we are discussing this in another forum. Due to the restricted model that LTSPICE must use only rise/fall time can be simulated correctly where operation is in the linear region, no saturation effects. A simple test however is sim of a transistor as a switch where the spec has t on toff , t off includes storage time. I found the sims are too good.
should be fast enough to permit use of feedback, but not so fast as to amplify Mhz signals.
could be 0.5v/us and sound perfect.
You need to see how the amplifier drives capacitive loads in // with the resistance, there you will see why some amplifiers sound good!
You don't need a bandwidth over 20khz for audio, only for feedback purposes.
I choose my amp to do 0mph, stationary in my living room for music.
could be 0.5v/us and sound perfect.
You need to see how the amplifier drives capacitive loads in // with the resistance, there you will see why some amplifiers sound good!
You don't need a bandwidth over 20khz for audio, only for feedback purposes.
I choose my amp to do 0mph, stationary in my living room for music.
I consider the case settled. In terms of sonic quality full power bandwidth 22-30 kHz is close to over-engineering except for reproduction of machine gun shooting. The rise time of semiconductor amps is another story much different from tube amps. Rules of thumb open loop GBW such as to permit two pole lead lag compensation and keep every stage always out of saturation. That may justify rise time of 50µsec
I agree with you. Also, the blinkered pursuit of high slew rate can lead to very bad sonic side-effects.
Audio is full of these red herrings. It is because of ignorance. When people are groping in the dark they will latch on to a conjecture, even a flimsy one, and pursue it out of desperation. Then they will promote it heavily because it gives them a competitive differentiator to market with. Amateurs have the advantage of not having to suffer this.
Audio is full of these red herrings. It is because of ignorance. When people are groping in the dark they will latch on to a conjecture, even a flimsy one, and pursue it out of desperation. Then they will promote it heavily because it gives them a competitive differentiator to market with. Amateurs have the advantage of not having to suffer this.
Just looked at my notes. I think the 19uV/S is with no compensation in the feedback loop.
(Nat Semi also had a better pulse generator -- I just used a PG501 -- stated rise time 3.5nS 2 to 5V, mine is about 5nS).
PS -- you'll find that a square wave is extremely taxing for a chipamp -- the SPIKE protection will kick in and affect the results when the duty cycle is this high.
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