I believe in an additional objection to the Richard Clark test method.
The Speaker.
All speakers certainly do not react the same to all loads. I'm not even talking the difference between speakers which have a preference to current or voltage source amps.
Many speakers have wacky characteristics and huge phase swings, even if impedance would appear to be within reason. Worst case? Combine a phase shift of 50 or 60 degrees with an impedance dip to say.....3 ohms. Low power amps or amps which don't like this kind of behavior need not apply. Even if a tube amp would meet Clark's criteria, I'm sure if you compared a heavily capacitive speaker, you'd notice a difference.
Perhaps, when running within limits amps do sound alike, but for some amps and speaker combinations, those limits are either at low levels or maybe even frequency limited. I'd love to hear my panels with 6 or 8 SET watts.
And finally, while I hate to drag Bob Carver into this, I think he demonstrated differences between amps based on Transfer Function. He would somehow connect 2 amps to the same speaker. Any sound the speaker made was the DIFFERENCE between the amplifiers transfer function. After adjustment, the speaker would 'null' and at least for THAT speaker, the amps could be considered identical.
And Xti, the difference between 5k and 7k is negligible. Any manufacturer should be pretty much able to do their best work for that kind of money. Toss something like 700$s worth of Onkyo A-9555 into the mix and see what'cha get. You can probably get the Onkyo for what would amount to a TRUE nutty hi-end guy's pocket change.
The Speaker.
All speakers certainly do not react the same to all loads. I'm not even talking the difference between speakers which have a preference to current or voltage source amps.
Many speakers have wacky characteristics and huge phase swings, even if impedance would appear to be within reason. Worst case? Combine a phase shift of 50 or 60 degrees with an impedance dip to say.....3 ohms. Low power amps or amps which don't like this kind of behavior need not apply. Even if a tube amp would meet Clark's criteria, I'm sure if you compared a heavily capacitive speaker, you'd notice a difference.
Perhaps, when running within limits amps do sound alike, but for some amps and speaker combinations, those limits are either at low levels or maybe even frequency limited. I'd love to hear my panels with 6 or 8 SET watts.
And finally, while I hate to drag Bob Carver into this, I think he demonstrated differences between amps based on Transfer Function. He would somehow connect 2 amps to the same speaker. Any sound the speaker made was the DIFFERENCE between the amplifiers transfer function. After adjustment, the speaker would 'null' and at least for THAT speaker, the amps could be considered identical.
And Xti, the difference between 5k and 7k is negligible. Any manufacturer should be pretty much able to do their best work for that kind of money. Toss something like 700$s worth of Onkyo A-9555 into the mix and see what'cha get. You can probably get the Onkyo for what would amount to a TRUE nutty hi-end guy's pocket change.