TONE SCIENCE

Created by Ian Boddy

 

Ian Boddy has been composing and performing electronic and ambient music since the late 1970’s, becoming one of the best known and loved musicians in these genres. He has also worked extensively in sound design having produced several well known and critically acclaimed sample libraries as well as composing many library music albums. Ian also owns and runs DiN Records, which has well over 100 releases by electronic and ambient artists from across the world. The more recent sub-label, Tone Science, showcases musicians working within the fascinating world of modular synthesis.

Ian has many years of experience with modular synth systems and Eurorack, so we are delighted to be collaborating on a series of modules that allow the easy creation of some of  the complex patches that he uses in his music. Ian comes up with the ideas and we herd the electrons to make them real!

 

 

The inspiration for the Triple cross came from a complex patch that Ian had created on his vintage Serge modular, which required three separate cross fader modules and a sea of patch cables, but now all of this functionality and more has been compressed into a single 14HP wide Eurorack module. This allows everything from functioning as a three regular VCAs, through to using voltage controlled cross panning to create an evolving mix of four different source signals into a stereo output.

 

TRIPLE CROSS - IN DEPTH

The Triple Cross is very versatile, yet relatively simple to understand and use. However, as they say "knowledge is power”, so do spend a little time reading about how to configure the channels in the four different modes, and how to combine all three channels together to create a super-powerful Four to Two to One cross fader.

The Triple cross is available with either a Black (Dark Edition) or Silver front panel

 

Each of the three channels can be configured in four different ways, and all three can be used simultaneously. They do not all have to be in the same mode, so we could for example use channel 1 as a cross fader, channel 2 as a Panner for completely different signals, and channel 3 as a Linear VCA, again for different signals..

The three channels can function in four different modes, as shown below:

 

Mode 1 - Linear VCA

 

Mode One is the simplest to understand, as the channel functions as a regular VCA. We only use one input and one output for this.

We can use this configuration without a CV input, and in this case the FADE control acts as an attenuator that determines the output signal level, from 0 to 100%.

When we patch a control voltage to a CV IN the CV INPUT pot controls the level of the output and it becomes a Voltage Controlled Amplifier. In this case the FADE control acts as an Offset control. As the CV level pot is an attenuverter we can also use negative going CV voltages to open the VCA.

If we still patch a signal input to IN A, but then use OUT R instead of OUT L, then the mode of operation is reversed, i.e. the levels will now go from 100% down to zero as the FADE control is rotated clockwise ,or as an increasing CV voltage is applied. This is useful as it becomes a Voltage Contolled Attenuator rather than a Voltage Contolled Amplifier.

The input signal can be either Audio or CV voltages, it is DC coupled so can be used for both purposes.

We can also patch an audio signal to the CV input, and in this case we can obtain some interesting ring modulation and cross modulation type sounds.

 

Mode 2 - Cross Fader

 

In mode 2 the channel operates as a two in, one out cross fader. Here we can patch different signals to IN A and IN B, then mix between them.

We can also use Mode 2 without a CV input, and in this case the FADE control increases the mix of IN A signal from 0 to 100%, and the mix of IN B signal from 100% down to 0% as it is rotated clockwise. At the half way position the output will be an equal, 50:50 mix of IN A and IN B.

When we patch a control voltage to CV IN then the CV LEVEL controls the mix of IN 1 and IN 2 .In this case the FADE control acts as an Offset control, so that we can add a bias voltage to the incoming CV voltage. As the CV level pot is an attenuverter we can also use negative going CV voltages here too.

In Mode 2, if we use OUT R instead of OUT L, then the mode of operation is reversed, i.e. the mix of IN A and IN B will now cross fade in the opposite direction..

The input signal can be either Audio or CV voltages, since the inputs are DC coupled they can be used for both purposes. We can also patch an audio signal to the CV input, and in this case we can generate some interesting ring modulation and cross modulation type sounds.

 

Mode 3 Stereo Panner

 

In mode 3 the channel operates as a one in, to two out stereo panner. Here we can pan a single input signal between the Left and Right outputs.

We can also use Mode 3 without a CV input, and in this case with the FADE control at zero, 100% of the signal will be routed to the Right Output and zero at the Left output. As the Fade control is rotated clockwise this pans from Right to Left. When the Fade control is rotated fully clockwise we will have zero signal at the Right output, and 100% of the signal at the Left output. Patching a control voltage to the CV input allows voltage controlled panning, and it works in the same way as described in Mode 2, except that obviously now we are panning rather than cross fading.

In Mode 3, if we use IN B instead of IN A, then the mode of operation is reversed, i.e. the panning will now go from a right to left direction.

Again, with Mode 3 we are not limited to panning audio signals; we can patch a Control Voltage such as an LFO etc to the input, and in this case it can be faded to the inputs of two different modules. For example, we could patch the L Out to the Exp CV Input of a VCO, and the R Out to the FCV input of a filter, then by panning from Left to right we can fade between oscillator vibrato and a filter wah wah effect.

Do note that the panner uses a standard (rather than compensated) Panning Law, so the perceived level of sound drops when panning is in the centre position. However, we have partially compensated for this in the design so that the centre drop is only around 2 to 3dB, which is generally acceptable for modular use where we are often using quite different signals for the Left and Right channels.

 

Mode 4 Cross fading Panner

Mode 4 is a combination of modes 2 and 3. The Left output is a crossfade from IN 1 to IN 2, and the Right output is the reverse of this, so it crossfades from IN 2 to IN 1. For example, if we patch a triangle wave from an LFO into the CV Input, then we get a "ping pong" effect as the left and right channels sweep both their panning simultaneously and swap sides. Alternatively, a square wave LFO could be used to get more dramatic Left to right channel bouncing.

We can also use an external CV of between 0 to +5V to select waveform by patching into the WAVE input, and when the Bank select switch is set to EXT-CV position we can select between bank 1 and bank 2 by patching a Gate or CV to the BANK Input.

Again, we can use audio rate CV modulation for added fun, and it is also DC coupled so we could use this to "swap over" between two modulation sources.

 

Putting it all together

Let's now look at how to use it as a Four into Two into One Cross Fader.

Channels 1 and 2 are identical, however channel 3 is functionally the same, but includes some added features. Inputs 3A and 3B each have a level control, and the Left outputs of Channel 1 and Channel 2 are normalised to inputs 3A and 3B, so if we don't patch anything into these two inputs they are fed from the outputs of Channels 1 and 2. This creates a two into one arrangement as shown below.

We can see from this arrangement that we can cross fade between four audio sources that we patch into Inputs IN 1A, IN 1B, IN 2A and IN 2B. We can use the Fade 1 control, or a control voltage to CV-1, to cross fade between these, and this mix is passed to IN 3A. Likewise, the mix of IN 2A and 2B is changed by adjusting the Fade 2 control, or a control voltage patched to CV-2.  Now we can control the individual levels of these two mixes with the Lev 3A and Lev 3B controls, and cross fade these two mixes. This can be a mono signal from Out L-3, or we can pan the mix across a stereo field by using both Out L-3 and Out R-3 together for a stereo mix.

 

 

Block Layout

 

Specification

Effective CV Range for CV-1, CV-2 and CV-3 is 0 to +5V with attenuverter fully clockwise or 0 to -5V with attenuverter fully anticlockwise.

Maximum permissible CV Range for CV-1, CV-2 and CV-3 is -12 to +12V

IN 1A to IN 3B Input levels -5V to +5V, levels up to +/-10V are possible however some clipping may occur.

Module Width: 14hp

Module Depth: 26mm (Including power lead)

Current Usage: 80mA Positive, 72mA Negative

 

 

 

 

Video - Introduction to the Triple Cross

This video gives an overview of the features of the Triple Cross Fader & Panner.

 

 

Demo by Ian Boddy

Here's Ian Boddy himself discussing the reasons behind the creation of the Triple Cross module, and a taster of some music that he has created with it.

 

 

Circular / 3D Panning with the Triple Cross

Here we show how to use stereo panning and cross-fading simultaneously, alternately raising and lowering the volume of 1 or 2 incoming audio signals, whilst moving them between left and right outputs. This can be used to create a 3D impression a sound that is moving in a circular motion.

This might more often be useful fo creating momentary effects, and could be especially interesting for ambient drones, but here we demonstrate it using a sequencer, and eventually 2 melodic synth voices playing different patterns.

An important element in this patch is the modulation - we use the Dual LFO +VCA module to create a quadrature triangle LFO, so I have 2 triangle waves running at the same speed, but at a 25% (or 1 quadrant) difference in their duty cycle - this is achieved by using the square wave of one LFO to sync the other.

 

 

Availability

In production and available now.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Copyright © 2014 AJH Synth