Yes, I have read this thread in its entirety. You could not have made it anymore clear. Go back to the beginning of this thread and read your own post. Not a false statement.
Obviously I could have been more clear or this conversation would not be happening!
Al’s got it right. Note where I say ’good’ twice in the statement Al is quoting.
As I have mentioned before, we’ve been playing with Class D for about the last 15 years. While I think they have gotten much better (15 years ago they were a joke) I’ve yet to hear one that keeps up with a ***good*** amplifier of conventional design (note emphasis; FWIW I’m used to listening to some pretty ’good’ amplifiers...). High end audio is pretty variable and I know of amps that are considered high end that I personally don’t think are all that good. I know of one such amp that has balanced inputs yet its CMRR (Common Mode Rejection Ratio) is about 18 which is pretty terrible if not outright criminal.
So I can see the interpretation issue. Most class D amps have specs and sound that are similar to many midfi amps (take a look at a Kenwood car stereo’s specs and compare to many ’high end’ amps and you will see that there’s not a lot of difference). Some don’t; they’re better. And they will continue to improve.
For example the scan frequency is continuing to rise. George makes a pretty big point about this. You can’t scan at 100KHz and get good high end resolution. 250KHz is in fact marginal if you really want to do it right.
As I mentioned before, you can get high power high speed output devices that switch at the speeds needed, but they cost so much right now that the resulting amplifier would be a lot more expensive than a tube amp of the same power would be (tubes are usually the most expensive form of power). So as a result no-one uses devices like that. In fact many designers simply use chip sets so they’re locked into the performance of whatever the semiconductor house provides (who rarely have audiophile interest at heart).
