flight of harmony Eurorack Module ~rev1.
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 Specifications Supply Voltage Supply Current ±12VDC IV+= 51mA (max draw @ ±12V) IV-= -21mA 10Vp-p Max. Input Voltage (@ ±12V) 6Vp-p Max.
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 amplifier (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.
Controls Rate: This controls the delay clock rate, which in turn controls how fast the delay steps through its memory array and thusly the amount of delay. Clockwise rotation increases the rate (which decreases the delay time), counter-clockwise decreases the rate (which increases the delay time). Feedback: Controls how much of the delayed signal is fed back into the delay cell. Feedback is what creates a reverberation or echo sound – multiple repetitions of an acoustic event.
fig.1 Jacks The jacks are grouped by the type and direction (into or out of the module) of the relevant signal. The VCA jacks are just labeled “VCA”, as the function of each is already described by what row they are in. CV in Rate: Quirk warning: Rate CV behavior is inverted. Negative increases rate, positive decreases. If that bugs you too much, just think of it as the delay CV input and the issue magically disappears! Positive increases the delay, and negative decreases the delay.
FBCV RTCV RTPTWPR CLKOUT SPARE2 RTCV(R) FBCV FBWPR(R) RTEPT3 VCACV(R) VCACV GND GND V- VCVACV SPARE3 FBIN VCAIN CLNDELMIX MIXVCA INVCLN DELFB V+ MIXOUT DELMIX VCAOUT IN (R) IN CLNMIX DELOUT Other connections Power: The power connector header is a 2x5 shrouded box header which accepts the standard Doepfer power cable. This header style is polarized, meaning the connector can only be inserted one way, to prevent connecting the power backwards and damaging the unit.
FBWPR(R) FBCV RTCV(R) FBCV RTEPT3 RTCV RTPTWPR VCACV(R) GND CLKOUT VCACV VCVACV V- SPARE2 GND SPARE3 VCAIN FBIN INVCLN MIXVCA DELFB Top row, left to right: V+ MIXOUT DELMIX CLNDELMIX IN DELOUT VCAOUT IN (R) CLNMIX The descriptions will be minimal, if they aren’t enough for you, you should not be messing with them. Bottom row, left to right: IN(R) Signal input (J) CLNMIX con.
Stuff There is a lot of discussion about the Sound of Shadows on the Muffwiggler forums, come check it out! People have posted some excellent demos on there. I haunt the forums as well, and new things are posted there long before they hit the f(h) website. http://www.muffwiggler.com/forum/index.php A big thank you to those who have sent in suggestions and comments, keep them coming! Send samples to: samples@flightofharmony.com Comments, suggestions, complaints to: flight@flightofharmony.
f(h) 8/8
