paradis Polybass User manual

User Manual for Polybass-P + Shield
(version for any instrument)
Why do we make such an effort?
Bass is fundamental
working as a sound engineer, playing in bands, studying the history of instrument making
and analog electronics, the feeling became stronger every year that bass is much more
important than it seems. it’s unfair that the bass player is in the background, but it also ts
to his fundamental task of stability and coordination for all other musicians.
Harmonies are built from harmonics of the fundamental tone. on primitive instruments like
the fanfare its only possible to play those notes, and hearing the bass tone, we feel why
all other notes belong together and why the notes that are not directly in the scale create
an interesting tension...
more so, I feel that the vibrations resonate in our bodies and a concert or dance night is
not just a social and cultural event but also a therapy... short:
IF I COME HOME FROM A SHOW AND DID NOT FEEL SOME LOW BASS, I AM NOT SATISIFIED !!
How to create the bass in a small ensemble
unfortunately not in every combo there is space for a bass player. there are probably more
duos and trios of voice, guitar and percussion or harmonica and clarinet and so on where
one of those instruments takes the musical task of the bass player, yet on an instrument
which does not have the size to create a real low bass.
BUT:
we are lucky that engineers of the last decades created portable woofers that ll a big
room with solid and profound bass! so one of the band can play a bass pedal and its done.
how clumsy and synthetic! we have a better solution: we divide the lowest notes of the
guitar so that they turn into bass notes! the guitar plays as usual, maybe a bit more aware
of its function, and the bass comes out for free, low and alive, discrete and present, but
not calling attention or pretending to be another instrument: everyone can see who plays
those notes, no one cares why they sound so low, but they feel satised
The physics of intervals
since the scales are made of harmonics which are multiples of the bass note, the higher
climb in the scale, the more notes we get, the closer the intervals are. and also: the high-
er the frequency, the shorter the wave, the quicker we identify notes. so an interval that
sounds good on the guitar can sound wobbly one octave lower!
V 2.2 April 2020

adjust the eect volume
for D-string
here you can connect
a LED that blinks when
the battery is weak
solder battery wires
select the volume of
each string by adding
gain to the weaker
ones (default is all
closed)
set VCA volume of
PBass eect
mixing connectors for
jumpers and potenti-
ometers
gain of the 7th string or
2nd pickup (magnetic,
body piezo, mic...)
all inputs and the mix
outputs are on this con-
nector called X1
X2 to 13pin out
insert connector for
external mono eect
like wooDi-m
What is different about Polybass
there have been many approaches to create bass, but not for a clean single bass line! ba-
sically, one octave generator which switches to the lowest played string would be enough.
but we found that sudden switching between strings call attention. so we made an octave
generator for each string, tune it to the string and then select the lowest note and fade
the previous. then a steep lter takes its color, so instead of sounding like an instrument
which is not on stage, it just vibrates totally synchronous to the guitar string.
The complete high class preamp system
Polybass is not only the low bass but a complete 7-channel low noise low power preamp
and mixing system, designed to give you the maximum possible options for conguring and
mixing any kind of pickups in any guitar. the 7th channel can amplify a magnetic pickup,
a body piezo or even a microphone and on the Shield there is another preamp with notch
lter in case you need 7 strings or some more pick up option.
Support for configuration and wiring
we understand the diculties of musicians and lutiers to deal with electronics, schematics
and solder iron. Paradis Guitars went through phases of using too much electronics and
learned to reduce to standard parts, long life, low power, low noise...
the right amount of electronics simplies the conguration outside the instrument and
makes it sound the same wherever its connected: clean, noise free and large!
wiring can be soldered or crimped or at cable. the headers are not soldered yet so they
can be added on either side and angled or not. we ask the questions you need to nd the
right system and then provide all necessary parts and information (which may not yet be
complete here)
in the 90ies we explained to the world what livelooping was good for, now you can partic-
ipate in this evolution...

About this manual
Polybass adds a low octave to each string separately, thats why it works so accurately.
Godin/RMC produced many instruments with the necessary hexaphonic pick-up, thats why
we made the board t perfectly into guitars with the RMC Polydrive system. if you own such
an instrument, the installation is very simple, explained in a separate Polybass-R manual.
This manual starts with a quick install of a pre-mounted kit and explains the basics to the
user. then it becomes increasingly more sophisticated, rather for luthiers and engineers,
showing all the options to build the Polybass-P into any guitar and adapt the features
acording to the needs of the user.
originally all was wired directly to the board. then we created the Polybass Shield which
makes all simpler and adds tone control and many other features.
its dicult to make this manual complete. please ask whatever you do not understand and
we help and invent and add to the manual... so make sure you grab the latest version!
Credits
I came up with all this, but I would not reach anywhere without good friends!
Philipp Scheidegger is the very experienced electronic engineer who simulated the details,
reduced power consumption, draw the schema, made the layout, and nally thought me
how to use the layout software so I am free to complete and modify what he did!
Tom Maier of 24dB.de had the great idea to replace a RMC pcb’s to make this plug and play.
Rein, Taivo and Vahur of spicetone.com organized the manufacturing and testing of the
boards
Heinz “Rüebli” Fässler of Rueblirock.ch is the great inventor and mechanics who nds the
right solutions and materials, prints and lasers...
Vasilis Kotareles of media5.ch created the site and explained me how to complete it, test-
ed, took pictures and always brings some good mood and great music!
Randolph Arriola of embryosongs.com helped in great discussions to understand the busi-
ness situation, my texts, this manual... and always feeds with his love for what we do...
Adrian Schackmann similarely tested, thought, recorded, explained, encouraged...
Ursetta Mutzner of muurmeli.ch was always patient to listen to my stories and keeps our
place cozy and tasty, created the Messe booth, went to the post oce in-numerous times
and reminded of what I forget...
Rolf Spuler could not participate in this version physically any more, but his incredible spirit
is always present and brings quality and precision...

Contents
Why do we make such an effort? 1
Bass is fundamental 1
How to create the bass in a small ensemble 1
The physics of intervals 1
What is different about Polybass 2
The complete high class preamp system 2
Support for configuration and wiring 2
About this manual 3
Credits 3
Quick installation Polybass without Shield 5
All on the Input Connector 5
External controls wiring 6
Parallel mixing 6
Master volume control 6
Pickup balance 6
Quick installation Polybass + Shield 7
Input connection 7
Output connection 7
Control connection 8
Understanding and Adjustments 9
Priority 9
Battery low warning 9
Power consumption 9
Li battery 9
Adjustable volume for each string 10
D4 string Bass volume 10
The little trimmer on the component side 10
Filter jumper 10
Roland GuitarSynth and compatible 11
Resonances in your instrument 11
Into which instruments can we install? 12
Acoustic guitars 12
Les Paul family 12
Strat family 12
Yamaha Silent 12
Archtop 13
Paradis Eden 14
Paradis Avalon 14
What can we continue to use? 15
What pick-ups can be used? 15
What controls do you need? 15
What kind of controls are available? 15
how to mount the controls in the instrument 16
What output connectors you need? 16
Polybass Shield board connectors 17
Input connector 17
Output connector 17
Volume control connector 17
Tone control connector 18
Roland GK controls connector 18
WooDi Switch connector 18
Connectors Shield - Polybass 18
Polybass board connectors 19
Input connections 19
Output connector 20
Insert connectors 20
VCA, LED and Priority connectors 20
Insert connector for wooDi-M etc 21
jumper for Insert connector 21
Mixing Options 22
Parallel (no Master): 22
Master and Aux: 22
Master and Parallel: 22
Master and Balance: 22
Passive Magnetic Pickup 22
OutputPCB board 23
Cable service 23
Split Polybass effect out 24
Connector options for split outputs 24
Remove the PBass from the Main? 24
How to switch back to mono 25
Implementation of the Split PBass out 25
Volume control for the split PBass 26
VCA and GK control 26
CV control off the Polybass effect 26
three volume steps for PBass 26
Roland GK control 26
Piezo input gain 27
increase gain for Ghost pickups 27
Dimensions 28
Polybass board (Shield is the same) 28
OutputPCB 28
FingerWheel PCB 28
Potentiometer TT P09X 29
Potentiometer TT P160 29
Thumb wheel control 30
Slider Alpha RA3044F 30

Quick installation Polybass without Shield
the most simple way to use Polybass is by connecting the hex pickup at the input and the
1/4 jack at the output and a battery. this can all be done on one header connector:
All on the Input Connector
you can solder each wire to the spot indicated,
but we rather recommend to use a header con-
nector and possibly a at cable to which you
then can solder wires.
the header can be soldered on either side, pref-
erably straight on the component side or an-
gled on the trimmer side.
we do not use the VCA (necessary for RMC/
Godin), and set it to maximum with a jumper or
solder bridge as indicated.
we can send you a pre-wired kit like this if you inform the kind of controls and connectors
and cable length

External controls wiring
in case you install the Polybass with the Shield, this page is not correct since the controls
are connected to the Shield. but the kind of wiring is the same:
insert the wires you need into the conector housing and solder them to the potentiometer.
or use a at cable.
in chapter “Options of Mixing” you can nd the schema and more versions, here we show
the most frequent solutions
Parallel mixing
Master volume control
instead of the Clean volume as shown in the last paragraph, you can install a master volume
on X1. pin14 is the output from the sum amp and on pin7 it returns to the output stage.
so in the above example you would need to simply join pint7 and pin14, but you can also
add a volume potentiometer, a lter or whatever eect you like.
Pickup balance
instead of separate volume controls you may want a balance. this is especially interesting
if you have a magnetic pickup or microphone on channel 7 so the balance control will give
you on one end only the bridge piezo and on the other only the magnetic pickup.

Quick installation Polybass + Shield
the Shield makes installation easier and brings new features like:
• tone control: Bass / Mid / Treb
• another Aux input with a feedback reducing notch lter for a microphone or body piezo
• serves as hum shield instead of metal vbox or metal foil
as you see on the picture above, we deliver tested kits with the controls and functions you
choose and the cable length you need.
Input connection
connect Graphtec Ghost pickups
or
solder the pickups in one of the 3
ways shown below.
Output connection
for a solid body or generally shielded guitar the
output wire does not need to be shielded so its
easier to use the output connector.
or
on the left the solder pads also oer all signals.
usually we deliver with those wires soldered.

Control connection
depending on the kind of controls you use, they can be connected with one or two 6 or
12 pin ribbon cables or with crimped wires. one connector is for 2-3 volume controls, the
other for 2-3 tone controls.
for acoustic guitars, the thumb wheel potentiometers in the sound hole are interesting be-
cause there is no need to drill into the guitar
in this case we had no Aux and no Mid so two small connectors were sucient:

Understanding and Adjustments
Priority
probably the most unique part of the Polybass is the priority function:
only the lowest played string is audible and switches the higher ones o. its useful enough
that we make it active all the time.
the priority idea comes from the physical fact that we easily hear small intervals in the
higher octaves but perceive the same interval as rumbling or wobbly when its in the lowest
octave. that’s why a bass player usually only plays one note at the time. so if you play a
4th on the lowest strings of the guitar, it sounds ne, but if we then add the lower octaves
for both notes, its too much. thats why we need the priority function to only add the lower
of the two notes as the bass line.
as far as we know, no other equipment on the market does this. thank you for respecting
our patent of 1992!
in the classic Polysubbass unit, there was a switch
to turn priority o. few people have used this, but
if you like to hear the octave on all 3 bass strings
at once, you can install a switch to Prio1 (A-string)
and Prio2 (D-String). for version < PB-P-0045 un-
solder the two zero-ohm resistors on the compo-
nent side, on the newer boards you have to scratch
the tracks.
Battery low warning
the rst sign of the battery becoming exhausted (~5V) is when strong attacks mainly on
the D string cause a delay of the subbass sound. when dropping further, the delay also hap-
pens on lower strings and softer attacks. we think this is a rather helpful indication since
the musician will notice but hardly the public.
for those who want a visual warning before this, you can connect a LED that ashes when
the battery drops to about 7V. (see chapter LED installation)
Power consumption
the Polybass consumes 4mA and wooMe or Shield another 3mA. so a 9V battery with
700mAh theoretically serves for 100h.
Li battery
We recommend rechargeable batteries to protect the environment. in case of professional
musicians more so, because many exchange the battery before its empty, just to make
sure that it does not interrupt the performance. so charge before an event! the NiXx bat-
teries have less capacity and loose their charge by themselves and then the acid comes out
and eats the contacts and more. Li (and eneloop) batteries maintain charge much better
and the Li have higher capacity. since a Li cell is about 3,6V, two cells produce 7,2V which
is still enough for the Polybass. we are also trying to convince the industry to produce 9V
batteries with 3 Li cells. the resulting 11V would make most pedals work better...

Adjustable volume for each string
the RMC pickup is amazingly balanced, other pickups need correction. it can be helpful to
adapt the string volumes to playing style, to string characteristics, to musical intentions…
from outside with a little screwdriver, boosting the weak strings…
D4 string Bass volume
by default, the Polybass eect on the D4 string is similar to the E6 and A5 string. but some
musicians like to have no eect on the D4 string and others prefer it to be lower so there
is a transition between the strings with eect and the ones without.
try out your setting on the single little trimmer on top of the board!
The little trimmer on the component side
as long as you do not use the VCA you can forget about this tiny trimmer. it is set once to
adjust the silent point. (see chapter VCA and GK control)
if you use the VCA to control the Polybass eect volume, and its not totally gone when
you close the pot, adjust the trimmer.
Filter jumper
the original RMC system has a treble enhancement on the input and a compensating treble
cut on the output. that’s why there is a compensation lter on the Polybass, switchable
with a jumper which is not set in the -P version. but maybe you can use it anyway? as it is, it
cuts treble and creates a warm sound for nylon strings. we can also change its components
for some other lter desire.
we usually do not install ltering into the instrument because we think its better to lter in
a mixing desk or dedicated lter unit. at, the Paradis guitars sound great.

Resonances in your instrument
every guitar has some resonances in the neck and the body that “eat” the energy of cer-
tain notes, so they fade away quicker than the others. this eect is known for hundreds of
years and cello makers invented tricks to minimize the problem but the more alive the wood
construction is, the stronger resonances it has. usually the worst is around G...A.
those irregularities are better audible with the Polybass, but not related to it. so sorry, we
cannot x this, but you can improve a lot by holding the neck (or sometimes the bridge)
rmly when you play that note.
it may be possible to reduce the resonances of your instrument by adding a cover over the
sound hole or stien the top for example by adding a bridge between top and bottom.
Roland GuitarSynth and compatible
the Polybass is capable to drive polyphonic (hexaphonic) eects and sythesizers compati-
ble with the Roland GK 13pin DIN system. you can install the GK Synth volume and the Up/
Dn buttons however you want them and connect them to X1 or the specic connector on
the Shield.
note that due to the compatibility to RMC there is
a jumper that allows to control the PBass from the
same Synth volume, but this hardly makes sense out-
side of the RMC environment. so usually you will want
to set this PBass control to max with this jumper:
Similarely, there is a jumper to disable the GK vol-
ume control in case the RMC GK slider is supposed to
only control the Polybass but not the synth. so if you
want to control the Synth Vol, this has to be set:
for better understanding and more options read chapter VCA and GK control

Into which instruments can we install?
virtually any instrument can be improved with a Polybass!
you will love the new possibilities:
the piezo sound on electric guitar brings clarity and an aspect of acoustic. the Polybass
with Piezo pickups oers a much better hidden GK option than the original Roland kit. if
you do not like the 13pin DIN (which really has issues) consider using a better conector in
the guitar.
Acoustic guitars
the sound is improved with the hexaphonic pickup because by amplifying each string,
the pickups are no loads for each other. and you can very simply add a microphone into
the guitar to add more of the acoustic sound. the Polybass oers this additional input.
you can choose polyphonic piezos from several manufacturers and place a Shield+Polybass
anywhere but probably accessible from the sound whole. the 2-6 controls also can be
choosen and placed acording to taste.
Les Paul family
Graphtech and LRBaggs supply the Tune-o-
matic bridge which is trivial to replace. the
wires need a little hole and can go from the
bridge pickup to the potentiometer depart-
ment where the Polybass ts with some carv-
ing but with the original cover, so no change
is visible from outside.
Strat family
several manufacturers oer direct re-
placement bridges. you probably do
not want the tremolo with the piezos
because they pick the moving noise.
so routing the space for the springs
5mm larger towards the controls
makes the Polybass t under the orig-
inal back cover and opens a channel
for the cables. the tone pot can turn
into the PBass volume and nothing is
visible from outside.
Yamaha Silent
we oer a special version of the Shield
which replaces the SLG100...130
board with all potentiometers and
connectors so no soldering is required
and nothing is visible from outside. it
not only brings hex quality and PBass
but increases battery live about 5
times and reduces noise drastically.

Archtop
Graphtech and LRBaggs sup-
ply the Tune-o-matic bridge
which is trivial to replace.
some archtop guitars have a cov-
er on the back or you can create
one if you do not mind, so its rath-
er easy to build the board into the
hollow body, possibly screwing it
to the back cover - which can be
the Paradis plexi we made for the
RMC version, we sell it separately.
if you do not want to drill into the
instrument, you can create a big
enough pick-guard and screw or
glue the Shield to it.

Paradis Eden
this guitar has been built for FireWire, so the space is too big for the Polybass. but it serves
as an example of a Shield built especially for the Paradis Pickup and the existing space. we
can do the same for your guitar, or rather for your guitar model since you probably would
nd the development to expensive for a single instrument.
consider that this is nice in a pretty solid guitar but on a thin top you probably would not
want the weight and resonances of the electronics, rather cable it to the bottom
Paradis Avalon
this is not quite working yet, but you see where the Polybass got her neat roundings from

What can we continue to use?
its nice to continue with whatever is installed on a guitar already. or at least the holes, so
we do not need to drill new ones. its sometimes an extra eort to nd out how to include
or modify best, but we are experienced and willing to help:
• if you have a pickup installed, is it hexaphonic? if so we probably can use it
• if you have a 9V battery installed, we use it. is the wire long enough? we can extend or
replace them, possibly with the clip
• do you want to reuse the controls? is there one you do not need so it can serve for the
PBass volume? are they correct value (10k...50k)?
• if you replace the controls, can we at least reuse the buttons? depends on the kind of
axis
• do you want to mix a body pickup or microphone to the hexaphonic main pickup? we can
connect to the Aux preamp and just need another volume or balance control
• do you want to continue with the preamp module (bass-treble ou EQ or tuner...) in-
stalled? lets see how we can connect the Polybass board to its input
What pick-ups can be used?
all the Polybass asks for is that the strings are picked up separately. we tested it with the
following piezo pickups:
• Paradis pickup need a special bridge that lets you adjust pitch and hight
• RMC works out of the box
• Graphtec Ghost just needs more sensitivity: open trimmers to half
those pickups should work but we did not test yet:
• LR Bags (maybe some level adjustment like the Ghost)
• Cicfy
• Roland GK (little bass when installed very close to bridge)
What controls do you need?
those controls you can connect directly to the Polybass or the Shield:
• Volume: either general volume or main pickup only
• Volume of the sub-octave eect, we call it PBass Vol
• Aux Volume: the 7th preamp or some externally amplied mic
• GK Synth Volume and up/down and Synth as dened by Roland. consider to use some
external MIDI control or a pedal instead.
for decades we were convinced that a well made piezo guitar does not need any lters
to sound well on at speakers. and that any tone changes are better made at the mixing
desk or with eect pedals than in the instrument. but we provide what clients want, so the
Shield oers
• Bass
• Mid
• Treble
What kind of controls are available?
in the shop we oer two sizes of conductive plastic potentiometers or 35mm sliders or
15mm thumbwheel.

this is a Rolf Spuler construction with the sliders he bought big boxes of:
What output connectors you need?
• 1/4” standard guitar connector: ordinary output of the preamplied mix. for many, this
is enough and its easy to install and solder or connect to the Polybass or the Shield
• 13pin DIN (Roland compatible): allows to output the strings separately plus a mixed
signal and the power supply (yes, you can get rid of the batteries, also with a simple
supply)
• additional 1/4” guitar connector either for the magnetic pickup (usually passive like a
electric guitar or amplied with Aux channel7) (see chapter Mixing Options)
• additional output of the split polybass signal to be amplied on a bass amplier, sub-
woofer or PA. can be a separate 1/4” connector or the ring of the main 1/4” or the
13pin (see chapter Split Polybass eect out)
we provide a board with 2 1/4” and a 13pin connector which connects to the Polybass
through a at cable. (see chapter OutputPCB Board)
technically the potentiometers are clearly superior to small sliders and thumbwheels be-
cause they are conductive plastic (live a lot longer and feel smoother than carbon or cer-
met) and the shaft is solid.
how to mount the controls in the instrument
in a solid body, you want potentiometers. but threads are usually only 5 or 6mm long so
you may need to look for a special guitar pot or work into the wood.
for acoustic guitars, potentiometers are less liked because they need a hole and stand out,
so you may opt for a sound hole thumb wheel solution. we call it FingerWheel.
it makes sense to create a control board.
here is a our new kind of thumb wheel ar-
rangement for the sound hole. it con-
nects with two at cables to the Polybass
Shield: one for 2-3 volumes and the other
for 2-3 tones. you can also wire it direct-
ly to the Polybass. we can populate less
thumb wheels or create a dierent format.
there are bigger thumbwheel potentiometers
but usually they are not easy to nd in small quantities:
http://www.taiwanalpha.com.tw/products/4
http://www.shokaifareast.com/Products/Pots/Thumbwheel/
thumbwheel.htm
http://www.piher-nacesa.com/pdf/23-T18v03.pdf
or make one from a better potentiometer as we did for
the archtop guitar you see on a previous page:

Polybass Shield board connectors
Input connector
this connector is made to receive the Ghost standard pickup connector: 2pin 2mm pitch
as you see on the picture above, the sequence is from left to right and ground is the lower
pin, the row closer to the PCB
the pin numbering is from top right, so if you use a at cable you get:
1 E6 2 GND
3 A5 4 GND
5 D4 6 GND
7 G3 8 GND
9 B2 10 GND
11 E1 12 GND
Output connector
this one goes to the output 1/4” jack and the battery
note that the battery - is not equal ground (GND)! GND is a mid voltage generated on the
Polybass board. the power switch needs to short the BatSwitch signal with GND.
1 Mix 2 PBass
3 BatSwitch 4 GND
5 Battery + 6 Battery -
Volume control connector
this connector serves for 3 potentiometers. the pinout is selected so that you can also
connect only a 6pin female in case you need only the standard 2 potentiometers. and its
made so that if you invert this 6pin, it still works, only the potentiometers are swapped.
note that the standard tone potentiometer is 25k or 50k Log (=Audio Tapper)
1 Vol piezo send 2 GND
3 Vol piezo return 4 Vol PBass return
5 GND 6 Vol PBass send

7 Vol Aux send 8 not used
9 Vol Aux return 10 GND
11 GND 12 not used
Tone control connector
just like the volume connector, this one serves for 3 potentiometers and they have the
same pinout. the last not used pinouts receive a jumper which is needed if the potentiom-
eters are not connected or only the treble is connected.
again, if you only use Bass and Treble, a 6pin female is enough and you can swap the po-
tentiometers by reversing this 6pin connector
note that the standard tone potentiometer is 100k Lin
1 Treble top 2 Bass bottom
3 Treble mid 4 Bass mid
5 Treble bottom 6 Bass top
7 Middle top 8 not used
9 Middle mid 10 Jumper disable
11 Middle bottom 12 Jumper disable
Roland GK controls connector
this is a 6 pin connector that receives the GK standard controls: a linear 100k potentiom-
eter and two momentary switches. it can also control the PBass vol (see chapter VCA and
GK control)
1 GK Vol top 2 Switch UP
3 GK Vol mid 4 GND
5 GND 6 Switch DN
WooDi Switch connector
the Polybass Shield contains the wooDi attack smoothing circuit - which may be populated
or not. if not, this connector is not either.
its layouted as a 6 pin connector like the others, but only 3 pins are used any maybe only
those 3 pins are populated
Rolf Spuler did not think that it makes sense to switch o this circuit, so this switch is
neither in the wooDi box nor in the Paradis guitars which all had this circuit on a removable
module
I heard from some wooDi users that in some situation they prefer the authentic hard attack
without the wooDi, so I leave it up to the user to switch it with a jumper or to connect a
switch. so if you connect pin 1-3 its ON and 3-5 is OFF
1 wooDi Out
3 to Tone cirquit
5 wooDi In
Connectors Shield - Polybass
1-4 connectors between the two boards exchange inputs, outputs and power. they are
described in the next chapter

Polybass board connectors
for details, get the connection schema on the site.
those are the connectors available on the board:
Input connections
X1 originally was the 14pin 0.1” header input connector.
we expanded it to serve as a general connector between Shield and Polybass. we can pop-
ulate it with as many pins as needed.
you can either connect a at cable or an input board or solder single wires.
pin 1-6 strings E1...E6
pin 7 mix out, can go to a volume pot or lter stage or directly return to pin14
pin 8 0-5V DC input for VCA or GK Volume
pin 9 mid Gnd
pin10/11 GK UP/DN keys
pin12 V+
pin13 V-
pin14 return to output, usually connected to pin7
pin15 input 7th string or body piezo or magn PU
pin16 output Pbass for mixing
after SN -P0040:
pin15 output 7th string or body piezo or magn PU
pin16 output Pbass for mixing
pin17 input 7th string or body piezo or magn PU
pin18 return 1 for mixing
pin19 return 2 for mixing
pin20 battery switch, can be the ring of the output jack, needs to short with GND
pin21 battery -
pin22 battery +
X11: power LED and pri-
ority switch
solder battery wires
X14: VCA control (usu-
ally only used with RMC
board)
mixing connectors for
jumpers and potenti-
ometers
X1: all inputs and an in-
sert so that ltering can
happen on a input board
X2:all outs, 13pin DIN
X13: insert connector
for external mono ef-
fect like wooDi-m
X12: output selector.
usually a jumper pin5-6
brings the mix
X15/16: potentiome-
ter and mixing

Output connector
X2 is the 14/16pin 0.1” header that carries all the outputs:
pin 1-6 strings E1...E6
pin 7 mix out
pin 8 0-5V DC input for VCA or GK Volume
pin 9 mid Gnd
pin10/11 GK UP/DN keys
pin12 V+
pin13 V-
pin14 battery switch, can be the ring of the output jack, needs to short with GND
pin15 output Aux 7th ch body piezo or magn PU
pin16 output PBass
Insert connectors
X13 is a 2mm header insert into the stringMix path and contains supply for eect modules:
pin1 V+ pin2 V-
pin4/6 Ground (<R-0169 or P-0050: V-)
pin5 Send pin3 Return
X15 is a 2mm header to insert volume controls or switch with jumpers:
pin1 return to mixer pin2 send String7/Aux
pin3 return to mixer pin4 send PBass
pin5 V- (pot ground) pin6 send 6stringMix (repeated from X16)
X16 is a 2mm header with the Mix volume control / switch and GK control
pin1 return to mixer pin2 send 6stringMix
pin3 Mute GKSynth pin4 ground -> jumper sets Synth vol to silent
pin5 Vol GK send pin6 Vol GK ret -> remove jumper to not control Synth
VCA, LED and Priority connectors
those two connectors are next to each other like one 12pin for several small tasks:
X11 is a 2mm header with Priority and LED
pin1 Prio A On if V- pin2 V- (both pins are connected)
pin3 Prio D On if V- pin4 V- (both pins are connected)
pin5 positive voltage to LED pin6 to LED blinking cirquit
X14 is a 2mm header with GK control and Filter (see chapter VCA and GK control)
pin1 VCA to max pin2 VCA to min
pin3 VCA input pin4 buered GK pot
pin5 RMC lter On if V- pin6 V- (see chapter Filter)
X17 is a Battery connector, polarity is written on PCB
example for Graphtec Ghost pickup connection
(obviously nicer with a Polybass Shield board)