6.2.4.1 NzFil = Noise Filter < 000-127 >
After the noise level control there is a simple 6 dB/octave low pass filter which can
make the noise a bit more dull. A strong filtering of noise with a 6 dB/octave filter is
also known as “pink noise“. The noise loses its sharpness if you lower this value. At
<127> the filter is opened and lets all high frequencies pass through with a slight mid-
peak at 4kHz.
At <000> the noise signal is turned off.
6.2.4.2 MtNz1 = Metal Noise 1 < 000-127 >
Metallic noise 1 is one of two noise generators which offers a more periodic (tone-like)
metallic noise algorithm. The basic character of noise 1 can be varied a lot by an
adjustable bit mask (which applies only to noise 1).
Both noise generators get mixed by hardware. Therefore the noise level increases
significantly if both noise generators are on. The signals interfere and then produce new
noise patterns. The parameter changes the noise to a metallic noise which consists of
periodic asyncronous bit patterns. With <000> the noise generator is turned off, <001>
produces a static random noise (white noise).
On values above that <2-127> a complex signal formed from digital multitones and bit
patterns is produced. Each value represents a unique sound pattern which doesn't
change smoothly across the range but jumps to various sounds one by one, more akin
to a kaleidoscope than a linear scale. They give you interesting results for any
adjustment, so play the game of trial and error!
Metallic Noise 1 is more periodic and has an adjustable bit mask.
Metallic Noise 2 yields a more aperiodic signal which results in more noise-like sounds.
This is useful for eg. cowbell-like sounds.
6.2.4.3 NzShp = Noise Shape < 000-012 >
This parameter defines the bit mask for noise generator 1. Small values produce very
high frequencies in combination with the metallic noise 1 parameter, high values
produce longer periodic signals. To hear changes on this parameter please check that
metallic noise generator 1 isn't turned off. With low values for bit mask some numbers
of metallic noise may produce silence by phase cancellation or may sound the same
with every consecutive number so that only the lower numbers are relevant.
40 ALPHA BASE Operating Manual