Setup, Clip Limiter, HPF Hi-Pass Filter

SETUP

Clip Limiter

Clipping is the result of an amplifier running into a power supply limitation. The maximum output voltage that any amplifier can produce is limited by its power supply. Attempting to output a voltage (or current) level that exceeds the power supply results in a “flattenin” effect on the signal, making it’s waveform look cut off or “clipped”. A clipped waveform exhibits extreme harmonic distortion, dominated by large amplitude odd-ordered harmonics and making it sound harsh or dissonant.

The clip limiter detects this and reduces the gain to minimize the amount of overdrive. To preserve as much of the program dynamics as possible, limiting reduces the average program level until peaks barely clip. Each channel has its own clip limiter, and you can switch it on or off.

When driving full-range speakers, clip limiting reduces high frequency distortion caused by bass overload. It also protects higher frequency drivers from excess overdrive and harsh clipping harmonics.

HPF (Hi-Pass Filter)

A filter having a passband extending from some finite cutoff frequency (not zero) up to infinite frequency. Also known as a low-cut filter. HPF rolls off signals below 30Hz or 50Hz, removing the frequencies below the selected roll off. Reproduction of the signal’s bass portion is thus optimized, since ultra-low, distracting frequencies are eliminated, and more power is available for the reproduction of the wanted segment of the signal.

You should set up the filters so they best suit the frequency response of your speakers, since some speakers are particularly sensitive to over-excursion. The 50Hz filter works well with most compact full-range speakers.