Amplitude Envelope on a Synthesizer

- -

Hello once again! I am Benson Lim from Melbourne and for the sixth and final week of “Introduction To Music Production”, I’ll give a thorough explanation of the amplitude envelope. I’ll cover the following amp envelope configurations: Switch, Percussive, Damped percussive, Sustaining (blown or bowed), and Quirk. The screenshot you’ll see below comes from Apple Mainstage 3 with the “ES 1” synthesizer. On the bottom right, you’ll see the ADSR configuration.

What is an envelope? Envelope is a set path everytime a key is pressed. Normally the sound goes up, and then down, stays for a while and fades out. On a synthesizer, an envelope is controlled by four paramters. They are “Attack Time”, “Decay Time”, “Sustain Level” and “Release Time” or ADSR for short.

ADSR *the graph above was taken from Loudon Stearns’ Introduction To Music Production, Week 6 – Amplifiers

Switch Envelope

You can achieve this by setting Attack to 0, Decay Time which does not matter but set it to very low, in this case 0, Sustain Level to 100% and Release Time to 0.


The switch envelope functions like a hammered organ does. Once you stop pressing the key, it’ll stop immediately. Here’s a sample sound of how it’ll sound like.

On some synthesizers, you might get a click sound. To remove the click sound, add abit of attack and release time. You can increase the attack time and you’ll get a swelling kind of sound. This emulates a reverse sound very well.

switch no click

Percussive Envelope

In the lecture, Loudon’s configuration looks exactly the same like the switch envelope. I made a few modification to my setting because the percussive envelope is good in emulating the string or brass instruments which means, I’ll need to increase my release. Why? because like the real instrument, they’re adding energy to the note as the note continues on.


And here’s a sample of a percussive sound.

Damped Envelope

To get the damped envelope, set everything else to 0 and set the “Delay Time” to 10-80%. The damped envelope simulates a piano. When you press a key, you’ll get an initial attack and then the note decays naturally.


And here is a sample of the damped sound. If you want a full sound irregardless of the length you press, set the “Release Time” the same as the “Delay Time”.

damped release

Sustaining (Blown or Bowed) Envelope

To get the blown or bowed envelope, set your “Attack Time” to 0-10%, “Decay Time” to 50%, “Sustain Level” to 50-90% and “Release Time” to 50%. I am aware that these settings are quite different from the one shown in the lecture, but setting the 0-10% to decay and release time doesn’t give me the sound that I wanted.

This envelope is useful to emulate the sound of a blown or bowed instrument like the violin. Like the violin, you’ll have a sudden attack, and then a sustain sound. blown And here’s a sample of the blown sound.

Quirk Envelope

This envelope is something that Loudon found by accident. It does not emulate any instrument but it has an interesting sound. If you press 1 note, you’ll get a beep. Press 2 notes, and you’ll get a long release. This happens because the release phase starts when you release the key.


And here’s a sample of the quirk sound.

Thanks again for spending time to read this simple demonstration and I hope that you enjoy reading it as much as I enjoy writing it.