Workshop: SOMA Pulsar-23 with the guitar

SOMA Pulsar-23 with guitarThe SOMA Pulsar-23 can also process external signals and so I asked myself whether and, if so, how you can combine a guitar with the semi-modular drum synthesizer.

SOMA Pulsar-23 with the guitar: The setup

The drum machine has numerous inputs that are intended for audio and CV signals. The internal delays, reverb effects and other modulations can sound very exciting with the guitar. A compact setup consisting of an electric guitar and a drum synthesizer can then have the potential to explore completely new sound paths and become creative.

In this workshop I am using the SOMA Pulsar-23 in the new screw version. The crocodile clips hold very well on the recessed screws and several clips can be attached to one screw. The Pulsar-23 is amazingly versatile, even if you start without a patch cable, you can create a lot of different sounds. The kick can be shaped from a crisp and powerful bass drum, a softer kick or a subtle click using just the pots for attack and decay. The pitch can be adjusted quite well with pitch and tune. The same applies to the synthesizer or percussion, snare and hi-hat module. And when you connect the most diverse modules together, the fun really begins.

To me it is exciting that the Pulsar-23 can be triggered in four ways and that you can combine them. It works via external MIDI, internal sequencer, live playing or with the internal clock and its subdivisions. This way you can create really crazy rhythms.

The guitar and the SOMA Pulsar-23

I connect my guitar to one of the 6.3 mm jack sockets on the back. To get a strong guitar signal, I use an amp modeler in front of the Pulsar-23, which increases the volume and delivers the amp sound. The guitar signal is then connected to the ¼ Jacks module, at the bottom left of the Pulsar-23. First, I simply patch a rhythm and then connect the guitar signal to the delay section. In the sound files and the video, I will therefore first focus on the three delay versions. Later, of course, I will test the reverbs and a tremolo effect.

Pulsar-23

In order to be able to hear both the guitar signal and the effects, I split the guitar signal and connected the direct signal to the mix-in input of the Pulsar-23. Another signal goes directly to the delay or reverb.

The delays of the Pulsar-23

If you set the effects toggle switch to the left, a bandpass filter delay is available with BPF. As the name suggests, this delay has a bandpass filter that can be used to shape the sound of the delay.

The DBL is a double delay that offers two virtual tape heads. The delay time of the second tape head can be tuned by using the pot. It is perfect for rhythmic repeats.

The CH delay is a delay with a pitch shifting effect. The delay time is set with the time potentiometer, filter and pitch effects with the tune potentiometer and the number of repeats with the feedback potentiometer. The delay out potentiometer controls the volume of the effect.

Modulation is of course also possible. But for us guitarists it is done in a quite different way. On the one hand, the intensity of the modulation can be set with the clock mod potentiometer. The modulation itself is carried out via a control voltage signal from a corresponding module. The LFO can of course be used for this in the classic way. But it gets even crazier when the modulation is controlled via different sample and hold CVs or even via the touch CV plate. With this CV contact, the intensity of the modulation can be controlled via the amount of the finger surface that touches the contact. If this CV module is connected to the delay time and the feedback, it gets really exciting.

It’s great that each of the potentiometers mentioned can be controlled with a CV. This means there are almost no limits to the modulation.

In the first sound file of the video, I selected the BPF delay and controlled the feedback via a CV touch plate. This way, accents can be set and the delay can be driven into oscillation.

After that, I use an LFO to generate the modulation that modulates the delay time. Since I have connected the LFO to another CV plate, I can switch from a light chorus effect to a vibrato with finger contact. At the same time, I play with the feedback part.

I set the pitch delay to a higher octave. Together with the more aggressive industrial drums, the whole setup in the third sound example sounds really crazy.

Since the Pulsar-23 also offers stereo effects if you patch it accordingly, I naturally tested the double delay in stereo. The two virtual tape heads in the stereo panorama deliver a wide range of sounds and are perfect for ambient sounds.

The reverb effects

If you switch the FX switch to reverb, you can select three reverb algorithms. Here you can choose between two reverb variants and a reverb with pitch shifter. In this case, too, the effect can be adjusted with time, tune and feedback as well as the reverb out.
You can of course also use both effects at the same time by connecting the corresponding signal to the delay and reverb input.

In the sound file, I have chosen a strong reverb effect that sounds really great. Together with the corresponding drums, the Pulsar-23 gives you a great sound that is really fun.

Pulsar-23

The second reverb is a little more subtle and the reverb with pitch effect can, like the pitch delay as well, create different intervals. Lower octaves are also possible.

The LFO, attenuator and CVs

The modulation via LFO is done via a square or sine wave. Using another potentiometer, these waves can be bent into rising or falling sawtooth waves. Both can be set in frequency using a potentiometer and a triple toggle switch that selects between low, mid and hi. Even the modulation can be modulated by connecting the LFO module to other modules. No delay pedal offers such options of modulation.

For the more daring, the sample and hold module is an interesting alternative, which offers a more random modulation. The intensity is attenuated via an attenuator using a potentiometer, as it is common in the modular world. The corresponding attenuator is simply patched in.

Stereo effects of the semi-modular drum synthesizer

The Pulsar-23 has stereo delay or stereo reverb if you patch it accordingly. To do this, the 10 volt output must be connected to the Mad input of the effects section. The two outputs of delay and reverb can then be tapped and connected to two pins of the 6.3 mm jack sockets. The effect signal can then be mixed into the signal as desired using an external mixer.

Tremolo effects of the Pulsar-23

To create a tremolo effect with the SOMA Pulsar-23, I connected the guitar signal to the input of the VCA, i.e. the voltage-controlled amplifier, and this output to the mix-in input. The CV signal for the VCA comes from the LFO. To adapt the modulation speed to the song tempo, I synchronized the LFO with the clock. And a tremolo has been created easily.

Here, too, the LFO can of course be modulated using touch CV to create faster tremolo effects at specific points. If you want, you can of course also route the tremolo signal to the delay or reverb or connect the VCA to the sample and hold module for a few random rhythms.

Conclusion

I would like to end this workshop with these sounds, which sound excellent to my ears and are really inspiring. There are of course still numerous patch variations and ideas, because the SOMA Pulsar-23 is really more versatile than you might initially think. For example, the effects could be modulated by the individual triggers or envelopes of the kick, snare or hi-hat modules. Or you can modulate these modules using the guitar signal. Trying things out and experimenting is expressly encouraged here and I am curious to hear what other ideas and tips one or two readers have. So have fun with the SOMA Pulsar-23 and your guitar!