29/07/2015-19:15:26
RE: Amplis Aleph simu tests
....I've heard John Curl say it, I've heard other designers say it...Well, 10:1 is pretty good. That sort of thinking was being used also when people were dealing in slew rate.
A 1000V/µs slew rate was, at one time, obviously state-of-the-art, but it was also being touted as "you need this!"
....
On record ticks and pops I could register slew rates as high as 20–30V/µs—real signals that were being processed through the differentiating network and then onto a storage 'scope. So it came time to play some music. Again, if you clipped the amplifier you could see 40 and 50V/µs recovery; that is to say, the amplifier, in catching up from clipping to get to where the signal was, would travel that fast to catch up. So clearly the system—the amplifier and the measuring system—were capable of resolving 40 and 50V/µs transients. In playing music we were looking at piano, cymbals, violins—a large range of instruments all played loud, near the power capacity of the amplifier. And we were getting values like 0.1V/µs, 0.5V/µs. In fact, at that time in that series of tests, the highest transient we were able to achieve was about 1V/µs. So the 10:1 ratio would dictate that you would need at least 10V/µs performance.
http://www.stereophile.com/content/nelso...z4K93yC.97
A 1000V/µs slew rate was, at one time, obviously state-of-the-art, but it was also being touted as "you need this!"
....
On record ticks and pops I could register slew rates as high as 20–30V/µs—real signals that were being processed through the differentiating network and then onto a storage 'scope. So it came time to play some music. Again, if you clipped the amplifier you could see 40 and 50V/µs recovery; that is to say, the amplifier, in catching up from clipping to get to where the signal was, would travel that fast to catch up. So clearly the system—the amplifier and the measuring system—were capable of resolving 40 and 50V/µs transients. In playing music we were looking at piano, cymbals, violins—a large range of instruments all played loud, near the power capacity of the amplifier. And we were getting values like 0.1V/µs, 0.5V/µs. In fact, at that time in that series of tests, the highest transient we were able to achieve was about 1V/µs. So the 10:1 ratio would dictate that you would need at least 10V/µs performance.
http://www.stereophile.com/content/nelso...z4K93yC.97