Power output of tube amps compared to solid states

Acrossley; Just to chime in, power is power period. and power is defined as IxIxR or VxV/R or VxI. In any case, power is related to resistance only. But speaker loads are not only made up by resistance only but what is called impedance that includes resistive loads and inductive loads and capacitive loads. So, when you see an amp spec'd at 50 wpc into 8 ohms, the manufacturer is stating clearly that this amp will produce 50 wpc from a particular input voltage (input sensitivity) into an 8 ohm resistive load. If they wanted to be clearer they would tell you what the power output is into an impedance (R+L+C) load at particular frequencies. but they will not do that. So, basically, what is on the amp specs is not what is really happening because your speakers are not resistive loads. So you are comparing apples to oranges. another example would be to take two 50 wpc into 8 ohm amps. One tubed and one ss. They both have a particular input sensitivity which will drive an 8 ohm resistive load at 50 wpc and typically that is measured with an input signal of 1khz. But, make that load a reactive (resistive, inductive and capacitive) load at 1khz at the same input signal level and you have an entirely different story. Or lower or increase the frequency with the same input signal level and no way will you see 50 wpc, unless you have a very well designed and built amp and let me tell you, you will pay a lot for that amp. Because it was designed and built correctly. I hope I didn't glaze your eyes. but every 50 wpc rated amp cannot drive the same loads the same because they were not designed to. The specs presented do not tell you everything. But, my point (long as it is) is that 50 wpc into 8 ohms resistive is the same, no matter what amp we are talking about. But the real loads your amps see are definitely not resistive and therefore the 50 wpc into 8 ohm spec goes out the window.

enjoy

Interesting conversations. The original conversations changed from the definition of power to sound quality of tube vs. solid state amps. There is an amazing bias here between the tube lovers and solid state lovers and music lovers. Personally, if the music doesn't sound real, then I couldn't care less if it is solid state or tube. Same logic applies if the sound drives me out of the room. As I mentioned previously, quality designed tube or solid state amps would reproduce the signal accurately and both sound wonderful. Speakers have various impedances and some are easlier to drive than others and that really affects whether the amps would work well or not. There are many various criteria for amp design. Imput impedance, gain, output impedance, current capacity, voltage, power output into specific loads, etc. All of these criteria can help determine if the design and construction and parts used should be of higher quality or not. Some times, more than not, you really do get what you pay for. All that said, I have listened to some wonderful tube equipment and also have listened to some equally wonderful solid state equipment. Nothing is perfect yet. it would be hard to design and build perfect. First, you have to assume that the music was recorded 100% correctly, using equally great recording equipment and that just simply is not the case. Maybe with Mark Levinson or Manley recording gear, but in most cases, the music isn't recorded perfectly from the beginning. Then send the signal from a source (album or cd or tape) to your preamp. Well, the cables have impedance don't forget and will slightly degrade the signal, unless corrected for. the pre-amp will degrade the signal. not one is perfect. The cables from the pre-amp to the amp degrade the signal. The amp will degrade and the speakers aren't perfect in reproducing signals either. See where I'm going? At this point in our scientific history, we aren't there yet. Electricity over wires and through tubes, resistors, inductors, capacitors, transformers, etc. will produce distortions and have losses. Can't get around it. Can a tube amp beat a solid state amp? absolutely, same can be said visa versa. How were they designed and built? Were they designed and built on the same price point? power output?, etc. if not, you are comparing apples to oranges.

I love good, accurately reproduced music and couln'd care less if it came from tubes or solid state. If it is right, then it is right.

enjoy