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3rd Wave User Manual
The Wave Surfer
About Wave Flow and Upper Wavetables
The PPG 2.2 and 2.3 didn’t have interpolation when switching between
waveforms in the wavetable. In addition, they didn’t stop if you modu-
lated past the 64th position in the wavetable, (0 to 63). To accomodate
this, the PPG had what was called an upper wavetable, (wavetable P30),
which you would spill over to if you modulated past the end.
In addition, every PPG wavetable actually only had 60 waveforms that
were different — and the last 4 waveforms were always triangle, pulse
width square, normal square, and sawtooth. Since these 4 waveforms
have nothing to do with the rest of the table, if you went beyond the end
into the upper wavetable, a click/discontinuity would occur as you went
through positions 60 to 63.
On the 3rd Wave this only applies to “P” wavetables, which were derived
from the original PPG wavetables. If you don’t want to this boundary
and walk into wavetable P30 as you would on the PPG, turn of the
use
upper wavetable option by pressing the wave flow button. In the screen
that appears, use soft knob 1 to set this to off. When off, the 3rd Wave
will only sweep through the rst 60 wave positions then stop without
going into the 8-bit upper wavetable “analog” waveforms.
Note that the “U” waves don’t have this oddity. They extend to 64, (0 to
63), then stop with any upper wavetable waveforms.
You can test this by moving one of the PPG factory patches using the
Wave Surfer knob. It will show you the offset number. When you reach
60 to 63, you will hear the waveform change drastically on any of the P
wavetables as long as that Upper Wavetable function is turned on.
Finally, the”A” waveforms, which are analog modeled waveforms,
are not the 8-bit PPG-style waveforms, but correct spline-interpolated
models. If you want to use high-resolution, high-delity analog wave-
forms, use these. But if you want to use 8-bit PPG emulations of analog
waveforms use the last 4 positions in the “P” wavetables. They will
sound harsher (with aliasing and imaging), but that might be what you
want. Remember to turn off the wave envelope if you want to use one of
these last 4 as an “analog” waveforms. Set the wave offset from one of
the positions from 60 to 63, turn off the wave envelope, and the wave-
form position will not move. You now have a classic, 8-bit aliased, PPG
“analog” waveform.
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