Carver 275 Crimson tube amp --- any feedback appreciated

The tubes in the Crimson 275 are warranted for five years. Our competitors give three months. Prima Luna, an excellent product, gives six months. The tube checker is built into the amplifier. You can check your neighbors' tubes at full operating parameters. We've given out between three and 10 tubes in the last 10 years depending on who you speak to.  On this model tube life would be about 20 years. It's even greater on our more expensive amplifiers (and their extended warranties reflect this) but we run the KT 120s a bit harder in order to come up with 90 W per channel which every 275 is capable of. We have no service department because we have no failures. The 275, like all of our amplifiers, repairs defective tubes if the malady, the most common, is caused by impurities. We vaporize the impurity, sacrifice a dedicated fuse, and you're back in business.
Frank Malitz CEO
The Bob Carver company 

Frank,
Thank you for the information.  I am not sure that I need to check my "neighbor's tubes", but that is an intriguing idea.   It is evident that the amp runs in such a fashion to ensure long life to its tubes, which is are major factor in my decision to buy one.  

I have never heard of a process to "repair" defective tubes.  If you have such a process, I have about 60 rare NOS tubes that would be happy to see renovated to their former performance if you can do that.  I am keen to hear some reports of folks that are using the 275 amp in their system.  

I’d be curious about the Low end (bass) of the 275 when mated with very efficient speakers like my Zu Omen defs. My biggest hesitation on trying avtube amp is lack of bottom end. I really like deep bass

Like most tube amps, higher impedance speakers are better matched to Don's amp. If your speakers dip below, let's say, 4 ohms, then I think it would not be the best match.  With my 12 ohm Spatial Audio speakers, the bass is reproduced extremely well, pretty much as well as with my 100 wpc McCormack amp.  To my mind, that is a huge accomplishment because I have never experienced such low end response in a tube amp as I have with Don's amp. 

The question to ponder is whether or not your   Spatial Audio Hologram M4 Triode Master speakers need an amp with high current output and control that SS offers. Like your DNA-0.5. If they do, the Carver will certainly fall short. I tried driving my restored, very current hungry German Physiks Borderland MK1 with my Carver VTA180M Cherry monoblocks, and it was dull and lifeless. I took a shot and bought a McCormack DNA 1.0 with rev B upgrades and the GP's came alive. Was so happy with the synergy that I sent the amp to Steve for a full upgrade including the Plitron transformer. The Cherry's went back to my vinyl rig. I'm thinking the best attribute about the Cherry's  driving my Legacy Focus SE's was that they were dead quiet and run super cool. Carver lifts the grounds by using only a two prong plug. And although the focus SE's are very sensitive, as far as the mid-bass and low end bass is concerned, the Cherry's "just run out of iron" and the mid range is somewhat smeared and lacks detail. The highs are just OK. Now that's MY system. YMMV. Well the itch came back, and decided to sell the Cherry's, and they will be replaced with a Wells Audio Innamorata. My front end remains tube though, and its going to be an interesting experiment driving the Wells with a Dehavilland UV3 and Fosgate Signature phono stage front end. When using the Carvers, of course go by what your ears say, and not the published specs, because Carver tends to always "exaggerate" his performance specs.