The GS e7 interface was designed to be simple and intuitive.
It also has MIDI connections, USB, balanced stereo audio outputs, headphone output and CV inputs.
Signal path
The signal path is completely analog, featuring two VCO per voice, a white noise source, a mixer, a 4-pole low pass VCF and a VCA. The control voltages are digitally generated, including 3 LFO, 2 ADSR-type envelope generators. Finally, it has a stereo digital effects processor with Delay and Chorus. LFO 1, LFO2 and the delay can be synced with the MIDI clock using a user selectable subdivision.
Oscillators
It features two VCO plus sub oscillator per voice. Each oscillator has 3 different waveforms: triangle, sawtooth and saw-tri (triangle+sawtooth). There is a fine-tuning adjustment and a transpose option, allowing tune adjustment up to +/- 2 octaves. Tuning can also be modulated with any of the three LFOs and EG1.
Furthermore, each oscillator has a pulse wave that can be turned on or off, which is mixed with the other waveforms. Its pulse width can be modulated with LFO1 and/or EG1.
Oscillators can be hard synced, with oscillator 1 being the master and oscillator 2 the slave.
The autotuning algorithm takes about 2 seconds to complete. All the voices are tuned in parallel, making a lot faster than usual.
Mixer
The mixer can control the levels and mix the two oscillators, the suboscillators and the white noise or the external input (when the external input is connected, the white noise is disabled).
Filter
The filter is a 4-pole ladder-type low-pass filter with resonance control. It can be modulated with EG1, this modulation an also be affected by velocity. It can also be modulated with any of the 3 LFOs. On the other hand, it features keyboard tracking and it can be controlled by the modulation wheel or aftertouch.
Chorus
There are two types of chorus available: basic and ensemble. The Basic algorithm is subtle and allows you to add some spatiality tothe resulting sound, while the Ensemble algorithm adds a different dimension to the sound, simulating a string or vocal ensemble. The Basic algorithm uses two delay lines, while the Ensemble uses 4 delay lines. Each delay line has its own internal LFO. There are controls for rate, depth and mix.