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Specications
Supply Voltage
±12VDC
Supply Current (max draw @ ±12V)
IV+= 51mA IV-= -21mA
Max. Input Voltage (@ ±12V)
10V
p-p
Max. Output Voltage
6V
p-p
Input & Ouput (I/O) coupling Direct*
Output Impedance 1kΩ
Control Voltage (CV) inputs
±V
supply
CV input coupling Direct
CV input impedance
100kΩ
* I/O jacks are direct-coupled. The Delay circuit itself is not. A DC signal at the input will be
available at the Clean, Mix, and VCA outputs, but not available at the delay output.
Components
1
Assembled Sound of Shadows digital delay module
1
DC power cable – 9” Ribbon cable (Doepfer standard)
4
M3x0.5x5mm Stainless-Steel machine screws
4
M3 Nylon washers
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What is it?
The Sound of Shadows (SoS) is a voltage-controlled (VC) digital delay
module based around the PT2399 echo IC1 from Princeton Technology – which
was, by the way, originally designed for Karaoke equipment. The SoS is essentially
two separate modules: a delay and a voltage-controlled amplier (VCA). The
focus of the SoS was the delay while the VCA was thrown in because half of an
LM13700 IC was unused, so the VCA is very basic.
As with all f(h) products, the SoS was engineered towards maximizing
functionality while keeping cost as low as possible. If some aspects of the unit
seem awkward, it is most likely due to this. The goal is to make unique, useful,
enjoyable, and affordable instruments, not just hoover2 out your bank account.
And remember: every instrument has its quirks and unexpected aspects,
so RTFM3! All the way through! Specic quirks are mentioned in the description of
the particular feature they apply to, so please read this through before emailing!
DELAY
In Out
Input
x -1
x -1
In Out
FEEDBACK
Clean
out
Mix
out
Mix
Delay
out
Insert
jack
EXT
VCA
out
In Out
VCA
VCAIN
jack
EXT
Sound of Shadows flowchart
Feature summary:
Delay
VC delay rate•
VC feedback level•
Signal input•
Clean, Delayed, and Mix •
outputs
Feedback loop insert jack•
VCA
Input breakjack•
CV input•
Output•
The 30-pin header on the back of the module is for the SoS expansion
module, currently in development.
1) Integrated Circuit
2) Hoover is a company that manufactures vacuum cleaners.
3) RTFM = Read The F*cking Manual!
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