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
Glad that the Full Music 6SN7s worked out well for you, Ozzy. Your findings regarding their excellent sonics are consistent with many others I’ve seen reported for their Sophia counterpart. Including feedback Ralph mentioned earlier in this thread that he has received from a number of customers. However, I’ll note for the record and for the information of those reading this thread that at various times in the past I and at least two other members here experienced totally unacceptable hum problems with the Sophia version of the tube. See my posts dated 4-2-2017 in this thread, and the link provided therein, and also the post in that thread dated 4-3-2017 by Tubegroover. It can be expected that sensitivity of preamp and power amp designs to what I determined was apparently the cause of the problem (measurably excessive heater-to-cathode leakage, resulting from either a design defect in the tube or a quality control problem in its production) will vary widely among different designs. I would suspect that some designs will be totally insensitive to it. And FWIW, apart from the hum issue the Sophias did sound great in my amp. Best regards, -- Al |
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 |
