Overview
XS-1 Synth Architecture

XS-1 synth architecture

PCM/DC Waveforms
Basically, XS-1 is a PCM playbacker synthesizer without a filter, like Roland U-110 and YAMAHA TG100. XS-1 has two groups of waveforms called PCM and DC. It seems to have 1MB ROM.
One of XS-1's advantage is that it has many DC synthetic waves.

PCM waveforms are a little bit longer samples and some of them are multi-sampled.
DC (Digital Cyclic) waveforms are essentially single cycle loops. KAWAI sampled many instruments, and analyzed the samples using their additive synthesis technology. They converted the samples into up to 128 sine harmonic waves, and newly made single cycle loops from these cluster of sine waves. DC waves are multi-sampled and sounds stably all over the keyboard range.
Oscillator and DCA
There are two oscillators in a Single Patch. There are 128 sets of waveforms like "Piano&Ride" and "Violin&Random." Two waveforms are set at once to the two oscillators.
There's no detune functions. Only their volumes can be conrolled individually, and different DCA envelopes can be set.
Instruments are 10 voice polyphonic.
LFO, etc.
LFO can add vibrato and it has 4 waveforms.
Auto Bend can modulate the pitch, and it works on all the voices at once.
There is a preset drum kit, and it has 4 polyphony.
Multi Patch can combine 4 Single Patches with transposing and detuning.
There's no effects.
Features
XS-1 has some features that go beyond the simple PCM playbackers.
XS-1 can add distortion to the sounds when the volume is set high.
There are strange waveforms that playbacks the ordinary samples in different ways.

Some Jam Loops plays back several samples in sequence like Roland D-50 / D-110 / MT-32.
Some samples are relooped back and forth to make a different version. XS-1 is a rare synth that has some preset waveforms with intended loop noise.
There is a waveform which plays back all the DC multi-samples at once. This feature is inherited from KAWAI K4. Ensoniq VFX / SQ-R series are the rare synths except KAWAI that can produce such sounds.



Next XS-1/Spectra

Deep Synthesis: Home

8. 5. 2003
modified: 8. 25. 2004