Both times I have heard Atmasphere amps at shows, they were used with very large, very expensive high efficiency speakers from Classic Audio Reproductions.
First time in a small hotel room where the whole system was just a lot of overkill, more recently in a larger hotel ballroom where the gear had a chance to truly show what it can do and did it well.
I would like to hear the Atmasphere amps used with smaller high quality speakers that would tend to fit and work better in most peoples homes.
I have no doubt the results would also be quite top notch but the thing I wonder is if the results would be as "special" compared to others. I think of the Atmasphere products as very unique and special, not "weird", though they may look it to some.
IMHO, you have to really be a tube lover for whatever reason to live with any larger tube power amp with many tubes. TCO will be high due to power consumption and maintenance of tubes to keep things in peak operating order compared to other options ie SS.
High quality modern Class D amps of recent years are game changers IMHO. Not that they sound like many tube amps, but they do share some sonic qualities, are much smaller, have low maintenance and likely lower overall TCO (total cost of ownership) due to high efficiency, low power consumption, and no tube maintenance.
I use a tube pre-amp with 6 tubes with a Class D amp. I find this to deliver the kind of sound many tube amp lovers might enjoy with minimal use of tubes. Tube pre-amps are much more easily managed than high power tube power amps. I’d like to have no tubes eventually and am working towards that. My second system uses a true digital Class D integrated amp. The sound is quite excellent I think but will not be every tube amp lovers cup of tea for sure. I find this amp makes good quality dynamic box speakers sound like electrostats along the line of ML or Quad, but with better dynamics. I am using it currently with a pair of Dynaudio Contour monitors. Its a very interesting phenomena to hear how radically different the Dynaudios can sound in two different systems.
Also on my bucket list is to put together a third system built around a small tube integrated amp and high efficiency speakers. I enjoy putting together good sound in different ways, and on a small scale, tube gear is much easier to live with.
