Most Class D amplifier designs require a filter at the output to remove the high frequency switching noise that is present in the signal. Various designs use different types of filters with varying cutoff frequencies. I doubt that any are designed to remove frequencies under 20KHz, but Class D amps are generally more frequency limited at the high end than conventional output stages can be. Whether this is audible can be a subjective question. Some engineers feel that in order to avoid introducing any phase shift to the audible high frequencies requires an amp to have a flat bandwidth response extending to many multiples beyond the audible frequency limit.
Bandwidth Limitations Of Class D Amps??
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Audiogon member Kijanki said :
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Audiogon member Kijanki said :
Some people argue that class D, as good as it is for the money, cannot really compete with best traditional SS amp. I can see that, especially with still limited bandwidth...What are the bandwidth limitations of class D amps, and is it audible?
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