Atma-Sphere S30 MKII

Does anyone have experience with the ATMA-SPHERE S30 MKII?
What preamp,speakers,cables do you use?
Hi Johnny7: Check out the APOG.

Absolute best source I've seen for you is the APOG (Atmos-Phere Owners Group) at Site includes an OTL Online Forum of all atmos-phere junkies. There are a few great articles there too. Read the one by Tomcik called "The Missing Link in Speaker Operation." Best explanation of damping and speaker matching I have ever read and essential to read if you are trying to match speakers and cables to your OTL. I think it dates from 1954.

Sincerely, I remain
APOG??? Its the ASOG.

I remain,
Hi Johnny
You may be looking at the last amp you will buy in a long time, at least thats how I feel.
I have my S30 paired with Reference 3a Decapos at the moment. Prior, I had Soliloquy 5.3s. Both very compatible with the S30. You may also consider Coincidents & Meadowlarks.
The S30 has proven itself to be very reliable with an occasional tube replacement. 6AS7s are relatively cheap ($13) & plentiful.
Read the many reviews of the MK60 at the Atmasphere website.
All the accolades can be applied to the S30 as well.
Hi, Johnny7. Feel free to go to ASOG but it appears ASOG is coming to you (Hello, Emil). I'm currently using an S30 with the alon lotus SE with the 14 ohm woofer. The amp is exceptional and while not cheap is, IMHO, one of audio's great bargains for what you get. My path to the S30 was anything but a straight one. My original plan was to buy the lotus's and pair them with a SET amp. I auditioned the cary 300 SE monoblocks but were underwhelmed especially for the price($6000). I had seen the S30 at the stereophile show in Chicago(1999) and figured I try them since they where offered with a 30 day trial and cost half what their SET competition was going for. The S30 replaced an excellent Audio Research classic 60. The S30 has incredible speed(the first thing you'll notice) as well as the expected excellent imaging , transparency and midrange. What will also surprise you is the quality of the bass. Even though it has half the rated power of the classic 60 the bass was actually better. If paired with a speaker like the coincident total eclipse(10 ohm impedence, flat to 25 hz) the bass can be phenomenal. If I had'nt found the S30 I'd probably gone for the VAC 30/30($7000).

AS for what speakers work well with the S30, anything that works well with SET's will do fine with the S30, >6 0hms impedence, 90db sensitivity or greater as a guide.

The S30 has inputs for both single ended rcas'a and balanced
XLR's. Currently, my preamp is an Atmasphere MP3, another under promoted gem. (well, what did you expect me to do with all that money I saved with the S30?). I'm using balanced goertz TQ-2's. Prior to the MP3 I had an AI mod3 and used an old pair of audioquest emerald's single ended rca's with excellent results.

This has turned out to be a little more of a love letter than I had planned(it is valentine's day,you know) so for the cynical out their, I am not a dealer for nor do I have any relationship with Atmasphere, just a happy owner.
I have M60s with Merlin VSMs (tube friendly impedance, 89db), and reason to beleive the S30 might work as well or better becuase it is "simpler"?
The signal paths of the two amps are the same. The Merlins appreciate the extra power though.

BTW the ASOG site got shut down in October of 2004. A good portion of it is archived on the OTL Asylum at
What is the proper method for removing output tubes to lower the power? Any downside to doing this? Rising output impedance?
in the S-30 you can just pull power tubes. My speakers work fine with 3 per channel, but they are about 97 db 1 watt/1 meter. The output impedance does get raised so with certain speakers you might introduce a coloration.
Thanks Ralph. I think I'm going to use the M60s as is and just enjoy the music. To my ears your amps and Merlin VSMs are about as good as it gets. Looking forward to the 3.1 upgrade.
how would the s30 work with a 16 ohm load?
Selling an older model s30 was one of my biggest mistakes in 35 years in high end hobby, and I've swapped out a lot. Great amp, if you have enough ventilation in your room.
Rontaylor, the Atma-Sphere S30 should be fine with a 16 ohm load. I've been told that it's ideal loading is 12 ohm and 16 should be no problem. The only possible challenge is if the load drops deeply somewhere along the frequency spectrum. The best answer will come from Ralph at Atma-Sphere. Give him a call him and tell him what speakers you will be using.
From the Atma-Sphere website about the S30:

Output power
30 watts per channel into 8 Ω load
45 watts per channel into 16 Ω load
Rontaylor and Rushton,

Speltz Zero Auto-transformers can solve some problems. I use them to good effect in my system.


I have the S-30 and would never part with it. But it does generate a lot of heat, which is a challenge in the tropics.