Amps Atma-Sphere M-60 Mono blocks OTL design


I just purchased a used OTL Atma-Sphere M-60 mono blocks that I have sent to Atma-Sphere to be upgraded to the current model 3.3 and I also added the option of a higher quality power supply and V caps.

I have sold my old trusted Eggleston Andra 2’s speakers and have built some monitors using Aurum Cantus ribbons (102db) and Aurum Cantus midwoofers (90db) that are both rated as 8 ohm nominal. I have a DEQX Premate and will be crossing over to (2) JL Audio F-113 subs at 80hz.

Currently I am using a solid state high power stereo amp (Pass Labs) that I used with the Andra 2’s.

The Atma-Sphere M-60 is rated at 60 watts class A and is said to work better with higher impedance loads.

It will probably be a few weeks until I get the M-60 and was hoping someone could provide opinions of what to expect.

I listen to late 60 early 70’s classic rock music mostly. Sometimes loud.

ozzy

128x128ozzy
ozzy- FWIW, mine are too, although to be correct, they are DIS...do-it-someone else ;-).  The S-30 drives Feastrex quasi-full range field coils, reportedly about 94dB, crossed over at about 60 hZ to a Class D Crown for the low end.   So it is an easy load.  When I had the M-60s, I was using Merlin VSM-MMs. 
Ozzy,
You're moving from very high power transistors to moderate power OTL with very high quality part upgrades. Keep us posted on this quite interesting comparison. I'm curious about what contrast you may hear.
Charles

swampwalker,

I would have thought that the Merlin's would have worked well. I will be using (2) JL Audio F-113 subs crossed over at about 80hz.

charles1dad,

I know what you mean. Just to keep everything fair, I bought another (same) power cord, another amp stand (Grand Prix) then I had to buy new isolation pads for the stands for the lighter load.

ozzy


I have a pair of original Atma-Sphere Z-Music Transformers, if you or anyone else needs them. They will change the output impedance to whatever you need it to be for your speakers.

Thanks.

Elliot
Ozzy- It was my bad; I was seduced by the warmer sound of a Joule-Electra VZN-80 but once I went to a better pre, I regretted it.  Eventually sold the Joule amp, too.