tube Watts vs solid state Watts

In a tube amp there is (usually) an output transformer, and it, as much as the power supply or tubes, will limit the distortion-free power output of the amp. The real heart of a tube amp is its transformer. Good ones are few which is why OTL amps exist.

Not all ss amps clip harshly, if at all. My CarverPro ZR1600 have clip detection and automatic gain reduction if clipping occurs. I have never seen the CLIP LED illuminate. However, in home audio application this is probably the usual case as the darned thing is rated at 600 watts into 4 ohms.

I took the trouble to actually measure the voltage being applied to my 4 ohm MG 1.6 speakers by my 600 watt amps during peak volume intervals of VERY loudly played music. I wanted to know if a lower powered amp would be OK. Most of the time the maximum rms voltage over a brief (1 second) interval was 10 volts or less, which correspionds to 25 watts. (At times when the music was quiet the voltage was only a couple of volts, which is one watt). However, there were a few moments when I saw about 40 volts and this would correspond to 400 watts. A 40 volt rms sine wave would have instantaneous voltage peaks of 56 volts. Since the CLIP LEDs did not illuminate I guess that my amp was able to follow a 56 volt peak waveform,

So, I concluded that 600 watts is not as much of an overkill as you might suppose. Nevertheless, because this test was done with music much louder than I would actually use I bought some new amps which are only(!) 350 watts into 4 ohms, and they are OK. (I did not buy some 60 watt tube amps which I had been considering). In general, my experience has been that every time my amp power has been increased the speakers sounded better. I think that high powered amps have characteristics other than their maximum power capability which are helpful.