differences between tube and solid state designs

"I suspect that some of the low-level articulation advantages attributed to high efficiency speakers is due to their typically being driven by Class A amplifiers which have no crossover distortion]."

The sensitivity/efficiency measurement of speakers is an expression of output sound level for a given input voltage. I am betting that the reason high efficiency speakers "articulate" better at lower levels is that the volume is actually louder at the same dial setting that you used for the less efficent speaker. Unless you have guaranteed that the sound pressure in the room is exactly the same for both tests, it's hard for me to swallow that crossover distortion in a modern class AB amp is to blame.

"Single-ended and OTL tube amps do not suffer from this effect, known as hysteresis."

All magnets suffer hysteresis losses. This includes transformers. OTL amplifiers parallel a bunch of tubes to get the output impedance low enough that a transformer is not required, but every single ended tube power amp I have ever seen has one.

And you determined these amps that you were listening to were clipping how, exactly? I constantly hear this stuff on these groups, hard vs soft clipping, even vs odd harmonics, class A vs class AB, tubes are valves and transisters are switches, etc.

You want to know why tube amps sound different than SS amps? All you have to do is look at the frequency response graphs published in every Stereophile review and look at the trace using the simulated speaker load. The amplifier's output impedance is basically in series with the speaker load. A tube amp's impedance is so high that it creates a divider network consisting of itself and the speaker load.

Tubes - Big humps at 65-70 HZ and 1.5 KHZ, big dips in the mid bass and treble, dropping sharply after 10 KHZ.

SS - Flat.

"SS - Flat"

Couldn't have said it better myself. I've always found SS amps to sound flat.

Sorry, couldn't resist. :-)

I've always found SS amps to sound flat.

Newbee (System | Threads | Answers)

You beat me to it.

:)

Keneallyfan,

What you point out also explains the fascination with cables more often found with tubed gear...of course with a high output impedance even the speaker cables begin to play a role in modifying the sound coloration...

SS amps tend to be flatter in their frequency response when coupled with a speaker - no question about this - SS gear wins hands down!

For those who prefer tube coloration there are other options such as an EQ, however, a tube will also clip nicely producing pleasant harmonics which is another feature that tubers love and which only a tube EQ could deliver. (no real SS alternative for creating that tube sound...at least not widely available yet)

One of the world's top mastering engineers uses a set of tube gear designed by his brother to add a bit of warmth or tube sound to lean mixes....this engineer has a veritable list of who's who that use him. So I am not knocking tubes in anyway, besides for those who play electric guitar....tubes are absolutely essential for the type of distortion they create.