Black Corporation Deckard's Dream Expander - User Manual

Deckard’s*Dream*Expander*FAQ*and*Build*Guide.**
DRAFT*V1.5**
What*Does*the*Expander*do?*
The Expander provides both MIDI control changes and/or audio effects, to any sources plugged in.
Effects:
1) Ring'Modulator:'Audio'Only'
2) Tremolo/Chorus:'Audio'Only'
3) Delay:'Audio'Only'
4) Reverb:'Audio'Only'
5) Sustain'I'&'II:'MIDI'Only'
MIDI*
The'Expander'receives'across'ALL'(1-16)'MIDI'channels,'and'outputs'only'on'the'channel(s)'it'receives'signals'on.'Example:'If'your'controller'is'
sending'on'channel'4,'the'Expander'will'receive'all'messages'on'CH4,'and'send'only'on'CH4.'If'your'controller'is'set'to'2-16'for'MPE,'the'Expander'
will'send'out'using'corresponding'channels'2-16.'
Audio*
The'Expander'takes'any'2'audio'sources'and'combines'them'into'a'single'audio'signal'for'effects'processing.'Balancing'the'audio'levels'must'be'
done'before'input'into'the'Expander.'
*
How*do*I*update*the*firmware?*
Firmware'for'the'MCU'cannot'be'updated.'However,'the'3'main'audio'effects'are'controlled'by'individual'SPIN'FV-1'circuits,'and'can'be'augmented'
or'modified'by'customizing'the'1-8'programs'stored'on'their'corresponding'EEPROMS.'In'short,'you'can'replace'the'EEPROMS'with'your'own'
versions.'
What*does*the*MCU*do?*
The'MCU'takes'4'inputs:''
• MIDI'
• High'or'Low'signal'from'the'Sustain'I&II'switch''
• 0'to'3.3V'from'the'Sustain_Level'slider'
• DL_Time'signal'from'the'Delay'Time'Slider'
'
The'MCU'provides'3'outputs:'
• A'CLK'signal'for'the'Delay'effect.'This'is'used'to'clock'the'SPIN'FV-1'circuit'based'on'the'setting'of'the'Time'slider'input.'This'is'why'this'IC'
does'not'use'an'external'timing'crystal'like'Reverb'and'Tremolo/Chorus'do.'
• The'Gate'signal'that'is'generated'from'the'MIDI'input'
• MIDI'Control'Change'messages'(CCs)'are'generated'from'the'settings'of'the'Sustain'Level'switch'and'Slider.'
What*about*all*the*sliders,*can*I*save*patches?*
*
Unlike'the'DD'synth,'where'slider'values'are'stored'digitally'for'patch'development'and'recall,'and'then'converted'back'to'an'analog'signal'or'
voltage,'the'sliders'on'the'Expander'are'used'entirely'as'an'analog'signal'or'voltage.'You'can’t'save'settings'for'patch'development'or'saving.''
How*do*I*hook*up*the*Expander*to*my*DD?*
There'are'several'ways:'
'
1) If'you'want'to'use'the'Sustain:'
a. Controller'MIDI'Out'->'Expander'MIDI'In'
b. Expander'MIDI'Out'to'DD'MIDI'In'
c. DD'Audio'Out'to'Expander'Audio'In'
d. Expander'Audio'Out'to'Mixer/Amp'
'
2) If'you'just'want'to'use'Audio'effects:'
a. Controller'MIDI'Out'->'DD'MIDI'In'
b. DD'Audio'Out'to'Expander'Audio'In'(1)'
c. Another'synth'Out'to'Expander'Audio'In'(2)'
d. Expander'Audio'Out'to'Mixer/Amp'
Or'even:'
a. Controller'MIDI'Out'->'Expander'MIDI'In'
b. Expander'MIDI'Out'to'DD'MIDI'In'
c. DD'Audio'Out'to'Mixer'Line'In'
d. Mixer'Aux'out'to'Expander'Audio'In'(patched'as'an'external'effects'send).'
e. Expander'Audio'Out'to'Mixer'Line'In'(Patched'as'en'external'effect'receive).'
'
'

Summary

Deckards Dream Expander Functionality

Expander Capabilities

Provides both MIDI control changes and/or audio effects to any plugged-in sources.

MIDI Channel Operation

Receives across all MIDI channels (1-16) and outputs on the channels it receives signals on.

Audio Source Combination

Combines any two audio sources into a single audio signal for effects processing.

Firmware and MCU Information

Firmware Update Possibility

The MCU cannot be updated, but audio effects controlled by individual circuits can be customized via EEPROMS.

MCU Input;Output Signals

Details MCU inputs (Sustain/I&II switch, Sustain_Level, Delay Time slider) and outputs (Delay effect, MIDI input signal).

Build and Watch Points

Power Circuit Installation

Ensure IC2 is installed for the -5V power rail before connecting the Card Board to the motherboard.

Ground Separation

Grounds are separated but joined at R2 (0 Ohm resistor) on the Card board.

Power Connector Wiring

Wire the power connector between the +Rail of the supply and the fuse to bridge for power.

Fuse Selection

Use a 750mA to 1 Amp rated fuse for the DC/DC converter, limited to a maximum of 1.5 Amps.

Slider Pin Soldering

Slider pins require careful soldering due to partial cuts; use flux for easy solder flow.

MIDI and Audio Jack Soldering

Soldering MIDI/Audio jacks can be challenging due to solder mask or small pads; ensure sufficient heat.

Audio Signal Processing

Balanced Single Source (SIG)

Combines audio sources into a balanced signal (SIG) for the MC1 (IC4) input.

Oscillator Signal (REF)

An oscillator (CEM3340, AS3340) provides a sine wave (REF) for modulation.

Modulation Control

Sliders control frequency, modulation level, and EG effect on the modulated signal.

Envelope Generator (EG)

EG circuit takes gate signal and outputs envelope profile, controlling modulation amount.

Ring Modulator and Sonic Multiplier

Ring Modulator (RM) Controls

RM controls for Attack, Decay, Sustain, Release are heard when the Depth slider is moved.

Modulation Slider Function

Sliding the Modulation slider increases modulation frequency from 0 to about 200Hz.

ADSR Enhancement

Attack, Decay, Sustain, Release are enhanced by a slider, enabling MIDI messages.

Signal Path Test

Test signal path by connecting sine and triangle waves to specific pins.

Ring Modulator Response

Ring Modulator should only respond with REF signal when an audio signal is present.

LF Trim Adjustment

Adjust LF trim to set Sine wave and Triangle wave to about 200Hz.

BUILD Issues, Mods, etc.

MIDI Thru BOM Changes

Reduce R160 to 51 Ohms and R167/R166 for proper MIDI device operation.

Digital Noise Reduction

Address digital noise from Schmitt Trigger IC35 proximity to analog signal by checking tolerance.

Noise Troubleshooting Steps

Steps to reduce noise include checking solder joints, lead cutoffs, and signal path connections.

Shielded Cable Connection

Connect shielded cables to resistors R153 & R157 as shown in the diagram.

Black Corporation Deckard's Dream Expander Specifications