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I remember hearing a while back that tube power amplifiers can sustain longer bursts of instantaneous power than solid state amplifiers. This aspect seems to relate to the perception that tube watts are 'bigger' than SS watts.Is there truth to this? I am asking because it is a constant source of contention (I intend no contention with this question!) that even with high efficiency speakers a person would need 100 watts of power to handle the 'musical peaks' or else suffer 'compression'.
Can anyone explain this for the completely pea-brained(me)?
Follow Ups:
halley
As big a tube aficianado that I am,Im not sure that holds true as far as electrical reality goes..Typically your SS amps today are regulated B+ and that helps maintain a constant supply to your output devices under most any transient conditions and therefore should maintain full and peak power most of the time as long as you dont go into saturation beyond rated spec.
Then again if your talking about a tube amp with regulation,it also maintains its power under most conditions and like the other posters said the distortion is more pleasing from a tube than a SS amp becuase of the type and small amounts of even order distortion tricks the mind into thinking the amp is playing much louder when in reality it probably isnt..The question you ask is subjective and it really depends on the amp class and power and conditions so its all realitive..
When tubes are overdriven, they gradually clip; that is, they provide progressively less response for added input, kind of like a spring being overextended. When a transistor is overdriven, it just stops addding any further response; that's called hard clipping, and it sounds horrible. Tube clipping sounds nowhere near as bad as transistor clipping, and is thought to be why a tube watt sounds more powerful than a transistor watt. The instantaneous and sustained power issue that you mention I think would have more to do with power supply impedance and heating of solid state output devices.
In addition to softer clipping, tube amplifiers usually clip as a result of the power tube grids being overdriven. This causes asymmetrical, even-order distortion. In small amounts, <5% or so, such distortion causes an amplifier to sound louder to the human ear. Transistor amplifiers, on the other hand, usually clip because the output devices have reached the power supply "rails." This causes hard, symmetrical clipping and generates an abundance of odd-order spectra. It does not sound louder, only harsher.
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