RADICAL DELTA CEP A User manual

Owner’s Manual
DELTA CEP A

A!EU Declaration of Conformity!5"------------------------------------------------
B!COMPLIANCE!6"-----------------------------------------------------------------
C.!WARRANTY and safety instructions!7"-----------------------------------------
C.1 !Warranty service!7"--------------------------------------------------------------
C.2!Eligibility !7"-----------------------------------------------------------------------
C.3!Transferability of the guarantee !7"---------------------------------------------
C.4!Damage claims !7"---------------------------------------------------------------
C.5!SAFETY INSTRUCTIONS!7"----------------------------------------------------
1.!Introduction!9"--------------------------------------------------------------------
1.1!DELTA CEP A - a semimodular, paraphonic Synthesizer!9"------------------
1.2!Installation and first use!9"------------------------------------------------------
2.!Overview!11"-----------------------------------------------------------------------
2.1!Connection required - MIDI or CV/Gate?!13"-----------------------------------
2.1.1!MIDI - Music Instrument Digital Interface!13"-----------------------------------
2.1.2 !CV/GATE!13"-----------------------------------------------------------------------
2.2.!Audio connection and play!14"---------------------------------------------------
2.3!Troubleshooting!16"---------------------------------------------------------------
3.0!The sections of the DELTA CEP A in detail!18"----------------------------------
3.1!LFO Section!18"-------------------------------------------------------------------
3.2!Swarm Oscillator Section!20"----------------------------------------------------
3.2.1!Scale Quantizer!21"---------------------------------------------------------------
3.2.2!Paraphonic Operation!23"--------------------------------------------------------
3.3!Mixer section!24"------------------------------------------------------------------
3.4!Filter section!26"-------------------------------------------------------------------
3.5!ADSR section!28"------------------------------------------------------------------
3.6!VCA Section!30"-------------------------------------------------------------------
3.7!FX Section!31"---------------------------------------------------------------------
3.7.1 !Tape Delay!32"---------------------------------------------------------------------
3.7.2!Tempo Delay!33"-------------------------------------------------------------------
3.7.3!Chorus !33"------------------------------------------------------------------------
3.7.4!Phaser !34"------------------------------------------------------------------------
3.7.5!Flanger!34"-------------------------------------------------------------------------
3.7.6!FX-Section In- and Outputs!35"--------------------------------------------------
4.!Patches & Snapshots!35"---------------------------------------------------------
4.1.!Storing of Snapshots!35"---------------------------------------------------------
4.2!Storing Patches (sound programs)!35"------------------------------------------

4.3!Recalling Patches!36"-------------------------------------------------------------
4.5!Snapshot Morphing!37"-----------------------------------------------------------
4.5.1!Snapshot sequencing!37"--------------------------------------------------------
4.5.2!Snapshot morphing!40"-----------------------------------------------------------
4.5.3!Modulation wheel-dependent morphing!41"------------------------------------
4.5.4!Velocity-dependent morphing!41"------------------------------------------------
4.5.5!Aftertouch-dependent morphing!42"--------------------------------------------
4.5.6!CV dependent morphing!42"-----------------------------------------------------
4.6!The combination of different modulation sources!42"--------------------------
4.7!Notes on the number of snapshots.!43"-----------------------------------------
4.8!Muting of snapshots!43"----------------------------------------------------------
4.9!In the beginning there was the INIT sound!44"----------------------------------
4.10!Deleting all snapshots!45"--------------------------------------------------------
5.!Patch dump functions!45"--------------------------------------------------------
6.!Note-trigger and note priority settings!47"--------------------------------------
7.!MIDI to CV Interface!48"----------------------------------------------------------
7.1!MIDI clock synchronization!49"---------------------------------------------------
7.2![TEMPO]-button and tempo LED at MIDI-sync mode!51"---------------------
7.3![TEMPO]-button and tempo LED when running with internal clock !52"------
7.4!Clock-Output jack and Clock-Divider!53"---------------------------------------
8.!Tuning the Delta CEP A!53"-------------------------------------------------------
9.!Setting up LED brightness and color!54"----------------------------------------
10.!Auto Power-Down function (DESKTOP version only)!54"----------------------
11.!RT-311 bridge!55"-----------------------------------------------------------------
12.!Technical Information!56"---------------------------------------------------------
13!Glossary!57"-----------------------------------------------------------------------
13.1!Filter (lowpass, bandpass, highpass)!57"----------------------------------------
13.2!Interpolation!58"-------------------------------------------------------------------
13.3!MIDI!59"
13.4!Waveforms!60"---------------------------------------------------------------------
13.5!TLM Modulation (Time Linearity Modulation)!60"-------------------------------
13.6!The difference between a gate and a trigger signal!61"------------------------
14.!Preset Patches!62----------------------------------------------------------------
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DELTA CEP A Owner’s manual
Version 1.1 for firmware version 1.1. Jörg Schaaf, Radikal Technologies Deutschland
GmbH, Copyright © 2019
For Radikal Technologies the highest quality standards are ectremely important, and as
such our products are constantly evolving. Technical changes made to improve a product
may be made at any time without notice. Therefore, technical data and the appearance of
the device may differ from the information given or illustrated in this manual.
Any duplication, even in part, in any form and for any purpose, requires the written
permission of Radikal Technologies Deutschland GmbH. (c) 2019, Radikal Technologies
Deutschland GmbH"
"
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A EU Declaration of Conformity
The manufacturer /distributor:
"
Radikal Technologies GmbH!
Eduard-Schmid-Str. 27!
81543 München!
Deutschland!
hereby declares that the following product:
Product name: Music synthesizer without keyboard"
Commercial: Eurorack Semimodular Synthesizer Module"
Device name: DELTA CEP A"
Type: DELTA CEP A Eurorack & DELTA CEP A desktop"
Serialnumber: ____________"
Productnumber: RT-01"
Chargenumber: 1/2019"
"
complies with the provisions of the Low Voltage Directive 2014/35 / EU, including
amendments that were in force at the time of the declaration.
The following harmonized standards were applied:"
EN 55013: 2003"
EN 55020: 2003"
EN 61000-3-2: 2000"
EN 61000-3-3: 1995 + Correction 1998"
"
"
München, 01.03.2019
"
Herr Jurgen Korduletsch Herr Jörg Schaaf"
Geschäftsführer Leiter Entwicklung
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B COMPLIANCE
FCC INFORMATION (U.S.A)
IMPORTANT NOTICE: DO NOT MODIFY THIS UNIT! This product, when installed as
indicated in the instructions contained in this manual, meets FCC requirements.
Modifications not expressly approved by Radikal Technologies GmbH may void your
authority, granted by the FCC, to use this product. IMPORTANT: When connecting this
product to accessories and/or another product use only high quality shielded cables. Cable/
s supplied with this product MUST be used. Follow all installation instructions. Failure to
follow instructions could void your FCC authorization to use this product in the USA.
NOTE: This product has been tested and found to comply with the requirements listed in
FCC Regulations, Part 15 for Class „B“ digital devices. Compliance with these requirements
provides a reasonable level of assurance that your use of this product in residential
environment will not result in harmful interference with other electronic devices. This
equipment generates/uses radio frequencies and, if not installed and used according to the
instructions found in the user manual, may cause interference harmful to the operation of
other electronic devices, Compliance with FCC regulations does not guarantee that
interference will not occur in all installations. If this product is found to be the source of
interference, which can be determined by turning the unit „OFF“ and „ON“, please try to
eliminate the problem by using one of the following measures:
Relocate either this product or the device that is being affected by the interference. Utilize
power outlets that are on branch circuits (circuit-breaker or fuse) install AC line filter/s. In
the case of radio or TV interference, relocate/reorient the antenna.
If the antenna lead-in is 300 ohm ribbon lead, change the lead-in to coaxial-type cable. If
these corrective measures do not produce satisfactory results, please contact the local
retailer authorized to distribute this type of product. The statements above apply ONLY to
products distributed in the USA.
FCC INFORMATION (CANADA)
DELTA CEP A Version 1.0 FCC Information (CANADA)
The digital section of this apparatus does not exceed the „Class B“ limits for radio noise
emissions from digital apparatus set out in the radio interference regulation of the Canadian
Department of Communications. Le present appareil numerique n’emet pas debruit
radioelectriques depassant les limites applicables aux appareils numerique de la „Class B“
prescrites dans la reglement sur le brouillageradioelectrique edicte par le Ministre Des
Communication du Canada.This only applies to products distributed in Canada. Cecine
s’applique qu’aux produits distribues dans Canada."
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C. WARRANTY and safety instructions
C.1 Warranty service
Radikal Technologies provides a warranty for 12 months following purchase for electronic
and mechanical components of the product, subject to the conditions described herein. If
defects occur within this warranty period that have not occurred due to improper handling of
the device, these will be remedied by replacement or repair of the device. The general
terms and conditions of Radikal Technologies apply.
C.2 Eligibility
Radikal Technologies Deutschland GmbH reserves the right to make the free
implementation of the repair or the replacement of the device dependent on the warranty. In
order for the warranty period to be determined, warranty returns must always be
accompanied by the proof of purchase as a copy. The final decision on the warranty applies
exclusively to Radikal Technologies Deutschland GmbH. If a legitimate warranty claim
occurs, the product will be repaired or replaced within 30 days of receipt by Radikal
Technologies. If mechanical damage and / or external interference is detected, any
warranty entitlement invalidated. Products without warranty claim will be repaired for a fee.
The costs for packaging and delivery will be invoiced separately and charged in advance.
For legitimate warranty claims, the product will be sent postage paid within Germany.
Outside of Germany, the delivery is at the expense of the customer.
C.3 Transferability of the guarantee
The warranty is only for the original first purchaser and is not transferable. Apart from
Radikal Technologies Deutschland GmbH, no third party (dealer, etc.) is entitled to assure
or execute warranty services. Guarantees beyond those mentioned above will not be
granted.
C.4 Damage claims
Claims for damages of any kind, especially due to consequential damages, are excluded.
The liability of Radikal Technologies Deutschland GmbH is limited in all cases to the value
of the product. All services and deliveries are made exclusively on the basis of the General
Terms and Conditions of Radikal Technologies Deutschland GmbH.
C.5 SAFETY INSTRUCTIONS
ATTENTION: Please keep the Eurorack case closed to prevent electric shock. There are
NO functions or adjustment options for the user inside the Eurorack case. In case of
malfunctions, contact only qualified service technicians.
Never expose the device to rain or moisture to prevent electrical shock and short circuits. If
liquid has entered the unit, immediately unplug the power cord or AC adapter from the wall
outlet and contact a technician. You should never turn on a wet or damp device as it may
cause major damage and may result in a risk of electric shock.
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DETAILED SAFETY INSTRUCTIONS
Please read the safety and operating instructions of the device carefully before using. Keep
the safety and operating instructions of the device accessible at all times.
This device is designed to be operated exclusively in a closed Eurorack housing. Never use
it outside such an enclosure, as this may cause malfunction and damage that may void its
warranty.
Observe the installation instructions in this manual so that you do not make a mistake when
installing the module in the housing."
"
If you are uncertain at any point when installing and connecting the module, do not hesitate
to contact us. We are happy to help you with questions about installation.
Never operate the device near water (bathtub, sink, swimming pool, etc.) When installing
the device make sure that it is not exposed to heat sources (heating, amplifier power
amplifiers, etc.).
The Eurorack housing with the DELTA CEP A module should be installed on firm,
sufficiently stable ground. The Eurorack housing may only be operated with suitable mains
voltage sources or power supply units specified by the manufacturer. For safety reasons,
please read the instructions in the manual that the housing manufacturer supplied with the
device before putting it into operation."
"
The power cord or power supply cable should be routed so that it does not pose a
stumbling hazard. Always use only flawless and undamaged power cords or power
supplies. Turn off the case and remove the power cord before moving or transporting the
device.
Before cleaning you should disconnect the Eurorack housing from the power supply."
"
Turn off the case and remove the power cord or power adapter cable if the device is not
going to be used for a long time.
Only clean the module with a dry cloth or cloth slightly moistened with water.. NEVER use
cleaning agents as this could damage the paint or screen printing. Make sure that no
objects or liquids enter the front panel.
In the event of sudden temperature changes, condensation may form inside the module.
Please make sure that the Eurorack housing with the module has a few hours to evaporate
the condensed water, before you connect it to the mains voltage after a temperature
change.
The device should be inspected by a qualified service technician if: "
- Objects or fluids have entered the housing. "
- The device was exposed to rain or moisture. "
- The device has fallen to the ground and/or has mechanical damage. "
- The device does not work in the usual or described way and incorrect operation can be
excluded.#
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1. Introduction
Congratulations on your purchase of the DELTA CEP A Synthesizer. Whether you use it in
its basic configuration in a modular system or as an expressive solo, bass or sequencer
synthesizer - we hope you enjoy the instrument.
!
1.1 DELTA CEP A - a semimodular, paraphonic Synthesizer
You probably know what these two adjectives mean. For many of you, they may have even
been the reason to include the DELTA CEP A in your setup. The following paragraphs are
for those who bought the DELTA CEP A because of the sound, without worrying about the
meaning of these two features."
"
Semimodular?
A modular synthesizer is an electronic sound and noise box made up of individual modules
for sound research, which have no pre-wiring apart from their common power supply.
Sound and noise generating modules, such as oscillators or noise sources can be freely
connected to sound modifying modules such as filters. A third category of modules - the
modulators - such as low-frequency oscillators (LFOs) and envelopes, provide automated
control of sound parameters. For beginners, so much freedom can quickly become
confusing. That’s why semimodular systems such as the DELTA CEP A have pre-wiring,
which greatly simplifies entry into the world of modular systems and, ultimately, electronic
sound generation. Once you gain experience with the pre-wired system, you can break or
add connections to enjoy all the freedom of a modular system."
"
Paraphonic?"
Paraphonic synthesizers can be played polyphonically, because their oscillators allow for
independent pitching according to chords. Although all of its oscillators share the same
filter, VCA, and envelopes, polyphonic oscillator control allows for multiple voices to be
played simultaneously, which is ideal for pad sounds. The DELTA CEP A sounds particularly
good in paraphonic mode, because it consists of two oscillators per voice, which provide a
nice beating effect when two oscillators are detuned against each other.
!
1.2 Installation and first use
Before we go into the detailed description of the DELTA CEP A features, we first need to
install the unit into a Eurorack cabinet. DELTA CEP A Desktop customers can of course skip
this chapter. Before you start to install the module, you should disconnect the mains plug of
the Eurorack cabinet."
Next, calculate the power requirements of the installed modules in the cabinet plus the new
DELTA CEP A synthesizer (12V 140mA, -12V 80mA). To calculate the current consumption,
add the current values of all installed modules. The overall power consumption should be
below the cabinets maximum current for both voltages +12V and - 12V. In the following
example table you see a typical calculation:
Power Calculation
+12 V
-12 V
5 V
DELTA CEP A
140 mA
80 mA
0
MODUL XY
180 mA
40 mA
0
Module XX
220 mA
180
0
SUM
540 mA
300 mA
0
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So in the example above the cabinet power must provide 540 mA at +12V and 300 mA at
-12V. If the cabinet is not capable of providing the necessary current, you should not install
the DELTA CEP A. "
The Eurorack Standard has a 16 wire bus with pin headers. In the picture below you can
see a typical boxed 16 pin header but unfortunately it is not used by all manufacturers and
the Doepfer Technical Documents even suggests that only unboxed pin headers be used.
In our opinion most modules have been destroyed so far, because no protection against
misplaced sockets exists on most modules and bus systems.
The good thing about such a shrouded header is that you can connect the socket of ribbon
cable only in one direction with the plug. In fact, boxes have a "nose" that has to be
inserted into the slot seen above - and of course this only works if it is correctly aligned. But
even more important - the sensitive pins of the pin header are protected with the help of the
box against mechanical stress. On "crooked" follows quickly "off", if you have to straight out
the pins again. Now take the supplied ribbon cable and plug it into the 16 pin base of the
DELTA CEP A board. The boxed 16-pin header is easy to identify and is equipped with the
"POWER" label for the sake of simplicity."
Now take a look at the power supply circuit board of the Eurorack cabinet and the supplied
power cable of the DELTA CEP A. The power cable has 16 wires and a color marking on
the first wire (usually blue or red). On the bus board in a Eurorack cabinet, the first two
contacts carry -12V. Please make sure that the first wire with the color marking is always
connected to the -12 volt side of the pin headers. Also make sure that the cable is not
pushed to the right, left, up or down. Unfortunately, the Doepfer bus system has no reverse
polarity protection so please be extra careful at this step#
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Once you have connected the cable, you can put the DELTA CEP A in the correct position
and screw it on with the enclosed screws and washers. Please use the plastic washers to
prevent damaging the varnish."
If everything is set up properly, you can turn on the power. At the same time a few of the
Delta LEDs should light up and flash. If this is not the case, stop the power immediately and
look for the error. But as a rule, the DELTA CEP A will now work and we can concentrate
on the operation."
2. Overview
Before taking a closer look at the capabilities of the synthesizer, let's take a look at the
interface of the DELTA CEP A Synthesizer from left to right."
Interpolator"
Sitting on the left side are the eight + six LEDs, six buttons, and the large knob. This section
has several functions. You can recall and save presets, take snapshots, morph through
them, set the system tempo, as well as adjust various device settings. The eight LEDs not
only display occupied snapshots, but above all serve to visualize parameter settings.
MIDI2CV"
This is a well-equipped MIDI to CV interface that allows you to convert MIDI signals into
control voltages for additional modules. To control the DELTA CEP A via MIDI, you do not
need to use any of the interface's outputs - the modulation sources and targets in the
DELTA CEP A sections are already prewired.
LFO 1!
The LFO has 5 waveforms, MIDI and clock synchronization, and an invertible modulation
depth control."
SWARM OSC!
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The Swarm oscillator provides up to 8 oscillators. Paraphonic play modes (allowing 4
voices to be played simultaneously), pitch quantization, and easy tuning access are the
highlights of the Swarm oscillator."
!
Mixer!
This section mixes the outputs from the oscillator and the noise source or an external signal
for the filter. The signal of the oscillator can be overdriven.
VCF"
The filter section of the DELTA CEP A offers three different filters - a digital 12 dB
multimode filter, an analog 12dB multimode filterm, and a digital 24 db lowpass filter.
ADSR"
The ADSR envelope section provides crisp sound curves. As a highlight, this section offers
a voltage control for the attack and decay time.
VCA"
The VCA can be controlled by either the ADSR envelope or the gate signal. The VCA
section also provides external inputs for the following FX processor.
FX"
The right side of the front panel contains the effect section with delay, chorus, flanging and
phasing effects."
"
Some words about labelling!
If you check the labelling on the DELTA CEP A front panel you will notice different color
schemes: white characters on blue background, white characters on black, etc.
Labelling on the DELTA CEP A frontpanel.
Output jacks are marked with black characters on a blue background.
Input jacks are marked with white characters on a black background.
One input jack in the LFO section has a special function when the morph mode
is active. We marked that with black charachters on a white background.
The framed white characters are only used for one button and two knobs. The
button [PARAPHONIC] has the framed labelling ‘QUANTIZER’. By holding the
[QUANTIZER] button down, you get access to the two alternative features for
the knobs SCALE ROOT and SCALE SEL. Please check Chapter 3.2.1 for
more details.
[MANUAL] has an open frame marking. Open frame labellings are indicating
that you get access to further functionality by holding the button down until all
LEDs 1-8 light up.
White characters on blue background are marking shift-functions. The DELTA
CEP A has alternative functions for buttons and knobs. Hold the [SHIFT] button
to access them.
White characters on a black background are marking the basic function of a
button or a knob.

TLM

SHIFT
MANUAL
1

SCALE ROOT


1V/OCT


PITCH
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2.1 Connection required - MIDI or CV/Gate?
You can elicit a sound from the DELTA CEP A without connecting a keyboard, sequencer,
calculator or anything else. Simply press the [GATE]-button in the ADSR Envelope section.
But that's not fun. There are generally two ways to provide the DELTA CEP A with external
information that causes it to produce sounds and effects - the MIDI interface and a CV
voltage paired with so-called gate or trigger signals.
!
2.1.1 MIDI - Music Instrument Digital Interface
The DELTA CEP A has a MIDI input on the front panel. If you just want to play it over a MIDI
keyboard, connect the MIDI output of the keyboard to the MIDI input of the DELTA CEP A
and play it on the keys of the keyboard. If you see the GATE LED light up while playing,
you've done everything right. If the keyboard is set to a different MIDI channel, hold down
the DELTA CEP A [LEARN] key and press a note. Now the control should work. "
"
Of course, if you have the desktop version of the DELTA CEP A, you can use the MIDI input
on the back of the device. Not only does this provide cosmetic benefits - the MIDI data is
routed to the MIDI THRU output when using the rear MIDI input."
2.1.2 CV/GATE
CV is an abbreviation for Control Voltage. For Eurorack modules, the following voltages
were set as standard:
"
A keyboard with a CV output that complies with the 1V / Octave standard can be plugged
into the 1V / Oct input of the oscillator section. On the very popular Arturia Keyboard
'KEYSTEP' this output is labeled 'Pitch'.
In contrast to the CV voltages listed above, the gate signal is usually a so-called ramp
voltage with a fixed voltage value. Without gate signal we measure 0 Volt and with gate
signal a certain, not changing voltage. The Eurorack system has a gate voltage of + 5V. To
increase compatibility and reduce the susceptibility to errors, most GATE-controlled inputs
can handle significantly lower or higher voltages. The DELTA CEP A will process gate
signals between 2 and 10 volts without any problems. Thus, the envelope can also be
triggered by a rectangular LFO, which can only output a maximum of +2.5 volts.
A CV / GATE keyboard will normally output the gate signal as long as you hold down the
key. Pressing the button thus triggers the gate voltage and releasing the button switches
the gate voltage back to 0 Volt. The pitch CV voltage, on the other hand, is usually
outputted until another key with a correspondingly different CV voltage is pressed. This is
important so that the pitch does not drop when you release the key. Sounds often have a
certain release time, during which the pitch should of course remain stable. Use caution
Control- and Signalvoltages in the world of Eurorack.
Pitch Control
The standard is set to 1 volt per octave. In other words, when the
voltage is increased by one volt, the pitch of an oscillator doubles -
which is one octave.
LFO Output range
The LFO modulation voltages typically range between -2.5 and +2.5
volts (5VPP).
ADSR output range
Usually between 0 and 8 volts.
Audio Signals
Audio signals, which can also be used for modulation, usually have a
voltage swing of 10 Vpp (between -5 and +5 volts)
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when working with a very old CV keyboard with a sample and hold circuit that drops in
voltage after a few minutes. For long tones, you should activate the pitch quantizer of the
Delta for safety. Reliably corrects the voltage drops of old keyboards.
Connect the GATE output of the keyboard to the GATE input in the ADSR section.
2.2. Audio connection and play
Now you have made a MIDI or CV / GATE connection and want to play the DELTA CEP A
safe first extensively. There are basically two options:
"
"
Exploring the DELTA CEP A.
1
You play in manual mode and adjust the sound with the controls, buttons and cables
until you like them. In doing so, you will get to know the device very well and, with
the descriptions following in Chapter 3, you will get an accurate picture of your new
synthesizer.
2
You are listening to some of the preset sounds that are in memory. Granted. That
sounds tempting. About 70% of the storable synthesizers are not programmed by
the user. (Fake News ??) But you won’t be successful in finding own sound by
stepping thru presets. It is very unlikely that your personal sound is already in there,
because sounds are rarely played alone, but have to fit in the context of other
sounds. Because of this, you will inevitably have to learn to lend a hand if your
sound is important to you.
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DETUNE MOD DEPTH
MODWHEEL
CHORDS
FM-DEPTH
SCALE ROOT
QUANTIZER
SCALE SEL.
TLM
PATC H BANK
SHIFT
GLIDE
LEARN
MIDI IN
MANUAL
TEMPO
SNAP
MUTE
MIDI2CV SWARM OSC
1V/OCTMOD
FM
TIME
FEEDBACK
DRY/WET
FX-SELECT
MOD-DEPTH
MOD-RATE
FX-INPUT GAIN
MOD LP BP HP EXT IN
WAVE EG/GATE
GATE
DENSITY
PITCH
OSC
1
2
3
4
5
6
7
8
EXT/NOISE
WAVE
CUTOFF MOD
EG DEPTH
KB-SCALE
VELOCITY
VCA ATTACK
VCA RELEASE
HOLD/MORPH TRIG
VCF ADSR
1V/OCTRESOCUTOFF DECAYATTACKGATE
RESONANCE
CUTOFF
DECAY
ATTACK
RELEASE
SUSTAIN
ADSR
RADIKAL TECHNOLOGIES
MIXER
FX IN R
FX IN LMOD
MOD-DEPTH
VELOCITY
VOLUME
VCA FX
PARAPHONIC
DEPTH
LFO 1
SYNC
DEPTHSPEED
SPEED
INTERPOLATOR
1/8
1/4
1/2
1/16
1/32
1
8
4
2
6
4
37
28
9
10
0
1
5
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9
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0
1
5
6
4
37
28
9
10
0
1
5
DIG12dB DIG24dB ANA12dB
PATC H
MORPH
+
-
PITCH 1V/OCT
0V 1V 2V
GATE

Before you start, you need to connect the DELTA CEP A to your mixer or powered speakers
(Nerds have thrown the manual into the corner by now because they connected their Delta
ages ago)."
"
The DELTA CEP A Desktop version has audio outputs with 6.3 mm jack outputs on the back
- so you do not need an adapter or adapter module with large and small jacks to connect
the Desktop DELTA CEP A to the mixer, soundcard or active speaker system."
"
The Eurorack version looks different. However, we assume that you have already
connected other modules to the outside world and therefore have all the necessary
adapters and cables to connect the DELTA CEP A. Otherwise, we recommend a small
multiples module such as the Doepfer A-181, with which you can connect the small jack
plugs with large jack cables. Alternatively, there are ready-made adapter cables with a
small and a large jack. That would be the cheapest solution by far. Make sure these cables
are MONO.
What we do NOT recommend are adapters that have a 3.5mm jack in the front and into
which you can insert a large jack cable directly behind. These types of adapters provide a
high mechanical load for the 3.5mm sockets of all modules."
"
At the bottom right of the front panel in the FX section you will find the exits to the outside
world in the Eurorack version."
"
Did you connect the DELTA CEP A to powered speakers or a mixer? Here again all
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DETUNE MOD DEPTH
MODWHEEL
CHORDS
FM-DEPTH
SCALE ROOT
QUANTIZER
SCALE SEL.
TLM
PATC H BAN K
SHIFT
GLIDE
LEARN
MIDI IN
MANUAL
TEMPO
SNAP
MUTE
MIDI2CV SWARM OSC
1V/OCTMOD
FM
TIME
FEEDBACK
DRY/WET
FX-SELECT
MOD-DEPTH
MOD-RATE
FX-INPUT GAIN
MOD LP BP HP EXT IN
WAVE EG/GATE
GATE
DENSITY
PITCH
OSC
1
2
3
4
5
6
7
8
EXT/NOISE
WAVE
CUTOFF MOD
EG DEPTH
KB-SCALE
VELOCITY
VCA ATTACK
VCA RELEASE
HOLD/MORPH TRIG
VCF ADSR
1V/OCTRESOCUTOFF DECAYATTACKGATE
RESONANCE
CUTOFF
DECAY
ATTAC K
RELEASE
SUSTAIN
ADSR
RADIKAL TECHNOLOGIES
MIXER
FX IN R
FX IN LMOD
MOD-DEPTH
VELOCITY
VOLUME
VCA FX
PARAPHONIC
DEPTH
LFO 1
SYNC
DEPTHSPEED
SPEED
INTERPOLATOR
1/8
1/4
1/2
1/16
1/32
1
8
4
2
6
4
37
28
9
10
0
1
5
6
4
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10
0
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6
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1
56
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6
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0
1
56
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10
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1
5
6
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9
10
0
1
5
6
4
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9
10
0
1
5
6
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9
10
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1
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1
5
DIG12dB DIG24dB ANA12dB
PATC H
MORPH
+
-
PITCH 1V/OCT
0V 1V 2V
GATEMIDI
OUT

connections in the overview. You only need to wire either the MIDI or the CV / GATE
connection:"
"
Let’s begin the party!
2.3 Troubleshooting
Most users, like me, don’t give a shit about manuals. You only get it when something does
not work the way you thought it should or just you ask a question in a forum. Here are the
most important stumbling blocks in the operation:"
"
"
1.) Exploring in Manual Mode.
Button
Knob/Button
Description
- - -
SHIFT/
MANUAL
Immediately after switching on, the DELTA CEP A is actually
already set to MANUAL mode. In manual mode, the LED to
the right of the [SHIFT / MANUAL]-button lights up in green. If
it does not light green, simply press this button!
ALL
ALL
Every controller and every button counts. No matter if with or
without manual. Get to know the DELTA CEP A. Play, get
familiar with the device. If something does not work anymore,
troubleshooting in chapter 2.3 might help. The instructions are
divided into the individual sections. So if you stumble over a
parameter name in a section that you can not initially recall,
you will find the necessary explanations in the 3.00 ffsection.
2.) Exploring in Patch Select Mode.
Button
Knob/Button
Description
- - -
PATCH
Immediately after switching on, the DELTA CEP A is in
MANUAL mode. Press the [PATCH] button to enter the
PATCH-SELECT mode and recall the preset sounds.
- - -
MORPH &
MUTE
Below the [PATCH] button, the two [MORPH] and [MUTE]
buttons are labelled with a '+' and a '-'. With these two
buttons you can call up the sound programs one after the
other in PATCH mode. There are simple single tones
underneath that can get by with just one snapshot and there
are a few more complex examples that automatically call
sequential 8 snapshots. If you are not familiar with terms like
"snapshots" or "sequential", you understand why variant 1 of
the DELTA CEP A exploration. These terms are in fact clarified
in the manual.
- - -
SHIFT
With the [SHIFT] -key you exit the patch-select mode again in
the direction of manual mode.
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"
Troubleshooting
Knobs and buttons do not respond.
Make sure you have selected Manual mode. Just
touch the [SHIFT / MANUAL] button. The LED to
the right of this button should now light green. The
same state is reached when you turn the device off
and on again, because the DELTA CEP A basically
always starts in manual mode.
BP and HP button in the filter section do not
respond.
You have selected the 24dB lowpass filter. Since
this filter provides only one low-pass, the other two
buttons are not active. Use [SHIFT] & [DIG12dB] or
[SHIFT] & [ANA12dB] to select one of the
multimode filters. These provide as usual the switch
between low pass, bandpass and high pass. If you
activate low-pass and high-pass at the same time
and turn back the resonance, you can also create
great notch filter effects.
You play a tone, but the sound generation
remains silent, even though the VCA and the
VCO level control are adjusted.
Take a look at the VCA. Is the VCA EG/GATE LED
lit? If not, the setting probably prevent the VCA from
letting the signal through. Press the [EG / GATE] key
in the VCA section once or twice to assign the
envelope or gate signal to the VCA. In both cases,
the LED lights up.
I hold the [SHIFT / MANUAL] button and
suddenly find the unit in a completely different
mode.
The [SHIFT] key allows you to call alternate
parameters of knobs and buttons. The parameters
that can be accessed using the [SHIFT] key are
printed on the front panel on blue labels. If you hold
down the [SHIFT] key without turning a knob or
pressing a button, you may load the Utility menu.
Just look at the LED chain on the left, if you hold
down the [SHIFT] key. You will see that all blue
LEDs 1-8 are turned on one after the other. When
you release the button, the LED to the right of the
[SHIFT] button will not turn green because you have
landed in the Utility menu. No panic. Touch the
[SHIFT] key to exit this mode.
When I switch from a preset to manual mode to
edit parameters, the current sound suddenly
sounds quite different.
Each preset consists of up to eight snapshots,
which may sound completely different. To edit a
sound, you must first select the desired snapshot.
In manual mode, hold down the [SHIFT] key and
load a snapshot by selecting it with the big knob
and then releasing the shift key. Now you can edit
this snapshot in the value fetch mode.
While in patch mode, the potentiometers and
buttons on the surface do nothing.
That's because each preset consists of up to 8
snapshots. On which snapshot should the pots
affect when you start to turn the knobs in patch
select mode?
I use the MORPH mode and would now like to
change parameters during an LFO morph
animation.
Use the control voltage inputs for real-time sound
changes during a snapshot animation. Please note
that some of the control voltage inputs are
equipped with the option to set the modulation
depth. If the modulation depths are turned to 0 in
the snapshots used, the control voltage inputs will
of course do nothing.
von 17 63

3.0 The sections of the DELTA CEP A in detail
3.1 LFO Section
The LFO (LOW FREQUENCY OSCILLATOR) section of a synthesizer is the most
important and widely used modulation source. An LFO generates periodic modulation
voltages. The LFO of the DELTA CEP A can be tuned far into the audio range and allows
both MIDI and external clock synchronization.
Knobs and buttons of the LFO-Section.
Button
Knob/Button
Description
- - -
DEPTH
The DEPTH knob adjusts the voltage swing of the modulation
voltage and thus the modulation strength. In the middle
position, the strength is 0. To the left and right, the strength of
the modulation is increased while the modulation voltage in
the left value range is additionally inverted.
- - -
SPEED
The speed control adjusts the speed of the LFO.
SHIFT
SPEED
If you want the LFO to sync to the current tempo, hold down
the [SHIFT] key while adjusting the Speed knob. As long as
the LFO does not receive external synchronization, the internal
tempo clock is the deciding factor for the speed. In this case,
you can change the speed by tapping quarter notes on the
[TEMPO] button. If you hold down the [SHIFT] key, you can
only select speeds that correspond to the printed note values
according to the current tempo.
Knobs and buttons of the LFO-Section.
Button
von 18 63
PATC H BAN K
WAVE
DEPTH
LFO 1
SYNC
DEPTHSPEED
SPEED
1/8
1/4
1/2
1/16
1/32
1
8
4
2

- - -
WAVE
You can use the [WAVE] button to select the waveform of the
LFO.
- - -
WAVE
In 'Patch Select' mode, you can use the [WAVE] button to
access the 5 memory banks. The LEDs of the LFO Wave
Selection will light up according the bank number 1-5. See
chapter 4. "Programs and Snapshots".
Knobs and buttons of the LFO-Section.
Knob/Button
Description
Knobs and buttons of the LFO-Section.
Button
In- and output jacks of the LFO-Section.
Jack
Input/Output
Description
SPEED
Input
An applied control voltage controls the speed of the LFO.
SYNC
Input
A clock signal on this input allows the LFO to get
synchronized to an external clock source. In the case of an
external clock input, the Speed knob works as a clock divider
for the LFO speed as soon you hold down the [SHIFT] key
while adjusting.
DEPTH
Input
With a control voltage applied to this input, you can control
the voltage swing of the LFO wave. Higher voltages increase
the modulation depth.
OUT
Output
The periodic modulation voltage can be taken from this
output. Connect the output of the LFO to a modulation inputs
of other sections or external modules to learn more about the
impact of the LFO on modulation targets.
von 19 63

3.2 Swarm Oscillator Section
The Oscillator section is the heart of every subtractive synthesizer. The oscillator generates
waveforms in the audible frequency range. Up to eight oscillators can be heard
simultaneously. The oscillator section of the DELTA CEP A provides smooth waveform
selection (see Chapter 12. Glossary), TLM modulation for pulse width modulation on
rectangle waveforms and sound changes on other waveforms, FM modulation, waveform
morphing, and more. Highlights include the integrated tone scale quantizer, the chord
memory and the paraphonic playability."
"
Knobs and buttons of the Oscillator section.
Button
Knob/Button
Description
- - -
WAVE
With the WAVE control, you can continuously crossfade
between different oscillator waveforms. The basic waveforms
are sine, triangle, sawtooth and square.
SHIFT
TLM
Use the [SHIFT] key to reach the TLM control with the WAVE
knob. TLM behaves like a pulse width parameter for square
waveforms, but also alters other waveforms by shifting the
midpoint of the waveform and correspondingly compressing
or stretching the front or back half of the vibration.
- - -
PITCH
With the pitch control you can adjust the pitch of the
oscillators over a wide range.
SHIFT
PITCH
Hold down the [SHIFT] key as you turn the pitch knob to get
an exact tuned pitch and switch octaves.
Knobs and buttons of the Oscillator section.
Button
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DETUNE MOD DEPTH
MODWHEEL
CHORDS
FM-DEPTH
SCALE ROOT
QUANTIZER
TLM
SWARM OSC
1V/OCTMOD
FM
DENSITY
PITCHWAVE
PARAPHONIC
6
4
37
28
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10
0
1
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9
10
0
1
5