Atma Sphere S30 amp

I got my S30 amp yesterday and got in 12 hrs. of listening time with it.

Having started off on this audio journey with tubes I got lost somewhere down the road with SS amps. A friend of mine sent me a demo AA PX25 to try out with my Zu speakers and I was in shock on how organic sounding this little 6W amp sounded and I soon realized ( in 5 min.) I screwed up big time. My amps sounded plastic/fake and after reading a review about the AS S30 being a better all around amp than the PX25 and with more power I bought the amp new.

Even with stock 6sn7 tubes this amp is a keeper for me. I could have had listening to a OTL all this time and feel I wasted alot of $$$ and time on my SS amps. You never know until you buy and try.

This amp is not for everyone but for Zu owners I would encourage you to try this guy out.

Thanks to all you OTL owners who have posted here in the forms and for Pubul57 whose knowledge of these amps made my purchase an easy decision.

Hiphiphorray I am back with tubes and loving it.


What kinds of music do you listen to?

I'd be interested in your assessment on any particular CDs or albums that you might provide.
You just helped me make a decision I was struggling with. The S-30 was used in the voicing of my speakers, so I've been wanting to try one. Now I definitely will.

The S-30 would be my third tube amp, along with a Music Reference RM-10 MkII and VAC Auricle Musicblocs. Problem is I don't need 3, so one of the other two will have to go to offset the cost (most likely the VAC, which in some ways would be painful). Decisions, decisions.

That amp and your speakers looks like an AWESOME combo!
Don't sell the RM10, you'll only buy it again later. Anthony, are you light loading the RM10? Using the 4ohm tap? Try it, you'll like it.

It's all about system synergy. I replaced several highly regarded tube amps with SS amps and boy I can't believe what I had been missing:-) Really!

Now, I had the same thing happen in reverse with different speakers. It is all about the speaker/amp synergy folks. This is not a tube/SS thing IMHO.

I do love tube amps however and will always keep my tube preamp no matter what amp/speaker combo I have.
Paul, I think I am light loading the RM-10 MkII. My speakers are 12 ohm nominal (no lower than 8 ohm dip) and I'm using the 8 ohm tap. Wouldn't this be the equivalent of using the 4 ohm tap on 8 ohm speakers?

Right now I'm leaning towards selling the VACs as they will fetch a lot more. Problem is you rarely see the 70 watt Auricle Musicblocs for sale and the cost to buy back in to VAC is quite high with their newer products. Can't justify keeping all three. I need to clean the garage this weekend.

Good luck finding a used S30 on the 'Gon. Some M60 amps have come and gone but living in FL. with M60 amps would drive me out of the house in the summer.


Take Eva Cassidy's Blues Alley. I've listen to it hundreds of times but never heard it sound live like I did today. No grunge/gradu in the way of the music. I don't want to go to work during the day. I never put in 12 straight hrs. of listening time without a break.
Anthony, you are light loading, you might want to discuss with Roger, but I suspect if you us the 4ohm tap you will get even less distortion, more current, and tubes will run much cooler and last even more than the expected 10,000 hours. I also suspect that the slight reduction in power would not be noticeable with your speakers. And best of all, those amps are really designed to by run with a passive preamp:) I know what you mean about the VACs, but if you stay on your high efficiency kick, you may never need more than those 30 watts!
Glory, I plan on buying the S-30 new.

Paul, I will try the 4 ohm tap. I've been trying to reach Roger with no luck. When I lived in Santa Barbara he was more accessible. I'm going back for a visit in a couple of weeks and if I don't hear from him before then I'm going to drive to his house and knock on his door.

The Clio 9 passive volume attenuator and RM-10 MkII are getting along just fine.
When you get a chance, e-mail me details about your passive and your thoughts behind it.
Glory, congrats on the discovering the magic of Atma-Sphere amps coupled with the right speaker. I love my M60's with the Defintions.
Clio09 I see you have a pair of Jazz Modules. Those 70 watt KT88s don't do it for you? Coincidently I'm going to listen to a pair of Jazz Modules this weekend and I'm bringing along my Berning ZH270. I'm actually more interested in how the an 845 SET amp handles the Jazz Modules as opposed to an OTL. I'm moving away from OTLs. Still I would be curious of you opinion on the S30 paired with the Jazz Modules if you go that direction.
The VAC amps and the Jazz Modules are a great match. Just want to try the Atma-sphere since it was used in the voicing. At 12 ohms the VACs put out closer to 55 watts (maybe since it is the 8 ohm tap too) while the S-30 would be closer to 40. I don't think 15 watts is a big difference with these speakers.

If you like the Jazz Modules get them while Duke still has the TAD drivers.

The Berning would be another choice. I have the Micro ZOTL and use it as a preamp on occasion.
I would love to hear your impressions of the S30, as you know I was listening to the CAT JL2 and Music Reference RM9 Special Editon (neither chopped liver)when I finally came into the Atma-sphere fold. My sense still is that of your speakers can work with an OTL, there is no better "type" of amplifier.

Wow you went from a CAT JL2 to the M-60s?! That really says a lot about Atma-sphere's OTLs.

I too have Merlins (actually we almost have identical configurations with the exceptions of the amps). I've had both the Joule VZN-80 and Berning ZH270 (as well as the Ars-Sonum), but never an Atma-sphere OTL. I would have loved to hear that JL2 or a Vac PHI 200 at this point. The Merlins with the most recent lead free mods are incredibly resolving(!), if that's what you like, and with the Berning it makes the sound even more transparent and up front. I can no longer listen to a lot of my favorite CDs because of the recording, and I'm torn as to whether this is a good thing! I told Bobby that I want my lead back, but instead of selling the Merlins, as I mentioned before, I'm moving away from OTLs and will be seeking more warmth. Still I'm curious about the S-30.

I listened to the Jazz Modules on Saturday. I brought along my Berning ZH270, but unfortunately I wasn't really taken with Jazz Modules and Berning combination. The highs were slightly bright and thin, and I was still missing a lot of the spaciousness and loftiness of the mids. Jazz piano is my thing. In an email reply, Duke mentioned that he voiced them using the S-30. I would expect the S-30 to be a bit more resolving than what I'm looking for. I much preferred the Jazz Modules paired with a 10 watt 6v6 pp amp and would further like to hear them with a 300B or 845 amp. I'd keep your VAC, but that's my preference and I seem to be in the minority on getting more out of the mids (Merlins included).
Dpe, you might want to try the Music Reference RM10 MKII for a little more "tone". I think you can get them for $1,000 or so, PLEASE don't let the low price fool you.
Pubul57, thanks for the advice. That's 22K cheaper than Bobby's suggestion: Audio Aero Prestige amplifier.

Interesting thoughts on the Berning/Jazz Modules combo. I was always intrigued by Berning and like the Micro ZOTL. Perhaps they just don't match up well in this instance.

The VAC amps do offer nice mids, although the EL-34 models more so than the KT-88s IMO (I have owned the Avatar SE and Williamson 35/35). The fact that they are highly compatible with the Jazz Modules is a plus too. One thing I am considering is keeping the Musicblocs and converting them to EL-34. VAC has indicated this is easily doable.

Pubul57 is right about the RM-10MkII. This has to be one of the best amps out there in the 25 - 50 watt range. You can't argue with the used prices either. Amazing benefit to cost ratio.
I mentioned this in another thread but I have just under $1500 invested in the amp and preamp used in my system right now (new just under $2500). I'm going to go out on a limb and say the sound I'm getting makes their valuation worth closer to $15k.

I'd pass on that $20k plus amp too.
The RM10 will never break and it will give you 10,000 hours of tube life. Try it, if you don't like it will take you 4-5 hours to sell back on Audiogon. $20K is an awful lot of music:)
Pubul57, we're getting a little off the topic with regards to the original post, but how does the RM10 sound with your Merlins?
Very close to the RM9 Special Edition that costs $9,500 - just a little less sense of scale, to expected with its 162 watts, but they are certainly cut from the same cloth. Now if I were choosing an amp for the VSMs and could only have one, it would be Atma M60s for sound, but that does come at a price of tube maintenance and heat, but it is the best I've heard the VSMs sound, I prefer them to the Joule amps, but others will prefer the Joule - they both mate well with the VSMs. I would think the S30 is not ideal for the VSMs, I think you really need the M60s if you go in that direction.
Glory, could you expound on the differences you experience between this amp and your Red Wine 70.2 monoblocks? What prodded you to make the jump for these?
FWIW the reports we have say that the S-30 drives the VSM easily, as well as the TSM.
Maybe, but the M60s are better yet. I've not yet heard an amp that sounds better with the VSMs, and I've been trying a lot of them.

As I mentioned I owned the Joule VZN-80. For the most part it was a wonderful amp although occasionally a little shrilly in the highs and I wouldn't call it a full spectrum sounding amp, and it ran HOT. I will say that it provided wonderful mids like no amp that I've ever owned. I should have kept it and sold the Berning instead, but the 15 lbs Berning is so portable I can take it anywhere or use it for my A/V setup. I sold the VZN-80 to fund an Ars, and then sold the Ars in less than a month (granted it was an SE, but not the newest newest(!) version). I've been seeking to regain the wonderful textured midrange with a lack of sharp or thin highs.

It's good to hear that the S-30 easily drives the VSM. It would surely be worth a listen.
Dpe, I think all the amps under consideration are going to be good. What did the Ars do that wasn't your cup of tea? By the way the Music Reference gear, both RM10 and 9 is neutral, even though the RM9 uses EL34s. I have all three, Atma and the two Music References - I love them all. But I guess if I had to only have one I would go with the Atma-sphere. If you love the S30, I can't imagine you won't head towards the M60s down the road, though they too run hot as to be expected from Class A Triode with all those tubes.
Glory, congratulations on your S-30 purchase. It's a great amp. I suspect that if a lot of the flea power owners had the opportunity to try it in their systems, they would never look back.

Like Clio09, I own Audiokinesis speakers (Planetarium Betas), which Duke voiced with the S-30. These replaced far more expensive gear (SoundLabs and Ayre MX-Rs), yet I've never been happier with my system.

Bottom line - if you have relatively efficient speakers with a benign impedance load, the S-30 deserves serious consideration.
Welcome aboard. I'm an S30 owner going back to early 2000, just a few months after it's introduction at the sterophile show in Chicago.

I just had mine upgraded to 3.1 status from mk2 and it's a "wow". If your an Atmasphere owner I highly reccomend the upgrade(in fact, it's kind of a no brainer). When time allows I'll post further.

Glory, you may want to contact Shawn at Zu. We were discussing the Essence and apparently they are capable of producing a main driver with an even higher impedence from 16-24 ohms for OTL owners. That would be ideal for the S30. I have no idea if it's available/retrofitable for the Presense but it's certinly worth a phone call.
Any firsthand experience using the s-30 with the Zeros?? As the recommended minimum impedance is 8 ohm, I would assume that this would preclude a great many speakers being used. The Zeros would solved the impedance issue, however do they in any way impart a deleterious effect on the sound?
Weebeesdad, how that seems to work is that if the amp does not work with the speaker due to impedance, its a moot point as to the effect the ZERO has, and in practice it does quite well.

The gray area is in dealing with speakers that are right on the fence impedance-wise. Sometimes you are better off without.
Weebeesdad, in my opinion if the impedance stays above 7 ohms or so and is smooth (no big impedance peaks above the bass region), the S-30 is often still a strong contender. The S-30 will deliver increased power into an impedance peak, which is why you don't want such a peak in the midrange region. Now if a speaker does have a single impedance peak in the midrange but is otherwise a good candidate for the S-30 (no nasty impedance dips and decent efficiency), it some cases it is possible to design a circuit that equalizes that impedance peak. I did that for someone with upper-80's efficient monitors that stay above 6 ohms and he was pretty happy with the result. Contact me if you'd like a link to some online comments he posted.

I replaced the 6sn7 tubes with Raytheons flat plates, Sylvania BB/Sylvania GTA. I tried the RCA Smoked glass GT but lost the soul and texture of the music. Maybe for you but not for me with the RCA GT.

Well these tube from Absolutetubes (Jim Sautter) have taken me for a great ride. Somehow I got lucky and picked the right combo of tubes to give me the sound I want.

This amp is much better now with these tubes in place than the AA PX25. The demo PX25 amp got me to think that the RWA amps were not the best amps for my system. Wow, am I a happy camper.

Thanks again to 57 for his time/wisdom in helping me buy this amp.

Here comes the Dude!!!!!!!
It's always great to read about someone trying out Atma-sphere gear for the first time. I went from user to NYC dealer.

My journey with Atma gear has been over twenty years. I like to think what they do best is not necessarily a frequency thing or a staging thing, nor are they warm, or for that matter cool. I just always felt they gave a tremendous amount of shear musical gestalt - that quality of vitality that imbues recorded music with the essence of the performer that got me closer than anything else I listened to, tube or SS, in my system or others I have heard.

It's true I have heard some other amazing systems, but the gear sells for many many multiples of what Atma sells for.

Absolutely try the Zero's . You can get them on a trial basis I think.

Having used them on a number of speakers, the Zero's can make things better on 8 ohm and under speakers, especially if the bass seems a little uncontrolled. If there is no benefit you'll hear it, but I'd suggest having a set around just so you could try your OTL's with other speakers at friends, stores, etc. Especially as the S-30 is compact compared to my MA-1's.

You can get the OTL to work well with almost any speaker using Zero's to get to the optimum impedance.

Also there is an amazing synergy between their amps and pre's if you get a chance to borrow one.

The latest versions of both the amps and the preamps have elevated the gear to that afore mentioned echelon. Ralph Karsten's continued discoveries in Vacuum tube circuits has now created (with the M-60's and above with an Atma pre) I believe, "set for life components."

Anyone (save for those that just truly enjoy playing with electronics rather than playing music,) can now rest assured that they are getting such a high degree of realism and enjoyment, that any further desired upgrades in sonics are really now about tube rolling, ac cords and conditioning, cables (and a few other things I've discovered), and about the other gear in one's system, not their electronics.
Not that I'm changing, but there is a possibilty that some of this thread would have some opinions on the differences between Atma-sphere and Joule OTL amplfiers (I do own a Joule and Atma-sphere preamp).