaining Def2’s 4x10” sub-bass line array on a rear baffle, gains seriously-improved deep bass by virtue of replacement of the Def2 plate amp and level control with Def4’s D amp with parametric controls. The Dominance trickle-down Nano FRD gives Def3 a close facsimile of Def4 performance from lowest response up to 10kHz or so, but Def3 uses the older-generation Zu supertweeter, which cannot begin to match the beauty, finesse and spray of the Radian 850 supertweeter used in the upper range Zu speakers. Def3 sub-bass performance is not equal to Def4’s but it is surprisingly competitive. In the Zu FRD range of roughly 38Hz – 12kHz, Def3 is very close to Def4, separated by clear differences in cabinet construction and internal configuration that give Def4 advantage as should be the case. As you get above roughly 8kHz, where the Radian 850 in Def4 begins to slope in, the upper range of the FRD in Def4 through the Radian’s exclusive extension on the top are in absolutely every way contributive to an elevated sense of musical fidelity and realism.

Definition 3 would be a market-wrangling speaker not surpassed at 3 or 4X its price if Definition 4 did not exist. But it does. As good as the new sub-bass amp and parametric controls are for the older 4x10” line array on the back baffle of Def3, the 4x10” rear-firing cones can’t load the room as evenly and deliver the incisive unity of Def4’s downfiring 12” driver. As closely as Def3’s Nano FRDs match the same in Def4, the completely re-architected cabinet of Def4 allows the drivers to perform with greater neutrality and freedom from distracting resonance. And the Radian 850 sprays the loveliest and yet most objective harmonic content of any tweeter I can think of today. The combined effect of Def4’s improvements over the Def2/3 design make it a compelling upgrade worth every penny to anyone who can afford its price compared to Def3, and yet the bargain roots of rendering Def3s from donor Def2s yields a speaker that is astonishingly great for its sub-$10K price and is necessarily limited in the number that will be produced. Notwithstanding that Omen Def is probably the peak value point in a two-FRD Zu speaker, for true high-end applications, Def3 is the high-discretionary-income value point and Def4 above it is the luxury alternative that nevertheless has no non-essential waste in its composition or price.

Definition 3 or Druid V?

I get this question privately from time to time: “For less than $2K difference, Druid V or Def3?”

These two speakers suit different priorities. Ask yourself the following:

1/ What is your application? That is, do you use your speakers strictly for 2-ch music or is your system doing dual duty for 2ch music and HT2.0?
2/ How important is the bass region between 16Hz - 35Hz to you?
3/ What are you using for amplification?
4/ What is the size of the space you have to acoustically load, and how far you sit from your speakers.
5/ What are your music listening habits, and what are the 3 - 5 sonic attributes you most value to feel satisfied?

There’s not a straightforward answer to this question, without knowing the above, but it’s easy enough for anyone reading this to self-sort. Druid V will give you focus, tone density, top end finesse and beauty that Def3 can’t quite match; Def3 will give you spatial & dynamic scale, deep bass foundation, resolution and horizontal dispersion that Druid V can’t equal. Overlapping both are the speed, agility, transparency and shove of the Zu Nano FRD. So, having the honest self-awareness to know what satisfies you most if your finances force a choice, will yield a crisp answer. If you can’t live with the trade-off, that’s your signal to save, and save, for Definition 4s.

Supertweeter Network Capacitors

Recently, there has been a lot of new interest in capacitor upgrades for the supertweeter high pass filter in Zu speakers, particularly the Druid and Definition. I have not been able to listen to all the available and oft-discussed options. My Def2s and Druid Mk 4-08s had Mundorf Silver-in-Oil caps. I had my Definition 4s built with V-Cap CuTF as an upgrade over the Mundorf. My Druid Vs were built with Mundorf Silver-in-Oil. In January, at Sean Casey’s recommendation, I had Clarity caps installed in both Def4s and Druid Vs. My Duelund capacitors are back-ordered (well, Zu urgently needed my pair for a more demanding customer), so I await them. I have heard Duelunds in non-Zu speakers. There are a few things I can say about capacitors at this stage, with more comments to follow as I put more contenders head-to-head.

1/ Every capacitor brand, formulation and composition brings specific attributes and a sonic signature. None are perfect. Not even Duelunds. You tend to think that what is best in current experience is as good as it gets until you hear something better. I can understand why someone feels ecstatic allegiance to Duelund caps, while at the same time appreciating why someone else prefers V-Cap TFTF or CuTF or some other alternative to them. For example, Sean Casey takes the position that Clarity caps bring 85% of Duelund’s sound quality to Definition 4 and Druid 5, for less than 1/3rd the retail cost. Elsewhere on this forum, another poster relates a conversation wherein Sean said something similar about the Audyn True Copper caps (90% for 10%). I haven’t heard the Audyn capacitors so have no comment right now. I will say that if Clarity is close to Duelund results, then both are a clear improvement over Mundorf Silver-in-Oil. The Clarity cap is both revealing and exceedingly smooth. But the case for Clarity (and by extension Duelund if Sean’s assessment holds) isn’t a slam-dunk compared to V-Cap CuTF or TFTF. There’s such a thing as too-smooth. This is reminiscent of the same disagreement I have with advocates of “slow” voiced SET amplifiers compared to the quick and transparent Audion SET amps that are so unlike most other SET brands. Some listeners are strongly attracted to a too-smooth representation. A lot of instruments have some harshness and rough texture in their output. The Clarity sands a touch of this off, just like (but less than) the round-sound old-school SET amp voicings some listeners favor. The V-Cap has more snap & tooth in its sound, but it is also less forgiving. I’m still in trial with a decision about whether to stick with Clarity or return to V-Cap CuTF or TFTF – as well as Duelund – pending. No, don’t bother assuring me that I’m going to love Duelund caps. Just consider me open to being convinced, but also not assuming a priori I will be.

2/ All of these exotic film caps take time to settle in. Clarity sounds great fresh but then they put you through a few weeks of meandering performance. They seem to be sensitive to temperature during the infant hours of use. We’ve had an unusually cold December and January here in Los Angeles, and I don’t use much furnace heat (you northerners and east coasters should see what people in SoCal consider a “furnace…”). A day of 64 degrees in my house sets breaking-in Clarity caps back a couple of steps. A warm day with internal temps in the high 70s pushes them forward. Then they go through a period of sounding beautiful on simple music, but shut down with congestion and blur on complex music. And then they start being reborn again to reassert their original convincing impression, and more. You have to be patient with any change.

3/ The Radian 850 in supertweeter application in Druid V and above in Zu’s line is intrinsically smooth, articulate, detailed and lovely. Frankly every cap sounds great into it, with the worst and the best still within the realm of excellent. You’ll hear differences and likely develop clear preferences, but even the basic Mundorf Silver-in-Oil sounds fully credible and completely acceptable in the absence of hearing something better. But the advantage of upgrading the Clarity (or Audyn True Copper, I imagine) is unmistakably beneficial to Def3’s supertweeter, and any earlier Definition or other Zu speaker using it, is fairly dramatic insofar as you are paying attention to top end harmonic character and are influenced by it. Clarity really tames much of the comparative roughness in the pre-Radian Zu supertweeter, compared to all the stock cap choices put in those speakers. What I’m saying is, pick your cap for Def4 and Druid5, knock yourself out. Some will sound definitely better but all will sound very fine. But if you have a Zu speaker using the older supertweeter and have an appetite to give them a worthwhile refinement, get a Clarity cap network upgrade. The cost is very reasonable and the benefit is disproportionately large at the price.

4/ There may be a cheap sleeper in capacitors. I was discussing film cap upgrades with Bob Hovland a couple of weeks ago. He mentioned that his more recent research indicated that the material consistency of the dielectric in film capacitors (even thickness & density, absence of pinholes) is more influential to sound quality than specific materials themselves. He wasn’t suggesting that all more exotic capacitors might not deliver someone’s preferred sound, but he does believe an excellent sounding cap can be made from prosaic materials. SuperCaps has a relatively new family of “Robert Hovland Edition” film caps that are highly affordable. They are handmade in the US, comprised of non-exotic materials, highly inspected during build and sealed tightly. I got some samples from Bob to try in my tube-output DACs and the results exceeded my expectations by a wide margin. They are more than good enough to settle on, and are staying in the DAC (mhdt Havana Balanced). He is next very eager for me to try a pair of 1uF/1000v versions in my Zu high-pass networks. I don’t know what to expect relative to Mundorf, Clarity, Audyn, Duelund but it’s a trial too interesting to not undertake. I’ll post back results, perhaps after I can put Duelunds in the mix, too.

Enough for now. I’m happy to add comments if questions are posted. I am sure I will remember something I intended to write here, but forgot.

Phil
213cobra
Keithr,
Congratulations, I've read good things about this german company. Based on it's design and simple circuit approach it would seem better than the Mac for a purer and natural sound. Listening will sort out the answer.
Regards,
I'm itching for those babies and the Zuboys have been great. The Chinese New Year, plus things I'll never know (or really care to know) are slowing down the Radian delivery, so they say. I should have well over 1k of hours on my Defs, so that is the upside. Christian terminated (looking back, much too early) my Ibis for the 4s, but since it was taking so long the 16 guage HOME DEPOT lamp cord was not doing it for me, Christian/Gerrit sent me a pair of Events to hold me over. I like them very much. My Ibis are 10 feet long, and rethinking things, given the new speaker layout in my crib (much better) I'm going to ask them to shorten the Ibis by 5 feet and remove those metal jammies near the spades which do nothing. I'm trying as M Scott Peck said in The Road Less Traveled, "to delay gratification," but this is ridiculous....lol...you've given me a little kick in the ass to call Christian and see what's the buzz. I'll let you know. "love 'em more tha ever?" What's going on now, that was not going on before?
Positive Feedback's Def IV review....painful piece of writing. I was cringing, reading this horror, though [still] excited about the Defs. So much copy that said so little. Lots of "wows" about the bass, though. The Defs deserve a cogent, meaningful piece of writing in an audio pub that packs some wollop. This must have been his first review? No editor over there? Phil could (and did, thank god) do this review in his sleep.

Spoke to Gerrit. Some of the tweeters have made their [little by slowly] way to the coast/Utah. They want the 4s to fly outta Utah more than (well almost) I do. Soon!
I agree about the Positive-Feedback review of the Def 4s. Hard to read and did not say much of substance. While probably less widely read, the Audio Beat review was much better.

http://www.theaudiobeat.com/equipment/zu_definition_iv.htm

Of course, no one surpasses Phil's commentary on Zu products.
Gsm, you might be interested to know, but the pair reviewed in the Audio Beat review are the ones proudly sitting in my apartment now. So glad that Roy Gregory liked them. Agreed with 99% of his comments, but parted company where he describes a hint of harmonic leaness. In fact the one thing I believe the Def4s could never be accused of, is this attribute. Zu's tone density remains supreme, full tone but not at the expense of dynamics/agility.
A beautiful pair. And I agree with you. Zu Def4s cannot be accused of being lean.
The ability to customize the finish including "silver" vs black trim is outstanding. My pair are piano black with silver trim. I have seen others in a medium gray (or natural wood) with black trim.
Is there a problem with the A'gon spkr section? A thread for Polk fom earlier in month seems to be locked/frozen at top of listing.
Two months and no Def IVs. Tweeters China, whatever. May bag my order and wait until the Fall. Warm weather coming. Not the listening season for me. And I always have my 1.5s to keep me company. Knowing Zu, by the time the Fall rolls around the Def Vs will be in the works. They probably are already.
That's a big shame, Warrenh. I wonder if all potential customers are having a protracted wait?
Christian emailed me late yesterday and said he believe that they will go out at the end of the week. We'll see.
Warrenh, it's not like you to sound so sanguine. You're normally one of the most enthusiastic contributors here. I have to say my dealings with Sean, Christian et al have always been friendly and business like, so maybe give them the benefit of the doubt. I hope you get your wish soon.
Spirit, I do, I do....they are the coolest and I have expressed that to them. In fact here is a sentence from my last email: "Christian don't rush it, I wouldn't want a loose wire..lol" I'm good, but frustrated. Knowing what's coming is enough. The wait on my new car has been more than twice as long...
Warrenh, your new car can wait. It can only take you from A to B on the road; the Def4s will take you to a whole new destination. I've just had a pro classical musician (violinist) listen to my system, and he LOVED the tone of the sound produced, rating it very close to the real thing. Got to love those FRDs with no pesky XOver to spoil the show!
Your Def1.5s are no slouches, so the wait should be as painless as poss.
Remember, "Good things come to those who wait".
frustration does not equal pain. I thought I was clear on that. I'm burnt listening and talking about the 4s. It will happen; and until then?----all will hear, when I hear.
Anyway, the car is a man's thing, Spirit, as you know. 8 naturally aspirated cylinders, 6.3L roar...I get tingly all over. Oops this isn't the Car and Driver. thread...life is good :)
Warren, having just become the proud papa of a used pair of Def IV's, I can easily say that you will be very well rewarded for your patience:).
Congratuations. Wow, that'a good get; used IVs this early in their audio life. good for you. It will be soon. I'm cool. enjoy your new babies...
I'm totally jealous, Morgan! I should have alld off my seldomly used analog rig and jumped on it myself! Lol.

Congrats and keep me posted.
Thanks for the support Guys! It helps to feed the addiction:-).

In general, I have learned the following in the last few weeks after
1. Visiting Phil's amazing set-up in LA and experiencing his amazing hospitality not once, but twice!
2. Arriving home and receiving my new Def IV's and setting them up and hearing
A. the immediate improvement vs the Def III's.
B. the obvious weaknesses compared to Phil's reference system.

First off, the new Radian tweeter is even better than advertised. It is crystal clear with no fatiguing at all even at really high volumes ( thanks Phil:)) with an amazing holographic soundstage projection. This tweeter will no doubt be a big boost to Zu's success in the future.

Secondly, I realized that when I had the Def III's I was no were near hearing their full potential. I know this because the Def IV's in my system are no where near as good as they were in Phil's system.

I believe that this lack of hearing their full potential is, as Phil has stated many times, due to my amplifier's under performance. I am using a 6 watt PX-25 and I believe it is just running out of gas and lacking in headroom to properly power these beautiful speakers. So now I am on the path to reaching a very lofty goal, and that is realizing this speaker's full potential.........
Something doesn`t seem right here. with a 101 db(very high sensitivity) 16 ohm speaker( easy load), 6 watts is a lot of power. Consider at reasonable listening levels of 75-85 db you aren`t even using a 1/2 watt of power(more likely 1/10-1/5 watt range)so there`s should be surplus power on hand for musical peaks.

There are people using single digit power amps with this speaker who have no problems.Not sure if this is a question of power quality or quantity. This speaker should be extremely easy to drive if its specifications are right.

I have no doubt this amp responses to more power like phil`s 845 SET but if should sing with 6 quality watts also.
Regards,
Definition 4 is an 8 ohms load speaker. Yes, you can drive it easily with 2, 4, 6w but that doesn't mean you will get the full dynamic life that's both convincing and possible from more power. It's not a "problem" running small wattage from an efficiency and loudness level, but you are not going to get all the drive and shove that a Zu speaker is capable of with small output triodes. "Singing" and showing the truer burstiness of real music dynamics are not the same thing. I started out with 8/8w on Zu back in 2004. I've also heard them with 1200w McIntosh mono amps, where the advantage was that a lot of sound could be derived from the first couple of Class A watts, but the unlimited headroom brings clarity that tiny amps don't deliver. It's not an average SPL level, it's energetic clarity. On a 6w amp in a sizable room, you're going to hear the dynamic limits of the amp, even on a 101db/w/m speaker. Remember, that's 101db/w/m -- as in @ 1 meter distance. No one is listening at 1m.

This power requirements thing is an easy thing to pencil out and convince yourself that a handful of watts will be fine. It can be beautiful. But when you compare it with the drive and shove of a big glass triode @ 20-25w, the effortlessness and clarity of nano-duration peaks at satisfying levels makes it hard to return to flea power. You end up with the experience Morgan has articulated. For Definitions or any of the Zu dual-FRD speakers specifically, the synergy between Zu + 845 SET is breathtaking for the twin deliveries of musically convincing shove and tone.

I have to point out that a Sonus Faber's 90+db/w/m efficiency argues for the sufficiency of a 50/50w amp, but that in fact sounds woefully inadequate after you've heard their speakers on equal-clarity high power. This is consistently true for other 90db/w/m speakers too. The trick is finding equal-clarity high power. Zu's extra 11db of efficiency means you can get that and it's effects at 25w SET.

Phil
Charles1dad,
I had the PX25 myself with both the Def 3, & now the Def 4 and can verify that the amp ran out of steam at concert level volumes (with rock type music anyway). I would say my room is sort of on the large side with vaulted ceilings. Maybe this makes a difference, I don't know.
When I say the amp ran out of steam, I am referring to distortion causing short listening sessions because I was being overcome by fatigue.

PS- not sure it makes much difference but I believe the Definitions are an 8 ohm load.
Charles, "6 quality watts" as you say, regardless of 101 db, is just plain ole; not enough. Of course, this depends on what I am listening to, but in general, even in trio jazz, where one may need Stanley Clarke's electric Fender bender bass to shake it up a bit; 6 watts is just not going to do it. Me? mostly jazz, but that is mostly, 6 watts will do it most of the time. On the other side of mostly is where more than 6 watts lives. 35 SET watts is almost more than enough for the/this Woodstock baby. On the other side of "almost more than enough" is everything from The Who to Metallica and back again. I have been living with 101db and 35 SET wpc a happy customer. I do, however, have a plethora of tunes that (given my Zu Def 1.5s) I would love to (though my tympanics couldn't handle it for too long) bring to an spl level to bring back the old days and remove some of my wife's clustrophic nicnacks from the shelf. Time has been the test and I will not make the change to make that temporary spl rush happen, but I would love to hear what my Def's could do at that level. I hope this catharsis of claptrap made some sense.
I understand your point, that`s why the 101 db sensitivity spec may perhaps be a bit optimistic. In the context of true 101db range,6 watts is quite a bit of power,remember you`re only using 'fractions' of a watt under most conditions.I`m not doubting your results, afterall you hear what you hear in your own systems.My point is that true 101 db/1 watt/1 meter is exceptionally sensitive.That`s horn territory.Could possibly be the DEF is more 95-97 db sensitive(which is still high compared to most speakers).
Regards,
Hi Morganc. I'm running my Def4s from a Hovland tube pre/SS pow combination, and am v. happy with the results, although I am tempted to at least audition SET power, viz. Audion Black Shadow, that Phil recommends.
Can you be a bit more specific as to what his system excels at, and how it synergises with the Def4s?
While I haven't heard the PX-25, I have used the following amps with the Zu Definitions Mk1.9: Melody M300B, Atma-Sphere M60's, Clayton M200's, Sophia 845 mono's with 205 driver tube, and Cary 805AE. The Melody and Cary sounded dull and lacking in power. The Sophia sounded decent, but not as powerful as the Atma-Sphere's. The Clayton M200's were very nice, but totally overkill and not quite as nuanced as the Atma-Sphere's.

On my Definitions Mk4 in the same ~6,000 ft^3 room, I've used Atma-Sphere M60's and Coincident Frankensteins Mk2 (actually purchased from MorganC just a few weeks ago). The Franks sound every bit as powerful, probably more so, than the Sophia 845 mono's. I base this on common comparisons with my long term reference, the Atma-Sphere M60's. In terms of bass weight, bass texture, and dynamics, the 8 watt Frankensteins are simply better than the 26 watt, 845 based Sophia's and really close to the Atma-Sphere's, possibly better in some cases. In general, I much prefer the Franks to the Sophia's. I will be keeping them long term along with the Atma-Sphere's.

I could imagine running "out of steam" with the Franks on REALLY demanding material at house party levels, but I rarely play that loud even for a single song. With the Atma-Sphere's playing what I consider loud, it would peg the meter for a millisecond on big climaxes, but usually only pop up quarter to half scale. This would be in the neighborhood of 95 - 98 db peaks on a RadioShack SPL meter, c-weighted. Full scale on the Atma-Sphere in the DC offset measuring position I run it in, is 1 watt. That leaves about 9db of headroom for the Franks at similar volume, confirming why I don't sense strain when listening at pretty loud levels. What kind of volume are you guys jamming at when you sense strain?
Germanboxer`s experience is the type of example I was trying to explain, I also use the Coincident Frankenstein SET. I`ve compared it to a higher power Atma-Sphere in the same system. Both were fast,very clear and transparent,the Franks fuller in tone and body,the Atma-Sphere had a leaner character. Dynamics and drive as well as bass were very very close,the Franks a bit more dynamic, tactile/palpable.System and taste would determine choice(Germanboxers likes both).

I used a 60 watt push-pull class AB 6550/KT 88 triode amp prior to the Franks. In my system the sense oF drive and'shove' remain very close and the PP bass had a little more impact/weight(the SET fine texture,tone and articulation) but otherwise the SET is more natural,tonaliy correct and simply more realistic.

We all have are own standards for what we consider loud(I`m sure this is a factor) and not all amps at a stated power rating perform the same(power supply, caps,transformer quality all come into play).I probably don`t listen as loud as some here do.

Phil I get your point,no one sits a meter from their speakers. However a rating of 101 db if accurate suggests very little power is required to bring this speaker alive and kicking. I`m not for a momement questioning your Audion 845` performance(I really like a good 845 amp and could easily live with one) but Germanboxer`s comparison of the Sophia 845 vs his Frankenstein is another perspective that`s just as valid.

Obviously all 845 amps as well as 300b amps aren`t created equal and a hierarchy exists. My whole point is simply high sensitivity/efficiency should matter or why built them in the first place.I find these type of speakers better sounding in general and I don`t care for many of the lower efficiency "modern High End" speakers these days.It`s clear from this thread a variety of amplifiers can work sucessfully with these speakers.
Regards,
Keithr,
I`d be interested in your impression of the Valvet amplifier driving your DEF IVs(very well would be my guess).Curious to know how they contrast to the Quad tube amps you enjoy.
Regards,
I was thinking the same thing just moments ago, Charles. Interested in Keithr's listening impressions of the Valvet.
I've heard the Frankensteins and the Sophia 845 mono amps on my systems. I cannot reconcile Germanboxer's assessment that Sophia 845 dynamics were inferior to the Frank's, 26w v 8w, with my own experience. I can agree that the Franks yield better "bass weight, bass texture" than the Sophia because, well, the Frankenstein 300B amps are simply higher resolution that the Sophia. There is a key point in my earlier post: equal clarity in a higher power amp yields different impressions than higher power of inferior clarity. The Franks clip gracefully and deliver more information than the Sophia 845. Trying to get the same clarity from the 845 by playing it louder won't do anything other than magnify its deficiencies. But I'll also say that it was easy for me to hear the Franks run out of headroom in an unbounded 2240 cu ft space that feeds into a similar virtual volume as GB. In fact, aside from the Frank having good design and execution, good ratio of power supply to power output, there is nothing else exceptional about it physically. it sounds great, but it doesn't sound any more powerful than a pair of Audion 8w 300B SETamps with physically smaller power supply, I heard at the same time.

But this really isn't about Sophia vs Coincident. You don't have to be listening at levels of aural violence to hear the dynamic limits of an amp on anyone's 101db/w/m speaker. Yes, you can get quite a lot of sound out of 6 watts from a single PX25 tube driving a 101db/w/m speaker but that's in terms of SPL, not the same as achieving dynamic clarity and shove.

There are many things that affect this. One is perceived speed, transparency and the burstiness of one amp vs another on the same speaker -- the apparent instantaneousness that a sound emerges from blackness or silence. Another is how precise or sloppy is this event? Is it slow to start; is the initial defining impulse dulled; does the aftermath linger beyond natural expectations?

Yesterday I listened to a pair of Melody M845 monoblocks and to my Audion Black Shadow 845 amps on Def4s at some length, again. The Melody amps cost less than half the price of the Audions, so there is no criticism in what I am about to say. There is a rated diffence of 2-3w between the two amps, with the Melody having the slightly lower measure of output. In all ways the Melody M845 is remarkable and energetic, and a few good tube upgrades put it in another sonic league from stock. It would be easy for a listener to claim more bass weight from the Melody, but the Audions sound more powerful because they are more resolving and maintain their resolution to higher SPLs. The Audions are "faster." Sounds burst from the Audions with more finesse and projections. Morgan heard this as well, a week ago. But then I put a WWII production 6sn7 input tube Melody and the Shuguang 845C. The 845C is a metal plate variant of the 845 and Shuguang's example has lower plate dissipation, so you give up about 20% of a normal 845's power in a given circuit. That took the M845 down to about 16-17w. However, with the better input tube and the metal plate 845s, the M845 got a lot closer to Audion resolution, blackness and clarity and it wasn't surprising to me that one result was the amp sounds more powerful than it does with the higher output potential of the 845A, though it in fact has less in 845C configuration.

The Sophia 845 monoblocks are built around a more complex circuit than Audion's and somewhat more than Melody's. In my view the new ones carry this too far and I recommend them much less. The older Sophia however is highly sensitive to tube choices and can sound anywhere from just fine to excellent, for their prevailing price on the used market. But it doesn't have the resolution of the very competent Frankenstein.

I don't have to listen at high SPLs to sense an amp's dynamic restrictions. And it's not "strain" we're sensing and what Morgan was referring to. It's the clarity of unbridled transients and the overall sense of ease. In digital filtering there is the phenomenon of pre-ringing, wherein the evidence of a distortion is apparent before the cause. It's like hearing the resonance of a bell before it's struck. It's not really happening that way, but we experience the distortion as though it is. Not directly, but by analogy the dynamic ease of an amp/speaker/room combination is a way of sensing an amp's available headroom before the music exceeds it. The same is true of playing an acoustic guitar. You can play softly and pretty well anticipate how that guitar is going to respond to a massive input. I don't have to thrash an acoustic guitar to reliably know how compressed it will become on hard pick attacks. I can feel and hear its limits before I test them.

The PX25 is also sonically the leanest of modest power triodes. It's very clear but shove isn't among it's assets. Morgan gets 101db from the1st watt. He gets 104db from the 2nd. He gets 107db from the 4th. And then on the way to 110db he instead hears clipping. Now he's not sitting 1m from his speakers and he has a room to load with all kinds of soft and hard stuff in it to swallow acoustic energy. So is it so hard see how he would experience one amp that clips around 109db differently from one that clips around 115db? And even then, the drive and shove of my 845 amps exceeds the "experiential power" of my *same-rated* PSET 300B monoblocks.

I don't listen to "Highway 61" any louder with Zu speakers at 101db/w/m efficiency today than I did with Large Advents in 1974, but I do it with 1/6th the power and more clarity. When I started with Zu on 8w of 300B power I could achieve the same SPL on "Desolation Row" but not the same dynamic ease. Once you hear it, there's no mistaking a dynamically inadequate amp for a sufficient one. There are beautiful sounding 2w 45 amps that produce lovely sound through Zu Definitions. And if that floats you, fine. The common knock on big glass triodes by the SET aficionados is that they lack the finesse of the flea bottles. Well, to a point. But it's a lot less true today than when clumsy big bottle SET amps returned to the market in the 90s. And more to the point, the admirable finesse of flea glass triodes has its own lack: shove and ease. Things start to change when you get into 106db, 114db horns but then you have to deal with their anomalies. 101db/w/m is great in the context of more than two generations of 82db speakers but Zu gave us 101db speakers along with the resolution, speed and clarity to show you why dynamic ease is just as valuable as tone, resolution and finesse.

Phil
Good points Phil,
This is why I said there`s a hierarchy among amps within a given genre.The laws of physics prevail, a high quality 845 amp will have more"shove" than a similiar quality 300b amp. If execution is lacking then a lower power 300b amp(well design/executed) can be more convincing than an 845 amp even in the area of perceived 845 advantage(dynamic drive).This would explain why Germanboxers heard what he did in his system.The lower power 300b should have superior resolution yet some are less resolute than some 845 amps(the high quality versions). So overlap of result vs expectation happens.Simpler circuits do seem to trump complex circuits in general.

The Frankenstein`s exception drive and control(for an 8 watt 300b SET) has much to do with the level of its power supply and transformers.
I`m sure the same is true for Gsm18439(gary)Ancient Audio 300b SET. His amp drives the DEF IV in a large and open space with results he`s happy with.I`d imagine drive and dynamics aren`t an issue.
Regards,
There is a key point in my earlier post: equal clarity in a higher power amp yields different impressions than higher power of inferior clarity. The Franks clip gracefully and deliver more information than the Sophia 845.
I believe this quote from Phil is an important qualification for better understanding. The Franks do clip gracefully and do deliver more information than my recollection of the Sophia 845. Perhaps calling the Franks "more powerful sounding" than the Sophia 845 was imprecise on my part. I often, and probabaly incorrectly, conflate bass weight and bass texture with power, at least if it's still conveyed at higher SPL's. I'll concede this point.

I will try to be perfectly clear to the extent that I am able. My overall sense, the gestalt if you will, is that: the Franks convey more information, including dynamic expression, relative to my reference the Atma-Sphere M60's on the Def Mk4's than the Sophia 845 mono's conveyed relative to the M60's on my Def Mk1.9's in the same room. Since I include micro and macro dynamics together in the statement above, I suppose careful comparison could reveal the Sophia to be more macrodynamically capable, or "bursty", than the Franks. Neither were as "bursty" as the Atma-Sphere's.

I will add two observations from my listening session yesterday afternoon in which I switched the M60's back in to confirm some observations. 1.) On dynamic orchestral music, something I rarely listen to, I did note a greater difference in the size of the recorded space relative to the M60's than I recall with the Sophia's, relative to the M60's. I suppose this could be an example of running out of steam? 2.) On Terry Evans "Come to the River", on track 4, "River", played at really loud volume, I thought I heard hard clipping on his voice in several places. Through the M60's, moments later, it sounded nearly identical and was clearly an artifact of recording, possibly overdriving the microphone diaphram?
Atmasphere M60s are, let's face it, 60w push-pull, OTL monoblocks. Sophia 845s push out about 25w SET. the Frankenstein, 8w SET. All three being mono amps give you a dedicated and robust power supply for each channel. The OTLs are clean, assertive amps delivering more than twice the power of the Sophia, which in turn delivers about 3X the power of the Frank. So if Germanboxer's dynamic reference for evaluating dynamic traits in amps is his Atmasphere M60 pair, the issue comes down to which SET more closely approaches them for dynamic traits that are credible for music purposes.

I can imagine the information resolution of the Frank and its low frequency reach being preferable to the Sophia at a given SPL. It's not a preference I would attribute to the smaller amp somehow having "bigger watts" but certainly accept it can make a bigger impression. If a listener's perception of power is disproportionately influenced by perception of bass weight, however, I'd also have to point out that if in the Sophia the stock 845A tube was replaced by the 845B, that alone might completely change the perception because the B tube substantially alters that amp's apparent bass traits, favorably for someone predisposed to valuing bass weight.

The comparative judgment is complicated by having judged (and remembered) the 845 amp's dynamic traits against the larger OTL on Def 1.9 and then more recently rubbing the 300B against the OTL on Def4. While the rated efficiency of Def 4 and Def 1.X are the same (101db/w/m), the power transfer traits are somewhat different with advantage decidedly going to the Def4. Sean Casey has said that Def4 has power transfer characteristics of a 104db speaker. Plus the nano FRD has a lighter, stiffer, quicker cone shoved around by a much beefier motor. Def4 sounds more efficient and certainly sounds more dynamic and burstier on a given input signal than earlier Defs. The Franks through Def4s today will sound about 2-3db more powerful than they would have on Def1.9s.

Further complicating this comparison is that both the whizzer and the Radian 850 supertweeter are cleaner, clearer, smoother on the top end. With the same push, Def4 holds things together better and is absent the fatigue factors that lingered in the then-relatively-fatigue-free Def 1 & 2. Plus the more perfect cabinet of Def4 eliminates the "talk" of Def1's encased-mdf cab as well as the damped compression of Def2's dreadnought ply box. If the little amp wasn't evaluated on both, I posit that junior is now getting a lot of help from the Def4 itself!

On GB's last point, reduction of the apparent scale of sound staging is a non-tonal cue that you are overdriving (or nearly so) an amp in stereo pairs. In guitar amps where way-beyond-hifi-clipping is routinely and intentionally employed, this happens in the extreme where you can hear the mono speaker literally begin to sound smaller as distortion runs amok. A Marshall stack compensates for this, though:).

I don't have any argument with Germanboxer's preference for Coincident and Atmasphere. He has been listening to *three* amps that the majority of audio buyers would envy if they heard them. If 8w Frankensteins deployed as a stereo pair meet or exceed his expectations for convincing musicality, which includes dynamic credibility, then that's all that matters because those are sonically excellent amplifiers for Defs. If however he ever has a chance to hear a big-glass amp that delivers similar resolution with more shove, my guess is the point will be made. It costs much more, however, to get Frank-level resolution from an 845 circuit and that's the downside.

Phil
Phil,
Your last paragraph is a very good summary of the inevitable trade offs that confront us.The Franks are as you point out, high resolution.Their purity,transparency and fleshed out tone is what holds my attention,music just sounds real through them.

I can except that your Audion 845 or other high level 845 amps will have the better dynanmic drive and shove yet also render a high level of resolution. So while both amps are capable of exceptional dynamic drive and resolution, they trade places in ranking of these desirable traits. One is left with preference and sonic priority as the determing factor.Your positive comments on the Franks are based on actually listening to them. I`d love to hear the Audion Black Shadow 845 one day.I`m sure they would impress me very much and sould great with the Coincident speakers.I always appreciate your comments in this forum.
Regards,
Also, there are two generations of Sophia 845 amps. There are examples of each for sale on Audiogon. I would be curious if anyone has heard both.
Good points all around. I tried my best to clarify my opinions and the context from which they were formed. Rarely, are we so lucky as to have all combinations of gear available at the same time and in the same room. Equally rarely I would say are we so disciplined that we can control for all variables and properly assign those things we hear to universally accepted (and understood) language. If you pause to seriously consider, it's a wonder that "truth" can emerge out of the random trials and tribulations of geographically separated audiophiles at all. Yet, I believe it does...eventually.

If a listener's perception of power is disproportionately influenced by perception of bass weight, however, I'd also have to point out that if in the Sophia the stock 845A tube was replaced by the 845B, that alone might completely change the perception because the B tube substantially alters that amp's apparent bass traits, favorably for someone predisposed to valuing bass weight.

I don't overvalue bass weight, though I have (probably incorrectly) used it, along with bass texture at higher SPL's, as a proxy for the phrase "powerful sounding". Fair point on the 845B tube. I explored this option with Richard from Sophia on the phone; his response was to say don't change tubes. This amp is only tuned for the tubes that came with it. This, along with the inability to adjust bias without opening the chassis, ultimately drove me to return them.

I don't have any argument with Germanboxer's preference for Coincident and Atmasphere. He has been listening to *three* amps that the majority of audio buyers would envy if they heard them. If 8w Frankensteins deployed as a stereo pair meet or exceed his expectations for convincing musicality, which includes dynamic credibility, then that's all that matters because those are sonically excellent amplifiers for Defs.

"Dynamic credibility" is a good choice of phrase in this instance since I tend to evaluate amps much more on the whole before choosing how to communicate and assign attributes. If it's dynamically convincing, I spend far less time trying to parse how much more or less it is to another piece of equipment. I'm not a reviewer, but I don't mind attempting to add substance to this forum where I feel can.

If however he ever has a chance to hear a big-glass amp that delivers similar resolution with more shove, my guess is the point will be made. It costs much more, however, to get Frank-level resolution from an 845 circuit and that's the downside.

I would love to hear a big-glass amp that delivers similar resolution. If that is a pair of Audion Black Shadows, will the current stock Black Shadows meet this standard or are silver wound secondary's and signal path required? Are there other 845 or 211 amps that deliver resolution, tone and shove?

Oh, and one correction...I incorrectly stated that the Sophia amp I demo'd was a 205 driven 845 amp; it was actually the 206 Princess driven 845 amp...looked identical to the one on the 'Gon right now.

Jordan
I have heard the Sophia 845 amps multiple times over the last decade of their development. The first-gen chassis version was available in two configurations: the less expensive one using a 6sn7 as the driver tube, and the premium version using the 205D and later 206 power triode in the same role. The new version is built in a much larger, more robust all-aluminum chassis using the 206 driver.

The 6sn7 driver Sophia 845 was neither impressive nor seriously deficient. The list price was $6,000/pr. They were pleasant enough but the 6sn7 is barely up to the task that was assigned to it. The amps had triode glow and beauty, but lacked all the dynamic shove an 845 is known for. At the time, with far fewer 845 amps choices on the market, at their price they were fine for people who liked them.

The then-$10,000/pair 206-driver version of the Sophia 845 was much better; a truly convincing amplifier musically. I said for several years that if you wanted an 845 amp and couldn't afford the Audion Black Shadow, a used pair of Sophia 206-driver 845s were the next best thing. Once the new chassis amps were introduced, trade-ins of earlier Sophias made them regularly available for $3500 - $4500/pr. Those amps are highly responsive to tube upgrades, and are energetic and musical. They don't have all the finesse, expansive spatial dimensioning and the same agility as the more expensive Audions but they strike you as a very nicely balanced design. They are not more dynamic than they are articulate. They don't have stronger bass than they do top end. They are not more resolving than they are dynamic. Midrange is unmistakably by way of SET. These amps can sound dull or bright or correct, depending on the tubes mix. They do a good job on Definitions; they do a great job on leveraging the burstiness of Soul Superfly while leavening some of that speakers aggression.

The new generation Sophia 845, now $20,000/pair, disappoints me. The designer favors a needlessly complex circuit. To his credit, he has given the new amp a large power supply. But the amp sounds like a promising design pushed a few steps too far. It's essentially a scale-up of the older 206-driver version and the fine balance of factors present in the older amp has been lost, in my view.

I heard these amps twice, both in another person's room on Zu and in my own home. The new amp is a high resolution 845 but it is relentlessly aggressive. It's tonally and dynamically forward to a fault. There is more aggression than finesse, which causes the amp's very fine ability to present nuance to be masked by its steroid overkill. I imagine that some of Sophia's customers who listen through less efficient, crossover-intensive speakers may like this. The aggression of the new Sophia 845 punches through the fog of passive crossovers and multiple drivers' disunity behaviors. But what it punches through with is musclebound & overstated. Through wideband, crossoverless and ultra-responsive Zu, the new Sophia enlarges (and enrages) every note it hurls. Even chamber music played quietly comes to sound a little angry. Through the new Sophia, every musician is in a bad mood. OK, authentic for Glenn Gould even if overdone here, but the Sophia makes even Arthur Rubinstein sound snarly! The amp's emotional tilt is dark. The tonal tilt is bright and in your face. Bass is very strong -- more impact & slam than from the Audion Black Shadow.

In the same period that Sophia's 206 driver 845 amp has increased from $10,000/pr to $20,000/pr, the Audion Black Shadow has increased from $11,000/pr to $13,500/pr. The Audion has only gotten better in all the ways it was already good, preserving its balance along the way. It's a simpler circuit and it has proven anvil reliable. It outclasses the new Sophia in every manner except for sheer bass slam where the Audion is not slouching. So whereas the Sophia 845 was once the more plentiful (in the US) and affordable alternative, it is now more disturbing to hear, less nuanced and less balanced for more money. Some people will like the Sophia's aggression but it has lost its place on my recommended list. The Melody M845, *retubed from the stock glass,* is now the next best 845 to Audion, in current production at a lower price.

Phil
>>...I explored this option with Richard from Sophia on the phone; his response was to say don't change tubes. This amp is only tuned for the tubes that came with it. This, along with the inability to adjust bias without opening the chassis, ultimately drove me to return them....<<

Richard always says that. It's nonsense. The 845A and 845B have the same bias requirement. In fact, after guiding a local friend into old chassis Sophia 845s we staged a listening comparison between the A, B & C tubes. The B was best and that's what he ran with. Some time later he had a power supply capacitor give up and the amps were taken to Bob Hovland for inspection and repair. I made a point of asking Bob to check the bias and other operating parameters in the amp with the A & B tube and change any that needed to be optimized for the B. Everything was the same for both tubes, and what he found was that the factory bias was not spot on for either A or B. What Richard means when he says the amp is only tuned for the tubes shipped in it is that he *voiced* the amp to his preferences and he wants you to buy any new tubes from him.

Further, most 845 SET amps do not have "fixed bias" (ironically meaning adjustable bias), so that's no reason to turn down an SET 845. They are set up for the RCA spec and will work with any tube that conforms. Otherwise a tech simply has to make a resistor change.

>>If that is a pair of Audion Black Shadows, will the current stock Black Shadows meet this standard or are silver wound secondary's and signal path required? Are there other 845 or 211 amps that deliver resolution, tone and shove?<<

The current production Audion Black Shadows meet the standards of sound I describe. Mine have copper xformers, but all silver signal path wiring. Until recently, that's the only way Black Shadow was made. Now Audion allows you to order it in "Levels" just like the Golden Dream, wherein one of the variables is how much silver do you want to pay for in the xformers -- including power. My Golden Dreams have silver secondary windings and I have no doubt that silver in the xformers of Black Shadows will yield the same advantages. But it's not necessary to have silver there to get an outstanding amp. But if you do, yours will be better than mine, no doubt!

Having just spent a few weeks with the Melody M845, I think they have real potential, particularly if biased for a metal plate 854C or a KR 845 (along with filament feed changes if needed). I also think there is a lot of leverage in that amp in going with a very high quality 2a3 driver tube, like a KR or EML. It has shove, very good tone and while it falls somewhat short of Audion's resolution & speed, it's quite credible, for less cash. The M845 isn't as finely balanced in traits as the Audion, but it's less than half the price. It comes closest to equaling the Audion on shove (owing to its large power supply), is a step behind on tone, a couple steps further back on sheer resolution (but still very good), and falls somewhat further behind on speed and transparency, where I think ultra premium tubes can narrow that gap.

The push-pull 845 Nagra amps have lots of energy and very high resolution, with their depression on the polar curve being in tone. Then there are a proliferating plethora of 845s coming out of China for as little as $1500 up through the Shuguang premium amps and I haven't kept track of all of them.

Phil
The evolution of the Sophia 845 is regrettably another example of added complexity in a circuit resulting in poorer performance. Why can't designers resist this path and recognize that simpler is better.Simple well executed circuits result in better music reproduction, tone, dynamic nuance, inner details and naturalness. They will ultimately provide deeper emotional involvement convey more realistic presentation.

It seems from Phil's experiences the Sophia 845 is more hifi but has lost some musical soul and communication. Perhaps it's more impressive from an engineering stand point but fails where it matters most.Are simple circuits harder to implement successfully?
Regards,
Phil, I see that both Sean and Christian of Zu have their Audion Black Shadow SETs for sale via Ebay, Zu moving over to SIT power amps. What are your thoughts on this, it seems strange timing that BOTH of them would be passing along their Audions?
Spirit,
There`re a number of people moving from SET amps to the First Watt SIT amplifiers.Certainly the SIT amps may do some specific things better.I believe the higher level SETs retain particular sonic advantages that the SIT is unable to match.Phil and Keithr alluded to this in earlier insightful posts.It becomes a matter of what attributes are most valuable and cherished.I haven`t heard a SIT but given the impressions of Phil and Keith I supect I`d likely prefer my current amp(just a hunch).All amplifiers have some degree of compromise.You choose what combination of strength and weakness you prefer to live with.
Regards,
Phil - you mentioned in an earlier post of the 6SN7 driven Sophia 845 not having enough drive or something to this effect and that the 6SN7 was not up to the task. I'm totally clueless on this sort of thing, but it looks like the Black Shadows use a 6DJ8 for a driver? I would have guessed that the 6SN7 had more drive potential than the 6DJ8, though admittedly I have nothing other than size of tube to base this on. Any thoughts on driver tubes for 845 based SET's? Thanks.
Jordan
I had some preamp fun recently and compared my Valvet Soulshine8 to the Melody 2688 flagship on Zu Def4s. The Melody definitely had larger, more refined sound with better dynamics. Very nice sounding with the Audion Black Shadows--although I think the pairing was a hair too warm for my taste (and the 845B is the likely culprit) after I returned to my Valvet/Quad system at home. I think the Melody's huge power supply probably adds to the success story here.

I believe the Melody preamp is 8k list (Hugh can confirm), so quite a good value in today's flagship preamplifier market. I would note that I am buying a quad of NOS 6sn7s for the Valvet which should bridge the gap a bit closer--they are using Full Music tubes currently.

I also had a listen to the Druid Vs- I think they are a brighter speaker (i have to wonder if 2 FRDs balance out the Radian better) and would sound best with tubes and vinyl (and did). I still much prefer the soundstage of the Defs, but can see why folks who value immediacy would prefer the Vs. I still think Superflys in a vinyl-only system will be my second system of choice some day.
>>...both Sean and Christian of Zu have their Audion Black Shadow SETs for sale via Ebay...<<

I'm only aware of one pair of Audion Black Shadows up at Zu, and just Sean's personal pair for sale on eBay. As noted in the eBay listing, the driver here, first and foremost, is that Sean's attention has been grabbed by the Allnic DHT preamp, which he has to pay for, along with the SIT-1s he needs to use the preamp with. Even at industry accommodation pricing it's expensive. And his enjoyment of that preamp depends upon using it with SIT-1s. As Sean has expressed to me, the Allnic DHT line stage is "just a good preamp, probably no better than Melodys and maybe not as good, with a good tube amp like the Audions..." and that the SIT-1s "...have all the traits and deficiencies described when used with a normal preamp...." but that together each becomes something special. Sean will have SET amps again, but with the Black Shadows the Allnic DHT isn't worth its cost compared to other options that work beautifully with the Audions. The electrical match between the DHT pre and the SIT-1s (which, remember, are also single-ended, just single-ended silicon) renders both pieces able to perform beyond their intrinsic sonics alone.

Now, I haven't heard the combination yet. If not before, I will when Sean comes to LA for the Newport show. Srajan has put himself on record there's exceptional sound from these two items used together. Sean Casey agrees and so does one of his customers. But Sean also concedes that the DHT doesn't lift the dynamic limit I notice in the SIT-1s. And I don't know whether the DHT pre somehow addresses the unnatural note decay in the SIT-1. I don't know how sensitive Sean is to that in his evaluation.

>>What are your thoughts on this...?<<

My thoughts on this are that they're Sean's amps and he can do whatever he wants with them.

Keep in mind: Sean is a speaker and cable designer and manufacturer. This gives him access to hifi gear at prices not attainable by most of us here. He's saying that $10,000/pr SIT-1s are only worth owning if you drive them with a $20,000 DHT preamp. Even if I find I like this combination, I can't buy them new for the prices he can. What if I found that in some ways this $30,000 combination of pre + monoblock amps is better than my then-$11,000 power amps with my $7,000 Melody P2688 preamp? Would it make my Audions and Melody sound any worse? Of course not.

But for me, since a DHT preamp can't address the SIT-1's dynamic constriction and clipping characteristics, I'm not a buyer at any price. And if the Allnic DHT preamp is "just a good preamp" without the SIT-1s, well, then, it too is interesting only as an abstraction for being a quaint circuit revived.

I'll see what I agree with, or not, when I hear them together.

Phil