Triodes and Tetrodes and SET, Oh My!

[Mike Lavigne]

Does anyone have experience driving a big Genesis 1 Series midrange/tweeter panel with a medium or high power SET amplifier?

Ron, you heard Audiocrack's big Genesis with the Audio Note amplifiers?

not sure they are SET's but I'm sure they are wonderful amps.

 

[bonzo75]

Do you like the Verity speakers? I find them to sound generally not quite right. Only once I liked the Parsifals driven by the Nagra 845 monos.

The Leonores are good for cones for small rooms. You can voice them with amps. Not in Apogee/Acoustat league, but better than some other cones and smaller horns (which I don't like)

 

[bonzo75]

Again, I don't really agree. People said the same thing about big Acoustats (my Spectra 4400s were taller than a Fullrange and about as wide as one on the top). I actually had the Spectra 4400s running as subs and the Spectra 2200s running above 100Hz for a while and that worked amazing in a 20 square meter room.

Sorry, completely disagree. I haven't heard your big acoustats, but I heard FRs and Grands in big rooms and Grands in a small room. There has to be room to feel the bass waves and to get the benefit of the height, which comes together only at a certain distance from the speaker. I would totally agree with Lissnr where he sold off his Divas in 18*13 room and went with a Duetta instead. Sounds lovely.

 

[morricab]

Sorry, completely disagree. I haven't heard your big acoustats, but I heard FRs and Grands in big rooms and Grands in a small room. There has to be room to feel the bass waves and to get the benefit of the height, which comes together only at a certain distance from the speaker. I would totally agree with Lissnr where he sold off his Divas in 18*13 room and went with a Duetta instead. Sounds lovely.

Feel the bass waves?? Please don't tell me you believe that a room has to be above a certain size or you can't get deep bass. I got some very deep, powerful and controlled bass from my IRS Betas and Spectra 4400s in my 20 square meter room. You could measure it and hear/feel it.

A Diva or Duetta Sig will work equally well in most rooms because radiation pattern is so similar. The Diva might even work better as it is closer to a true line source. That said, I have found the two-way Apogees sound more coherent overall and maybe the preference for the Duetta Sig had more to do with that than the fit in the room.

I heard big Fullranges in Holland twice and once in Germany and was not moved by a the sound either time despite in Germany having the excellent Sphinx Project 16 amps on the speakers. That was in a pretty large room.

 

[bonzo75]

That large room is a very narrow room and with a lyngdorf which you hate. Anyway, yes, I wouldn't recommend either in less than a 8m * 5m room, same goes for Amphitryon, maybe a bit smaller, and I wouldn't recommend a Diva unless one has over 20 feet length.

 

[bonzo75]

Lissnr had divas for a year in his room, and couldn't get them to work had to sell off. His duettas sound sounds awesome in that room.

The German distributor of Analysis has both the Amphitryon and the Omega in his room, and uses the Omega for his personal listening. You can swap them around, the first thing you will realize when you move the Niger brothers in is that you lose imaging, while the Omega will be much more cohesive. He will not recommend the Amphi unless the room is seriously large. And his is 6m long and 4.5 wide. The cost difference between the two models is 3k only, so it's not the price.

I have heard another Amphi in a 25 feet by 15 feet room, and though it sounds nice it could do with more room size, especially width.

Planars have to disappear to get maximum benefit of planars. And they don't when the planar is too big for the room.

Again, I am dedicating myself to an apogee project - it will start with a duetta, amp experiments, and then end up n with an FR a few years later only if I can manage a minimum 8m long lounge in central London, else end up with a Diva

 

[morricab]

Lissnr had divas for a year in his room, and couldn't get them to work had to sell off. His duettas sound sounds awesome in that room.

The German distributor of Analysis has both the Amphitryon and the Omega in his room, and uses the Omega for his personal listening. You can swap them around, the first thing you will realize when you move the Niger brothers in is that you lose imaging, while the Omega will be much more cohesive. He will not recommend the Amphi unless the room is seriously large. And his is 6m long and 4.5 wide. The cost difference between the two models is 3k only, so it's not the price.

I have heard another Amphi in a 25 feet by 15 feet room, and though it sounds nice it could do with more room size, especially width.

Planars have to disappear to get maximum benefit of planars. And they don't when the planar is too big for the room.

Again, I am dedicating myself to an apogee project - it will start with a duetta, amp experiments, and then end up n with an FR a few years later only if I can manage a minimum 8m long lounge in central London, else end up with a Diva

Maybe the Omega simply sounds better for other reasons.

Have you owned any large planar speakers? Or just heard them at other people's places?

 

[bonzo75]

Maybe the Omega simply sounds better for other reasons.

Have you owned any large planar speakers? Or just heard them at other people's places?

There is not much difference in Omega and Amphi except the size. I am giving you experiences of the German distributor who along with the US distro has been the longest distributor of the Analysis.

I owned the Summits - more of an hybrid than a planar, and had the Omegas in my room for audition.

That said, listening to multiple speakers in multiple rooms, and piggybacking on another's experience curve always adds more to the learning than referring to our own systems experiences.

Also, if Lissnr says the Diva did not work in his 18*13 room, I would listen.

It might also be that you listen more to chamber, I listen more to orchestral.

 

[Ron Resnick]

Ron, you heard Audiocrack's big Genesis with the Audio Note amplifiers?

not sure they are SET's but I'm sure they are wonderful amps.

Yes, and I loved the combination!

 

[morricab]

There is not much difference in Omega and Amphi except the size. I am giving you experiences of the German distributor who along with the US distro has been the longest distributor of the Analysis.

I owned the Summits - more of an hybrid than a planar, and had the Omegas in my room for audition.

That said, listening to multiple speakers in multiple rooms, and piggybacking on another's experience curve always adds more to the learning than referring to our own systems experiences.

Also, if Lissnr says the Diva did not work in his 18*13 room, I would listen.

It might also be that you listen more to chamber, I listen more to orchestral.

Well, actually I listen to orchestral quite a bit, perhaps not as much as chamber but plenty I would say. I am particularly fond of violin and piano concertos rather than actual symphonies...although I like those too.

As for planars, not only have I owned several, my friends have had many many planars. I personally have had the following: AudioStatic ES100, Infiinty IRS Beta, STAX ELS F-81, Apogee Caliper Signature, Acoustat 1+1, Acoustat Spectra 2200, DIY planar hybrid with BG driver and Acoustat Spectra 4400. My friends have had the following: Acoustat Spectra 22, Acoustat 1+1, Apogee Studio Grand, Apogee Stage, Apogee Diva, Apogee Scintilla, Apogee Fullrange, Apogee Grand, Apogee Centaur Major, Quad ESL-57, Magnepan 2.5r, Magnepan 1.6QR, Magnepan 3.6, VMPS 30 (planar hybrid), Relco Sinus One, Final 1.4 reference. I have heard them with all kinds of amps: hybrids, SS, PP tubes and SET.

I have heard them in large and small rooms. Divas in large and smallish rooms. They worked fine in a smallish room. Acoustat Spectras work great in small rooms, as do the Apogees I have heard. In big rooms it is more hit and miss because there is actually far more room interaction as you typically sit further away and there is greater delay in the reflections. The nature of dipole means that you have nulls at the sides of the speakers and this minimizes the first reflection interaction with the side walls. If it is a tall line source then you have much less interaction with the floor and ceiling as well because there is very little dispersion vertically.

I had my planars always a little bit over 1 meter from the front wall but they could be very close to the side walls without having a significant impact on imaging and soundstaging. I got fantastic imaging and soundstaging with my Acoustats even though one was only 10 cm from a side wall and the other was open to and L-shaped part of the room. Shouldn't work, right? But without that first reflection the imaging didn't get skewed. Ask Christoph about how it sounded. It is the main reason he has Acoustat Spectra 22s (same as 2200 just cosmetics) and KR VA350 upstairs. You do have to toe the speakers slightly and maybe people are having issues that can be solved with how they set up the speakers.

With my horns, I have them in a room that is small and in theory shouldn't work well...but I have toed them in radically to minimize the side wall reflections and the imaging is very good. When I had them straight ahead it didn't work well at all.

 

[morricab]

Yes, and I loved the combination!

With the Martin Logans, the impedance of the panel is potentially a big issue with some amps. It seems they drop to about 2 ohms above 10Khz or so and this might make some tube amps sound rolled off in the highs.

 

[bonzo75]

Planars can work well good to the side wall. My reason for width was more that they should be apart, and then have the corresponding length for the triangle, not that they cannot be close to the side wall.

Close to the side wall reinforces bass. A bit of space allows the soundstage to feed back. I have often praised Christoph's Acoustat set up on this forum. That, and Lissnr's Duettas, which (I consider 18*13 to be a small room), are excellent.

Yet I maintain that for Amphi, FR, Grands, you need a massive room. Ditto for Trios with bass horns, Animas (Animas do extremely well wide, like at Munich) and such horns, which are the ones I like anyway. And yes horns are best in a corner, to minimize side wall reflections, to make max use of the space and in the case of Animas, bass reinforced. The Anima designer and the UK distro prefer them straight on, given a good room, I agree, but in a smaller room would toe them in, though I wouldn't advocate them for less 4.5m wide.

I have heard many other Duettas, a Scintilla, Christoph's and Flo stuff as well. I was always a fan of horns and modded Analysis over Apogees. I went Apogee mad after listening to Henk's and Rich Murry's stuff.

 

[KeithR]

Jadis are very different from KR and NAT. The latter two are more neutral, transparent. My experience is more with NATs which are more powerful and dynamic and high on SS qualities of separation, bass, without giving up tone. KR is great too.

I normally don't like coloured valves like AN and Kondo (the extremely expensive Kondo is good). But Jadis is one of the pretty sounding things I love. It is like opening a window and letting the sun in - but lovely, involving. On paper, it has negatives compared to NAT, it is muddier and slower, but if you like it it could become your top choice. Someone told me it distorts a lot and the distortions make it sound more natural. Possible. Also the range is from 30w to 500w.

Thanks - we seem to think alike here. I heard the simple I35 and it was indeed like a light streaming through a window, but quite beguiling. Jadis uses excellent transformers, no negative feedback, conservative power ratings etc. I didn't feel the new model was as classic golden, lush sound as I expected and feared. I always enjoy KR demos at shows and will hear them again in a few weeks. I suspect the KR is more like my Dartzeel though with its SS input stage.

I have found NAT sounding dark at the shows, but haven't had one in my system.

All three have more popularity in Europe, of course.

 

[bonzo75]

Thanks - we seem to think alike here. I heard the simple I35 and it was indeed like a light streaming through a window, but quite beguiling. Jadis uses excellent transformers, no negative feedback, conservative power ratings etc. I didn't feel the new model was as classic golden, lush sound as I expected and feared. I always enjoy KR demos at shows and will hear them again in a few weeks. I suspect the KR is more like my Dartzeel though with its SS input stage.

I have found NAT sounding dark at the shows, but haven't had one in my system.

All three have more popularity in Europe, of course.

NAT is darker than Jadis. Jadis is not necessary lush, just very involving inn s different way.

 

[morricab]

NAT is darker than Jadis. Jadis is not necessary lush, just very involving inn s different way.

the big Jadis amps are supposed to be rather dark sounding I heard. The NATs I have heard (and I have heard many) I would not consider to sound dark. They are not even overly warm but slightly warmish. KR is less warm but perhaps even more tonally correct. I heard the Jadis Defy 7 MKIII with special silver cabling that was tonally very good and overall not too far away from the KR Audio VA350i on a pair of Focal Maestro Utopias. I left pretty impressed with the Jadis after that demo given how good I think the KR is. I would really love to hear a pair of NAT monos on my Odeons to see how they compare to the Diana but that is unlikely to happen.

Interestingly, I have seen that NAT has a new "Single" integrated that uses the GM70 tube instead of the 805 and it is now in two boxes. Also, they have a new SE1 that uses again the 211 but is a hybrid in the same manner as KR Audio (input and driver are SS and big output tube). That might get a sound closer to KR but the dealer told me it is still more "tubey" sounding than KR.

 

[Ron Resnick]

the big Jadis amps are supposed to be rather dark sounding I heard. The NATs I have heard (and I have heard many) I would not consider to sound dark. They are not even overly warm but slightly warmish. KR is less warm but perhaps even more tonally correct.

. . .

Dear morricab,

The KR is less warm than which? Less warm than the Jadis or less warm than NAT?

(I would assume KR is less warm than both Jadis and NAT.)

 

[microstrip]

the big Jadis amps are supposed to be rather dark sounding I heard. The NATs I have heard (and I have heard many) I would not consider to sound dark. They are not even overly warm but slightly warmish. KR is less warm but perhaps even more tonally correct. I heard the Jadis Defy 7 MKIII with special silver cabling that was tonally very good and overall not too far away from the KR Audio VA350i on a pair of Focal Maestro Utopias. I left pretty impressed with the Jadis after that demo given how good I think the KR is. I would really love to hear a pair of NAT monos on my Odeons to see how they compare to the Diana but that is unlikely to happen.

Interestingly, I have seen that NAT has a new "Single" integrated that uses the GM70 tube instead of the 805 and it is now in two boxes. Also, they have a new SE1 that uses again the 211 but is a hybrid in the same manner as KR Audio (input and driver are SS and big output tube). That might get a sound closer to KR but the dealer told me it is still more "tubey" sounding than KR.

IMHO we can not separate the Jadis sound from their preamplifiers. I have now a JPL + Defy7 mkIII in my room, and have owned the great JP80 + the JA80's power amplifiers. The JLP is a very dynamic and alive preamplifier, an excellent example of positive tube coloration and matches the Defy7 perfectly. The JP80 was much more refined, with delicate but great dynamics, and less colored. It was a great match with several SS amplifiers. Unfortunately I never tried the JP80 with the Defy7. The JA80 sounded lush, nice sounding, but lacked dynamics in my system. Probably with more efficient speakers my opinion would be different.

BTW, do you have any details about the silver cabling that was used in the Defy III?

 

[Ron Resnick]

Thanks to each of you for contributing to this thread!

I, for one, have learned from this thread a lot about a lot of amplifiers -- without actually hearing anything new myself. (Of course we have to listen for ourselves. But, I believe that when you understand someone’s sonic preferences, and you have calibrated your preferences to their preferences on equipment you both have heard, then it is possible to triangulate meaningfully on, and understand, what they mean what they discuss components you have not heard.)

I have had my VTL MB-750s for something like 18 years and I intend to keep them forever. I know well that Luke and Bea and many owners of Siegfried IIs consider the older generations of big VTLs dated sonically. For my purposes and preferences I do not necessarily agree.

I am sure the new generation of VTLs, with bigger and better power supplies and transformers and capacitors, exhibit flatter frequency response and better control over woofers and more extended high frequencies. But I like a bit of high frequency softness and roll-off. In any event it never occurred to me that I would ever consider a different amplifier.

Then I began auditioning ribbon-based panel speakers (Genesis, Gryphon Pendragon, re-built Apogees). And then I began listening to horn speakers driven by SET amplifiers. I now understand the attractions of SET amplifiers.

So I wanted to investigate whether I might prefer the sound of the midrange and treble frequencies of a ribbon-based speaker driven by a high-power SET amplifier to the sound produced by my VTLs in triode mode.

The NAT amplifiers obviously are beloved by many Europeans who have heard them or own them. From numerous reports the KR amplifiers, too, are extremely highly regarded. The NATs and the KRs seem to represent a close and fascinating contrast.

On the one hand I like that the NAT Transmitter and Magma are all-tube designs. On the other hand I like that KR manufactures their own triode tubes designed specifically for audio, rather than pressing NOS transmitter tubes into audio service as NAT does.

From the posts on this thread I believe there is a reasonable consensus that the KR -- with its “reverse hybrid” transistor input and driver stages -- exhibits slightly tighter grip in the low frequencies, and may have overall slightly greater “slam” and dynamics, among other desirable characteristics, compared to the all-tube NAT. But there also seems to be a consensus here that the NAT will sound a smidegeon warmer than the KR.

My application of an SET amplifier to power only the midrange and tweeter drivers of a ribbon panel speaker would mitigate the low-frequency advantage of the KR over the NAT. Plus, purely philosophically, if I can stay with an all-tube design then that is my preference.

So who says audiophiles cannot agree on anything? I think there is a statistically significant consensus on this thread that all-tube NAT is a bit warmer than the KR SET which may be a bit warmer than VTL push-pull in triode mode which (according to Michael Fremer) is a bit warmer than the big darTZeel. So there is some agreement on at least part of a tight spectrum of amplifiers at a very high level of sound quality and equipment which straddles the tube/solid-state sonic line.

Since I would be looking for a new amp to power only the midrange and treble drivers of ribbon speakers above 100 hz (Genesis) or 200 hz (Gryphon Pendragon) the low frequency advantage of the KR over the NAT would not help me in my particular application.

If I were to try any new amplifier for this specific purpose it would be the NAT Magma New.

PS1: Where exactly Jadis amplifiers fall in this group of amplifiers remains a mystery to me. But since I would want to try an SET I would focus on NAT and not on the push-pull Jadis.

PS2: If we were to expand this tight, high-power, SET-based discussion beyond NAT and KR to include Lamm and Ypsilon and Aesthetix Atlas, I fear any consensus about sonics would collapse quickly!

 

[bonzo75]

Hi I doubt you can say KR holds an advantage over magma (or transmitter) on bass without comparing.

 

[Ron Resnick]

Fair enough -- I do not know. But that question is moot in the particular application (above low frequencies) I have been thinking about here.

PS: I wrote I feel that we may have achieved some consensus -- not unanimity.