"Fast amps" - really fast or a bogus marketing claim?

[caesar]

Some brands claim their amps are "fast". I'm thinking Goldman and Spectral. What is a fast amp? Or is it just marketing BS?

[AudioExplorations]

Interesting question.

[joeinid]

Interesting question.

+1

Is faster necessarily better?

[docvale]

If I'm not wrong the definition of speed of a power amp is related to the slew rate.

[Gregadd]

Many people get confused by the term "speed." Remember amps must resct to thier input,

Spectral gve s this spec for thei amp:
Speed:
Risetime: less than 300 nanoseconds
Settling: 1.5 microseconds to -40 dB
Slew Rate: 600 volts/microsecond

[lloydelee21]

+1

Is faster necessarily better?

I have read a review of the Berning Quadrature Z monoblocks by 2 different editors of HiFi+...one of them wrote something like "i have never heard anyone complain about an amp being too fast." I think the point he was making was that the amp's job is simply to pass along the signal coming thru...with no way to speed up the music, make rim shots faster...he was basically suggesting that speed was one factor that allowed for transparency. What comes in...goes straight out without delay.

I think, in isolation, that concept makes sense to me. Obviously, there can be side effects in trying to design equipment to do this which might be deleterious, but i cannot imagine this one aspect alone can be bad. And i could imagine that this one aspect should be better...all else being equal.

[joeinid]

Makes sense, thanks for the explanation Lloyd!

[MylesBAstor]

I have read a review of the Berning Quadrature Z monoblocks by 2 different editors of HiFi+...one of them wrote something like "i have never heard anyone complain about an amp being too fast." I think the point he was making was that the amp's job is simply to pass along the signal coming thru...with no way to speed up the music, make rim shots faster...he was basically suggesting that speed was one factor that allowed for transparency. What comes in...goes straight out without delay.

I think, in isolation, that concept makes sense to me. Obviously, there can be side effects in trying to design equipment to do this which might be deleterious, but i cannot imagine this one aspect alone can be bad. And i could imagine that this one aspect should be better...all else being equal.

Not sure that I'd agree. Remember the adage speed kills . Years ago was talking to Dan D'Agostino about that subject and he told me that he could and had designed ultra fast circuits but you woudn't want to hear them

So maybe those ultra fast designs were eliminated in the design stages and never saw the light of the day.

[Mike Lavigne]

i thought i knew what a fast amp sounded like.

then i listened to a 45 tube and then 2a3 tube both with mercury tube rectification. there are plenty of things those amps can't do. but the speed inside the note was a whole different thing than anything else i have heard. other tube amps i've heard were not like those two at all. and the best solid state amps i've heard can't quite do that either. the 45 tube was even slightly better than the 2a3 at this. a simply un-veiled window into the music....on a micro level.

too bad i'm not enamored by speakers that work on those types of amps.

[lloydelee21]

Not sure that I'd agree. Remember the adage speed kills . Years ago was talking to Dan D'Agostino about that subject and he told me that he could and had designed ultra fast circuits but you woudn't want to hear them

So maybe those ultra fast designs were eliminated in the design stages and never saw the light of the day.

Hi Myles...i do think speed in and of itself is a good thing...but i think that sometimes (perhaps often) the path to get there comes with "side effects" or other unwanted aberrations. Lack of depth or tone of the note is one...even the Berning supposedly lacked just that teeny bit of depth of note...slightly shallow. But again, that is not the speed, but the unwanted side effect of the speed which is that the unit cannot be that fast and also provide the full depth of note. (personally, i'd take the depth of note a give up a little speed).