2. amps-preamps
  3. 128359-41

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
 

almarg,

I have noticed a very low level hum when I place my ear up to the speakers with no music playing. But, it is minimal and I overall prefer the sound quality over that minor annoyance. Perhaps if they are installed in a preamp it may cause more problems downstream.

charles1dad,

How does Sophia get there brand on the tubes if they select the best ones? I think they just purchase a lot of the tubes from TJ and have them branded "Sophia" then they grade them A-C. I think the grade A ones are used in the USA market and sold direct from within the USA.

ozzy

charles1dad's avatar
charles1dad
10,250 posts
 
Agree that’s there’s some method of selecting/rejecting tubes from the original vendor TJ Full Music. I was just making the point that they’re re-branded tubes under the Sophia name.
Charles
gdnrbob
4,460 posts
 
As this is my first Tube Amp and Preamp, I have no idea who sells these, nor who is a good source. So, where do you guys get these tubes?
Bob
charles1dad's avatar
charles1dad
10,250 posts
 
Sophia Electric. com, their own site.

TJ Full Music tubes
1  DIY HIFI Supply
2  tubes-sale.com
3  Grant Fidelity. com
Charles 
ozzy's avatar
ozzy OP
7,542 posts
 

I bought mine off EBay.

ozzy

More to discover