Announcing Cocteau, a Mod PCB for the YOCTO 808 Clone

Published on Apr 3, 2017 effegee7

Update: you can sign up for the kit here. You can reach Autonomik Circuits at autonomikcircuits@gmail.com.

Taking the 808 to a whole new level in tweakability. Full details further below. First the playlist for the videos above:

1. Cocteau demo (groove + mods)

"Cocteau (by Autonomik Circuits)-- overlay mod PCB for YOCTO v1.0 analog drum machine

Cocteau PCB fits over the top of the YOCto main PCB, adding 34 pots and 24 switches to the front panel to modify the original 808 sounds, plus it adds a second RS-CL and MA circuit hardwired to the YOCTO's Trig-1 and Trig-2.

This video demos the following:

- CH Decay (short)
- BD Tune (low)
- CP Filter is turned high and clap density increased to mostly eliminate the Clap sound, leaving just the Reverb
- CB Long Decay, OSC's tuned
- LT Reverb Off & On
- CL-2 2nd switch (the RS-CL DPDT switch split into two SPDT's) activated to create a CR-78-type RS sound

Front panel is laser-cut resin prototype of enclosure to be made by Kacper Pawluk"

2. Cocteau- RS-CL 2 + CP mods

"This video demos the additional RS-CL 2 voice on the Cocteau PCB, as well as some of the CP mods

The DPDT slide switch between the RS and CL sounds of the Cocteau's RS-CL 2 circuit has been split into individual SPDT switches to allow for variation of the CL sound as follows:

Both switches down = RS sound
Both switches up = CL sound
Left up, right down = CL sound altered s\to sound more like striking a glass bottle, not a wood block
Left down, right up = CL sound reminiscent of the CR-78 RS sound(?)"

3. RS-CL 2 & MA-2

"This video demos the additional RS-CL 2 and MA-2 voices on the Cocteau PCB, allowing for simultaneous sequencing of RS & CL and CP & MA sounds.

The DPDT slide switch between the RS and CL sounds of the Cocteau's RS-CL 2 circuit has been split into individual SPDT switches to allow for variation of the CL sound as follows:

Both switches down = RS sound
Both switches up = CL sound
Left up, right down = CL sound altered s\to sound more like striking a glass bottle, not a wood block
Left down, right up = CL sound reminiscent of the CR-78 RS sound(?)"

4. Cocteau Roll Call

SoundCloud demos:

Full details via effegee:

"Cocteau is placed over the YOCTO's front panel PCB to add 34 pots and 24 slide switches for modification of the YOCTO drum voices. Cocteau also adds duplicate RS-CL and MA circuits (RS-CL 2 & MA-2) hardwired to YOCTO's Trig-1 and Trig-2 switched jacks, allowing simultaneous sequencing of RS & CL and CP & MA (so you don't have to choose one sound at the expense of the other).

Cocteau ships as a DIY kit with PCB and hard-to-find/special-order parts (slide switches, 2M(B) pots, etc.), with a Tayda BOM for the Alpha pots and a Mouser BOM for all other parts. Build instructions will be provided.

Installation requires desoldering of some components (mostly resistors) and cutting of a few traces.

Cocteau is designed to allow the user to modify the existing circuits while allowing easy, realtime return to the original 808 sound. For example, the BD Tune pot functions only when the adjacent switch is activated; when deactivated, BD Tune returns to the original value.

Cocteau is also designed to fit within the existing panel clearance using low-profile pots, switches and connectors. A metal enclosure for the YOCTO + Cocteau will be available from Kacper Pawluk, who has already designed the front panel. A laser-cut resin panel, fabricated from his design, has been tested and fits perfectly.

Finally, there will be an expansion port on the back panel of the enclosure, connected to Trig-3 of the YOCTO sequencer, for installation of swappable drum modules available for future purchase.

Cocteau list of mods:

Pots (x34):

BD Tune*
BD Envelope*
BD Xtra Decay
SD Tune 1*
SD Tune 2*
SD Filter* (Snappy)
SD Decay* (Snappy)
LT Reverb
LT/LC Decay
MT Reverb
MT/MC Decay
HT Reverb
HT/HC Decay
RS Tune 1*
RS Tune 2/CL Tune*
RS Filter
CP Reverb
CP Filter
CP Density
CB Tune 1* (OSC 1 Tune)
CB Tune 2* (OSC 2 Tune)
CB Filter
CB Decay (normal)
CB Decay (long)
OSC 1 & OSC 2 trimmers (moved from underside of YOCTO PCB)
OH Filter
CH Filter
CH Decay
Metal Tune* (OSC 1 & 2 of CB/CY/OH/CH)
4 extra pots (+ extra pads) for user custom mods
RS-CL 2 Level
MA-2 Level
(Pots with * have an adjacent slide switch to change between original value resistor/cap and mod pot, allowing user to quickly switch back to authentic 808 sound.)

Additional slide switches:
LT Reverb Off
MT Reverb Off
HT Reverb Off
CP Normal Filter <--> Low Filter (x2)
CP Density <--> CP Delay
CB Decay (Normal) <--> CB Decay (Long)
MT Decay (an extra switch needed to accompany original MT-MC slide switch)
RS 2 <--> CL 2 (x2)
+ additional switches for user custom mods

Availability: Cocteau will be ready to ship about 8 weeks after the initial run list is finalized, which is the time needed to receive the special-order parts. Post here or PM me if you you are interested in a kit.

Pricing:
The projected price is $145/kit, plus shipping & handling from the U.S.

What's included:
- Cocteau front panel PCB
- (18x) high-quality 500-series SPDT switches
- (7x) make-before-break (MBB) DPDT switches
- (4x) Alpha 2M(B) pots
- 1 meter shielded stereo cable
- (1x) SK30A transistor (for RS-CL-2 circuit)
- Plastic sheet (to shield between YOCTO main PCB and Cocteau)

The Tayda BOM for the pots is around $18 USD and Mouser BOM, about $40.

Other supplies needed:
- an MTA hand tool ( http://www.mouser.com/ProductDetail/TE-Connectivity/59803-1/ ) and some 24 AWG wire (or you can use pre-assembled PH 2.0 connectors, though I prefer the MTA connectors for reasons that will be clear in the build instructions)
- Brand new, sharp (yes, sharp) clippers. I recommend these: Plato 170, http://amzn.to/2ovrylt
- Desoldering braid or a desoldering gun, such as a Hakko FR300-05/P (I use the discontinued Hakko 808) or ZD-915 desoldering station (shown here on a NAVA: https://youtu.be/v0iA_b0WTDg)
- a blade, such as an Xacto knife "