Does this help? Slew rate: The term used to define the maximum rate of change of an amplifier's output voltage with respect to its input voltage. In essence, slew rate is a measure of an amplifier's ability to follow its input signal. It is measured by applying a large amplitude step function (a signal starting at 0 volts and "instantaneously" jumping to some large level [without overshoot or ringing], creating a step-like look on an oscilloscope) to the amplifier under test and measuring the slope of the output waveform. For a "perfect" step input (i.e., one with a rise time at least 100 times faster than the amplifier under test), the output will not be vertical; it will exhibit a pronounced slope. The slope is caused by the amplifier having a finite amount of current available to charge and discharge its internal compensation capacitor. 2. Mathematics. Slew rate is defined to be the maximum derivative of the output voltage with respect to time. That is, it is a measure of the worst case delta change of voltage over a delta change in time, or the rate-of-change of the voltage vs. time. For sinusoidal signals (audio), this equals 2 pi times the maximum frequency, times the maximum peak output voltage. You must also consider the Damping Factor of the amp, which deals with how well it handles back emf from the speakers.
what is Slew Rate ?
I am not a audio specialist so I would like your suport: I have a Jeff rowland model 1 amplifier and i'd like to know what it's specifications mean: most things I understand, but what is the "slew rate"? It's specified in the manual: 70 volts per microsecond. is this what technically determines how quickly the amplifier amplifies a siganl from the pre-amp? In that case, is a smaller value better? How can this be described from an empirical viewpoint? Is this what audiophiles describe by "speed", as in a "fast" amplifier; my stereo sounds good to me, but in real life music sounds better. ...Of course it does! Actually, vinil sounds much more realistic than CD's, but still I notice a lack fullness and "fastness" of music coming out of my speakers. I would like to somehow improve this sound area of my stereo. Does the slew rate relate to these sound qualities or do I need to look elsewhere? I wish I could just audition different equipment and choose the one I like best, but living in Chicago, I have access to only those brands that my local shop provides. I need some criteria to narrow down my search. Great site! yours, Herman