There are two reasons why this is not the correct story. Transient distortion occurs with or without NFB. NFB can suppress TIM just as it suppresses THD and AIM. Read Cordell.
The notion that feedback comes 'too late' is nonsense, transit times are many orders of magnitude faster than the fastest audio signal. Transients in audio are just as band-limited and rise-time limited by the audio bandwidth as any other signal.
Read Putzeys.
Jan
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But that’s the trick of AB, no? No crossover distortion for the first few watts.
But it runs at the very "low" end at the transistor curve where linearity is not as good as a "real" class A amp running at much higher bias?
long time ago I was into technics gear, and off course had many amplifiers
do not remember exact model, 70 watts, super low distortion, nice polish silver front with beautiful fluorescence meter (that's why I bought it), it had clever circuitry to recognize speaker resistance, adopted to power supply voltage accordingly, and so on...
distortion 0.007%
yet it sounded like crap
crap at low level, crap at full power, just plain boring
my rebuilt 2 watts 5% distortion SE EL84 magnavox was clearly superior, pleasure to listen to
I measured technics, nothing wrong with it, just horrible sound
sold it, years later I have seen it again, could not resist, bought it
same story! again the same crapy dry sterile boring sound
I still have magnavox
do not remember exact model, 70 watts, super low distortion, nice polish silver front with beautiful fluorescence meter (that's why I bought it), it had clever circuitry to recognize speaker resistance, adopted to power supply voltage accordingly, and so on...
distortion 0.007%
yet it sounded like crap
crap at low level, crap at full power, just plain boring
my rebuilt 2 watts 5% distortion SE EL84 magnavox was clearly superior, pleasure to listen to
I measured technics, nothing wrong with it, just horrible sound
sold it, years later I have seen it again, could not resist, bought it
same story! again the same crapy dry sterile boring sound
I still have magnavox
Most fears in life are based on limited understanding. We fear what we don't understand. Even vaccinations ;-)
(Sorry for the off-topic, but it is such a nice example).
Jan
Distortion 0.007% at 1kHz can sound crap. At full power sound more crap usually because slew rate too low.
You should make slew rate is not the limiting factor so it can cause TIM. You should make IM distortion low or distortion is low for all audio frequency. If you can not reduce distortion low enough (below 0.001%) than you should make harmonic profile of the distortion is monotonic or H2 dominant. To achieve it the easy way is using class A. Class AB also can, but more difficult. If you like using amplifier as effect you can make distortion more than 0.1% with H2 dominant.
300kHz full power bandwidth is very easy to design so slew limiting never happen. Jan Didden built amplifier with 10Mhz full power bandwidth. And Edmond Stuart with Sync08 built amplifier with 0.0001% at all audio frequency.
Much the same myself with Crown gear in the 70's. Bought DC300A and IC150 because specs lower then any test equipment available at the time. The DC300A was a dependable long lasting monster but never could sound as good as a decent tube amplifier. The IC-150 is now considered as never sounding very good. Great distortion numbers though. Just shows ears should be the final judge and not numbers.
Yes, because you do not understand the relationship of amplifier measurement and the sound perception. Amplifiers measurement are not only distortion at 1kHz.