Bob Carver accepted the amplifier challenge from Stereophile, many years ago, and won. He showed that he could duplicate the sound of an expensive amplifier chosen by Stereophile with one of his amplifiers appropriately modified to sound the same. The staff of Stereophile could not identify any difference by extended listening tests over a couple of days. Bob didn't use a trial-and-error method and judge by listening to achieve his win. He used what he knew from experience and from scientific principles.
Bob used his extensive knowledge and experience in amplifier design to duplicate the transfer function of the expensive amp in his amplifier, to a sufficiently high degree to win the challenge. The "transfer function" is well-known to scientists and engineers.
He also knew that if a difference between the two amplifiers is made sufficiently low to be inaudible by human ears, then the listeners could not identify any difference between the two amps. He used science and knowledge of human hearing, thresholds of hearing.
@Millercarbon said it first in this thread, that science is a method. Bob used the scientific method, and technology by measurements of the amplifier to make both amplifiers sound indistinguishable from each other by listeners, without having to listen to either amplifier.
The ears can be fooled. Scientists, composers, and musicians know this. That's why in a controlled scientific study, the interfering variables are either eliminated or controlled in a test. Sighted auditions of equipment without the proper controls are invalid to make scientific conclusions. Of course, one could make judgements and opinions of the sound - that's a starting point, not an end point.
Bob used his extensive knowledge and experience in amplifier design to duplicate the transfer function of the expensive amp in his amplifier, to a sufficiently high degree to win the challenge. The "transfer function" is well-known to scientists and engineers.
He also knew that if a difference between the two amplifiers is made sufficiently low to be inaudible by human ears, then the listeners could not identify any difference between the two amps. He used science and knowledge of human hearing, thresholds of hearing.
@Millercarbon said it first in this thread, that science is a method. Bob used the scientific method, and technology by measurements of the amplifier to make both amplifiers sound indistinguishable from each other by listeners, without having to listen to either amplifier.
The ears can be fooled. Scientists, composers, and musicians know this. That's why in a controlled scientific study, the interfering variables are either eliminated or controlled in a test. Sighted auditions of equipment without the proper controls are invalid to make scientific conclusions. Of course, one could make judgements and opinions of the sound - that's a starting point, not an end point.