Fundamentals of Audio Processors: Digital Processor Output Functions
There are many audio processors in life. What are the basic aspects of an audio processor? Do you understand the digital processor's output functions?
Signal Input Routing (ROUTE): Selects input source for this output channel (e.g., Input A, Input B, Mix A+B, Mono Mix).
High-Pass Filter (HPF): Sets lower frequency limit. Used for speaker high-pass (e.g., crossover point). Parameters: Frequency, Filter Type (commonly Linkwitz-Riley, Bessel, Butterworth—choose L-R if unsure), Filter Slope (6, 12, 18, 24, 48 dB/oct—steeper slope = sharper cutoff).
Low-Pass Filter (LPF): Sets upper frequency limit. Used for speaker low-pass (e.g., subwoofer crossover). Parameters same as HPF.
HPF + LPF = Bandpass Filter. E.g., for a 3-way speaker crossed at 500Hz/3000Hz: LF LPF=500Hz, MF HPF=500Hz & LPF=3000Hz, HF HPF=3000Hz. Type: L-R, Slope: 24dB/oct—usually correct. Some processors combine filter type and slope.
Output EQ: Similar to input EQ, usually parametric only (no graphic).
Output Polarity: Reverses output signal polarity. Some processors have Phase angle adjustment (advanced).
Output Limiter: Key parameters: Threshold (Start Level), Attack Time, Release Time. Set threshold based on amp/speaker specs—prevent clipping (amp red light). Attack/Release: Slow attack/fast release for bass; Fast attack/slow release for highs; Medium for mids.
Signal Input Routing (ROUTE): Selects input source for this output channel (e.g., Input A, Input B, Mix A+B, Mono Mix).
High-Pass Filter (HPF): Sets lower frequency limit. Used for speaker high-pass (e.g., crossover point). Parameters: Frequency, Filter Type (commonly Linkwitz-Riley, Bessel, Butterworth—choose L-R if unsure), Filter Slope (6, 12, 18, 24, 48 dB/oct—steeper slope = sharper cutoff).
Low-Pass Filter (LPF): Sets upper frequency limit. Used for speaker low-pass (e.g., subwoofer crossover). Parameters same as HPF.
HPF + LPF = Bandpass Filter. E.g., for a 3-way speaker crossed at 500Hz/3000Hz: LF LPF=500Hz, MF HPF=500Hz & LPF=3000Hz, HF HPF=3000Hz. Type: L-R, Slope: 24dB/oct—usually correct. Some processors combine filter type and slope.
Output EQ: Similar to input EQ, usually parametric only (no graphic).
Output Polarity: Reverses output signal polarity. Some processors have Phase angle adjustment (advanced).
Output Limiter: Key parameters: Threshold (Start Level), Attack Time, Release Time. Set threshold based on amp/speaker specs—prevent clipping (amp red light). Attack/Release: Slow attack/fast release for bass; Fast attack/slow release for highs; Medium for mids.