ChaffVerb

An audio plugin utilizing pitch shifting, echo and reverb, ChaffVerb can create sounds that vary from shimmers to whale songs.

Plugins are provided in LV2, VST, VST3 and CLAP formats, compiled for Linux environments. With a working hvcc environment, the patch should compile for other systems.

Parameters

• A: LFO Section

  • LFO Period

    • The Low Freq Oscillator, time period

  • LFO Steps (Type2 LFO only)

    • The number of steps in the STEP LFO type. This is an integer value, but displayed as a float (limitation of hvcc).

  • LFO Steps Scale (Type 2)

    • A multiplier applied to the STEP LFO

  • LFO Switch

    • The Low Freq Oscillator, On/Off

  • LFO Type

    • The Low Freq Oscillator types:
      • RAMP (0)
      • SINE (1)
      • STEP (2)
    • hvcc doesn't do integer controls, so these are floats: (0.0-0.99, 1.0-1.99, 2.0-2.99)

• B: General Shifts Section

  • General Offset

    • A general offset added after the LFO

  • General Scale

    • A general multiplier after the LFO

• C: Random LFO Section

  • Random LFO Offset

    • A random offset added after the general offset & scale

  • Random LFO Period

    • The random LFO, time period

  • Random LFO Scale

    • A random multiplier, after the general offset & scale

  • Random LFO Switch

    • The random LFO, On/Off

• D: Shift Transpose Section

  • Shift Microtone

    • A float (+/-1.0)added to the transpose integer, for other intervals (although offsets and scalers do the same)

  • Shift Transpose

    • The base amount of pitch-shifting applied

• E: FX Level and Pitchshift Tuning Section

  • FX Level

    • Volume of effect

  • HiPass Freq

    • High Pass filter applied before the echo/delay

  • Shift Delay

    • The delay applied during the pitch shift

  • Shift Window

    • The pitch shift "window." The window effects the quality of the shift effect. The larger the window, the better the quality. However, this increases the audio latency. The audio quality does begin to noticably degrade below 100 ms (but may or may not be acceptable above OR below that mark, depending on the frequency, the shift amount, and other effects such as reverb).
    • Due to the increased aliasing, smaller windows can be used for complex 'bell' type sounds.

• F: FX Delay Section

  • FX Delay

    • Amt of echo/delay applied to the effect

  • FX Delay Feedback

    • Amt of echo/delay feedback

• Mix: Mixing Section

  • Dry Mix

    • Amt of Dry signal mixed in

  • Dry Vol

    • Volume of the Dry signal

  • Reverb Level

    • Level (strength) of the reverb effect

  • Reverb Vol

    • Volume of the reverb effect

When a parameter placement seems counter-intuitive (FX Level is NOT in the Mix section), it's because like sections, parameters are generally sequencial.

Example Patches

Patch Name	LFO Period	LFO Steps Scale (Type2)	LFO Steps (Type 2)	LFO Switch	LFO Type	General Offset	General Scale	Random LFO Offset	Random LFO Period	Random LFO Scale	Random LFO Switch	Shift Microtone	Shift Transpose	FX Level	HiPass Freq	Shift Delay	Shift Window	FX Delay	FX Delay Feedback	Dry Mix	Dry Vol	Reverb Level	Reverb Vol
	A:	A:	A:	A:	A:	B:	B:	C:	C:	C:	C:	D:	D	E:	E:	E:	E:	F:	F:	Mix:	Mix:	Mix:	Mix:
Default	1500	1	4	0	1	0	1	NA	NA	NA	0	0	16	0.7	2200	0	1000	500	0.65	0.45	0.1	0.75	0.55
2 Octave	NA	1	4	0	0	0	1	NA	NA	NA	0	0	24	0.7	2200	0	1400	500	0.3	0.45	0.1	0.75	0.55
Submare	1500	1	4	1	0	0	-2	NA	NA	NA	0	0	-5	0.7	100	0	1400	500	0.9	0.45	0.1	0.5	0.3
Shimmer	1500	1	4	1	1	0.7	0.25	NA	NA	NA	0	0	36	0.7	1500	0	3100	500	0.65	0.45	0.1	0.92	0.25
DeezBells	2040	0.6	6	1	2	0.05	-2	NA	NA	NA	0	0	36	0.6	900	0	330	675	0.75	0.45	0.1	0.85	0.3
DeezRize	2040	1	5	1	2	1	1.2	NA	NA	NA	0	0	12	0.7	500	0	3100	500	0.75	0.45	0.1	0.8	0.25
subterr	1250	-0.9	5	1	2	0.89	0.4	1.4	495	-1.9	1	0	5	0.7	600	90	2000	500	0.85	0.45	0.1	0.85	0.35
upterr	1250	-0.7	5	1	2	0.08	-1.96	-0.88	365	-1.2	1	0	5	0.6	800	130	475	670	0.75	0.45	0.1	0.85	0.27
goldkaos	1250	-0.7	4	1	2	-0.24	5.9	1.7	240	-1.6	1	0	24	0.6	700	400	2200	700	0.87	0.33	0.05	0.58	0.45
crickets	1250	5	4	1	2	-0.24	5.95	1.7	240	2.8	1	0	-36	0.6	1600	270	2200	900	0.88	0.33	0.06	0.58	0.44

Tips

• Offsets, scalers and LFOs can interact in interesting ways. Pitch can ramp up or down in a direction that's contrary to expectations. Experimentation is good...
• NA (Not Applicable) entries still display values. In it's current form, hvcc can't 'ghost out' unused controls. The 'NA' refers to an associated 'switch' parameter.
• Shift Transpose and Shift Microtone (Section D) are really just another pair of offsets, and like earlier offsets (and scaling), similarly effect the pitch shift.

About ChaffVerb

ChaffVerb is based on a Pure Data patch, and built with the Heavy (hvcc) Pd compiler and the DISTRHO Plugin Framework. It also leans heavily on Miller Puckette's G09.pitchshift.pd patch (converted to abstraction) and the std Rev2~.pd reverb patch, with a few modifications.

The Pd source patch is also included, and the plugin should build for any other OS that supports the "modern" version of hvcc (modern being support for python3).

• Miller Puckette and Pure Data
• hvcc, the 'Heavy' Pd compiler
  • Qudos to dromer for updating the original EnzienAudio code to python3
• DPF - DISTRHO Plugin Framework

No effort has been made to integrate a fancy GUI for the plugin.

ChaffVerb was written by Doug Garmon, and released under the MIT licence.

Installing the prebuilds

The Releases section has a zip file with pre-built Linux plugin binaries. There's currently no installer, so just move the associated plugins to your home .lv2, .vst, and .clap directories. And the .vst3 directory as well, although I've not tested the VST3 version.

The build version (Makefile) includes a simple installation script, for local (user home) use.

Building ChaffVerb

Install the heavy compiler: (See the section on the 'namefix' version below FIRST, if that's desired.)

$ pip3 install hvcc

Clone the ChaffVerb source (and the DISTHRO Plugin Framework):

git clone --recursive https://github.com/GModal/ChaffVerb

Open a terminal (or cd) to the ChaffVerb directory, then enter:

make

There's a simple install option for local (single user) install:

make install

The plugin folders for each type must be present for install to work. These are named .lv2, .vst, and .clap, in your home directory. Each plugin can be manually copied to the local directories as well.

The hvcc 'namefix' version (the release builds)

The release versions of ChaffVerb were built with a somewhat 'hacked' version of hvcc that allows inserting non-alphanumberic characters via codes in the Pd patch, and converts them for use in the hvcc-generated plugin interfaces.

The source does NOT default to the 'namefix' version, however. Patching hvcc leads to a more complicated build process.

Read the 'namefix' build instructions