A collection of Csound reverb algorithms implemented as a single #include file.

There are basically two kind of reverb macros : preset reverbs (you only have to select the reverb name, index, sound source, sound output and preset number if necessary) and user definable reverbs, which may require lots of extra arguments specific to each reverb algorithm.

The reverbs are named as follows:

rvb1m , rvb2m	preset mono reverbs
rvb1s , rvb2s	preset noto to stereo or stereo to stereo reverbs
xrvb1m, xrvb2m	user configurable mono reverbs
xrvb1s, xrvb2s	user configurable mono to stereo or stereo to stereo reverbs

For simplicity all the reverbs are static (ie. you cannot change the reverberation time dinamically), but I´ll probably add some dynamic reverbs soon.

Only monophonic or stereophonic reverbs are included by now.

Josep M Comajuncosas, August 2000

User-configurable (w. presets) mono to stereo reverb

Convolve-based reverb (from Varga István EffectProc. file)

Not usable for MIDI events. The output is delayed according to the convolve docs.

Author : Josep M Comajuncosas

in: input

outL,outR : output

IR : impulse response number for a file named "convolve.IR"

dry :dry/wet mode. If dry !=0 output the default (suggested) wet/dry mix

Preset mono reverb

MN3011 BBD Reverb

Multitap delay line with feedback.

Author : Cook

in: input

out : output

User configurable stereo reverb

8 delay line FDN reverb, with feedback matrix based upon physical modeling scattering junction of 8 lossless waveguides of equal characteristic impedance. Based on Julius O. Smith III, "A New Approach to Digital Reverberation using Closed Waveguide Networks," Proceedings of the International Computer Music Conference 1985, p. 47-53 (also available as a seperate publication from CCRMA), as well as some more recent papers by Smith and others.

Coded by Sean Costello, October 1999

inL,inR : left and right inputs

outL,outR : left and right outputs

gain : gain of reverb. Adjust empirically for desired reverb time. .6 gives a good small "live" room sound, .8 a small hall, .9 a large hall, .99 an enormous stone cavern.

pitchmod : amount of random pitch modulation for the delay lines. 1 is the "normal" amount, but this may be too high for held pitches such as piano tones.

fco : Cutoff frequency of lowpass filters in feedback loops of delay lines, in Hz. Lower cutoff frequencies results in a sound with more high-frequency damping.

reverb settings for Costello´s phased string ensemble.

Simple implementation of Feedback Delay Network (FDN) reverb, as described by John Stautner and Miller Puckette, "Designing Multi-Channel Reverberators," Computer Music Journal, Vol. 6, No. 1, Spring 1982, p.52-65. This version sticks to implementing the basic FDN structure, and leaves out most of the FIR multitap delay lines and filtering used for the early reflections. For sounds with non-percussive attacks, this simple implementation works great.

by Sean Costello, August 23-26, 1999

inL,inR : left and right inputs

outL,outR : left and right outputs

User configurable stereo reverb

Simple implementation of Feedback Delay Network (FDN) reverb, as described by John Stautner and Miller Puckette, "Designing Multi-Channel Reverberators," Computer Music Journal, Vol. 6, No. 1, Spring 1982, p.52-65. This version sticks to implementing the basic FDN structure, and leaves out most of the FIR multitap delay lines and filtering used for the early reflections. For sounds with non-percussive attacks, this simple implementation works great.

by Sean Costello, August 23-26, 1999

gain : gain of reverb

pitchmod : amount of random pitch mod, between 0 and 1

delaytime : controls overall length of delay lines

filt : controls cutoff of lowpass filters at outputs of delay lines

freq : controls frequency of random noise

Preset stereo reverb

4 delay multiple feedback reverb by Hans Mikelson

Appartently some presets are unstable. Be careful!

preset : preset number

User configurable stereo reverb

4 delay multiple feedback reverb by Hans Mikelson

inL,inR : left and right inputs

outL,outR : left and right outputs

fdbk : feedback amount

fco : frequency cutoff of the lowpass filters in the feedback loop

dlt1L,dlt2L,dlt3L,dlt4L,dlt1R,dlt2R,dlt3R,dlt4R: delay time, in milliseconds, of the 4 left

and the 4 right delay lines

fchp : frequency cutoff of the highpass filter at the reverb output

Preset stereo reverb

3 delay multiple feedback reverb by Hans Mikelson

inL,inR : left and right inputs

outL,outR : left and right outputs

preset : preset number

User configurable mono reverb

3 delay multiple feedback reverb by Hans Mikelson

in : input

out : output

fdbk : feedback amount

fco : frequency cutoff of the lowpass filters in the feedback loop

dlt1,dlt2,dlt3 : delay time, in milliseconds, of the 3 delay lines

BaBo model (a Ball within a Box) by David Rochesso (20-11-96) used as a reverberation device.

Note that the original BaBo code allows dynamic modification of the room size as well as the placement of the sound source and the pickups.

I have no useful presets by now, any contribution would be greatly welcome!

inL,inR : left and right inputs

outL,outR : left and right outputs

lx,ly,lz : room dimensions

sx,sy,sz : source coordinates

Rx,Ry,Rz : right pickup position

Lx,Ly,Lz : left pickup position

alfa : attn. coeff. for the delay lines

eps : (?)

early1,early2 : early/difusse controls for the 2 stereo channels

ref : weighting parameter for the early reflections

dir : weighting parameter for the direct signal

Lyon´s echo1 reverb;includes d/w mix!!

gain,echotime (as the name implies)

Lyon´s echo2 reverb

Lyon´s gator2 reverb mono input

Lyon´s gator2 reverb stereo input

E. Lyon´s Lmultitap reverb

E. Lyon´s Lmultitap2 reverb

Lyon´s Rev1 reverb (dry/wet mix of .65/.35 in the orgininal file)

Lyon´s Rev2 reverb

Panning tap based stereo reverb : mono input only

outputs only the wet signal, dry/wet mix suggested in the original score : .5/.5

E.Lyon´s Rev3 instrument,

a tighter reverb (Lyon uses a d/w mix of .5/.5)

Lyon´s Rev4 reverb (Lyon suggests a d/w mix of .1/.9)

Lyon´s Rev5 reverb

Lyon´s Rev6 reverb

Lyon´s Rev7 reverb

Mono -> mono reverb, Industrial sound

Lyon´s Rev8 reverb

Mono -> mono reverb with resonance moving

Lyon´s Rev8 reverb stereo->stereo version

Lyon´s Rev9 reverb

Lyon´s Rev10 reverb

2in 2out wet reverb

Lyon´s Rev11 reverb

Lyon´s Rev12 reverb

Chorus, comb based reverb - stereo in stereo out,

Lyon´s Reverb2 reverb

Panning tap based stereo reverb : mono input only

Brandt´s Moorer´s reverb implementation

Moorer's circulating-delay reverb, w/ lowpasses and fine-tuned early echoes.

fancy Moorer-17

rvbt : reverb time. Used to set up a sort of virtual room model with the requested reverberation time.