Low dist at high frequencies

[Pan]

How low distortion are we able to get in the top octaves from a power amps these days?

Or like this;

What amps on the market has the lowest distortion at the top octaves?

Lots of amps have like 0.005% THD or so in the 100Hz-1k range but usually much higher numbers above that. Are there any real performers out there with less than 0.01% at 20k for example?

I believe Halcro and Dynamic Precision has ultra low dist, but how about those high frequncies..?

/Peter

[darkfenriz]

what is the purpose of measuring harmonic distortion of 20kHz as the harmonics (40kHz, 60kHz...) are far beyond human's ear hearing range. I guess neither dogs nor bats don't mind some distortion.
but seriously, this is a good question, but even ,say 4kHz harmonics may be hardly detectable
cheers

[Pan]

The thing is that many amps begins to suffer from increased disotrtion at 1k or so, indicating problems with fast signals. IME the highs are among the parameters that has most difference sonically among amps.

Since new amps (power as well as ICs) with really low dist. in the mids has entered the market and often sound extremly good, I simply would like to find out if it´s worthwhile to have equally good behaviour in all of the audible range.

Typically FET amps have a rise in dist. at 1k.. this is true for class D amps as well. The most linear amps distortion vs. frequency sems to be BJT amps, they can have similar numbers up to 100k or so before the dist. rise significantly. However the amp I am thinking about do not have ultra low distortion like some other amps have in the low range (sub 1k).

/Peter

[Upupa Epops]

Best amps of these days have distortion 0.001 in all acoustic band and curve of distortion is very flat, rise practicaly only above 100 kHz . But to make it is not easy, because all constuction must be perfect in every details. By the way, price is adequate, look at Halcro or Dynamic Precision .