Short: OctaMED nsm plugin - better echo effect Author: claude.heiland-allen@lincoln.oxford.ac.uk (Claude Heiland-Allen) Uploader: claude heiland-allen lincoln oxford ac uk (Claude Heiland-Allen) Type: mus/edit Version: 1.4 Requires: nsm patched OctaMED SoundStudio Architecture: m68k-amigaos $VER: cha_echo.readme 1.4 (2000.02.26) © Claude Heiland-Allen BUGFIX: could divide by 0 if instrument default pitch >= C-4 A better echo effect for processing samples using OctaMED SoundStudio with the nsm patch system. Features: - reasonably fast - sounds good (much better than OSS) - easy to use command line interface - parameters use standard units (eg. seconds instead of a number of samples) - feedback means echoes die away naturally (not just a fixed number of repeats) - highly modular object oriented design allows code to be shared between plugins (see mus/edit/cha_source.lha) Usage: cha_echo FROM/A,TO/A,DELAY/K,DECAY/K,REVERB/K, FREQ=FREQUENCY,RATE/K,VOLUME/K - FROM source sample number (OSS style, 1 .. 1V) - TO destination sample number (can be same as FROM) (if the output space is too short then the size of the sample is increased automatically) - DELAY the delay time between echoes in seconds - DECAY the decay factor between echoes (-1 .. 1) - REVERB the reverberation time in seconds (time until the sound has decayed by -60 dB) - FREQUENCY instead of delay, a frequency can be used (one less calculation for you to do yourself) - RATE the sampling rate (default to the default pitch of the source sample, or C-3 (16574 Hz) if that instrument has no default pitch) - VOLUME the volume factor for the output (default 1), use values < 1 if you get distortion (usually with high decay / reverb values) - exactly two of DELAY, DECAY, REVERB, and FREQUENCY must be specified, but it is useless to specify DELAY and FREQUENCY together as these control the same aspect of the echo Examples: - cha_echo 1 2 delay 0.2 decay 0.333 fairly average echo, enough to be noticeable - cha_echo 1 2 freq 200 reverb 0.25 rate 22050 very short echoes sound strange :) Bugs: - due to the 32 bit floats used internally, accuracy may waver when using extreme values of REVERB - the routine to add space to the destination tends to add too much space - the error messages aren't very informative Tips: - control-C interrupts processing, for emergencies - centralize the sample before echoing, otherwise the offset error increases Future: - cha_autoecho: using the current tempo, echo with delay set in terms of a number of lines (that will probably be a separate program that controls this one) Claude