protoverb - Experimental research reverb

Experimental research reverb

Protoverb: prototype reverb

A natural sounding reverb based on the concept of a room simulator. Protoverb is an experimental researchware plug-in, developed to aid our research. Download and use it for free.

Protoverb UI

Sights and sounds

Feel it in the air

What is Protoverb?

Protoverb is an experimental room simulator reverb. Most algorithmic reverbs try to avoid resonances or model the reflections of sound from a room’s walls. Protoverb does the opposite. It builds up as many room resonances as possible, modelling the body of air in the room. No need to modulate or colour the signal. The result is a very natural sounding reverberation with interesting characteristics:

  • Notes held for a longer time tend to build up resonance, as if the air takes a while to get excited
  • Multiple instruments remain distinct, without disappearing in a wash
  • When you play a short melody, the room seems to repeat a ghost echo of that melody

These properties are found in churches and large halls, but are rarely in conventional algorithmic reverbs.

To achieve this, Protoverb works with many parallel, serial and networked delays. With such a structure, no mathematical formula can make it sound right, it is down to trial and error (and luck) using random values. Protoverb generates random delay line lengths, networks and feedback strategies. If you are lucky you will find a great setting, which you can send to us.


The text box at the bottom of Protoverb’s interface contains a text string made up of two random parts. The first half dictates the network structure, strategies for spatial layout and distribution of delay taps, strategies for finding useful delay lengths and so on. The second half is a seed for a pseudo-random number generator—used to set various parameters such as the average delay length, which prime number to choose (if any) etcetera.

You can either edit the text, or randomise each part independently using the buttons below the text box.

Protoverb randomising

Random strings in Protoverb



We call Protoverb researchware, because it is free and an attempt at data mining. Instead of spending months researching and testing ourselves, we hope that our community will come up with great settings. We encourage people to share their settings and thoughts with us and each other.


Protoverb 1.0 (revision 4102)
Released December 22, 2015
Release notes

This product is a free download and does not require a serial number to unlock it.

info Linux beta note : Before downloading, please be aware the Linux versions of our plug-ins are still considered beta. While the plug-ins are stable, we are not able to provide the same level of support for these products as we do for the macOS and Windows versions. Support is provided via the Linux and u-he communities on our forum Link.   CLOSE


Apple logo Mac OS X 10.7 or newer
Windows logo Windows 7 or newer
Linux logo Linux

  • 1GB RAM, more recommended
  • 50MB free disk space
  • 1000 × 600 or larger display
  • Modern CPU (Sandy Bridge or newer recommended)
  • Host software


Protoverb is not a standalone product, it requires host software. Protoverb is compatible with nearly all DAWs.

Available as Audio Units (AU), VST2, AAX (Pro Tools 10.3.7 or later) plug-ins with 32-bit and 64-bit versions.

Downloads for Protoverb

Try the latest builds of Protoverb, which include improvements and bug fixes. Note: these are stable, but still beta versions.

Older Protoverb installers are in our release archive (for legacy systems).