DDRM rev.2 guide

Last updated: Jul 04, 2022

Page History:

Date	Autor	what
May 9. 2018	LED-man	DDRM 2.0 guide initial
Oct 25. 2018	LED-man	BOM added
July 30 2019	LED-man	software
Feb 2020	LED-man	BOM pricing
June 2020	LED-man	structure
Oktober 2021	LED-man	BOM 6N138 to 6N139

Deckard's Dream Synthesizer

Hi all, this is the place to find the latest building documents for Black Corporation's Deckard's Dream polyphonic synthesizer.Currently, this project is at rev 1.0, PCB's are currently being released to builders. (18.Oct. 2017) and are being constructed.A new PCB version rev. 2.1 is planned and the release is planned for July 2018, this page is only for rev.2.x

Product Info:the Deckard's Dream product is available as Build to order and DIY KIT Version, both released in 2017.Its also known or coined as the "DDRM".The difference in the DIY KIT and assembled (Build to order) are:

the component format, the DIY KIT is mostly THT, the build to order synth is mostly in SMT.
The case size is not as deep for the build to order as it is for the DIY.

Note: Although the DIY has most of the SMT devices pre-installed onto the PCBs, there are over 675 SMT decoupling capacitors (0805) and one small (SOIC8) power switch device that MUST be installed by the builder, in addition to the through hole componentsA addional 1U expander is planned - release in 2018Examples of Presets and voices: https://soundcloud.com/deckardsdream

Technical Specs:

Click here to expand...

Synthesizer features

8-voice polyphonic analogue synthesizer
Fully analogue signal path
2 synthesis layers per voice
256 presets

Layer architecture

VCO with square, saw and sine waveforms
PWM with sine-wave LFO
Manual PW (50-90%)
12dB HP and LP discrete filters with separate resonance controls
ADSR filter envelope with adjustable initial and attack levels
ADSR VCA envelope
Velocity and aftertouch controls for filter brilliance and volume levels

Master controls

Global coarse/fine tune
VCO2 detune
LFO with sine, saw, ramp, square and stepped random waveforms
LFO destinations: VCO, VCF, VCA
Crossfade between layers 1 and 2
Global filter brilliance and resonance control for additional resonance
Polyphonic aftertouch destinations: LFO speed, LFO to VCO amount, LFO to VCF amount, filter brilliance, volume level
Keyboard tracking adjustment for VCF and VCA

Controls

MIDI/MPE with polyphonic aftertouch
Polyphonic pitchbend
Unison
MIDI over USB
128 factory and 128 user presets
Alternate scales and tunings
Software editor by Spektro Audio

Display

128×64 OLED display

Connectors

DC input jack (9-24V)
External modulation input jack (1/4″)
Expander jack (DIN5)
USB jack (type B, device/host)
MIDI IN jack (DIN5)
MIDI THRU jack (DIN5)
AUDIO OUT LOW jack (1/4″)
AUDIO OUT HIGH jack (1/4″)

Physical specifications * the DIY VERSION is different for the depth and weight

19″ 4U rack-mount
Width: 483mm / 19″
Height: 178mm / 7″
Depth: 200mm / 7.8″
Weight: ~ 4.8 kg / 10.6 lbs incl external PSU brick.

Current identified Errors/Omissions/Errata:

Date	Location	Identified issue	Resolution
Oktober 2021		BOM failure	change the 6N138 to 6N139 or you run in stucking notes

Assembly Voicecard Guide: (credits to Trey Petty)

DDRM Voice Card Guide.pdf updated 04 July 2022

the 10K resistor diagram, was incorrectly indicates the R185 position.

User Manual

Deckards_dream_manual_130.pdf

Bugtracker

further bugs, issues, problems are reported here (here are user reported issues due to soldering failures or other issues reported too)https://github.com/ffont/ddrm-issues/issues
Deckard's Dream Home and Store: http://www.deckardsdream.com

Current BOM (last version valid 2.1.4 - Sep.2019)

DD-BOM-REV2.1.4.pdf DD-BOM-REV2.1.4.xlsx. change the 6N138 to 6N139 !!

Shared Mouser Basket: https://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=15f70d6513 (made by me - 09/2019 from 2.1.4 BOM, not checked by me - but the amount of parts looks ok)
Ultravox reply: "The cart doesn't include items that the BOM says are sourced from eBay, Small Bear, synthcube, etc."About partsourcing: check the price for the next price break ( 3 resistors are more expensive than 10)for EU users: order from www.TME.eu standard parts, its cheaper as mouser
Prices incl. 19% VAT(Germany) and shipping (combined)Mouser 630€
OLED 10€
bracket 15€
spacers 25€
screws 10€
psu ext. 20€
v2164 x35 120€
CEM3340 x16 250€ or AS3340 120€
poti 100K 1x 2€
slidercaps set 12€
pushbuttons x5 5€
noise PIC x1 10€t. TOTAL : 1.111€
plus DIY PCB SET 999USD netto (no VAT/TAX calculated)plus Case 270USD netto (no VAT/TAX calculated)

OLED Display:

make sure your OLED folow this pinout VCC-GND-SCL-SDA, very often shows the shop the correct pinout but deliver another type.AND short the pins on the display side (where the Frontpanel is) to prevent shorts to the Frontpanel.if you cant source the correct display (pin) use restore legs and bend they - use cable shrink tube to protect this for shorts
(please note the version and changes at the bottom of the sheets. Also see Errors/Omission and Errata above)