Revision as of 22:38, 27 December 2018

Korg Monotron Eurorack Mod

Participants	Dennis
Skills	Soldering
Status	Planning
Niche	Electronics
Purpose	Instrument
Tool	No
Location
Cost
Tool category

Korg Monotron Eurorack Mod

Monotron PCB Front.jpg {{#if:No | [[Tool Owner::{{{ProjectParticipants}}} | }} {{#if:No | [[Tool Cost::{{{Cost}}} | }}

What

The idea is to make a eurorack module out of the Korg Monotron synthesizer. The Monotron synths are extremely hackable, Korg released the schematics and a lot of people have published mods. I have the original Monotron. I want to be able to reuse the existing pots and microswitch, so they will stick through the faceplate.

Todo

Remove battery terminals from PCB
Design and build a board with the desired in- and outputs and controls, probably on protoboard (called I/O board from this point on)
Build a simple board for powering the module (called power board from this point on)
Design and build a faceplate
Assemble everything together and put it in a eurorack case

The I/O board

Mono jack inputs

See http://electro-music.com/forum/phpbb-files/monotron_mods_181.jpg for connections of most of this.

Pitch CV in

Controls the pitch of the VCO.

Gate in

Can turn the sound on and off, most probably influencing what's coming out of the Audio out only, not the VCO out.

Cutoff CV in

Controls the cutoff frequency of the filter.

LFO rate in

There is a pad on the Monotron PCB called rate.

Mono jack outputs

Audio out

VCO out

Connect directly to Monotron PCB, pad is marked VCO.

LFO out

Connect directly to Monotron PCB, pad is marked LFO.

Controls

Switch

Toggles pitch tracking of the filter cutoff frequency

Pitch CV tune pot

Cutoff CV amount pot

Adjusts the amount of influence the CV has over the filter cutoff.

Links

@@ Line 9: / Line 9: @@
 }}
 = What =
-The idea is to make a eurorack module out of the Korg Monotron synthesizer. The Monotron synths are extremely hackable, Korg released the schematics and a lot of people have published mods. I have the original Monotron.
+The idea is to make a eurorack module out of the Korg Monotron synthesizer. The Monotron synths are extremely hackable, Korg released the schematics and a lot of people have published mods. I have the original Monotron. I want to be able to reuse the existing pots and microswitch, so they will stick through the faceplate.
 = Todo =
 * Remove battery terminals from PCB
-* Design and build a board with the desired in- and outputs, probably on protoboard (called ''I/O board'' from this point on)
+* Design and build a board with the desired in- and outputs and controls, probably on protoboard (called ''I/O board'' from this point on)
 * Build a simple board for powering the module (called ''power board'' from this point on)
 * Design and build a faceplate
 * Assemble everything together and put it in a eurorack case
+= The I/O board =
+== Mono jack inputs ==
+See http://electro-music.com/forum/phpbb-files/monotron_mods_181.jpg for connections of most of this.
+=== Pitch CV in ===
+Controls the pitch of the VCO.
+=== Gate in ===
+Can turn the sound on and off, most probably influencing what's coming out of the ''Audio out'' only, not the ''VCO out''.
+=== Cutoff CV in ===
+Controls the cutoff frequency of the filter.
+=== LFO rate in ===
+There is a pad on the Monotron PCB called ''rate''.
+== Mono jack outputs ==
+=== Audio out ===
+=== VCO out ===
+Connect directly to Monotron PCB, pad is marked ''VCO''.
+=== LFO out ===
+Connect directly to Monotron PCB, pad is marked ''LFO''.
+== Controls ==
+=== Switch ===
+Toggles pitch tracking of the filter cutoff frequency
+=== Pitch CV tune pot ===
+=== Cutoff CV amount pot ===
+Adjusts the amount of influence the CV has over the filter cutoff.
 = Links =
 * http://electro-music.com/forum/topic-57134.html