Model Parameters - Kurzweil K150 - APPENDIX 1 Appendix

0
-4
dB
-8
-12
-16
-20 300, -16
300
Below is a spreadsheet showing how the values in the example above were calculated:
BREAKPOINT
NUMBER
1 300,-16
2 400, -4.56
3 450,-13.14
4 550, -7.42
5 600,-20.30
1.5.5 Partial Phases
No control over the phases of partials is offered by the K150FS. The operating software attempts to set all of the phases to
zero in order to minimize clicks on fast attacks. However, for high frequency partials, delays in getting them started relative
to other partials will result in noticeable (on an oscilloscope) deviations from zero phase. In any case, the 0.298Hz frequency
quantization will generally cause the phases to drift slowly while a note is held, even when exact harmonics are specified.
This effect may be easily seen by playing the built-in sawtooth voice (#253) or generating the .S.M.P. default voice which is
a 16 partial sawtooth. Of course the whole issue of phase is moot for sounds with intended inexact harmonics.

1.6 MODEL PARAMETERS

Model parameters affect the entire sound model in some fashion.
1.6.1 Model Name
The model name is 8 uppercase ASCII characters. Short names may be padded on the right by either blanks or zeroes. Since
we are dealing with models rather than voices, the model name will never appear on the K150FS display and thus serves no
useful purpose except if the model is read back out of the K150FS's voice RAM.
1.6.2 Highest Note
When two or more models are combined into a voice, this parameter specifies the highest MIDI note number the model can
play. The lowest note is one higher than the highest note of the previous model. The first model however can play down to
C0 while the last model can play up to C8 regardless of this parameter.
1.6.3 Ignore Release Flag
For a sound that must play its contours to the end regardless of when the MIDI note-off is received (example: undamped
bell), this flag should be set. To avoid an abrupt termination of partials when the End-of-Note command is reached, they
should all have decayed to silence first. With this flag set, release slopes have no meaning since there is no release. This flag
should not be set if a Loopback command is present; if it is, End-of-Note will never be reached and the contours will loop
forever.
400,-6
-4.56
114.4 dB/s
100 dB/s -171 dB/s
350 400
INITIAL DESIRED
POINT ENDPOINT
400, -6
450,-12.5
550, -9
600,-20.5
550,-9
57.2 dB/s
450,-12.5
-13.14
450 500 550
msec
DESIRED
SLOPE
100.0
-158.8
41.4
-261.6
-7.42
-257.5 dB/s
600,-20.5
-20.3
600 650
ACTUAL ACTUAL
SLOPE ENDPOINT
114.4 400, -4.56
-171.7 450,-13.14
57.2 550, -7.42
-257.5 600,-20.30
Desired
Actual