Kawai Synthesizer 100F / Teisco S-100F

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"The Synthesizer 100-F is a very good and classic single-vco monophonic analog synth. It has a small but usable 3-octave, 37-note, C-C keyboard. Sawtooth, square and noise waveforms and external sounds can be run through the synth's filters and envelopes and mixed with the oscillator. Also made under the badge of Teisco, the S-100F has a single oscillator with a very wide range, selected via a 7-position knob (2', 4', 8', 16', 32', 64' and "low").

Although there is only one oscillator, there's plenty of modulation ability to really liven up the sound. There's an LFO which can modulate the VCO, VCF and VCA. The VCF resonant filter is good and can be modulated by the LFO, Envelope 1, the external input or even the VCO! There's also a VCA section with Attack, Decay, Sustain and Release controls and finally there's a Hi-Pass filter. There is also a portamento effect for that final crucial analog synth effect! A typical analog synth with just about all the features and functions you'd need. It's got the classic wood side panels and a front panel layout that leads to very straight forward programming resulting in good analog bass, lead and synth sounds.

The Kawai Synthesizer-100F is a single VCO monophonic analogue synthesizer with a .

A slider controls tuning within the octave. Available waveforms are sawtooth and square, which can be mixed with either noise or an external audio signal. The VCO can be modulated by either envelopes or the LFO, with a slider controlling delay. The VCF section has sliders for cutoff frequency and resonance (called "peak"). The filter can be modulated by the LFO, Envelope 1, the external input, or the oscillator (sawtooth or square waveforms).

The amplifier can use its own envelope generator, Envelope 2, or a simple keyboard gate, and has its own gain slider in addition to the main volume slider. A simple high-pass filter is also available at the end of the audio chain, with a slider controlling filter cutoff. Both of the envelope generators have a three-position switch for envelope type and a slider for attack and one for decay. The first switch position creates a simple AD (attack decay) envelope. The second turns the envelope into an ADS (attack decay sustain) where the sustain is set at about 75% and there is no release value.

The third creates an ASR (attack sustain release) envelope where the sustain is at full value. A switch between both envelope sections chooses between keyboard and LFO triggering for both envelopes. There is a three-mode portamento (not sure what the modes are) with a slider controlling lag amount. The LFO section has a slider for rate and is switchable between sawtooth, triangle, and square waveforms."