Kenton Pro-4 User Manual

OPERATING INSTRUCTIONS FOR

PRO-4

MULTI-CHANNEL

MIDI TO CV CONVERTER

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CONTENTS

Introduction
The PRO-4s channels 3
Front/back panels 5
Setting up your PRO-4

MIDI connections 6
Analogue connections 6
Clock connections 7
Trimmer adjustments, tuning 8

Editing the PRO-4
Recalling and storing set-ups 9

Parameters

CV output parameters 10
Digital output parameters 12
Using the KADI port with your TR606/808 13
Auxiliary output parameters 14

LFO`s 15

Sync settings 16
System settings 17

MIDI Analyser Mode 17
Polyphonic Mode 18
MIDI System Exclusive information 19
Pin Outs for DCB/Wasp 22
Connecting a modified TB303 or SH101 (socket retro`ed) 23
Specifications 24

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INTRODUCTION

Congratulations on your purchase of the Kenton Electronics PRO-4 multi channel MIDI to CV converter,

which has been designed to give you maximum flexibility, whilst maintaining ease of use.

The converter has eight completely independent sections - called channels A, B, C, D, E, F, G, & H. Each

channel can be assigned its own MIDI channel, and controlled independently from each other.

The PRO-4 has four independent, MIDI programmable LFO`s that can modulate any of the CV outputs,

and four of the auxiliaries. Each of the CV channels has a portamento function.

There are also many other features designed to make the PRO-4 as flexible as possible to allow as much

control as possible over your analogue synthesizers.

The PRO-4 has a thorough MIDI system exclusive specification for those who wish to do data dumps or

editing from their computer sequencer or generic patch editor.

Please take some time out to read through all of this manual which should hopefully explain all you will

need to know.

THE PRO-4 CHANNELS

CHANNELS A, B, C, & D

These are for controlling analogue synths such as the SCI PRO-1, Roland SH-101, or indeed most other
synths with CV and Gate inputs.

Note, the CV output for controlling the pitch uses the Volts per octave (V/oct) pitch scaling system. This is
the most common system used in analogue synths, as used in Roland, SCI, Oberheim and Moog synths.
Synths such as Korg & Yamaha, (MS20, MS10, CS5), work on a different pitch scaling system. This is called
Hertz per volt (Hz/V). To control the pitch of these synths correctly, the optional four channel Hz/V board
will need to be fitted. This is available as a plug in card. Contact us for details.

Some synths do not have CV, Gate or Filter inputs, such as the TB303. We can fit or supply socket kits for
most monosynths that do not have inputs. Contact us for details.

CHANNEL E, the EDP Wasp port

This channel is a digital output for controlling the EDP Wasp or Gnat synth.
Note, the Wasp responds to three octaves of notes only - on a DX7 or other 61 note keyboard, this

corresponds to bottom C#, to C, three octaves above. The Wasp does not respond to pitchbend - or
indeed any other controls except sustain pedal, which will hold the current note, this is a design limitation
of the Wasp itself.

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CHANNEL F, MIDI channel filter

This is used to rechannelize or filter MIDI data.
Connect the synth to the PRO-4 MIDI out socket, and set the MIDI filter receive channel to the MIDI

channel music data you want your old synth to respond to. Only data received on that channel will be
sent out of the PRO-4 MIDI out, and any other channels will be filtered out. This data can be sent out on a
different channel if required (see rechannellizing above). An example of rechannelizing might be to
change the transmit channel of early DX7s, for instance, that can only transmit on MIDI channel 1, to
another MIDI channel, say 2. An example of filtering might be on an early MIDI synth that can only
receive in Omni mode (receive on all MIDI channels at the same time), the Jupiter 6, for example.

CHANNEL G, the DCB port

DCB (digital communications bus) is an old digital port Roland designed for linking up their poly synths,
such as the Juno 60 or some Jupiter 8s. This is a polyphonic interface. It only sends note information, but
on Jupiter 8s with DCB, it will also do program changes.

CHANNEL H, the KADI port

The KADI (Kenton Auxiliary Digital Interface) is a digital port. This can be used to play the TR606 or TR808
drum sounds over MIDI, although a small modification will have to be made to the drum machine.
It is also there for any possible future expansion. Note, special cables are needed to use the Wasp, DCB &
KADI ports. These are available direct from Kenton.

SYNC 24 & Clock Pulse

The PRO-4 has a Roland SYNC 24 clock output. Instruments having a SYNC 24 input, such as the TB303,
TR808, TR606, MC202, can be connected to the PRO-4. If the PRO-4 is receiving MIDI clock, these
instruments will play their internal patterns in time to MIDI clock.

The PRO-4 also has a clock pulse (arpeggio output). This can be used to synchronize drum machines,
analogue sequencers, and arpeggio`s to MIDI clock.

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FRONT PANEL

Access to channels A to D`s tuning trimmers are gained from the front panel.
Each channel, A to D, has LED indicators to indicate when that channel`s Gate is on.
There are two more LED status indicators;

One is marked DATA. This indicates whether the PRO-4 is receiving MIDI data.
The other is marked SYNC. This indicates whether the PRO-4 is receiving MIDI clock messages.

Four buttons; PARAMETER, VALUE, LOAD and STORE, and also a Data Entry Dial.
These are for editing the PRO-4 & are explained later in the manual.

2x20 backlit LCD, and power switch.

BACK PANEL

From left to right, there is the;
IEC power socket (power lead supplied).
MIDI In, Out, and Thru DIN type sockets.
Sync24 DIN socket.
Clock pulse minijack output.
The Wasp/DCB and KADI ports, D-type sockets.
The eight auxiliary minijack outputs.
And the four analogue channels` Trig, Gate, CV & Hz/V (if fitted) minijack outputs.

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SETTING UP YOUR PRO-4

MIDI CONNECTIONS

MIDI IN

- connect this to the MIDI Out of your MIDI synth or MIDI sequencer using standard MIDI cables.

MIDI OU T

- connect this to the MIDI In of your MIDI sequencer or old synthesizer. This is only needed if you will be
editing the PRO-4 using SYSEX or doing MIDI data dumps, or if you are using the MIDI channel filter.

MIDI THR U

- this provides a copy of the information coming into the MIDI In socket so that you can "daisy-chain"
several MIDI devices. It should be connected only to a MIDI In socket if needed.

ANALOGUE CONNECTIONS

CV A, B, C, & D (-1 volt to 5 volts)

- the control voltage output to control the pitch of most synths, such as Roland, SCI, and Moog.
Connect this output to the input marked CV, oscillator, KBD IN, VCO CV in, VCO, KEY Volt in, etc., of your
synth.

Hz/V A, B, C, & D (optional)

- these optional outputs are to control the pitch on synths such as some of the KORG and YAMAHA synths.
This output works in conjunction with the CV output.
Connect this output to the input marked CV, oscillator, KBD IN, VCO CV in, VCO, KEY Volt in, etc., of your
synth.

GATE A, B, C, & D (off=0 volts on=+15 volts)

- the gate voltage output that provides the note on/off information for synths. This is used for most synths,
such as Roland, ARP, or Oberheim.
Connect this output to the input marked Gate in, TRIG in, etc., of your synth.

S-TRIG A, B, C, & D

- this output has 7 triggering options selectable in the software.
S-Trig - this is used to control Moogs, Korgs.
The tip of the jack is the trigger signal - if your synth has the CINCH/JONES connector with two flat pins,
the narrower pin is the trigger signal and the wider one is ground.
Trigger - Can be used to trigger ARP envelopes or analogue sequencers.
Connect this output to the input marked S-Trig in, TRIG in, etc., of your synth.

AUXILIARIES 1 to 8 (-13 to +13 volts)

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- a voltage output for connecting to an auxiliary input on a synth such as filter control or VCA volume.
Connect this output to the input marked VCF in, VCF fcM, Filter, etc, on your synth to control the filter cut-

off, or the input marked VCA, Volume, loudness, etc., to control volume. You could also connect this to
inputs such as portamento, pulse width, high pass filter cut-off, etc.

Cable Connections

All minijack outputs on the PRO-4 need standard 3.5mm mono minijack plug. The connection at the synth
end of course depends on what synth you are using.

THE ARP CLOCK & SYNC 24 OUTPUTS

CLOCK PULSE - (arpeggio clock)

- this output provides a 5 volt clock pulse related to the incoming MIDI clock. The ratio of MIDI clocks to
arpeggio pulses can be adjusted - (see CLOCK PULSE DIVIDE).

A 5 volt voltage will be outputed on the first MIDI clock after a MIDI start (or continue if selected) is
received, and thereafter dependent upon the CLOCK PULSE DIVIDE ratio.

You may wish to connect this to an input marked Ext. Clock In on an analogue drum machine or
sequencer. It could also be used to gate/trigger envelopes or Sample and Hold circuits in time to MIDI
clock.

SYNC 24 - (DIN 24 sync, used on SOME ROLAND equipment)

- this output provides clock and stop/start signals.
Pin 1 - Stop = 0 volts Start = 5 volts (or continue if selected)

Pin 3 - 5 volt pulses; 24 clocks per quarter note, the same as MIDI
Pin 2 - Ground
Pins 4 & 5 are not used.

Cable Connections

MIDI leads are not suitable for connecting to the SYNC 24 socket as they have different pins connected.
Use a 5 pin DIN to 5 pin DIN audio lead available from a HI-FI shop.

Connect this output to the SYNC 24 input on a TR606/808, MC202, or TB303 to synchronize these
instruments` sequencers to MIDI clock.

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TRIMMER ADJUSTMENTS FOR CHANNELS A, B, C, & D

Tuning in your PRO-4 and your analogue synths.

INITIAL

- tunes the PRO-4 to the synth.

SCALE

- adjusts the octave scaling of the PRO-4 to match the synth. When the PRO-4 leaves the factory, this is
set to the standard 1 volt per octave, but some synths may require some adjustment of this control if the
octaves are out of tune with each other.

It may be that your synth is slightly out of tune, so it will be necessary to tune the PRO-4 to your synth;
1, Tune your synth (when playing from its own keyboard) correctly with your digital synths first. Do this by

adjusting the tuning or pitch knob on your analogue synth whilst playing middle C on both synths. (To do
this, you may need to disconnect the analogue synth from the PRO-4).

2, Now, with the PRO-4 connected to the analogue synth, play middle C on your digital synth. Both synths
should sound. With a small flat blade screw driver, tune in the PRO-4 with your analogue synth by
adjusting the INIT trimmer on the front panel.

3, When your digital and analogue synths are once again in tune, play a key two octaves up on your
digital synth. Now adjust the SCALE trimmer till both synths are in tune. The analogue synth should now
play correctly across its range from your master keyboard.

Use a small, thin and narrow, flat blade screwdriver to do this.

(range approx 2 octaves)

(range approx 20%)

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