The Iotine Core 4 comes equipped with two audio inputs, which can be flexibly routed to the device’s three channels. In addition, there is an audio / gate input for controlling the envelope and an audio / CV / gate socket connected with the envelope follower. On the output side, there are individual outs for all three channels plus a mix socket. As the name suggests, this connector emits the sum of all three signal paths.
The user interface of the Iotine Core 4 is divided into five areas. Let’s start with the two modulators on the left:
- Env – The envelope of the Iotine Core 4 comes equipped with Hold, Attack and Release parameters. You can select either one of the audio inputs or the Env input (audio / gate) to control the envelope. Via a switch, it is possible to choose between normal operation and a loop mode. A threshold potentiometer determines how hot the signal level must be to start the envelope. Using a switchable high-pass filter, you can make the modulator immune to high-energy basses.
- EF – The envelope follower features Gain, Attack and Release knobs. Using a switch, it is possible to alter the general behavior of the modulator from fast to moderate to sluggish. An audio input or the EF socket (audio / gate / CV) can be used to control the envelope follower. A Threshold potentiometer, this time with two modes of operation, determines the sensitivity of the envelope follower.
The two “main channels” are composed of a filter, a saturation stage and a VCA. In detail, the following features are available:
- VCF – A resonant multimode filter with a slope of -12 dB per octave. Low-pass, band-pass or high-pass operation can be selected via a switch. Furthermore, you are able to choose whether audio material fed to the first or second input is processed. Incoming signals can be leveled via a potentiometer. Envelope, envelope follower or a 3.5 mm CV input may be used to influence the cutoff parameter. The strength of these modulations can be adjusted via a bipolar attenuator with a three-stage fine-tune switch.
- SAT – A flexible, excellent sounding saturation stage with editable drive, a three-stage dry / wet toggle switch and a level control at the output. Seven different saturation and distortion modes are available per channel. In total, there are 14 different “tastes”, some of which differ greatly in sound. For example, you can discover harmonic distortion, overdrive and wave shaping.
- VCA – A voltage-controlled amplifier with a very low noise-floor. Thanks to a bipolar attenuator in the CV path, the circuit can be used as a compressor (Cmp) or expander / gate (Exp).
The third audio channel of the Iotine Core 4 is called Post. It can be used individually or in serial following the first and / or second channel. Post can be utilized as another resonant multimode filter, a frequency divider (Div) or a multiplier (Oct). Via a toggle switch, you can choose a filter type (low-, band- or high-pass) respectively the octave range of the divider / multiplier (1, 2 or 3). The volume at the output is adjustable via a knob. Additionally, the level can be influenced via the envelope or envelope follower. The divider and multiplier circuits have a very strong effect on any audio material. The results sound hard to brute.
So much for the theory… In practice, the two “main channels” are dynamic filters with enormous distortion capabilities. Besides parallel processing of several signals, it is also possible to use the Iotine Core 4 as a multiband device. – Including different modulations and saturation types. An example:
- The mix output of a drum computer is fed to one of the Iotine’s inputs.
- The Mix output of the Iotine Core 4 is used for tapping off audio signals.
- The first “main channel” is switched to high-pass mode with fast, but very smooth filter modulation and low distortion. The result: Hi-Hat, Cymbal and the like will move the filter very subtly.
- The second “main channel” is in low-pass mode with high resonance and beefy distortion. In addition, a strong, slow modulation is added. Result: The “bottom” gets a pushing, chirping character.
- For additional fun, add multiplier or divider of the Post section. – Please note: Not suitable for tender minds! Thanks to routing switches and level controls for all three channels, you can quickly mute or fade individual components of the signal mixture in and out.
The unit can be either rack mounted or used as a desktop unit because of its angled enclosure.
Two audio inputs
Multifunctional Env and EF inputs
Cutoff CV input
Three individual audio outputs (1, 2, Post)
IEC power input
19" unit, 3U high
482 x 160 x 133 mm (W x D x H)