Price Paid:  $6000.00 from used

Summary:
Extremely engaging. Match this amp with any compatible speaker and forget about upgrading forever.

I purchased mine after reading reviews here and have been absolutely thrilled by their performance ever since.

ZERO autoformers from www.zeroimpedance.com provides compatibility with a wider range of speakers.

Pair with an Atma-Sphere preamp for even greater thrills. Stating my complete satisfaction seems like an understatement.

Do not overlook these amps.

Strengths:
Very realistic presentation, meets every demand presented with authority and finesse.

Weaknesses:
Heats up room during short season when heat or air conditioning are not required. Very small price to pay for glorious performance.

Similar Products Used:
None

Summary:
It just seemed logical that removing a hunk of iron encapselating a bazillion turns of wire from the signal path couldn't help but clean up the sound. Life is filled with resistance, and the less you have to endure, the sweeter the quality.
Output Transformerless Amplifiers do this and the end result is just not to be believed.
I could go on and on about the sound but others have done it much better and you just have to hear it with your own ears and heart.
I would, instead, like to address the issues of OTL "Bugaboos" that appear from time to time in the press and on the street.
"They blow up and take your speakers with them'
Some older and not very sophistacated designs were know to do that, but we are in an age of modern design that makes that rhubarb as obsolete as old circuits.
"They run hot"
If someone were capable of designing a "sand" swithcing device with the same cubic centimeter surface area as one 6AS7G tube, the room would ignite. Have you ever been in the room with a large "sand amp" like Krell? Remember, everthing is relative.
"They require a lot of tending to"
Some people are desperately quite in their contentment with having a large black box for amplification that they can turn on or turn off.
Twaddle! If your passion for musical recreation is that subdued, your don't deserve to bask in the glow of those magnificent tube clusters.
Lying on the floor to gentle activate the bias control switches and watching the amp meter slowly reach it's numirical destination and then very carefully and ever so slowly making the most minute adjustment will give you one of the most viseral audio orgasms that you may ever experience.
Don't be freightned by at the unknow. If you need help, contact Ralph at Atma-Sphere, he built them so he should know, and he will gladly set you straight. Or go on line to the ASOG site and any problem subject will be addressed ad nausium.
Life is short. Design a system around these amps and every muscal moment will be more meaningful.

Strengths:
A whole new deminsion of OTL clarity.

Weaknesses:
See review summary

Similar Products Used:
VAC's, VTL's, home grown

Summary:
They ARE the Music.
Perfect amps? The best of all possible worlds .The Atma-Spheres breathe in and out like the music breathes in and out, nearly impossible to do for Transistor Electronics like this way, one of the best amps ever designed is the Pass Aleph 0, single ended transistor design.
Super fast, ultra clear, extremely precise and the M-60 MK II.2 are in the same league.
They are the King of Speed.
All other tube amps ( Jadis, Wavac, Lamm, Convergent ) had some strenghts and I liked them but none of them is so complete from the dynamic range like the Atma-Sphere.
Speed, control, dynamics, timbre, timing, clearness, bass surrounded by air is unique.

The designer is a genius.

System's Components:

Turntable: Basis Debut Vacuum Mk.V
Arm: Graham 2.0 Deluxe
Cartridge: Takeda ' Miyabi '
CD Transport: Goldmund Mimesis
D/A Converter: DCS ' Delius '
D/D Converter: DCS ' Purcell '
Phono Preamp: Stan Klyne 7 PX 3.5
Line Preamp: Stan Klyne 7 LX 3.5
Power Amps : Pass Aleph 0
Atma-Sphere M-60 Mk II.2
Speakers : Köchel K 300
Tuner : Magnum Dynalab 'MD 108' +
Magnum Dynalab 'Signal Sleuth 205'
Headphone : Stax Signature System II
Interconnects: XLO Ltd. Edition
Phono Cable : XLO Signature
Speaker Cables: XLO Signature Shotgun
Digital Cables: XLO Signature AES/EBU
Power Cables: XLO Ultra
Record Cleaner: VPI HW 16.5
Power Conditioner: Burmester 948

Summary:
Though the ATMASPHERE amp's are not very known and sold
in Europe, the MA-2 model which uses 50[!] tubes altogether,
is even more of a strange beast.
I have liked OTL's a lot, they have an opennes and clarity
only OTL's have ! In my audiophile career i have had the
oppertunity to listen to many fine amps,and even listened
to the most extravagant.
before the MA-2's, i have had a pair of JADIS JA-80's, which
i thought were very fine amps...[they actually are..]
Then entered the MA-2..
on first impression i could not believe this all could
happen.. and after about half a year and some finetuning,
i still am surprised every time i listen to them, no matter
what music, every time i feel like a kid who watches a
great firework for the first time in his life...
they are that good.
my rig consist of other great gear like a CAT pre-amp,
VERDIER turntable, VOCE-DIVINA speakers, and is very
revealing towards pressings and recordings.
The ma-2's are power amp's for sure, but show every subtlety
in the front-end, be it VTA or pre-amp tubes been used.
A VERY open window indeed, forget about tubey sound,
forget about limits, roll-offs, "can be only used with"
Forget about everything you have heard before....
Yes they carry a price tag, and yes every word i said
comes from my heart.
I have bought mine without even listening to them first..
WHY ? because i have heard so many enthusiast ATMASPHERE
owners raving about all models, and i ran into a usedpair
in Germany..,i followed my heart, just like that.
You should be able to listen to this amp more easily in the U.S. since it's the homemarket.
I'm so proud to own these amps, and there is even a very
enthusiast website with an owners group, so every question
asked will be answered.. you may even contact the factory
and get instant reply from the owner and maker of these
OTL amps. try this with other factory's.. Ralph Karsten is the man behind all this, and he needs no advertising atall.
He's been making these amps for 20 yrs now, and i'm sure
he will be still there the next 20 yrs !
These Amp's are here to stay, only an factory upgrade will
be done to MK-2 spec's in the future.

Strengths:
unlike most modest OTL amps,these amps have control,slam,
power,and a finesse about it's sound only OTL amps have.

Weaknesses:
These beasts eat up more than 1200 watts of AC power,produce
heat like no other amp, and want to be taken care of.
they are absolutely dependable, but need an understanding
owner. i'm not into soldering however, and leave that to
qualified's

Similar Products Used:
Just the power-amp's from ATMASPHERE.
high-end rig sums up to about 50 k total.

Summary:
The Atma-sphere MK60 II is a great monoblock pair. Fast, transparent and OTL for an incredible price. The units feature balanced or unbalanced inputs. A simple system for setting bias is provided. The MK60s drive B&W 801 Series IIs with no problem. The source is a Wadia 850 CD connected directly to the MK60s (no preamp). I highly recomend the MK60s, they are one of the best amplifiers I have experienced. They are 60 watts per channel and prefer driving 6 ohms or more. You owe it to yourself to hear these amplifiers.