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).'
'
'