Atma-Sphere M60 or David Berning ZH270?


Hi, I need some helps to decide which one of these two amplifiers to go with my 14ohm Coincident Super Eclipse (SE).

The Atma-Sphere seems a perfect match for the SE at least in impedance matching and at 14ohm, may get more power than 60 watts. The ZH270 may get less than 70 watts @14ohm. However, I have the following concerns for the M60:

1. 8 6AS7 output tubes per side generates a lot of heat and it does not have cage protection. This is quite a problem if you have young children at home like me. The ZH270 has tubes internal (like a Tube preamplifier) and thus safer for young children.

2. 16 6AS7, though last long time, can be more expensive than ZH270's 4 6JN6 if I try to replace them.

Pro for ZH270 can run without a preamp and is auto-biasing.

On the other hand, ZH270 is more expensive ($4995) than M60 MKII.2 ($4250) (current still have a few left).

As far as the most important factor: sound? I have no idea at all. I have not heard either one anywhere. I have owned ASL Hurricane for over a year and like the sound very much but disappointed for the constant re-biasing and QC problem.

Does any one have Reliability problem with either one?

My listening room is 13Wx8Hx26L and I listen almost only classical music from solo violin, piano, to chamber music to 20 century's big symphony orchestra works (Mahler, Strauss, Stravinsky, etc.).

Thanks for the helps.
laoyuap

Showing 1 response by mwl168

Just my 2-cent as an Atma-Sphere owner. Unfortunately I have no experience with the Berning amp.
I put a pair of M60 MK2.2 into my system this past July and in a matter of days decided to sell my Krell monoblocks that I have happily lived with for more than 10 years.
To my ears the AM is simply "truer" and "righter" than anything else I have listened to as far as timber accuracy and tonal balance go. It has none of the problems I've heard from other tube amps possibly in part due to AM's elimination of output transformer. Both extreme ends of audio spectrum are well extended and defined, sound stage and imaging is also as good as any I've heard. This all from pairing it with a pair of less than ideal speaker with a nominal 4-ohm impedance.
The reliability has not been an issue. It never missed a bit from day one.
There is also something to be said about the benefit of completly point-to-point wiring without the use of PCB. This also opens up the opportunity for future tweaking and upgrading if you are into the sort of things.
I like it so much that I am actually in a process of getting a pair of MA-1 Silver to better match my speakers.
Hope this helps! Best of luck and happy listening!