While trying to fix a broken TR-909, I came up with a versatile DIY analog percussion synth circuit that combines the punchy character of the 909 with the metallic textures of FM synthesis. It comes with four different modes:
• TR-909-style kick/tom
• Metallic bell/gong
• TR-606/TR-808-style cymbal
• FM cymbal
Build your own as a DIY eurorack kit: https://www.ericasynths.lv/shop/diy-kits-1/edu-diy-fm-drum/
Get LABOR here: https://www.ericasynths.lv/shop/diy-kits-1/edu-diy-labor/
Get LABOR Scope here: https://www.ericasynths.lv/shop/diy-kits-1/edu-diy-labor-scope/
Support the channel...
... through Patreon: https://www.patreon.com/moritzklein
... by building my other DIY kits: https://www.ericasynths.lv/shop/diy-kits-1/
Simulation in CircuitJS: https://tinyurl.com/28xlch23
Join my Discord community: https://discord.gg/KCwpyAsFpb
This wildcard drum synth is the final drum voice in my DIY drum machine series (for now). If you want to build along, here's the bill of materials:
BILL OF MATERIALS
RESISTORS
1M x4
470k x3
330k x1
200k x1
100k x15
68k x1
51k x2
47k x1
39k x2
33k x3
18k x1
10k x7
5k6 x1
4k7 x1
2k x2
1k x1
470 x1
47 x1
CAPACITORS
1 uF x1
470n x1
15 nF x1
10 nF x1
5.6 nF x1
2.2 nF x1
470p x2
330p x1
SEMICONDUCTORS
1N4148 (small signal diode) x18
BC548B (NPN) x8
BC558 (PNP) x5
TL074 (quad op amp) x1
TL072 (dual op amp) x1
POTENTIOMETERS
2M (trimmer, W205) x1
1M (B105) x1
500k (A504) x1
250k (B254) x1
100k (A104) x2
100k (B104) x1
MISC
Switched mono jack socket x5
Single pole, double throw switch x2
Chapters
00:00 Intro & Sound Demo
01:46 Triangle VCO
05:56 Tri To Sine Waveshaper
07:17 VCA
11:20 Decay Envelope
12:28 Gate To Trigger Converter
14:00 VCO Reset
15:26 Pitch Envelope
18:44 Attack (Distortion & Click)
21:38 FM
25:00 XOR Pulse
27:36 High Pass
30:05 Decay CV
31:20 Tune CV
34:08 Final Demo & Outro