Atma-Sphere M60 or David Berning ZH270?


Hi, I need some helps to decide which one of these two amplifiers to go with my 14ohm Coincident Super Eclipse (SE).

The Atma-Sphere seems a perfect match for the SE at least in impedance matching and at 14ohm, may get more power than 60 watts. The ZH270 may get less than 70 watts @14ohm. However, I have the following concerns for the M60:

1. 8 6AS7 output tubes per side generates a lot of heat and it does not have cage protection. This is quite a problem if you have young children at home like me. The ZH270 has tubes internal (like a Tube preamplifier) and thus safer for young children.

2. 16 6AS7, though last long time, can be more expensive than ZH270's 4 6JN6 if I try to replace them.

Pro for ZH270 can run without a preamp and is auto-biasing.

On the other hand, ZH270 is more expensive ($4995) than M60 MKII.2 ($4250) (current still have a few left).

As far as the most important factor: sound? I have no idea at all. I have not heard either one anywhere. I have owned ASL Hurricane for over a year and like the sound very much but disappointed for the constant re-biasing and QC problem.

Does any one have Reliability problem with either one?

My listening room is 13Wx8Hx26L and I listen almost only classical music from solo violin, piano, to chamber music to 20 century's big symphony orchestra works (Mahler, Strauss, Stravinsky, etc.).

Thanks for the helps.
laoyuap
i always believed janson caps to be the best caps you can,
buy except the ultra expense durland mega caps at over $1,000,
each???
This is a great thread! I'm also looking at the Berning vs. M60 choice for Coincident speakers. The high impedence of the Coincidents looks like a natural for the M60's, so I'm glad to hear some positive experiences there.

Another choice that has just come on my radar screen is Bruce Rosenblit's new OTL design, the Transcendent Sounds BEAST, only available as a kit for about $3700.

I'm a OTL believer, altho I've got a few transformer tube amps around too. Right now, in my upstairs system, I'm using the Transcendent T8 OTL with a pair of North Creek Eska speakers, with an impedence "twister" that keeps them around 7.8 ohms, plus/minus 2. These make very nice music, especially believeable on small-scale chamber music, male vocalists and ensemble groups/folk music.

When my Coincidents arrive, I expect they'll be much more efficient, but I'm still looking to upgrade to a higher-power OTL, and I hear the M60 calling my name. So thanks for all who shared perspectives on this thread! Happy ears!
Thank you for your observations Laoyuap, I'm glad you are happy with the synergy and the sound. I find my Atma-Sphere and Coincident combo to be very much as you described your setup with the Berning in terms of the musicality. Cheers!
Hi, fellas:

I apologize for answering this thread late due to busy and laziness. Here are my impressions of the amplifier and Coincident SE:

I think they are very good synergy at least in my environment. I donÂ’t have much experience with varieties of amplifiers to try, but so far I have been very impressed with the sound of this combination.

The Berning ZH-270 seems to possess strength from both world of solid state and tube amplifier without their weakness. To me, it seems to remove a veil between the sources and your ears. ItÂ’s clean and clear as those good solid state amps do yet retains the harmonic richness of a tube amp. It makes musical instruments more life-like and less artificial. The high frequencies are clean and smooth and the lows are ample without exaggeration. Listen to the opening movement of the symphony no 7 by Mahler (Tennsted/LPO/Angel LP). The sound of the tenor horn has body and weight yet rich and smooth and the sound clearly comes from right and rear corner of the orchestra. The mid are rich and smooth too as demonstrated on violin/fortepiano by Luca/Bilson playing the MozartÂ’s violin sonatas (Nonsuch LP). You can clearly hear the musicians breathing of beginning of a phrase as in Mozart B-flat string quartet (Amadeus/DGG LP) or breathing between movements/CD tracks of a piano sonata (BrendelÂ’s Beethoven sonatas Philip CD). I can listen to ZH270 and Coincident SE for a long time without listening fatigue.

Again, I'm very impressed with these two combination.
R_f_sayles, I agree with you about the class A/B switch which I didn't have added for the same reason: would never use it, didn't see any point in adding the complexity (on which Ralph agrees, I believe). I suspect for a Silver Edition the big difference will come from the new regulator circuit for the driver power supply and the re-building of the output section (how the output tubes are wired) which lowers distortion levels even further plus enhances tube life.

Regards,
I'm with you Rushton in terms of artisans and upgrades in your closing note and thanks for the word on updates. I am certainly not interested in looking for something other than what I own but, was interested in hearing Laoyuap's observations considering he has the same speaker line as I. These amps leave me a very, very happy camper. Turns out my Atma's are in line for an update after the holidays as they were built just before serial #646. Because they are Silver Editions they already posses the Caddock resistors and Teflon coupling caps. Fortunately they do not have the class A/B switch (that I would never take advantage of) or the auto-bias (which I find to be just a luxury item). I look forward to the upgrade and plan on keeping the true OTL magic going on in my living room. Happy listening. Cheers!
Since this thread has been revived, I will offer that I've recently received back from Atma-Sphere my updated MA-2s bringing them to the most current factory spec. The improvements Ralph has rendered since the MkII.2 series was introduced are simply astonishing!

Since many of the changes in the circuits apply to all of the amps in the Atma-Sphere line, what I'm hearing in my system leads me to believe that any comparisons of earlier production runs of any of the Atma-Sphere amps (i.e., prior to the end of 2004) simply don't reflect the full capability of a current production Atma-Sphere amp. From what I've gleaned in talking with Ralph, more improvements were slipstreamed into production at the end of 2004. So, even if the amp has the current MkII.3 model designation or was updated to MkII.3 status, if the update was done prior to the end of 2004, there were still some significant improvements slipstreamed into production towards the end of 2004.

Those of you who have Atma-Sphere amps and have not yet made the most recent updates, you're in for a real treat if you do it. And for those of you who've listened to Atma-Sphere amps in the past, if you liked some of what you've heard, there's much more to like today. I'll post some further observations in another thread when I have the time to pull my thoughts together on this.

(Note to those who don't like manufacturers continually upgrading their designs: please consider that we are talking about "boutique" designers/crafts people at this level of the high end of the audio art. Ralph and others like him are highly creative individual artisans constantly seeking to improve what they are delivering to the public. For me, I'm pleased and grateful that they engage in this continual creative process.)
Laoyuap, It has been some time since your Berning ZH270 purchase and the start of this thread... well how is this compo of amps and Coincident Super Eclipse Speakers? My curiosity is due to the fact that I am running Atma-Sphere MA-1 MK2.3 Silver editions with Coincident Total Eclipse. I enjoy them immensely and have never heard the Berning amps to draw a reference. Cheers!
Laouap,
I have heard the Berning on Super SE's and you won't be dissapointed. I am running the Berning with Totals and am very pleased with the sound. Power and reliability are not a concern. At med feedback with volume at 12oclock I am in the 100db range. I am a previous M60II.2 owner and even though the Atma's are nice amps the Berning has more to offer in all the ways described in this thread. In my experiance the Berning is more powerful, reliable, much quieter, has better deeper bass, and sounds more live. I feel the Berning does 110% of what the M60's can do. The other nice thing about the Berning is it runs warm not hot. I can put my hand on top of the Berning and leave it there as apposed to actually burning myself on the output tubes of the Atma-sphere. In my opinion you made the right choice and you will be happy with it for many years.

Take care.
Laoyuap
Thanks, I'm looking forward to getting the Berning. Concerning the Joule, I haven't had a chance to audition it at home. But, I have heard it on several occasions at shows and it sounds wonderful. Music is reproduced accurately across the frequencies and the midrange is simply magical. I lack the vocabulary to describe all the the aspects of the amp, but coupled with the Merlins, it has a certain liveliness and presence that is spookily real.
The Joules are beautiful, eye candy, drool-inducing gears. They are also out of my price range, but after hearing and seeing them, I was willing to wait and save up. Come buying time, I began to call up the distributors and after numerous phone calls and discussions, realized that I simply don't have the space, patience, and time to take full advantage of the amp. That was when I began looking at other alternatives, and the Berning amp began shining like the holy grail over the horizon. After several exchanges with Bobby P., Allan Baghan, and Audiogon members, I ordered one. I have actually never heard the Berning, but there are people of whose opinions and experiences I have come to trust, and all the tell-tale signs point to the Berning.
I will be running it direct to an APL Denon 3910 (also on order.) I will post my impressions, but it will probably take several months for everything to break in (Between work and grad school, it's tough to find time.) Keep in touch, and congratulations! I would love to hear your impressions after you've gotten your Berning.
Bluebull,

Sure, I may write a paragraph or two for my initial impression after receiving the amp. Thanks for your input.

Mhu,

Congratulation and have fun for your new adventure. I've never thought about buying Joule Electra product simply because their OTL amps just too expensive for me. The price of Berning is already outside my initial budget limit. In fact I was initially looking for Atma-Sphere M60 in mid $3k and almost bought a pair but cancelled order because of my concerns listed above. Same reason (cost, heat and kids) for me not considering Israel's highly recommended Canary CA339 and DeHavilland GM 70 (both in $7k) though they may match my SE perfectly. I assume you have heard Joule with your Merlin at your home. If you do, how does it perform specifically in terms of music reproduction? The JouleÂ’s OTL do looks gorgeous in comparison to either AS or Berning. I think if I own a Joule, I may concentrate too much on "visual pleasure" and be distracted from listening music - the potential penalty one has to pay (just kidding...).

Please share your impression of your new amp after you get it.
Laoyuap,
I will be receiving my ZH270 sometime next week. I'm using the VSM-M and was torn between the Berning and Joule Electra. I pretty much bought the Berning for the more practical reasons everyone mentioned here. The Joules are huge, and sounds richer, but their sizes are impractical as I live in a condominium. Plus, for what it's worth, I like low key looking gears. Btw, I ordered mine with all the tweaks. Good luck and have fun with your Berning when you get it, I'm gleefully waiting for mine.
Laoyuap
Dont forget to let us know what you think when you get the Berning amp.Many eyes will be watching.....

Chris
1markr, Rushton, Artg, and Tubegroover:

Thanks. With your guys and so many others assurance, I am really looking forward to it (for sometime in March arrival). I hope I will be able to concentrate on the "music" instead of "sound" and "equipments".

Tubegroover:

I have added the internal silver wire upgrade already if this is what you are referring to. The Cryoed tubes and cap upgrade are included in the base price.

Thanks again.
Hi Laoyuap

When you get your amp and live with it for a while for an added treat I highly recommend the internal wire mod. As Oneproof notes, this is a remarkable improvement in effortlessness and ease. I have owned the amp 3 years as of yesterday. It is the one audio component I am certain I will never part with for reproduction of music, size, reliability, low heat, weight and its inconspicious visual appeal. It is up to anything you throw at it within its power rating always holding the music in correct proportion to the recording. Great choice and enjoy your amp!
Laoyup - well done! As i mentioned, bot hare excellent, but you will not regret your decision to get the Berning. Welcome to the club of the lucky few who have these amazing pieces.
And a good choice it is! You will really enjoy the amp, and you will see it's in a whole other league vs. the 'canes. I used to have the 'canes as well.
Hi, Gentlemen. Thanks a lot for your suggestions.

I have decided to try the Berning and enrolled me in Allan's waiting list. It seems both are good amplifiers. For my limitation, Berning is the only choice.
Laoyuap, yes, my Coincidents are modded. The mods are quite extensive.

The original Vifa tweeters were replaced by ScanSpeak Revelators that I got from Israel. The Seas midwoofers were completely rebuilt by the BEST speaker guy in the world - this mod is more significant than I can explain to you. Let's just say that naturalness, speed, and slam all jumped up several steps. The wiring was replaced. The cabinets were damped, but not overdamped, and stuffed. What was a very nice speaker came to realize its full potential.

And, OTL amps have always been rare. If Coincident wanted to keep going in that direction, nothing would have stopped them.
Just my 2-cent as an Atma-Sphere owner. Unfortunately I have no experience with the Berning amp.
I put a pair of M60 MK2.2 into my system this past July and in a matter of days decided to sell my Krell monoblocks that I have happily lived with for more than 10 years.
To my ears the AM is simply "truer" and "righter" than anything else I have listened to as far as timber accuracy and tonal balance go. It has none of the problems I've heard from other tube amps possibly in part due to AM's elimination of output transformer. Both extreme ends of audio spectrum are well extended and defined, sound stage and imaging is also as good as any I've heard. This all from pairing it with a pair of less than ideal speaker with a nominal 4-ohm impedance.
The reliability has not been an issue. It never missed a bit from day one.
There is also something to be said about the benefit of completly point-to-point wiring without the use of PCB. This also opens up the opportunity for future tweaking and upgrading if you are into the sort of things.
I like it so much that I am actually in a process of getting a pair of MA-1 Silver to better match my speakers.
Hope this helps! Best of luck and happy listening!
Laoyuap, here are the mods to the Bernings that I have: 1. All tubes replaced with NOS, some cryo'd, some not, not really a mod I guess, I think that new Bernings come with the Cryo'd 6jn6 tubes stock now, not sure

2. The ERS mods

3. Some of the caps have been replaced, again maybe that is stock now, not sure

4. The silver wire mod that Allan mentioned to you.

Also, since I have two 270's I run as monoblocks, I had some internal rewiring done to bridge them, but that's obviously not an issue with one amp.

I feel like I'm missing something, but I guess not.
I heard the Atmosphere and the Berning in the same system but not at the same time(A/B). In purely sonic terms, the Atmosphere edged out the Berning except in the bass. I thought the Berning had more PRAT. Otherwise, in all other matters--heat production,tube replacement,tube biasing,electricity bills,and especially compatibility with a wider range of speakers, the Berning wins hands down. Since I live in Florida, heat production was a crucial factor(I mean ALOT of heat). I ended up with the Berning and enjoyed it very much. If heat and speaker compatibility weren't major issues, I would have bought the Atmosphere amp. You won't go wrong with either amp. Enjoy listening.
Have had MA-2's for a period of about 4 years, and the reliability is not an issue at all.
tubes as used by AS are cheap, and the output tubes will last forever.
the game is to not go down below 4 ohms, i have made quite a few combinations with different speakers, and the power output of even the M-60 will drive anything (up to a few) loud enough.
the MA2's did find their waterloo hooked up to a pair of Genesis 501's which happen to be my new pair of speakers..
the impedance is around 1,7 Ohms in the region of 500 Hertz. that my friends is a knock out for any OTL amp.
although the combination still did manage to go loud, the soundstage and the lower mids are lost.
the combination sounded anorexia.
I eventually sold the MA-2's.

As for transparancy and a top end to die for, you cannot go wrong with AS amps.
If you look for warmth and lush sounds look elswhere.

Very recommended.
Thanks guys. Your advices really helps!!

Swampwalker writes:

"The best way to explain it in terms of your musical tastes (forgive me if I'm way off base, I said I'm no classical fan) is just different readings of the same score, or different character of 2 different, great old violins"

Very good analogy, indeed. As a violin player and 1/2 piano player (I am a amateur though I have attended local chamber ensemable), I know exactly how a violin (though not Stradivarius class) and piano should sound in my room. I can never reproduce the instruments sound in my room with my stereo system. The resonant quality of the sound of a violin just isn't there. I hear more like sound of hi-fi than a real instrument. But different makers of violin do make difference from my mi-fi system. The distinctive sweetness of "Amati" and pure transparancy of Stradivarius can be clearly identified. So Amati as Atma vs. Stradivarius as Bernings (no judgement here of quality just different sound, actually I like both instruments sound depending on what music is played). Regard to "different readings of the same score", are you refering to Bernstein vs. Karajan, Yo-Yo Ma vs. Rostropovich, or Janet Baker vs. Christa Ludwig? This sounds more like "interpretation" to me and after all, Hi Fi, in my opinion, is an art of reproduction not interpretation. But I like your analogy anyway.

Nealhood & Rushton:

What a nice photo! I like it a bit more than the current version of the M60 II.3 and actually I like their old chasis better than the new. The connectors and speaker post are still on the front that makes connection a bit awkward and WAF is low (at least my wife isn't thrill about it). The Atma's may sound fantastic but to me it looks more like a labs equipment than consumer product. In my humble opinion, their products really need a good industrial designer (like Pass Labs XA and X.5 series stuffs). From looking at the photos of Berning, it's also just plain looking as well. "Sound" is the utmost important priority but be sure you can look at it everyday and can live with for a long time.

Trelia writes:

"But, as Spencer pointed out, with my Coincidents, which are incidentally warmer and more full bodied than any other pair you will find out there, the OTL sound does not seem to suit them as well."

I may misunderstand your point, but does "your Coincident" any different than mine? Did you have mod one them? Or are you referring to other brands of speaker?

Also another question for you: does Israel chooses Transformer coupled amplifiers lately may just because there isn't many OTL on the market? Just a guess.

Oneprof:

When I taked to Allan, he only mentioned optional internal silver wiring upgrade. Any other upgrades out there?

Artg:

It sounds we have the similar concerns and reasons to choose Berning (though I haven't 100% decide to go with Berning yet, see below). Berning may not be perfect but it gets 95% things there without other headaches.

Sutts & Metralla:

Interesting. I also have a Welborne DRD 300B (8 watts) ultimate version and pairs with my SE III sounds great with solo and chamber music. It does run out of steam when Mahler is played. Currently, I interchange Welborne with a NAD C272. The NAD sounds good but not great. On music of Mahler, it clearly betters the Welborne in terms of dynamic which Mahler's music really shine. I even open to consideration for the new Pass Labs X.5 amplifier for orchestra music. I know, I know, solid state never gets the sound of tube, but does Berning really outclass Pass Labs in terms of dynamic, attack, smoothness, and transparency where modern symphonic works really need? Do I get 90% of the Berning if I choose Pass?
For those who haven't kept up with everything, Ralph has ALWAYS favored the old chassis of the M60. It's his seminal design, it is HIS amplifier (in any and every way you can think of). If you put a gun to his head and told him he could only make one product, this would be it. As a picture is worth a thousand words, you can see that he has returned to what he believes in. We should ALL be ecstatic about that.

John (Sutts) and I almost always agree, as we do here. So, a classic tube amp seems to be the way to go with the Coincidents. I will say that a good friend of mine ended up with the Coincident Triumph UHS because they were one of only a couple of speakers that we found that could be driven with his absolute flea powered AudioValve integrated - supposedly 25 watts, but it sounds like 3 wpc to me.
Sutts writes:
smaller Victory .... which is really the ONLY Coincident speaker in my humble opinion that can make do with an SE amp <20 watts

I use Super Eclipse Series II with 8 watt 300Bs (Welborne Lab Laurels Ultimate Upgrade) and in my apartment they are superb. Obviously I don't listen at high volumes; and the original poster likes "20 century's big symphony orchestra works" so I can see that he needs more power than I do. We have the same size listening room though.

Sutts, thanks for your insight into the Coincident models you have owned. I was at CES last week and Israel was making nice music with Super E Series III and Manley amps.

Regards,
I have owned Coincident Super Eclipses; smaller Victory; and for the past couple of years the Total Victory. I have used many different amplifiers on them, and have found a good push-pull triode circuit to me most effective (especially on any of the models BUT the smaller Victory, which is really the ONLY Coincident speaker in my humble opinion that can make do with an SE amp <20 watts).

The Super E's do like a bit of power (amps that have worked well on them in the past for me were the 1009 60-watt ASL PP triode 845 monos; and a very cool set of modded Altec 1570B's using a pair of 811's per amp- they were fantastic with the SE's. Trelja made a good point though- the Super E's WILL show up ANY harshness in upstream componentry, so audition with the speakers IF you can...

I have even bi-amped the Super E's in the past, which can produce fantastic results, and I am about to try it with the Total Victorys- ARC VT100MKIII on bass/mis-bass; and a customized pp2A3 on mids/ribbon tweeter- it's going to be a fun experiment!

In summary, to Trelja's other point, Israel is definitely in the transformer-based tube amp camp, and as I live 5 minutes from him, we have had a lot of fun trying many amps with all of the Coincident speakers. Our most recent experiment was a set of the Dehavilland 50-watt GM70 SET monos. Except for not being able to rock and roll too well, the were superb on the Super E's- excellent detail and delicacy- on the smaller less 'hungry' Victory, I could probably live with them, as I have become a big fan of the medium-high power big triodes (845; but even better the 211). One day for a second system, I want to get back to the smaller Victory's in a smaller room with the Air Tight ATM-211's- something tells me that would be a magnificent combo...
hmmm bery interesting thread. i had the Atma's in my system (the MA-1's) and loved them with my Sonus Faber Guarneri Homage's, in fact i liked them much more than amps from VTL, AR, Bel Canto and CJ. Ultimately, i preferred the sound of the Atma's, but but there were some serious practical considerations - heat ( A LOT OF IT, which is ok in MN winter, but any other time of the year, forget it), open tubes (i have a 2 and a 4 yr old), monoblock design and upkeep(not cheap).

Still, as i have mentioned in other posts, i was still ready to buy a set - then i bought the Berning, mostly on a whim, and have not looked back. It provided 95% of all that 'magic' that atmas did, yet gave better bass and dynamics, and runs only as hot as a 300 watt light bulb. I love this amp more than anything else in my system (well, equal to the Guarneris)

Having said all that, i think both are excellent, but for my $, the Berning is a better all-around performer, and has all those built-in practical advantages.
For the record my ZH-270 is partially modded. It has the cryo output tubes/ERS mod. And I am using Merlin VSM-MMs right now.
I too have found the Atmasphere amplifiers to be superb. Certainly one the best amplifies that I have heard. Although the Atmasphere may be more fussy about speaker impedance values, and swings, this can be mitigated with the use of the Zero auto-transformer, a device which effectively optimizes the impedance match between the amplifier and the speaker thus allowing the amplifier to synergetically mate with a speaker and realize all the desireable attributes of the OTL design.

I have run both the MA-1 and MA-2 with, and without, the auto-transformer on my Magnepan 3.6's. Also with the MA-1, I pulled tubes to emulate the M60. With the auto-transformer, the vibrant and delicate soundfield was downright arresting. It just sounded like it was suppose to sound - very immediate, very lucid and very real. Nothing hyper-uppered about the Atmasphere.

Speaking about the M60, there is a picture of the new M60 that Ralph is making on one of the sites covering the CES show. It's nice looking unit. I don't know if it is any different to the venerable M60 but, it's worth checking out.

Laoyuap, just to complicate things a little more, the Berning with all of the mods that Allan Bhagan has come up sounds notably different than the stock Berning. Neither Duke nor Swampwalker indicated whether they heard a stock Berning or a modded one (although I seem to remember from a previous thread that Swampwalker heard a fully modded one? Not sure). I think that most of us Berning owners have gone for the mods, and are very happy with them. Of course, the modifications do cost some additional money, but IMO the mods are worth it.
As our very dear friend Michael (Swampwalker), has owned the Berning ZH270, AtmaSphere M60, AND a Joule Electra, he is the authority here. From his experiences and perspectives, which I trust a great deal, the Atmas are a bit warmer and richer than the Bernings. This would suggest a better marriage with the Coincidents...

But, as Spencer pointed out, with my Coincidents, which are incidentally warmer and more full bodied than any other pair you will find out there, the OTL sound does not seem to suit them as well. Not that the sound is bad, but it is does have a bit of harshness and brightness that I was never able to get rid of with my MKII.2. The MKII.3, plus a lot of upgrades instills the liquidity that I need into the sound.

Still, after the holidays with my Granite monoblocks, and ESPECIALLY this past weekend with my Jadis, I am more or less convinced that the Coincidents sound best with a transformer coupled tube amplifier. I know that the rumor is that Israel Blume has used the M60s to voice his speakers (and a call to him will show he knows A LOT about the amps), when he released his own line of tube amps, they were transformer coupled SET 300B based. And, at CES, for the past several years, he has partnered with EveAnna Manley, to rave review.

In my experience, an OTL amp seems to mesh better with a more relaxed speaker, such as Spencer's Merlins. That Dynaudio Esotar is a much smoother tweeter than the ScanSpeak Revelator used in many of the Coincidents. This is not to say which tweeter is better or worse, as both have their legions of devoted followers.

And, for whatever reason, as Spencer said, my specially modified pair of Frieds (they were Bud's own pair up until we got him a new pair of Studio VIIs this fall), seem to just make really good sound with the AtmaSphere M60s. I think it's the "resistive load" loudspeaker that meshes so well with the OTL (remember, Ralph owned Frieds for so many years).

For what it's worth, I am not a fan of running less tubes in the Atmas. Yes, you'll throw off less heat. Yes, you'll use less electricity. Yes, this. Yes, that. But, if you are really concerned about these issues, I would say that the sonics of the two amps are probably similar enough to say that the Berning would be the obvious choice.
Laoyuap-
Duke's comment "At that which they do well - which is lifelike timbres and textures, engaging liveliness, and rich inner harmonic detail - the Atma-Spheres are truly superb." is right on the money. I listen to mostly solo and small combo, non-amplified music (folk, blue-grass, blues, some jazz, lots of singer-songwriter stuff, some older rock), and those qualities are exactly what I value. I don't have any experience with either of those amps with full scale orchestral type stuff, bu the solo violin and chamber should be great with the Atmas. I think the Berning is more neutral, faster. The best way to explain it in terms of your musical tastes (forgive me if I'm way off base, I said I'm no classical fan) is just different readings of the same score, or different character of 2 different, great old violins. As far as the practical aspects go, the Berning is the clear winner. Besides those noted above, the Atmas are monoblocks AND (a very big and) laid out with the inputs and the outputs both in the front of the amp (may have changed on new versions). This is a a pain, since with manual biasing (no big deal by the way), you need visual and manual access to the front of the amp, which is where the input jacks and speaker posts are, but the power cord IEC is on the back. If you can place them behind each speaker, with a long IC and short speaker cables, it might work out pretty well, but then there's the kid-factor.
Hello Laoyuap,

Yes you can run the M-60 with only 4 tubes per channel. With most speakers that probably wouldn't work well, but your 14-ohm Coincidents are a special case.

When you reduce the number of output tubes in an Atma-Sphere amp, you not only reduce the power output but you also reduce the damping factor (or increase the output impedance - same thing). This means that the bass will not be as well controlled, with most speakers. But if you have high impedance speakers like yours, the bass will probably still be well enough controlled, and the combination should work very well. And the midrange might be just a wee bit better with fewer output tubes.

I don't know of any other amplifiers where you can safely remove output tubes and still operate the amplifier. I'm sure they exist, but just don't know of any offhand.

Best of luck to you,

Duke
Swampwalker & Audiokinesis,

Thanks for the input. It appears personal taste do invole in the decision of choosing hi-end component based on sound even for an amplifier which supposes to just amplify singals.

Audiokinesis, interesting point:

"Note that you can also run the Atma-Spheres with less than the full tube complement, reducing the heat output and still sounding excellent"

Does this mean I can use 4 output tubes per channel and get half of the power? Does it applies other Tube amps as well?

Again thanks for input.
Hi, Spencer,

You opinion really help. It gives me more solid affirmation for my thinking. Regarding the combination of Coincedent + M60, I thought Israel voices his speakers on Atma-Sphere especially M60 Mk2, maybe I remembered wrong...

Thanks again.
First of all the disclaimer: I am a dealer for Atma-Sphere. I once owned and do think highly of the Berning amp, though I'm not a dealer for them.

The reason I did not become a dealer for Berning is that I preferred the M-60 in a side-by-side comparison in my system, driving original Quad ESL's (the "57's") and some home-brew dynamic speakers. I have heard the Berning and M-60 driving Merlin VSMs, and once again preferred the M-60. I find it to be more lively and have a richer texture, drawing me more deeply into the music.

That being said, the Berning has a lot going for it. It sounds great, is very lightweight, cool-running, and can be used without a preamp. The variable output impedance control is a wonderful feature that I'd like to see on more amplifiers. Pound for pound, the little Berning is more than likely the best amplifier made.

The Atma-Sphere M-60 does require periodic rebiasing, but that takes about one minute and the only tool required is a screwdriver. You also need to observe the turn-on switch sequence, so it's a bit less user-friendly if non-audiophile family members will be operating it. While the M-60 can accept single-ended inputs, it sounds best with balanced inputs (though in the side-by-side comparison I mention above I used single-ended inputs because at the time I didn't have a balanced preamp). Note that you can also run the Atma-Spheres with less than the full tube complement, reducing the heat output and still sounding excellent (and maybe even better?) with a high-impedance speaker like your Coincidents.

I have the impression that the Berning is comfortable with a wide range of loudspeaker impedances (the variable output impedance helps here), but the Atma-Sphere M-60's don't like speakers with impedances below 8 ohms unless the impedance curve is smooth and the efficiency fairly high.

The Berning is a very fine-sounding amplifier and offers an excellent collection of qualities at a very reasonable price. Sonically it's probably among the top 10% of amps in its general power and price range. Given appropriate loudspeaker matching (such as your Super Eclipses), the Atma-Sphere M-60 is the most musically engaging amp that I have heard in its general power and price range (the 27-watt, 845-tubed deHavilland SET is also excellent, though I don't sell it). At that which they do well - which is lifelike timbres and textures, engaging liveliness, and rich inner harmonic detail - the Atma-Spheres are truly superb.

But remember I'm a dealer, fin on my back, toothy grin and outstretched hand...

Duke
I've never heard either of these amps with co-incidents, but I am one of the few that found the Berning a little more analytical than the M-60s (2.3) with merlins. But if you have young kids, and the amps will be where they can reach them, then that may be the deciding factor. As you would expect, the Atmas run quite hot. Ouch. Sonically, you won't regret either one.
Laoyuap,
Hopefully this will help...
I own a Berning ZH270, and have heard both amps. Both are share many similar attributes in their sound, but for my ears, the Berning is playing in a different league than the M60s. Your observations about both are spot on. As you state, the Bernings relative lack of heat, small chasis size,auto-biasing, remarkably long-lasting tubes and volume control are all good things. However, the reason I bought the Berning is simply that its sonic performance is amazing, especially at its price point. This and it's resale value, should you ever have to sell, are the best reasons to go with a Berning. Allan Bhagan and David give excellent support with upgrades and service questions. Repairs are rare from what I've heard.
Both of these amps come from fine companies. Ralph Karsten is a great guy, and I have many friends(regular A-goners) who happily listen thru Atmas.
I've heard the M60 with Coincidents, and it wasn't the best combo compared to some modified Frieds with the M60. Contact member Trelja for more details, this is his gear.
Cheers, Spencer
Hi, Tom:

Thanks for the response. I may have already made the decision but just want to hear opinions from product owners and have final check in case I miss something. I haven't heard either one before and spending close to $5k makes me a bit nervous.

Thanks again.
It sounds to me like you've already made the decision, because of the items you listed being already in favor of the Berning amp.

I use Berning amplifiers and their sound quality is extremely good, tube life is much longer than most amps, ease of use is simply "plug and play", it doesn't get very hot, and has excellent resale value.

David Berning's product reliability rating is one of the very best in the industry, and his products are well-known for reliability.