
GUS extended patches

                patch layout:

Patch header
-----------

bytes:  info:           starts at offset:

22      magic                     0
60      copyright                22
 1      instruments              82
 1      voices                   83
 1      channels                 84
 2      number of waveforms      85
 2      master volume            87
 4      datasize                 89
 7      "SF2EXT\0" magic         93 (new)
29      unused                  100
 2      instrument number       129
16      instrument name         131
 4      instrument size         147
 1      number of layers        151
 1      number velocity layers  152 (new)
36      9 layer records of      153 (new)
          4 bytes each:
        velmin/velmax/left-samples/right-samples
 3      unused                  189
 1      layer duplicate         192
 1      layer number            193
 4      layer size              194
 1      number of samples       198
40      10 layer records of     199 (new)
          4 bytes each (continues above array):
        velmin/velmax/left-samples/right-samples

                                239 bytes total
Sample header
-------------

bytes:  info:           starts at offset:


 7      sample name               0
	Name ends in L, R, or M depending on whether the
	sample is for the left channel, the right, or is mono.
 1      fractions                 7
 4      length                    8
 4      loop start               12
 4      loop end                 16
 2      sample rate              20
 4      low frequency            22
 4      high frequency           26
 4      base frequency           30
 2      finetune                 34
 1      panning (7)              36
 6      envelope rates           37  |
 6      envelope offsets         43  |  18 bytes
 3      tremolo sweep/rate/depth 49  |
 3      vibrato sweep/rate/depth 52  |
 1      sample mode              55
 2      scale frequency          56
 2      scale factor             58
 2      sample volume            60 (new?)
 1      volume envelope delay    62 (new)
 1      exclusive class          63 (new)
 1      vibrato delay            64 (new)
 6      mod envelope rates:      65 (new)
         attack/hold/decay/release/relB/relC
 6      mod envelope levels:     71 (new)
         attack/hold/decay/release/relB/relC
 1      mod envelope delay       77 (new)
 1      chorus effect send       78 (new)
 1      reverb effect send       79 (new)
 2      resonance                80 (new)
 2      cutoff frequency         82 (new)
 1      modEnvToPitch            84 (new)
 1      modEnvToFilterFc         85 (new)
 1      modLfoToFilterFc         86 (new)
 1      keynumToModEnvHold       87 (new)
 1      keynumToModEnvDecay      88 (new)
 1      keynumToVolEnvHold       89 (new)
 1      keynumToVolEnvDecay      90 (new)
 1      panning (0-255)          91 (new)
 2      lfo rate	         92 (new)
 1      lfo depth	         94 (new)
 1      aps parameter            95 (new)
  (sample data follows)

                                 96 bytes total
