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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's avatar
ozzy OP
7,542 posts
 

Ok, after about a day of use, this is what I just emailed Ralph.

Ralph,

I am using a DEQX preamp unit.

Along with preamp functions it has an electronic crossover. It measures the speakers, subs and then the room. You don't have to perform any EQ function.

I was amazed at how very flat my DIY satellites measured! Never, have I seen that type of flatness before with the Pass Labs amp!

More to follow.

ozzy

rfogel8's avatar
rfogel8
192 posts
 
Ralph, I stand corrected. I saw a photo of the MP-1 3.3 on "What's Best Forum" and as the saying goes, sometimes we look but don't see. Three 6SN7's and five 12AT7's per side. As usual, the layout looks meticulous.

I assume the front 6SN7 nearest the faceplate still has the most effect when tube rolling? 

Glad you're doing well Charles and still listening regularly. I see Fremer was in town recently and spent some listening time at Jeff's. We should get together soon and spin some tunes. You still running all Coincident? I thoroughly enjoyed that evening listening to your Frankenstein's. At only 8 watts and as loud as I cranked them up at times, I couldn't believe they never clipped. I see why 300b's have such a loyal following. I'd love to hear what Blume could do with 845 monos. I wouldn't give up my MA-1's but variety is the spice......



gdnrbob
4,460 posts
 
Ozzy, do you have any pics of your speakers?
B
charles1dad's avatar
charles1dad
10,250 posts
 
Bob,
Fremer spent about 3 hours at Jeff's listening and they had a good time. Yes I'm still full Coincident, just as you're Atma-Sphere. we're both quite happy so why change?  By the way Israel (Coincident)  will be debuting 845 SET mono blocks in the near future.  I'm all for getting together for some listening, its been awhile.
Charles
atmasphere's avatar
atmasphere
11,963 posts
 
As usual, the layout looks meticulous.

I assume the front 6SN7 nearest the faceplate still has the most effect when tube rolling?
Yes.

It seems to sound a lot better too. In particular the phono has more gain and less noise. My workers take a lot of pride in their work and usually sign the equipment after its done.
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