flight of harmony The Sound Of Shadow User manual

KIT
flight of harmony
Digital Delay Effect
Eurorack Module Kit
~rev1.0~

Rate
Mix
Feedback
Input
VCA CV
VCA
FeedbackRate
dry wet
VCA
VCA
VCA
Delay
SOS-K
Clean Mix
Insert
Input
CV in
output
Signal in
f
(h)
the Sound of Shadows
Specifications
Supply Voltage ±12VDC1
Supply Current (max draw @ ±12V) IV+= 51mA IV-= -21mA
Max. Input Voltage (@ ±12V) 10Vp-p
Max. Output Voltage 6Vp-p
Input & Ouput (I/O) coupling Direct2
Output Impedance 1kΩ
Control Voltage (CV) inputs ±Vsupply
CV input coupling Direct
CV input impedance 100kΩ
Number of pieces (nuts & washers of
pots & jacks not counted) 159
Kit Difficulty Advanced
1 Has been tested and performs well with supply voltages from ±9VDC to ±15VDC.
2I/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.
SoS-K v1.0 instructions Oct. 2019 — p.2/13 www.flightofharmony.com

(1) Front Panel
(3) PCB- Main, Potentiometer, Jack
(3) Resistor Card
(1) Semiconductor Card
(1) Capacitor Card
(1) Hardware bag
(1) 9” ribbon cable
(1) 2x5 box header
(1) 2x5 IDC socket connector with strain relief
(1) 2x8 IDC socket connector with strain relief
(4) M3x0.5 eurorack mounting screw
(4) M3 nylon washer
(4) 1x7 pin header (see note)
(4) 1x7 socket header (see note)
(4) Nylon PCB Standoff (see note)
(1) Potentiometer bag
(2) A100k Potentiometer (Input, Insert)
(4) B100k Potentiometer
(6) Washer
(6) Nut
(6) Knob
(1) Jack bag
(10) 3.5mm TS jack
(10) Washer
(10) Nut
(1) Reference manual (this thing)
NOTE: This kit is designed to be able to use jacks and/or pots
with varied heights from different manufacturers. Lengths of PCB
standoffs and pin headers will vary depending on contents. The
Potentiometer PCB gets the (2) longer standoffs and (2) longer pin
headers.
SoS-K v1.0 instructions Oct. 2019 — p.3/13 www.flightofharmony.com
Contents

SoS-K v1.0 instructions Oct. 2019 — p.4/13 www.flightofharmony.com
What is it?
The Sound of Shadows (SoS) is a voltage-controlled (VC) digital delay
module based around the PT2399 echo IC1from 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 is the delay; 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 hoover2out your bank account.
Remember: every instrument has its quirks and unexpected aspects, so
RTFM3all the way through! Specific 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
1) Integrated Circuit
2) Hoover is a company that manufactures vacuum cleaners.
3) RTFM = Read The F*cking Manual
Overview (taken from SoS-E manual)

SoS-K v1.0 instructions Oct. 2019 — p.5/13 www.flightofharmony.com
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. Clockwise rotation increases the amount fed
back, and thus the number of repeats, counter-clockwise decreases the amount.
The nominal operating area is between 6:00 and 9:00 during normal
usage. More than this will set up a self-propagating feedback cycle that will
quickly get out of hand.
Insert: This is the attenuator for the feedback loop insert jack. The
jack is situated between the delay cell output and the feedback cell input.
The feedback cell input is calibrated for the output of the delay cell, which
is around 1.5Vp-p maximum, and most standard signals inserted here will
overload the feedback cell unless attenuated, hence the Insert attenuator.
Turn clockwise to increase the signal level, counter-clockwise to attenuate.
When not using the Insert jack, it is recommended to keep this control
turned fully clockwise, to the maximum position. Otherwise, you are attenuating
the output of the delay cell, which will affect everything else further down the
signal path.
Input: This is the input level control. Just like a volume knob – clockwise
increases level, counter-clockwise attenuates the signal level.
Mix: Controls the mix between the Clean and Delay signals at the Mix
jack.
VCA: Controls the VCA output level. Standard behavior with a minor
quirk: this control will not fully attenuate the output, but a negative CV applied to
the VCA CV input will bring the level much further down. It was either this or add
another IC + associated components to the PCB and jack the price further up.
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.
Overview (cont.)

SoS-K v1.0 instructions Oct. 2019 — p.6/13 www.flightofharmony.com
Feedback: This works
normally, positive CV increases
feedback, negative decreases same.
VCA: Same as feedback,
positive CV increases the output
level, negative attenuates it.
Signal in
Input: This is kind of
important for a delay unit: you need
a signal to delay, or else they’re
somewhat dull effects. This is the jack
where that signal is input into the delay.
Insert: This is the feedback loop insert breakjack4. Inserting a plug
here will disconnect the output of the delay cell from the input of the feedback
cell, with the inserted signal now going directly to the feedback gain cell.
One use for this is to insert an effect – or even another delay unit (yes,
they can be daisy-chained quite effectively) – into the feedback loop. To do this,
patch the Delay out into the desired effect, and the output of the effect into the
Insert jack. You may need to adjust the Insert level control (see above) for best
sound.
VCA: This is another breakjack. The input of the VCA is normalized
(normally connected to) the Mix output. Inserting a jack here breaks that connection,
enabling the VCA to be used completely independently of the rest of the module.
Output
Clean: A buffered and inverted copy of the input signal.
Delay: The buffered & scaled output of the delay cell
Mix: A linear mix of the Clean and Delay signals, the balance of which
is set by the Mix control pot.
VCA: Output of the VCA.
4) Inserting a plug into a breakjack “breaks” the default signal routing. Removing the plug restores the
default routing. In technical terms, it is a Normally-Connected (NC) switched jack.
Overview (cont.)
fig.1

SoS-K v1.0 instructions Oct. 2019 — p.7/13 www.flightofharmony.com
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.
This assumes that you are using either the
supplied cable or one manufactured by Doepfer.
Looking at the rear of the module, the negative supply (red stripe) is on the
left, positive supply is on the right (see fig.2).
Contact:
email: [e-mail]
Twitter: @flightofharmony
Drawings and designs ©2019 flight of harmony, LLC.
http://www.flightofharmony.com
We are tomorrow’s shadows...
f(h)
Overview (cont.)
fig.2

SoS-K v1.0 instructions Oct. 2019 — p.8/13 www.flightofharmony.com
PCB Assembled View

SoS-K v1.0 instructions Oct. 2019 — p.9/13 www.flightofharmony.com
Exploded View

SoS-K v1.0 instructions Oct. 2019 — p.10/13 www.flightofharmony.com
SMD Reference

SoS-K v1.0 instructions Oct. 2019 — p.11/13 www.flightofharmony.com
Control & Jack Reference
A100k
A100k

SoS-K v1.0 instructions Oct. 2019 — p.12/13 www.flightofharmony.com
Power Cable Assembly
Triangle indicates
location of red stripe.

SoS-K v1.0 instructions Oct. 2019 — p.13/13 www.flightofharmony.com
IC1 Orientation
Diode Orientation
Line/Slope Line/Slope
Pin 1
Miscellaneous
LINE
(OR) LINE