All posts by Jorg Schaaf

SYNTHESESIA – Radikal Technologies Live Stream

OK – earlier than I expected I will go online with an open end video stream on sunday from 3:30 ET (21:30 CET). You can ask questions about the modules and the Delta CEP A and I will produce some tones with the DELTS CEP A, the Swarm Oscillator RT-311, the EFFEXX module RT-1701 and the RT-451 Dual Filter module.
You will get the chance to win a RT-451 dual filter module. The details on that give away will be presented during the show.
Here is the link to the stream:
The live stream is presented by the event!

New DELTA CEP A workshop video spotted on youtube

Trade fairs are cancelled. Workshops are postponed. In times of the pandemic, product videos are a serious alternative. I had a video series on the DELTA CEP A in mind for a long time. The first part provides an overview, while the following parts deal intensively with the individual sections of the synthesizer. My personal highlight in this pilot episode is the use of the stereo tape delay of the FX section as a looping device for a spontaneous 5 minute improvisation. This version of the video is in German. An English version will surely follow if I receive demands for it. Anyway – the audio demos will not change at all in an english language version.

Small addendum to the production of the Delta CEP A video. In some audio examples, the audio encoder of the video output in Final Cut Pro was unsuitable. I had to filter waveforms and lower the level. But I still couldn’t get a few of the digital artifacts under control in a manageable amount of time. At least after a certain number of attempts, I was tired of filtering the waveforms more and more. It was poking in the dark. I knew the problems came from overtones that I couldn’t hear anymore, but my young listeners might. The Delta CEP A simply has extremely clear waveforms with overtones up to the Nyquist frequency. For this reason, here is a link to the uncompressed wave file with the audio samples that the encoder did not want to process properly. The unfiltered Swarm oscillator signals were particularly affected. In the analyzer of the Logic Pro X EQ you can very nicely observe how far the overtones in the DELTA CEP A range for rectangular, pulse and sawtooth waveforms.


Messen fallen aus. Auf Workshops wird verzichtet. In Zeiten der Pandemie sind Produkt-Videos eine ernstzunehmende Alternative. Eine Video-Reihe zum DELTA CEP A schwebte mir schon lang vor. Der erste Teil dient einer Übersicht, während sich die folgenden Teile intensiv mit den einzelnen Sektionen des Synthesizers auseinandersetzen. Mein persönliches Highlight ist die Nutzung des Stereo-Tape-Delays der FX-Sektion als Looping Device für eine spontane 5 minütige Improvisation. Diese Version des Videos ist in deutscher Sprache gehalten. Eine englische Version wird sicherlich folgen, wenn dieses Format Zuspruch findet.

Kleiner Nachtrag zur Produktion des Delta CEP A Videos. Bei manchen Audio-Beispielen zeigte sich der Audio-Encoder der Video-Ausgabe in Final Cut Pro ungeeignet. Ich musste Wellenformen filtern und den Pegel senken. Aber ein paar der digitalen Artefakte bekam ich trotzdem in überschaubarer Zeit nicht in den Griff. Zumindest hatte ich ab einer gewissen Anzahl von Versuchen keine Lust mehr, die Wellenformen mehr und mehr zu filtern. Es war ein Stochern im Ungewissen. Ich wusste, die Probleme kommen von Obertönen, die ich nicht zu hören vermag, meine jungen Zuhörer aber vielleicht schon. Der Delta CEP A hat einfach extrem klare Wellenformen mit Obertönen bis zur Nyquist Frequenz. Aus diesem Grund hier ein Link zu der nicht komprimierten Wave-Datei mit den Hörbeispielen, die der Encoder nicht vernünftig verarbeiten wollte. Betroffen waren vor allem die ungefilterten Swarm-Oszillator Schwingungen. Im Analyzer des Logic Pro X EQs kann man sehr schön beobachten, wie weit die Obertöne beim DELTA CEP A bei Rechteck, Puls- und Sägezahn-Schwingungsformen reichen.


New workshop Video: Radikal Technologies – Delta CEP A

We recently did a modular workshop at SchneidersLaden in Berlin. Workshops at SchneidersLaden are taking place always on Saturdays. They always start with a little modular improvisation. We are very happy that the staff at SchneidersLaden produced a great video of the entire workshop. So if you missed it you can watch it now. You will learn a lot about the Delta CEP A and in the second chapter about the Radikal Modules as well.

New workshop Video: Radikal Technologies – Delta CEP A

Radikal Technologies Workshop @ SchneidersLaden

Donnerstag, 20.02.2020 19:30

Jörg Schaaf aka Radikal Technologies will be in Berlin to talk about (and show) his latest synthesizer designs like the Delta Cep A. He is responsible for some modern classic synth designs from Germany – like the Spectralis and Accelerator. In the past years he mainly developed eurorack modules like the RT-311 Swarm Oscillator, RT-451 Dual Filter, RT-1701 Effexx or the semi-modular synthesizer Delta Cep A. His complex designs always bring a lot of functionality to the table and they can sound amazing.

See and hear for yourself during the workshop at SchneidersLaden.

Start: 7:30pm @SchneidersLaden

Participation is free / No registration required

Delta CEP A missing presets download

Unfortunately we shipped 6 units to different dealers with the new OS 1.5 but without the preset data. Below you’ll find two soundfiles with the missing preset data. One of them overwrites the USER PRESETS and the other one overwrites the ROM Presets. A big sorry to customers, who received a unit without our soundset.

The installation of the soundsets is quite simple:
1.) Connect the audio player output to the external input in the MIXER section of the DELTA CEP A which is just between the oscillator and the filter section. It is not necessary to setup the ext. signal level as the unit detects the input data independent from the set gain.
2.) Set the DELTA CEP A into PATCH SELECT mode by hitting PATCH if not already done.
3.) Play the complete file to the Delta CEP A. The LEDs left from the big knob will show the progress. It will count the snapshot memories 40 times for 40 presets with green LED lights for USER memories and yellow for ROM presets. If the level is too high the LEDs turn red. In that case just restart from the beginning with less volume.
4.) When the file has been received completely, the unit will show the pink LED lights of the PATCH SELECT mode again.

WARNING: The file with the User presets overwrites all your own user presets. But you can backup them. You’ll find all informations about that in the owners manual.

Delta CEP A Version 1.5 released

We are pleased to announce that our DELTA CEP A and DELTA CEP A Desktop products have received an extensive update. This firmware update is available to all customers and our dealers free of charge. Devices that we have delivered since 09.09.2019 have already been equipped with this new firmware.

The following features are additions by the new version:

  • the [SHIFT]-key can now be locked in, additional parameters can also be reached without holding the [SHIFT]-key.
  • In addition to the previous effects, there is now a reverb that can be used simultaneously with the other effects.
  • The LFO can now be routed to a lot of destinations without patch cords. 
  • The ADSR can now be routed to a lot of destinations without patch cords.
  • Each modulation target has an independent modulation strength setting.
  • The sound programs of the DELTA CEP A can now be switched over via MIDI.
  • The LFO can now be synchronized directly to a square wave signal.
  • The volume and  saturation intensity of the oscillator signal can now be modulated by a control voltage.

Download the new version now!
Firmware download:
Delta CEP A Version 1.5

Manual english:
Version 1.5 Info PDF english

Handbuch deutsch:
Version 1.5 Info PDF deutsch