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Update: 2023-12-02

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MembraneSynth is a synthesizer that resembles sound of percussions with membrane, like bass drum or tom tom. Some strange noise can also be made by utilizing oscillation caused by self-modulation.

full package contains following builds.

Linux build is built on Ubuntu 22.04. If you are using distribution other than Ubuntu 22.04, plugin will not likely to run. In this case, please take a look at build instruction.

macOS package is recommended for macOS user. I can’t purchase Apple Developer Program, therefore installation requires a workaround to bypass Gatekeeper. Details of workaround are written in Installation -> macOS Specific section.


Feel free to contact me on GitHub repository or

You can fund the development through Current goal is to purchase M1 mac for better macOS support. 💸💻



Move *.vst3 directory to:

DAW may provides additional VST3 directory. For more information, please refer to the manual of the DAW.


Notice: Some plugins don’t have presets provided by Uhhyou Plugins.

Presets are included in the plugin package linked at the top of this page. To install presets, follow the steps below.

  1. Download plugin from a link at the top of this page.
  2. Extract downloaded zip file.
  3. Open presets directory placed in extracted package.
  4. Move Uhhyou directory into an OS specific preset directory (see below).

Below is a list of preset directories for each OS.

Preset directory name must be the same as the plugin. If preset directory does not exist, create it.

Windows Specific

If DAW doesn’t recognize the plugin, try installing C++ redistributable (vc_redist.x64.exe). Installer can be found in the link below.

Linux Specific

On Ubuntu 22.04, those packages are required.

sudo apt install libxcb-cursor0  libxkbcommon-x11-0

If DAW doesn’t recognize the plugin, take a look at Package Requirements section of the link below and make sure all the VST3 related package is installed.

REAPER on Linux may not recognize the plugin. A workaround is to delete a file ~/.config/REAPER/reaper-vstplugins64.ini and restart REAPER.

macOS Specific

Important: full package is not confirmed working. When using full, try removing following files.

macOS package doesn’t contain above files. Also, all packages are in “ad-hoc signing” state set by codesign command.

Remove Quarantine

When trying to run plugin first time, following message may appear on macOS.

<PluginName>.vst3 is damaged and can't be opened. You should move it to the Trash.

In this case, open terminal and try running one or both of following command to unzipped .vst3 directory. Replace /path/to/PluginName.vst3 according to your install location.

xattr -rd /path/to/PluginName.vst3
xattr -rc /path/to/PluginName.vst3

Bypass Gatekeeper

Plugin may be considered as unsigned/un-notarized application. In this case, open System Preferences, go to Security & Privacy → General, then click the Open Anyway button. The offcial Apple help page linked below has screenshots for the procedure. See “If you want to open an app that hasn’t been notarized or is from an unidentified developer” section.

If the plugin is still not working, try changing install location to /Library/Audio/Plug-ins/VST3/ or /Users/$USERNAME/Library/Audio/Plug-ins/VST3/ whichever still haven’t tried.

If all the above methods do not work, try following the steps below.

  1. Open terminal and run sudo spctl --master-disable.
  2. Go to System Preferences → Security and Privacy → General → Allow apps downloaded from, then select “Anywhere”.

Beware that steps above degrades security of your system. To revert the settings, follow the steps below.

  1. Go to System Preferences → Security and Privacy → General → Allow apps downloaded from, then select option to “App Store and identified developers”.
  2. Open terminal and run sudo spctl --master-enable.

Applying codesign

Note This section may not relevant to macOS packages. However it’s not verified. (GitHub issue)

To use full package, following command might be used.

sudo codesign --force --deep -s - /path/to/PluginName.vst3

codesign might not be available without installing Xcode.


GUI Style Configuration

At first time, create color config file to:

style.json will be loaded for each time a plugin window opens.

Several color themes are available on the link below.

Below is a example of style.json.

  "fontFamily": "Tinos",
  "fontBold": true,
  "fontItalic": true,
  "foreground": "#000000",
  "foregroundButtonOn": "#000000",
  "foregroundInactive": "#8a8a8a",
  "background": "#ffffff",
  "boxBackground": "#ffffff",
  "border": "#000000",
  "borderCheckbox": "#000000",
  "borderLabel": "#000000",
  "unfocused": "#dddddd",
  "highlightMain": "#0ba4f1",
  "highlightAccent": "#13c136",
  "highlightButton": "#fcc04f",
  "highlightWarning": "#fc8080",
  "overlay": "#00000088",
  "overlayHighlight": "#00ff0033"

Font Options

Following is a list of font options.

To use custom font, place *.ttf file into custom font path: *.vst3/Contents/Resources/Fonts.

Notice: If the combination of fontFamily, fontBold, fontItalic is not exists in custom font path, default font of VSTGUI is used.

If fontFamily is set to empty string "", then "Tinos" is used as fallback. If the length is greater than 1 and the font family name doesn’t exists, default font of VSTGUI is used.

Styles other than bold, italic or bold-italic are not supported by VSTGUI. For example, “Thin”, “Light”, “Medium”, and “Black” weights cannot be used.

Color Options

Hex color codes are used.

First letter # is conventional. Plugins ignore the first letter of color code, thus ?102938, \n11335577 are valid.

Do not use characters outside of 0-9a-f for color value.

Following is a list of color options. If an option is missing, default color will be used.


Right Click on the controls pops up a context menu provided by DAW.

Knob and slider provides following controls:

Control with many blue vertical bars (BarBox) have some keyboard shortcuts. LFO Wave on Main tab and Gain, Width, Pitch, Phase on Wavetable tab are using BarBox. Shortcuts are enabled after left clicking BarBox and mouse cursor is on the inside of BarBox. Cheat sheet is available on Infomation tab.

Input Control
Left Drag Change Value
Shift + Left Drag Change Value (Snapped)
Ctrl + Left Drag Reset to Default
Ctrl + Shift + Left Drag Change Value (Skip Between Frames)
Middle Drag Draw Line
Shift + Middle Drag Edit One Bar
Ctrl + Middle Drag Reset to Default
Ctrl + Shift + Middle Drag Toggle Lock
a Alternate Sign
d Reset Everything to Default
D Toggle Min/Mid/Max
e Emphasize Low
E Emphasize High
f Low-pass Filter
F High-pass Filter
i Invert Value (Preserve minimum)
I Invert Value (Minimum to 0)
l Toggle Lock under Mouse Cursor
L Toggle Lock for All
n Normalize (Preserve minimum)
N Normalize (Minimum to 0)
p Permute
r Randomize
R Sparse Randomize
s Sort Descending Order
S Sort Ascending Order
t Subtle Randomize (Random walk)
T Subtle Randomize (Converge to 0)
z Undo
Z Redo
, (Comma) Rotate Back
. (Period) Rotate Forward
1 Decrease
2-4 Decrease 2n-4n
5-9 Decimate by holding 2n-5n

Snapping is not available for all BarBox. If you’d like to have snapping for certain BarBox, feel free to open issue to GitHub repository.

Edit One Bar with Shift + Right Drag holds a bar under the cursor when mouse right button is pressed. Then only changes that one bar while holding down mouse right button.

Toggle Lock with Ctrl + Shift + Right Drag behaves as line edit. When right mouse button (RMB) is pressed, it holds the opposite state of the bar below mouse cursor, then use the state for the rest of bars. For example, if RMB is pressed on a locked bar, dragging unlocks bars while holding down RMB.

Some BarBox has scroll bar to zoom in. Scroll bar has handles on left end and right end. To control zoom, use Left Drag on one of the handle. Scroll bar also has following controls:


Recommend to insert limiter after MembraneSynth because output amplitude varies greatly.

It may oscillates when following conditions are met:

Oscillation can be utilized for some noisy drone or sound effects, however it can be a problem when making percussion sounds. Recommend to always enable Envelope for percussion sounds.

Block Diagram

If the image is small, use Ctrl + Mouse Wheel or “View Image” on right click menu to scale.

Diagram only shows overview. It’s not exact implementation.


Characters inside of square brackets [] represents unit. Following is a list of units used in MembraneSynth.

FDN is short for feedback delay network. See block diagram for details about FDN.


Output [dB]

Output gain.


When checked, output gain is normalized to keep almost same gain regardless of Impact -> Amplitude.

2x Sampling

When checked, it enables 2-fold oversampling.


Impact section provides parameters for excitation. Excitation here means the signal that imitates the impact of stick and membrane.

Amplitude [dB]

Maximum amplitude of excitation. Roughly represents the intensity of impact.

Decay [s]

Decay time of excitation. Roughly represents the time that the membrane returns to resting position after impact.

Increasing the value of Decay adds more low frequency. Depending on other parameter settings, rattling may vanish when Decay is greater than some certain value.


Position introduces bias the FDN input gain to resemble the position of impact.

Intention was to represent the center of membrane for Position = 0, and the rim of membrane for Position = 1. However, it doesn’t make much difference to the output sound.


Tuning section provides pitch related parameters.

Note that most of the time, the output of MembraneSynth might be out of tuning. If it is required to tune the pitch exactly to provided note, recommend to render the output sound, and use external sampler.

Semitone, Cent

Pitch in semitone or cent. 1 semitone equals to 100 cents.

Equal Temp., A4 [Hz]

Equal Temp. is abbreviation of equal temperament (ET). When Equal Temp. is 12, then the tuning becomes standard 12 ET. Setting Equal Temp. to less than 12 might increase the range of note that doesn’t change output sound, due to the internal pitch becomes too high or too low.

A4 [Hz] is freqeuncy of note A4.

P.Bend Range [st.]

Range of pitch bend in semitone.

Slide Time [s]

Time to slide the pitch of latest note.

Note that the time indicated in user interface is not exact. Internally, the value is converted to cutoff frequency of smoothing filter.

Slide at Note-on, Note-off

When checked, apply pitch slide at note-on or note-off.

For percussion sounds, it may sound more natural without pitch slide.


Delay section provides parameters for feedback and delay time tuning.

Cross Feed

Amount of cross feedback between delays.

Higher value of Cross Feed adds more cross feedback, and harmonics become more complex.


Amount of feedback of FDN.

Feedback is used to change the length of sound. Oscillation can also be suppressed by decreasing Feedback.


Switch the delay time multiplier between string modes and circular membrane modes.

When Shape is 0, the multipliers use string modes and it becomes 1, 2, 3, and so on. When Shape is 1, the multipliers use circular membrane modes and it becomes 1, 1.59, 2.13, and so on.


Modulation section provides parameters related to self-modulation of FDN.


Amount of modulation to delay time by the absolute amplitude of feedback signal.

When Amount is not 0, the pitch might drop like tom tom.

Interp. Rate

Slew rate of delay time modulation per sample.

Higher Interp. Rate means more modulation, but also increases the risk of oscillation.

Max Ratio

Maximum of modulation represented as a ratio to resting delay time.

For example, when Max Ratio is 0.3, and resting delay time is 1.0, the maximally modulated delay time becomes 0.7.


When lit, it enables modulation envelope.

Modulation envelope decreases Interp. Rate through time to suppress oscillation. Recommend to always turn on for percussion sounds.

Sustain [s]

Sustain time of modulation envelope. Lengthen the sustain time tends to be more unnatural sound.

Release [s]

Release time of modulation envelope. When oscillating, shorten the release time might result in more natural sound.


Random section provides parameters for randomization for each note-on.


Seed value of random number sequence.

Changing Seed also changes the feedback matrix of FDN, and it changes the texture of cross feedback.

Matrix Rnd.

Ratio of randomization to the feedback matrix of FDN.

Overtone Rnd.

Maximum of random number that added to delay time multiplier.


Filter section provides parameters to tune the filters inserted in the feedback path of FDN.

LP Cut [Hz], HP Cut [Hz]

Cutoff frequency of lowpass (LP) or highpass (HP) filters.

Lowpass is actually highshelf with the gain fixed to 0.5 (~= -6.02 dB). It is labeled as lowpass on the interface because it felt more intuitive.


Q factor of lowpass (LP) or highpass (HP).

Q factors don’t change the output sound that much. They can be ignored unless fine tuning is required. That said, following 2 recipes might be useful to suppress oscillation in some cases. Both reduces low frequency of the output sound.

Change Log

Old Versions


MembraneSynth is licensed under GPLv3. Complete licenses are linked below.

If the link above doesn’t work, please send email to

About VST

VST is a trademark of Steinberg Media Technologies GmbH, registered in Europe and other countries.