tube Watts vs solid state Watts

When comparing two amps, I think the power rating is the power rating - no matter whether Class A or B as long as you are comparing at the same THD. Perhaps the discrepancy is due to type of distortion as mentioned above because Class A and Class B definitely have different distortion characterisitics. But I also feel (and this applies to tube amps too) that tonality can play a role. I often hear that such-and-such low-power tube amp has better bass than some big SS amps does and that gives the impression of more power.

Another thing I have heard a few times now is that tubes are able to produce a huge amount of power for a very short amount of time - much moreso than SS amps can. I am not sure about the validity of this claim but from a signal level conduction resistance point of view, it makes sense since you are comparing vacuum with "sand."

But when you are dealing with human perception, everything gets cloudy. Everyone is entitled to their opinion so take what you hear and read with a grain of salt but don't get upset by it. :)

Arthur

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.

A Watt is a Watt.. No doubt.. This might be slightly off topic,
However I have 20 watt tube monos that Shocked the H3LL out of me, that put out more clean power and musical response than 200 watt SS monos that by the way costed in the 4 k range. Tube power is very different regardless how many here want to say its the same.. it is on paper but seems to be very different in actual use..

Another example is why would a 50 watt Marshall Guitar head amp just need 50 watts to go into concert levels? Yes a big reason is the far more efficient drivers, and the limited frequency range being not too deep of bass taxing the amp, but fact is I would still take a 50 watt marshall over a 300 watt peavy SS and walk all over it!

So don't be afraid of low power Class A tubes, they still pull way less power from the outlet than a 200 watt boat anchor like a adcom or mcintosh that dims the lights in the house when turned on, just make sure you have efficient speakers and it will not matter. Don't get me wrong I have had great amps from both camps, but low powered tubes are probably much more impressive on first listen due to very little power and big sound, vs. many solid state amps seeming to be fairly closed in and restricted regardless of power ratings. Just another partial audio mystery to most, and even urban legends that small tubes can't produce acoustical power, mostly they do more so until you get into some really serious solid state stuff.

Undertow: what is your explanation for these a bit counter intuitive findings? So those people who say that tube Watts and solid state Watts are not alike should be taken seriously?

Chris

Dazzdax, simply put I think it has to do with a
200 watt SS will put out about 10 watts of good power at lower levels, and it is not continously putting out 200 watts at all gain levels. It switches into this high wattage in peaks..

Class A tubes are running 100% at output at all times, same temperature, same stress, same outlet power draw etc...

When a SS hits it then taxes your power system in the house very quickly and can sound less impactful for the instantaneous peaks they actually perform on and off.. Tubes seem to be much more "Consistant" watts..

But measurably I am sure both would say the same on a meteer, but two totally different devices deriving these watts.