amplifierguru said:
Yeah, it's pretty desperate
. Its the gain that determines the loudness level at a given input level (assuming same speakers of course). So, same gain, same loudness. What would be different with a high power amp is that it will clip at higher input levels. But, since the question was "at low levels" that doesn't appear to be a point.Jan Didden
tlf9999 said:
This is simply not true. SR is DEFINED as the rate of change of output voltage per unit of time, like in Volts/uSec. That is determined by the amp topology, the compensation, the used devices etc.
A higher power amp would REQUIRE a higher SR if it has to reproduce 20kHz at full power, and a lower power amp can get away with lower SR to reproduce those 20kHz at lower power. After all, it need to swing less output voltage in the same time (the 20kHz period). BUT, most amps have SR that is waaaay beyond what is required. And also, you can easily have a low power amp with 50V/uS SR, and a high power amp with 20V/uS slew rate.
In fact, because the higher power devices used in a high power amp are generally slower than low power devices, I would EXPECT that a high power amp has LESS slew rate than a low power amp.
You CANNOT say that a high power amp by definition has higher SR, because it is not true.
Of course, you can say a COMPETENTLY designed high power amp has higher SR. That is technically true, but it ONLY means that it has the SR to give undistorted output at full power. But that low power amp also gives undistorted with its lower SR. So, the sound would not be different because of the different SR.
It all says one thing: saying that a high power amp sounds better because of higher SR is nonsense.
Jan Didden
As I said -
"I'll stick with my original theory that it's the better power supply of a larger amp. It's reasonably to expect a designer to allocate sufficient power supply capacitance to keep ripple low (say 1V) at maximum power, so a high power amplifier will have a higher C by 2 or maybe 3 times AND a lower Z transformer (150VA typ 10% regulation, 500VA typ 3%). Given the commutation artefacts
due to class AB - spray of harmonics AND the emphasis of these at 6 dB /octave by the typical declining PSRR of a conventional miller compensated design, I'd say I'm right on target."
If that wasn't topology related I don't know how to say it in words of one syllable.
R.I.P.
"I'll stick with my original theory that it's the better power supply of a larger amp. It's reasonably to expect a designer to allocate sufficient power supply capacitance to keep ripple low (say 1V) at maximum power, so a high power amplifier will have a higher C by 2 or maybe 3 times AND a lower Z transformer (150VA typ 10% regulation, 500VA typ 3%). Given the commutation artefacts
due to class AB - spray of harmonics AND the emphasis of these at 6 dB /octave by the typical declining PSRR of a conventional miller compensated design, I'd say I'm right on target."
If that wasn't topology related I don't know how to say it in words of one syllable.
R.I.P.
Hi Greg,
Soooo, if we take an iffy amp and put a really good power supply on it, it will sound great? I have some Nikko's to improve!
I'm not trying to be silly, but I think I'm missing your point entirely. My belief is that you can destroy a good amp with a bad power supply, not the reverse.
-Chris
Soooo, if we take an iffy amp and put a really good power supply on it, it will sound great? I have some Nikko's to improve!
I'm not trying to be silly, but I think I'm missing your point entirely. My belief is that you can destroy a good amp with a bad power supply, not the reverse.
-Chris
amplifierguru said:Hi jannerman,
Yes I said it was desperate - because I was assuming a very naive listener would use a fixed input level not knowing the higher gain of the big amp - and being impressed!
By the extra power.
Cheers,
Greg
Quite right. The original poster is conspicuously absent, as has been noted. He must be leaning back enjoying the show.
Jan Didden
janneman said:
so to output more power, don't need to output more voltage (higher voltage swing). Doesn't that give higher SR in a given period of time?
janneman said:
if we aren't considering competently designed amps, we will run into tons of weird possibilities then the whole discussion is meaningless.
janneman said:
the lower powered amp will do so only at lower output levels. In otherwords, at the same output levels, the higher powered amp is capable of following faster signals -> better bandwidth if you will.
anatech said:
Not necessarily great, but better. We did a fair amount of that with NAD 3020s & Haflers back in the day when they were new.
In modern day, the chip-amp is a good example. Bigger, better regulated trafos, better rectifier diodes, higher quality smoothing caps, & regulation all make a big difference in amp quality.
dave
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.