Vongon polyphrase User manual

USER MANUAL
VERSION 1.0

CONTENTS
OVERVIEW
3
FRONT PANEL
5
MONO CONNECTIONS
7
STEREO CONNECTIONS
8
CIRCUIT DIAGRAM
9
ECHO STYLES
10
GAIN MODES
11
MIDI
12
MIDI CONTROL CHANGE (CC) TABLE
12
PRESETS
13
MIDI CLOCK SYNC
14
MIDI CHANNEL
14
MIDI ADAPTER
14
POWERING
15
EXTENDED WARRANTY
15
CONTACT
15
CHANGE LOG
15
Thank you for supporting Vongon! We are a small operation based in Oakland,
California. All products are assembled and tested with care and attention in our studio.
We catalog audio and video demos of our devices on our website at
(www.vongon.com) and instagram (@vongonelectronics). Please feel free to reach out
to Ryan or Katie with any questions - [e-mail]
2

OVERVIEW
POLYPHRASE is a stereo echo and looping device inspired by early proto-digital delays
of the 1970ʼs like the Lexicon Prime Time. As sophisticated as it is easy-to-use, Polyphrase
is capable of everything from rich, dubby rhythmic repeats, to metallic resonant flanges.
It is unique in being able to generate loops as long as 22 seconds, opening up a new
palette of sonic possibilities for the avant-garde, ambient, or adventurous musician.
Polyphrase features two independent sliders for le and right delay times that can be
locked into an infinite feedback loop which will produce an ever-changing sample of
audio as each channel overlaps with another. This makes Polyphrase a tool for
exploration capable of achieving the same kind of harmonic oscillation found on Steve
Reichʼs seminal tape piece “Piano Phase”.
The time knob interacts with the le and right faders by providing nine different
maximum delay times starting at 85 milliseconds, and doubling in value as the
parameter is increased up to 22 seconds. Each new delay section is cross faded into the
signal path, an important design consideration that avoids any pitch shiing artifacts
and is useful for creating new and oen unexpected musical phrases when used with
high repeat settings.
Three echo styles are available, and each style configures its own dedicated routing for
the delay feedback path. “Dual stereo” provides two independent echos, and they can
either be stacked in mono, or routed out of each stereo channel. In “ping pong” mode,
each delay feeds back into the other, creating either a classic stereo ping pong sound
(with each repeat bouncing between the le and right channel), or a multi-tap delay
effect (when used in mono). The last mode is a mono delay - it routes the feedback path
to the IN R, OUT R jacks so that you can use external effects in the echoʼs feedback path.
The tone control is a bipolar equalizer (EQ) situated in the feedback path of the echo. At
12 oʼclock, the EQ has no effect on the audio. Turning the knob clockwise cuts low end -
making each repeat brighter than the previous. Turning the tone knob in the
counter-clockwise direction cuts high frequencies - it creates darker repeats, which-
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makes Polyphrase capable of achieving similar timbre to the storied analog,
bucket-brigade delays.
The echo signal can be pitch modulated with the rate and depth controls for a sine wave
style chorus / vibrato, or with a random wave for detuning effects similar to aging tape
echos.
Finally, Polyphrase has a fully featured midi input that provides tempo sync, full remote
control of all parameters on the faceplate, and access to 9 onboard user preset slots.
FEATURES
○Delay times from 5 milliseconds to 22 seconds
○Two delay lines that can be used in stereo or stacked in mono
○Infinite feedback
○External feedback path
○Tone control in the feedback path
○Echo pitch modulation with sine or random style waveform
○Tap tempo
○Midi tempo sync
○9 onboard user presets accessible via midi program change (PC) messages
○Remote control of all parameters on the faceplate via midi continuous controller
(CC) messages
○3 gain configurations for line level, instrument level, or low instrument level
○Housed in a single block of walnut, CNC routed, hand sanded & polished
SPECIFICATIONS
○141mm x 121mm x 45mm
○1/4” mono jacks
○Input impedance: 1MΩ
○Output impedance: <1kΩ
○Current draw: 200mA
○So-touch foot switches
○Buffered bypass
4

FRONT PANEL
1) LEFT OUTPUT: 1/4” jack, unbalanced signal output, instrument or line level.
2) RIGHT OUTPUT: 1/4” jack, unbalanced signal output, instrument or line level. Echo
send in “mono with external loop” echo style.
3) LEFT INPUT: 1/4” jack, unbalanced signal input, instrument or line level
4) RIGHT INPUT: 1/4” jack, unbalanced signal input, instrument or line level.
Normalled to le input. Echo return in “mono with external loop” echo style.
5) POWER INPUT: 9VDC center negative, 200mA
5

6) TONE CONTROL: EQ in feedback path of echo, turn clockwise for brighter repeats
and counter clockwise for darker
7) REPEATS CONTROL: Feedback amount for delay lines, from 0% for a single repeat
up to 110% for self oscillation and distortion.
8) DEPTH CONTROL: Depth of pitch modulation on echo signal. At 12 oʼclock, there is
no pitch modulation. Counter clockwise for sine wave modulation and clockwise for
random modulation.
9) RATE CONTROL: Speed of pitch modulation on echo signal.
10) MIX CONTROL: Balance of dry and wet signals.
11) MIDI INPUT: Type B, 3.5mm TRS input jack
12) TIME CONTROL: 9 discrete max echo times ranging from 85 ms to 22 sec. No pitch
modulation artifacts when adjusted.
13) ECHO STYLES: Reroutes the echo feedback paths.
●DUAL STEREO: two independent echos that can be used in stereo or stacked in
mono.
●PING PONG: Echoʼs feedback into each other
●MONO: Mono echo with feedback path routed to Right input and output jacks
for external processing.
14) TRIG: footswitch for tap tempo or toggles infinite mode, depending on “TRIG
FUNCTION” selection.
15) LEFT AND RIGHT SLIDERS: time control for delays that scale the delay time from
x1 to x0.05, press “SYNC” to lock both delays to the le slider.
16) BYPASS: footswitch to toggle effect on/off, buffered bypass
6

MONO CONNECTIONS
7

STEREO CONNECTIONS
8

CIRCUIT DIAGRAM
Simplified circuit diagram of the signal flow inside Polyphrase.
9

ECHO STYLES
The three echo styles reconfigure the echoʼs feedback path as shown below.
10

GAIN MODES
POLYPHRASE supports three gain configurations that make it useful with different
audio sources. By default, the pedal is in “instrument level” mode. If your input signal
is clipping or if you hear too much noise, try adjusting the mode by following the steps
below. The pedal will always remember the most recently used mode (even between
power cycles).
Note: The “line level” mode will still clip when using particularly loud audio sources. If
you hear any clipping, you should turn down the signal going to the pedal. Although,
there is no harm in clipping the pedal if that sounds good to you!
11

MIDI
Polyphraseʼs midi input provides tempo sync, full remote control of all parameters on
the faceplate, and access to 9 onboard user preset slots. See implementation details
below.
MIDI CONTROL CHANGE (CC) TABLE
When the pedal receives Midi Control Change messages on its assigned midi channel,
it will internally set parameters to the new midi value. Manually adjust the faceplate
parameter to reset the value to the physical faceplate control.
MIDI MESSAGE
PARAMETER
VALUES
CC #1
REPEATS
0-127
CC #2
TONE
0-127
CC #3
DEPTH
0-127
CC #4
RATE
0-127
CC #5
SLIDER L
0-127
CC #6
SLIDER R
0-127
CC #7
MIX
0-127
CC #8
TIME
0-8: 85ms, 9-22: 170ms, 23-37: 341ms, 38-56:
682ms, 57-74: 1.3s, 75-91: 2.7s, 92-106: 5.5s,
107-120: 11s, 121-127: 22s
CC #9
ECHO STYLE
0-43: DUAL STEREO,
44-87: PING PONG,
88-127: MONO
CC #10
SYNC
0-63: OFF, 64-127: ON
CC #11
TRIG MODE
0-63: OFF, 64-127: ON
CC #13
BYPASS
0-63: OFF, 64-127: ON
CC #14
INFINITE
0-63: OFF, 64-127: ON
CC #15
TAP TEMPO
Any CC value triggers tap
12

PRESETS
Polyphrase has 9 onboard user preset slots that can be read and written to via MIDI
PROGRAM CHANGE (PC) messages. These presets are saved between power cycles.
Example Read/Write to preset 1:
●Write to Preset 1: Adjust pedal to desired sound, send a MIDI PC# 11. That
sound is now saved into preset slot #1.
●Recall Preset 1: Send a MIDI PC#1 message, the pedal will read the sound
stored in preset slot #1 and internally reset parameters.
PRESET
READ (MIDI MESSAGE)
WRITE (MIDI MESSAGE)
1
PC #1
PC #11
2
PC #2
PC #12
3
PC #3
PC #13
4
PC #4
PC #14
5
PC #5
PC #15
6
PC #6
PC #16
7
PC #7
PC #17
8
PC #8
PC #18
9
PC #9
PC #19
13

MIDI CLOCK SYNC
Polyphrase accepts MIDI clock signals via the MIDI input jack. These messages are 24
ppq messages that can be sent via MIDI computer sequencers or from drum machines.
To enable the sending of these messages, consult the user manual for your MIDI
device. As soon as a MIDI clock signal is detected, the SYNC LED will light up and the
sliders will have no effect on delay time. You can adjust the time knob to double or half
the delay time in sync with the MIDI clock.
MIDI CHANNEL
By default, Polyphrase listens to midi channel 1. You can change the midi channel by
following the steps below.
1. Power on the pedal while holding the “SYNC” button and continue holding until
the sync LED starts blinking.
2. Now send a midi CC message on the desired channel. The sync LED will stop
blinking and the pedal will now listen to messages on that midi channel. This
setting will be remembered between power cycles.
MIDI ADAPTER
The MIDI input is a 1/8” stereo jack that is wired for a Type B midi adapter. If you are
unsure what type of adapter to use, you can purchase one directly from Vongon on our
website.
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POWERING
POLYPHRASE was designed to operate using your typical center negative, regulated 9
VDC power supply. The pedal is protected against reversed polarity and overvoltage
conditions. Always check your power supply for proper voltage and polarity before
connecting. There is no battery connection inside the pedal.
EXTENDED WARRANTY
Vongon will repair or replace any malfunctioning product for a period of 2 years aer
purchase date. Problems resulting from modifications or misuse may cancel this
warranty. The owner will cover all shipping expenses. This warranty applies only to the
original owner of the product. Proof of purchase might be required.
In general, the best thing to do is to contact us as soon as possible with a description of
the symptoms, even if the warranty is expired.
CONTACT
Please feel free to reach out to Ryan or Katie with any questions -
[e-mail]
CHANGE LOG
VERSION
CHANGES
1.0
Initial commit
15