Some thoughts about reliability and feeding tubes to an OTL faster than spark plugs to a Hemi...
I would be out of line to speak about amplifiers other than the AtmaSphere M60, but I can tell you I have nothing but the utmost respect for what Ralph Karsten has designed.
I have to say that when he says his amps are all but bulletproof, BELIEVE HIM! The literature states that pretty much no matter what goes on, it will not take the amp or your speakers out. That's a fact. It may cost you a couple of fuses while you are learning about biasing, "zero offset", or not shorting the amp, but that's about the worst of it.
As to tube longevity, the prototype of the AtmaSphere M60 is supposedly still running its original set of tubes - 20 years later! I kind of stupidly used one suspect tube(thanks Sovtek...). It was fine for a while, just had a permanent bolt of lightning out to the glass, and pulsated strongly with the music. But, when I ran another pair of amps for 2 months, and put them back into service, that tube just didn't feel like being social. It did all kinds of misbehaving, time after time. And despite some really awful pops and bangs, true to Ralph's word, the tube's pyrotechnics didn't harm my amp or loudspeakr in the slightest - try that with a Futterman. Other than seeing this kind of once in a while Soviet QA, the 6AS7G tubes last a long, long time.
I would be out of line to speak about amplifiers other than the AtmaSphere M60, but I can tell you I have nothing but the utmost respect for what Ralph Karsten has designed.
I have to say that when he says his amps are all but bulletproof, BELIEVE HIM! The literature states that pretty much no matter what goes on, it will not take the amp or your speakers out. That's a fact. It may cost you a couple of fuses while you are learning about biasing, "zero offset", or not shorting the amp, but that's about the worst of it.
As to tube longevity, the prototype of the AtmaSphere M60 is supposedly still running its original set of tubes - 20 years later! I kind of stupidly used one suspect tube(thanks Sovtek...). It was fine for a while, just had a permanent bolt of lightning out to the glass, and pulsated strongly with the music. But, when I ran another pair of amps for 2 months, and put them back into service, that tube just didn't feel like being social. It did all kinds of misbehaving, time after time. And despite some really awful pops and bangs, true to Ralph's word, the tube's pyrotechnics didn't harm my amp or loudspeakr in the slightest - try that with a Futterman. Other than seeing this kind of once in a while Soviet QA, the 6AS7G tubes last a long, long time.