


MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
________________________________________________________________________



           Public file MODFIL10.TXT - Version 1.0 - by Thunder


Introduction
_______________________________

What this file attempts  to do is describe  the MOD format in  detail and
elaborate on the 'effects' that are possible.  This is the  first version
of this file, so if there are mistakes (and I expect at  least a couple),
please let me  know.   This information was  compiled from  a variety  of
sources, many  of them  anonymous, so  I will  thank them  all, and  they
hopefully know who they are.  I would like to keep this  file up to date.
It will be posted as 'MODFILxx.TXT' or 'MODFILxx.ZIP', where 'xx'  is the
version number (MODFIL10.TXT being the first release).

I assume that you  have some prior knowledge  of some 'technical'  terms,
including: sample, channel (or voice), frequency, logarithmic  vs. linear
volume, byte,  word,  long integer,  and  hexadecimal  format.   It  also
assumes  that  you  know  something  about  the  machine  that   you  are
programming on.   If you do  not know  these things,  this file will  NOT
teach you them.  Refer to other sources before going further.

I am a  PC programmer, so  I cannot  elaborate on particular  procedures,
routines, methodologies,  or  tricks  that  can  be  performed  on  other
architechtures.  I have written routines for the Gravis UltraSound,
which is probably the easiest sound card (on the PC anyway) to  write MOD
routines for.

I disclaim everything  in this file.   This information  is for your  use
personally, but I  don't care  if you  give it  to everyone  else on  the
planet.   I would  like the  file  to stay  intact, and  if  you use  the
information a 'hello' to me in your program's credits would be nice.   If
the information is wrong or gives you problems or damages  your equipment
or person, tough luck.   I am  not responsible for  anything you DO  with
this information.

If you have additions, corrections, clarification or questions about this
information or this file, you can send them to me through the internet to
'kurt.kennett@gravis.com' or 'kurtt@sfu.ca'.

Here is an overview of what is in this file:

1 General
2 File Format
  2.1 Song Name
  2.2 Sample Information
  2.3 Number of patterns in song
  2.4 Song end jump position
  2.5 Pattern table
  2.6 File format tag
  2.7 Patterns
  2.8 Sample data

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MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
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3 Playing the files
  3.1 Timing
  3.2 Periods
  3.3 Fine-Tuning
  3.4 Effects
  3.5 Other information
4 Period and Volume tables



1.0 General
___________________________________________

Files with the  extension '.MOD'  are sequenced  music files.   The  file
format has it's  roots in  the Commodore  Amiga computer  (ugh!).   These
files use different  digital 'samples' played  at various frequencies  to
create three  octaves  of  'notes'  for  that sample.    In  addition  to
different 'notes', there  are a large  number of  'effects' which can  be
done to produce variations on the different notes.

There are many variations on the MOD format.  Since the format originated
on the Commodore Amiga computer, the files were geared towards  a machine
with  4 voices.  These days, with a GUS (Gravis UltraSound),  you have 32
independent voices.  If you are  programming for a sound board  or device
that has only 1 or 2 digital voices, you will have to  mix together the 4
to 8 output channels into those voices.  I will not go  into this process
here, since I do not  have experience with it  (you don't need to  mix on
the GUS).  If someone would like to mail me a TEXT explaination of how to
do the mixing, I  will include it in  this file.  I  DO NOT WANT CODE  --
learn how to write english.

The earliest versions of the MOD format used a maximum of  15 instruments
and had 4  channels.   Through some  modifications in  format, a  'newer'
standard emerged, with a maximum of 31 instruments and up to  8 channels.
You can tell what format of file you are working with by a four-character
tag field.  The programs that are  used to play these files on  the Amiga
are called 'Noisetracker', 'Soundtracker', and 'Protracker'.



2.0 File Format
_______________________________

What follows is a description of  a file broken down in  a field-by-field
format.  This is  just a general description.   Please see the  following
subsections for a detailed description of what each field is and  what it
means.

'Big-End Word' refers to the word format on the Amiga.  A  2-byte integer
value  is  a  word.    On   the  Amiga,  this  value  has   the  internal
representation HHLL, where HH means the high-order byte and LL  means the
low-order byte.  The Intel chips (inside PCs) use a LLHH format for their
words.  This means that if you are writing routines for the  PC, you have
to flip the high and low order bytes to retrieve meaningful values.

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MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
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Just to piss  off all  the C  programmers, I'm  going to  start the  file
offset at 1 instead of 0.

 Offset   Length   Format    Description
======== ======== ========= =============
      1       20   Chars     Title of the song.  If the title is not a
                             full 20 chars in length, it will be null-
                             terminated.

     21       22   Chars     Sample 1 name.  If the name is not a full
                             22 chars in length, it will be null
                             terminated.

     43        2   Big-End   Sample 1 length in 2-byte words.  Multiply
                   Word      this value by 2 to get the length of the
                             sample in bytes.

     45        1   SNibble   Sample 1 finetune.

     46        1   Byte      Sample 1 linear volume.

     47        2   Big-End   Sample 1 repeat offset in 2-byte words.
                   Word      Multiply this value by 2 to get the position
                             in bytes.

     49        2   Big-End   Sample 1 repeat length in 2-byte words.
                   Word      Multiply this value by 2 to get the length
                             in bytes.

     51       30             Sample 2 information.  Same format.
     81       30             Sample 3 information   Same format.

     .        There will either be 15 or 31 sample information blocks.
     .        See the format tag field below for a description of how
     .        to find out how many instruments there are.  We'll go on
     .        the assumption that there are 31 instruments in the file.

    921       30             Sample 31 information.

    951        1   Byte      Number of patterns in SONG as played.

    952        1   Byte      Song end jump position.

    953      128   Bytes     Pattern Table.  These list up to 128
                             pattern numbers and the order they should
                             be played in.

   1081        4   Chars     File format tag.

   1085 ... Pattern and Sample data.  Please see pattern section and
            sample section for more information.




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MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
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2.1 Song Name
_______________________________

This data is pretty  self-representative.  This is  a C 'string' that  is
null-terminated (i.e. ASCII character 0 is put at the end of the  text is
the text does not  fill up the  entire field).   Some module writers  use
this field and the  instrument name fields to  write 'hello' messages  to
their friends or dedications instead of giving names to the song  or it's
samples.  I in no way discourage this.



2.2 Sample Information
_______________________________

Based on the format tag field, there can be 15 or 31  sampled instruments
for the song.  These days it is  rare to run into an 'older'  format song
with only 15  instruments.  Please  see the 'File  format tag' field  for
more information on  how to  determine how many  samples there  are in  a
file.

The first field in a sample  information block is the sample's name.   As
was mentioned above, these names are  frequently used by the  composer to
say hello to his or her friends.  Again, I in no way discourage this.  If
the sample name begins with a '#' character (ASCII $23 (35)) then this is
assumed not to be an instrument name, and is probably a message.

The second field is the sample  length in words.  Once again,  since this
is a 680x0 word, the bytes have the order HHLL, and you have to swap them
to use the word on PCs.  The first 2 bytes of the sample  are used by the
Amiga players for repeat information, and  therefore are NOT part  of the
playable data.  Therefore, if this field is evaluated to a length of less
than 3 bytes, there is NO sample.

The third field is the sample's  initial finetune value.  The  lower four
bits represent a signed  nibble (-8..7). Each  finetune step changes  the
note 1/8th  of  a  semitone.   This  is  implemented by  switching  to  a
different table of period-values  for each finetune  value.  See  section
3.2 for a discussion of fine-tuning.

The fourth  field is  the sample's  playback volume.    These are  LINEAR
values that range from 0 to 64, with 64 being maximum volume.  If you are
implementing a  MOD  player,  remember  to  check  if  you  need  to  use
logarithmic volumes.  'Decibel' is a logrithmical unit,  which represents
how we feel  sound intensity.   The volume  and decibel  value table  for
conversions is on the next page.









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MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
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            Volume  Decibel Value     Volume  Decibel Value
         -------------------------  ------------------------
              64         0.0            32        -6.0
              63        -0.1            31        -6.3
              62        -0.3            30        -6.6
              61        -0.4            29        -6.9
              60        -0.6            28        -7.2
              59        -0.7            27        -7.5
              58        -0.9            26        -7.8
              57        -1.0            25        -8.2
              56        -1.2            24        -8.5
              55        -1.3            23        -8.9
              54        -1.5            22        -9.3
              53        -1.6            21        -9.7
              52        -1.8            20       -10.1
              51        -2.0            19       -10.5
              50        -2.1            18       -11.0
              49        -2.3            17       -11.5
              48        -2.5            16       -12.0
              47        -2.7            15       -12.6
              46        -2.9            14       -13.2
              45        -3.1            13       -13.8
              44        -3.3            12       -14.5
              43        -3.5            11       -15.3
              42        -3.7            10       -16.1
              41        -3.9             9       -17.0
              40        -4.1             8       -18.1
              39        -4.3             7       -19.2
              38        -4.5             6       -20.6
              37        -4.8             5       -22.1
              36        -5.0             4       -24.1
              35        -5.2             3       -26.6
              34        -5.5             2       -30.1
              33        -5.8             1       -36.1
                                         0    Minus infinity

The reason  for  the  table starting  at  0  dB as  the  convention  from
taperecorders of  having 0  dB as  the optimal  recording condition,  and
displaying anything worse as a negative  number.  Please see  section 4.0
for a complete linear volume format for Gravis' UltraSound.

The fifth field  in the  sample information  block is  the sample  repeat
start offset.  Once this sample has been played completely from beginning
to end, if the  repeat length (next field)  is greater than two  bytes it
will loop back to this position in the sample and continue playing.  Once
it has played for  the repeat length,  it continues to  loop back to  the
repeat start offset.  This means the sample continues playing until it is
told to stop.

The last, or sixth field in the sample information is the  repeat length.
A sample is only looped if this value  is greater than 2 bytes.   See the
preceeding paragraph for more information on looping.



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MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
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2.3 Number of patterns in song
_______________________________

This byte represents the number of patterns which are played in the entire
SONG.  This is NOT the number of patterns in the FILE.  The file may
contain (theoretically) up to 256 patterns, whereas the song is just a
selection of those patterns.  If I have 30 patterns in my file, and I just
want to play patterns 6, 12, 3, 7, and 8 in that order, this byte will have
the value 5.



2.4 Song end jump position
_______________________________

Historically, this byte has been used  for many purposes.   Most commonly
in the newer  format it  has been  used to  signify if  a song  is to  be
repeated indefinitely.   Some game programs  have background music  which
never ends.   If  this byte  is  less than  127,  then it  specifies  the
position in the pattern table to  jump to when the last pattern  has been
played.  If this byte is greater than or equal to 127, the song ends.



2.5 Pattern table
_______________________________

This 128 byte block lists the  order that patterns in the file  should be
played in.  Only the number of bytes specified by the number  of patterns
in the song (see section 2.3) can be considered valid.  If the song is to
play patterns 6, 0, 12, 11, 21, and 10 in that order, then the table will
have those 6 values as the first 6 bytes:

                             Pattern Table
  Position --->  0   1   2   3   4   5   6 ---------> 127
               |---|---|---|---|---|---|---|---...---|---|
               |006|000|012|011|021|010|    ?????????    |
               |---|---|---|---|---|---|---|---...---|---|

One of the  effects which  is possible (see  section 3.4)  is a  position
jump.  The argument  to this effect is  where to jump  to in the  PATTERN
TABLE.  This does NOT specify which PATTERN to jump to.

In a particular pattern  there are 64 lines.   These lines are  played in
order from  0 to  63.   When the  end of  a pattern  is reached,  playing
continues with the next pattern in the pattern table, unless  the current
pattern is the last one.  If  the current pattern IS the last  one, check
the song end jump position (see section 2.4) to see if the  song loops to
a certain position  in the  pattern table.   Another one  of the  effects
which is possible (see section 3.4)  is a pattern break.  If  this effect
is encountered, playing immediately jumps to  the first line of  the next
pattern.



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MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
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2.6 File format tag
_______________________________

This is the most  controversial field in the  file.  This field  has been
the most 'ravaged', with  many people using it  in non-standard ways  for
their own purposes.   There are a  few standard tags  which you can  find
here which tell you  DEFINITELY what file format  the file is, but  there
are many more  non-standard tags.   This makes the  job of deciding  what
format a MOD is a  difficult one.  I  will attempt to describe  the known
formats below.  If you know of one I miss, please let me know.

     'M.K.', 'FLT4',
     'M!K!', '4CHN' : 4 channels, 31 instruments

     '6CHN'         : 6 channels, 31 instruments

     '8CHN', 'OCTA' : 8 channels, 31 instruments

Other information  that is  found in  this  field can  be assumed  to  be
somebody's attempt at protection, or some other information that was used
in the  'older'  file  format.   If  you  can't find  any  of  the  above
information, it is best to assume that it's a 4 channel file.  As for how
many instruments there are, check the bytes at location 471 in  the file.
If there is text  there (ASCII $20-$7E (32-126)),  then you can  probably
assume it's a 31-instrument file.  Otherwise, it's an older 15 instrument
file.



2.7 Patterns
_______________________________

There can be any number of patterns  in the file.  They are  stored after
the file header and before the sample data.  There are USUALLY  less than
64, but the maximum is not limited - if the file tag  is 'M!K!' there are
definitely more than 64 patterns.

The patterns are stored sequentially (i.e.  the first pattern is  #0, the
second pattern is  #1, etc.).   An individual  pattern is  made up of  64
'lines', stored sequentially (i.e.  line 0 to line  63).  Each 'line'  is
comprised of a note for each channel.  Each 'note' is made up of 4 bytes,
so depending on the number of channels in the file, there are  16, 24, or
32 bytes per line.

For a four-channel file there are (4 bytes * 4 channels * 64 lines) =1024
bytes of information per pattern.  To find out the number of  patterns in
a particular file, calculate the  length of 'header' information  and add
to it  the  lengths of  all  samples that  are  mentioned in  the  sample
information blocks.  Subtract this number from the file's total  size and
divide by the number just computed  (1024) to get the number  of patterns
in the file.




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MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
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As mentioned above, each note is stored as 4 bytes.  The information held
by these bytes has format shown  below.  How you display the  contents of
the 4 bytes in  a player is up  to you.  There  is NO standard way  to do
this.

               Byte  1   Byte  2   Byte  3   Byte 4
              --------- --------- --------- ---------
              7654-3210 7654-3210 7654-3210 7654-3210
              wwww XXXX xxxxxxxxx yyyy ZZZZ zzzzzzzzz

                  wwwwyyyy ( 8 bits) : sample number
              XXXXxxxxxxxx (12 bits) : sample 'period'
              ZZZZzzzzzzzz (12 bits) : effect and argument

The sample number refers to a sample specified in the  sample information
block.   Please see  sections 2.2  and 2.8  for more  information on  the
samples.

The sample 'period' corresponds  to a delay value  on an Amiga  computer.
Note that on  an Intel  processor, you  have to  order these  12 bits  as
'xxxxxxxx0000XXXX' to read the value as a word.  Please see  sections 3.2
and 3.3 for more information on how to use these values.

The effect is an  effect number and an  argument for the effect.   Please
see section 3.4  for a  discussion of the  effects and  how to  implement
them.



2.8 Sample data
_______________________________

The sample data  follows all of  the patterns.   After you have  finished
reading the pattern data, there will be just enough data left in the file
for all of the instruments  specified in the sample  information section.
The samples are  stored sequentially  from sample 1  to sample  31.   The
sample's data is in 8-bit two's  compliment format, so if it needs  to be
in another  format for  your sound  device to  play it,  don't forget  to
convert (UltraSound  users:  you don't  need  to  convert the  data  when
downloading).

As was mentioned in section 2.2, the first 2 bytes of the sample are used
by the Amiga MOD  players for repeat information,  and therefore are  NOT
part of the  playable data.   PC users do  not have  to do anything  with
these two bytes.










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MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
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3.0 Playing the files
_______________________________

Section 3 deals  with playing  MOD files.   Specifically,  it deals  with
playing them  on  PC  hardware -  hopefully  a  Gravis UltraSound.    The
Ultrasound is  ideal for  this and  many other  types of  sound and  song
processing, and is exceptionally easy to program.  Gravis makes available
an SDK (Software Development Kit) which has both C, C++, and (by  the end
of November)  Borland Pascal  versions.   If you  are  programming a  MOD
player for other hardware, you may still be able to use  this information
for reference.



3.1 Timing
_______________________________

If lines are played  sequentially, then how long  should the player  wait
between successive lines?  On the Amiga, the amount of time a note spends
on a channel before the next note is started is calculated by  using some
complex formulas based on  the PAL color carrier  frequency.  I will  not
try to bore you with the  details of these calculations here, and  if you
wan't them, email me.

A song can be played at  a speed ranging from  1 to 127, where  the speed
specifies how many  'ticks' before playing  the next sample.   A tick  is
supposed to happen every .02 seconds, which gives 50 ticks per second.

At the start of  a line all samples  specified on that line  are started,
samples playing  are  modified, speed  is  changed,  etc.   Some  effects
require that changes be made to a sample playing on a channel  during the
course of a line.  For  example, the retrigger effect re-starts  a sample
at a certain tick within a line.  If  the song is playing at speed  6 and
the effect specifies a retrigger on the 4th tick:

               Time Tick
               0.00  1 - start all samples and effects
               0.02  2
               0.04  3
               0.06  4 - retrigger sample here
               0.08  5
               0.10  6
               ------------
               0.00  1 - start next line
                   .
                   .

Unless a speed is specified on  the first line of the first  pattern, the
song should start playing at speed 6.  Please see section 3.4, effect $F,
for more information on changes in speed.





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MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
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3.2 Periods
_______________________________

MOD  players  use  a  technique  called  frequency  shifting  to  produce
different 'notes' of the same sample.  If  I play a sample at 10  KHz, it
will sound one octave higher if I double the frequency to 20 KHz, and one
octave lower if I halve the frequency to 5 KHz.  Since there are 12 notes
per octave on a  keyboard (these are  called half-steps), each  frequency
corresponds to one twelfth root of two (~1.05946) times the  frequency of
it's predecessor (to  the left).   Therefore, if  the C-1 frequency  (the
note of C in octave 1) is 4144 Hz then:

Note: C-1  C#1  D-1  ... C-2  ...
Freq: 4144 4390 4651 ... 8288 ...

The Amiga playing routines were  written to run off  different interrupts
for different Amiga computers, based on whether the machine was a  PAL or
NTSC machine.    The  'period' values  are  measures  which are  used  in
calculating how much data  to send to  each of the  4 Amiga channels  per
second (thereby specifying the frequency or pitch of the output).

For PC programmers, you  don't have to worry  about this that much.   The
thing to remember is  that a 'magic number'  divided by twice the  period
value will give the rate (frequency) to play the sample at.  Here are the
magic numbers and the corresponding formulae.  I don't know  which number
is better to use - It doesn't make a huge difference.

               PAL Value                NTSC Value
              ===========              ============

                7093789.2                       7159090.5
SampleRate = --------------     SampleRate = --------------
               Period * 2                      Period * 2

To determine what frequency  to play a sample  at, look up the  specified
period value in a  table based on the  finetune setting (see section  3.3
for more  information on  fine-tuning).   If the  period is  0, then  the
previous period used on that channel is used.

As an example, let's look at the period table for finetune 0.   The notes
that are possible in each octave are:

          C    C#   D    D#   E    F    F#   G    G#   A    A#   B
Octave 1: 856, 808, 762, 720, 678, 640, 604, 570, 538, 508, 480, 453
Octave 2: 428, 404, 381, 360, 339, 320, 302, 285, 269, 254, 240, 226
Octave 3: 214, 202, 190, 180, 170, 160, 151, 143, 135, 127, 120, 113

Octave 0:1712,1616,1525,1440,1357,1281,1209,1141,1077,1017, 961, 907
Octave 4: 107, 101,  95,  90,  85,  80,  76,  71,  67,  64,  60,  57

If I was requested to play a  sample at period 302, I would  scan through
the period table until I hit that value.  At that point,  I know that the
note is called  'F#2', F-sharp  in octave 2.   I  calculate the  playback
frequency by doing the calculations on the next page.

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MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
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      PAL Value                     NTSC Value
      ===========                   ============

       7093789.2                     7159090.5
      ----------- = 11745 Hz        ----------- = 11853 Hz
        302 * 2                       302 * 2

There are normally  only three octaves  (1 to 3)  used in playing  songs.
Octaves 0 and 4 are NOT standard.  Some songs may use  the values though,
and it's nice if your player can handle them.  Full period tables for all
finetunes are listed in section 4.

If you wish to sample sounds  to include in MOD files, remember  that the
data must be stored in 8-bit 2's complement format.  There is NO standard
sample rate when creating the samples.   Most often the samples  are done
on the rate corresponding to period C-3 (around 16.5 KHz),  and sometimes
drums are sampled at A-3 (around 28 KHz).

If sample number  is specified on  a channel (sample  #0), then the  last
sample used on that channel will  be remembered if new notes  come along.
Only one sample may play on a channel at a time, so  playing a new sample
will cancel an old one - even if  there is no actual sample data  for the
new sample (a 'silent' sample).   However, if you are constructing  a MOD
file of your own and you  use a "silent" sample  it is polite to  set its
default volume to 0.

If you have some memory (around 2k or  so) to spare, you could make  up a
table of words indexed  by period value.   The value of  the word at  the
index of a period is the  corresponding frequency that the  sample should
be played at.   This saves you from  having to calculate the  frequencies
over and over again.  If you still don't get what I'm talking about here:

I have a array of words, one for each period from the  lowest (around 50)
to the highest (around 1712).  I precalculate the contents of  this table
so that at index 302 (the period for note F#2), there is the value 11853,
the frequency to use to get the note F#2.  Therefore, when my player runs
accross this value and  needs to know what  frequency to play the  sample
at, I simply look up the  value in the table directly -  no calculations.
If you still don't get what I'm talking about, you're screwed.



3.3 Fine-Tuning
_______________________________

Fine-tuning is a minor adjustment on  how an instrument sounds.   This is
implemented by small changes  in the period values.   The finetune  value
for a  sample specifies  the adjustment  on the  period  values for  that
instrument.  A fine-tune can also be specified for a  specific instrument
by an effect, at  which point the value  in the effect will  override the
one in the sample information block.




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MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
________________________________________________________________________

The value in  the sample information  block is a  signed nibble (4  bits,
signed 2's complement).  Therefore, the values that can be found have the
following corresponding finetunes:

Value:    0   1   2   3   4   5   6   7   8   9   A   B   C   D   E   F
Finetune: 0  +1  +2  +3  +4  +5  +6  +7  -8  -7  -6  -5  -4  -3  -2  -1

Section 4.0 specifies period values for all finetunes for octaves 1 to 3.
You could use these values in creating your array of frequency words (see
the end of section 3.2).



3.4 Effects
_______________________________

As was  mentioned  in section  2.7,  the 4  bytes  for  a note  have  the
following format:

               Byte  1   Byte  2   Byte  3   Byte 4
              --------- --------- --------- ---------
              7654-3210 7654-3210 7654-3210 7654-3210
              wwww XXXX xxxxxxxxx yyyy ZZZZ zzzzzzzzz

                  wwwwyyyy ( 8 bits) : sample number
              XXXXxxxxxxxx (12 bits) : sample 'period'
              ZZZZzzzzzzzz (12 bits) : effect and argument

Again, how you display this information in a player is up to you.  I have
seen a  zillion different  formats.   I have  described  what the  sample
number and period refer to.  Here,  we will look at the effects  that are
possible.

At this point  in time, the  Amiga Protracker  MOD player (version  2.3A/
3.01)   has 28  effects.   Some of  these effects  are  redundant or  not
possible on some PC  sound cards.   I will describe  the effects and  how
they are implemented on the Amiga.  PC programmers will have to adapt the
effects they wish to implement on  their own.  All numbers are  stated in
hexadecimal.

For the  discussion of  the effects,  we  will look  at the  'effect  and
argument' part of the 4 bytes in the following way:

               Bit number:         $CBA987654321
               Mentioned above as:  ZZZZzzzzzzzz
               We will use:         ZZZZxxxxyyyy

There are two types of effects,  standard and extended.  All  effects use
the ZZZZ portion to declare the effect number.  Standard effects  use the
xxxx and yyyy portions as one or two arguments, either as an  8-bit value
when taken together in the form  xxxxyyyy or as 2 nibbles xxxx  and yyyy.
Extended effects  have the  ZZZZ effect  number $E.   They  use the  xxxx
portion to  declare the  extended effect  number and  the  only the  yyyy
portion as an argument.

_______________________________________________________________________
                                                                      12



MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
________________________________________________________________________

Here are the possible standard effects:
-----------------------------------------------------------------------
#   Effect name                          Uses Arguments as
-----------------------------------------------------------------------
0   Arpeggio                             xxxx  yyyy
1   Slide Up                             xxxxyyyy
2   Slide Down                           xxxxyyyy
3   Tone Portamento                      xxxxyyyy
4   Vibrato                              xxxx  yyyy
5   Tone Portamento + Volume Slide       xxxx  yyyy
6   Vibrato + Volume Slide               xxxx  yyyy
7   Tremolo                              xxxx  yyyy
8   NOT USED                             n/a
9   Set SampleOffset                     xxxxyyyy
A   VolumeSlide                          xxxx  yyyy
B   Position Jump                        xxxxyyyy
C   Set Volume                           xxxxyyyy
D   Pattern Break                        xxxxyyyy
E   *Extended Effects                    see below
F   Set Speed                            xxxxyyyy


And here are the possible extended effects:
                   ---------------------------------
                    #   Effect name
                   ---------------------------------
                    E0  Set Filter
                    E1  FineSlide Up
                    E2  FineSlide Down
                    E3  Glissando Control
                    E4  Set Vibrato Waveform
                    E5  Set FineTune
                    E6  Set/Jump to Loop
                    E7  Set Tremolo Waveform
                    E8  NOT USED
                    E9  Retrig Note
                    EA  Fine VolumeSlide Up
                    EB  Fine VolumeSlide Down
                    EC  NoteCut
                    ED  NoteDelay
                    EE  PatternDelay
                    EF  Invert Loop


A description of each  effect and how it  is implemented is given  on the
following pages.  Once again, all values are given in  hexadecimal unless
otherwise stated.








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                                                                      13



MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
________________________________________________________________________

-----------------------------------------------------------------------
0: Arpeggio
-----------------------------------------------------------------------
If a note as an effect number of 0, it is only an arpeggio if there is at
least one non-zero argument.  When there is at least one  valid argument,
this effect means to  play the note specified,  then the note+xxxx  half-
steps, then the  note+yyyy half-steps,  and then return  to the  original
note.  These changes are evenly spaced  within the time for a line  to be
played at the current speed.

This effect is usually  used to simulate chords  (where a major chord  is
the note+4 half  steps and the  note+7 half-steps).   This does not  work
very well on  most samples.   This can also  be used  to produce a  heavy
vibrato.  Here is an example of this effect:

Note C-3, xxxx=4, yyyy=7

this will attempt to produce a C-major chord.  At the beginning of a line
the C-3 note is played, then at 1/3 of the way through  the line the note
is retriggered at E-3, 2/3 of  the way through it is retriggered  at G-3,
and at the beginning of the  next line (if there  are no new notes  to be
played on the channel), it is retriggered at C-3 again.

This presents a minor problem for timing, since you have to keep track of
the arpeggio during the course of playing  a line.  What you could  do is
use a  timer differently,  or set  up  another timer  that  independently
tracks the timing of the arpeggio.


-----------------------------------------------------------------------
1: Slide up (Portamento Up)
-----------------------------------------------------------------------
This effect will  slide up  the frequency  (decrease the  period) of  the
sample being played on the channel by xxxxyyyy notes for every  tick that
occurs during the line.   You usually cannot  slide past note B-3  unless
you have implemented octave 4 (NON-STANDARD!).  The number of  ticks that
occur per line is set with effect  $F, the set speed command.   Since the
slide rate depends on  the speed, be careful  if you set are  composing a
MOD when you change the speed.  An example of this effect is:

Note C-3, xxxxyyyy = 2, playing at speed 3.

At the beginning of the line the sample is started at period C-3.  At the
first tick, the period is decremented by 2 (the frequency  is increased).
At the  second tick,  the period  is  again decremented  by  2.   At  the
beginning of the next line, if there is  not a new note to be  played the
period is again decremented by 2.








_______________________________________________________________________
                                                                      14



MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
________________________________________________________________________

-----------------------------------------------------------------------
2: Slide down (Portamento Down)
-----------------------------------------------------------------------
This effect will slide  down the frequency (increase  the period) of  the
sample being played on the channel by xxxxyyyy tones for every  tick that
occurs during the line.  You  usually cannot slide below note  C-1 unless
you have implemented octave 0 (NON-STANDARD!).  The number of  ticks that
occur per line is set with effect  $F, the set speed command.   Since the
slide rate depends on  the speed, be careful  if you set are  composing a
MOD when you change the speed.  An example of this effect is:

Note C-3, xxxxyyyy = 2, playing at speed 3.

At the beginning of the line the sample is started at period C-3.  At the
first tick, the period is incremented by 2 (the frequency  is decreased).
At the  second tick,  the period  is  again incremented  by  2.   At  the
beginning of the next line, if there is  not a new note to be  played the
period is again incremented by 2.


-----------------------------------------------------------------------
3: Slide to note
-----------------------------------------------------------------------
This effect will slide  a note being played  on a channel to  a specified
note.  The parameter xxxxyyyy will states the speed at which a slide will
occur.  For each tick that  occurs during the line, the  period currently
being played is altered by the number of notes specified.  The  number of
ticks that occur per line is  set with effect $F, the set  speed command.
Since the slide  rate depends on  the speed,  be careful  if you set  are
composing a MOD when you change the speed.  An example of this effect is:

Slide to note C-2, xxxxyyyy = 2, playing at speed 3.

At the beginning  of the  line the current  frequency for  the sample  is
altered to  be 2  notes closer  to  C-2.   At the  first  tick, the  same
alteration occurs, changing the period to form a note even closer to C-2.
The same occurs for  each tick after that.   This effect continues  until
another effect is started or the specified frequency is reached.

If a slide rate is not  specified (xxxxyyyy is zero) then the  last slide
rate used on the channel is used again.


-----------------------------------------------------------------------
4: Vibrato
-----------------------------------------------------------------------
Vibrato means to "oscillate the sample pitch using a  particular waveform
with amplitude yyyy notes, such that (xxxx * speed)/64  full oscillations
occur in the line".  The waveform to use in vibrating is set using effect
E4 (see  below). By  placing vibrato  effects on  consecutive lines,  the
vibrato effect can be sustained for  any length of time.  If  either xxxx
or yyyy are 0,  then values from  the most recent  prior vibrato will  be
used.


_______________________________________________________________________
                                                                      15



MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
________________________________________________________________________

An example is: Note C-3, with xxxx=8 and yyyy=1 when speed=6.   This will
play tones  around  C-3,  vibrating through  D-3  and  B-2 to  C-3  again
(amplitude - yyyy - is 1), with (8*6)/64 = 3/4 of a  full oscillation per
line.  Please see effect E4 for the waveform to use for vibrating.


-----------------------------------------------------------------------
5: Continue effect 3:'Slide to note', but also do Volume slide
-----------------------------------------------------------------------
This effect will change the volume  of a channel while a  tone portamento
(effect 3) is taking place.  The values xxxx or yyyy specify the speed of
the volume change.   If xxxx is nonzero  the volume is increased,  and if
yyyy is nonzero the volume is decreased.  It is illegal for both xxxx and
yyyy to be non-zero.  You cannot slide past 64 or below 0.

As an example, take  the xxxx to  be set to  3.  This  means that at  the
beginning of the line, the current volume of the channel is  increased by
3.  The volume  is increased again for  every tick on  this line and  the
lines following (until there  is a new effect).   Once again, the  volume
cannot slide up past 64.


-----------------------------------------------------------------------
6: Continue effect 4:'Vibrato', but also do Volume slide
-----------------------------------------------------------------------
This effect will change the volume  of a channel while a  vibrato (effect
4) is taking place.   The values xxxx  or yyyy specify  the speed of  the
volume change.  If xxxx is  nonzero the volume is increased, and  if yyyy
is nonzero the volume is decreased.  It is illegal for both xxxx and yyyy
to be non-zero.  You cannot slide past 64 or below 0.

As an example, take  the yyyy to  be set to  2.  This  means that at  the
beginning of the line, the current volume of the channel is  decreased by
2.  The volume  is decreased again for  every tick on  this line and  the
lines following (until there  is a new effect).   Once again, the  volume
cannot slide down below 0.


-----------------------------------------------------------------------
7: Tremolo
-----------------------------------------------------------------------
Temolo means to "oscillate the sample volume using a  particular waveform
with   amplitude   yyyy*(speed-1),   such   that   (xxxx*speed)/64   full
oscillations occur in the line".  The waveform to use to oscillate is set
using the  effect  E7  (see  below).    By  placing  tremolo  effects  on
consecutive lines, the tremolo effect can be sustained for any  length of
time.  If either  xxxx or yyyy are  0, then values  from the most  recent
prior tremolo will be used.

The usage of this effect is similar to that of effect 4:Vibrato.


-----------------------------------------------------------------------
8: This effect is not used.
-----------------------------------------------------------------------
_______________________________________________________________________
                                                                      16



MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
________________________________________________________________________

-----------------------------------------------------------------------
9: Set sample offset
-----------------------------------------------------------------------
This effect allows you to start a sample from a specified position rather
than the normal beginning position.   Multiply the value xxxxyyyy  by 512
to get  the position  in bytes  from the  beginning of  the sample  where
playback should start.   If no sample is  specified with the effect,  but
one is  currently  playing on  the  channel,  then the  sample  currently
playing is retriggered to offset specified.

An example is instrument 2 being  played at note C-3,  with xxxxyyyy=$23.
This would make playback of the sample start at offset $23*$200  = $4600.
This effect gives a rough range to play the sample from.


-----------------------------------------------------------------------
A: Volume slide
-----------------------------------------------------------------------
This effect  will change  the volume  of all  samples being  played on  a
channel.  The values xxxx or yyyy specify the speed of the volume change.
If xxxx is nonzero  the volume is increased,  and if yyyy is  nonzero the
volume is decreased.   It is illegal for  both xxxx and  yyyy to be  non-
zero.  You cannot slide past 64 or below 0.

As an example, take  the yyyy to  be set to  3.  This  means that at  the
beginning of the line, the current volume of the channel is  decreased by
3.  The volume is decreased  by 3 again for  every tick on this  line and
the lines  following (until  there is  a new  effect).   Once again,  the
volume cannot slide down below 0.


-----------------------------------------------------------------------
B: Position Jump
-----------------------------------------------------------------------
This effect xxxxyyyy parameter specifies a position in the  pattern table
that playback should jump  to after this line.   Legal values are  in the
range of the number of patters that  are supposed to be in the  song (see
section 2.3).  Values outside this range should be ignored.


-----------------------------------------------------------------------
C: Set volume
-----------------------------------------------------------------------
Effect C will set the volume on a channel to the setting specified by the
xxxxyyyy value.  Legal volumes are in the  range of 0 to 64.   An attempt
to set the volume to a higher value than 64 will just set it to 64.

I don't think we really need an example for this effect.







_______________________________________________________________________
                                                                      17



MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
________________________________________________________________________

-----------------------------------------------------------------------
D: Pattern Break
-----------------------------------------------------------------------
This effect is equivalent to a  position jump to the next pattern  in the
pattern table, with the arguments xxxx*10+yyyy specifying the line within
that pattern to start playing at.  Note that this is NOT xxxx*16+yyyy.

For example, the effect with  arguments xxxx=0, yyyy=0 would  simply jump
to the first line in the next pattern in the pattern table  after playing
the current line.   With arguments  xxxx=1 and yyyy=6  would jump to  the
16th line of  the next  pattern in the  pattern table  after playing  the
current line.


-----------------------------------------------------------------------
E0: Set filter on/off
-----------------------------------------------------------------------
This sets a hardware sound filter to ON (if yyyy is 0) or OFF (if xxxx is
nonzero).  If your sound device  has built-in filters, you  should ignore
this effect command.  This effect is primarily used on Amiga 500 and 2000
computers to dick around with the hardware filter.


-----------------------------------------------------------------------
E1: Fineslide up
-----------------------------------------------------------------------
This effect functions just  like effect 1, except  that the frequency  of
the sample is only modified once.   At the beginning of a  line, whatever
frequency is being  played on  a channel  is incremented  by yyyy  notes.
This effect does NOT continue on  the lines following.  You  cannot slide
the frequency above the  note B-3 (unless you  implement octave 4 :  NON-
STANDARD!).

An example here would be effect  E, xxxx=1 (the extended  effect number),
yyyy=3.  This  would slide the  current frequency up  three notes at  the
beginning of the line.


-----------------------------------------------------------------------
E2: Fineslide down
-----------------------------------------------------------------------
This effect functions just  like effect 2, except  that the frequency  of
the sample is only modified once.   At the beginning of a  line, whatever
frequency is being  played on  a channel  is decremented  by yyyy  notes.
This effect does NOT continue on  the lines following.  You  cannot slide
the frequency below the  note C-1 (unless you  implement octave 0 :  NON-
STANDARD!).

An example here would be effect  E, xxxx=1 (the extended  effect number),
yyyy=2.  This  would slide the  current frequency down  two notes at  the
beginning of the line.




_______________________________________________________________________
                                                                      18



MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
________________________________________________________________________

-----------------------------------------------------------------------
E3: Set glissando on/off
-----------------------------------------------------------------------
The argument yyyy to this  effect specifies whether the  glissando effect
is ON (yyyy  is 1) or  OFF (yyyy is  0).   If glissando  is on, then  the
'Slide to note' will  slide a half note  at a time.   Otherwise, it  will
perform the default smooth slide.


-----------------------------------------------------------------------
E4: Set vibrato waveform
-----------------------------------------------------------------------
This effect means to set the waveform appearance for succeeding 'vibrato'
effects.  There  are currently  four possible appearances  for the  wave,
each with a possible  'retrigger'.  Two cycles  are shown below for  each
type of waveform:
                                             yyyy
    Waveform   Name                Retriggered  No Retrigger
    ---------- ------------------- -----------  ------------
    /\  /\     Sine (default)           0            4
      \/  \/

    |\ |\      Ramp down                1            5
      \| \|

    ,-, ,-,    Square                   2            6
      '-' '-'

    ?????????  Random                   3            7

A "retriggered" waveform will  be reset to  the start of  a cycle at  the
beginning of each new note.   If a wave is selected  "without retrigger",
the  previous  waveform  will  be  continued.    Waveforms   are  usually
retriggered.


-----------------------------------------------------------------------
E5: Set finetune value
-----------------------------------------------------------------------
This effect command sets the finetune value for the current instrument to
the signed nibble value  yyyy.  This value  overrides the value found  in
the sample information block at the  beginning of the MOD file.   The new
finetune remains until changed by another E5 effect.

           Value:  7  6  5  4  3  2  1  0  F  E  D  C  B  A  9  8
 Finetune to set: +7 +6 +5 +4 +3 +2 +1  0 -1 -2 -3 -4 -5 -6 -7 -8

This effect  is implemented  by storing  period values  for all  possible
finetunes, and simply switching to a different table of periods when this
effect is encountered.  See section 3.3 for more information.   Section 4
lists the period tables for finetunes for octaves 1 to 3.




_______________________________________________________________________
                                                                      19



MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
________________________________________________________________________

-----------------------------------------------------------------------
E6: Loop pattern
-----------------------------------------------------------------------
This effect  allows a  section of  a pattern  to be  'looped', or  played
through, a certain number of times in succession.  If the effect argument
yyyy is zero, the effect specifies the loop's start point.  Otherwise, it
specifies the number of times to play this line and the  preceeding lines
from the start point.   If no  start point was  specified in the  current
pattern being played, the  loop start defaults to  the first line in  the
pattern.  Therefore, you cannot loop through multiple patterns.

An example:

On line 3,  the effect E6  is encountered, with  yyyy=0.  This  specifies
that line 3 is the beginning of a loop in this pattern.
Down on line 52, the effect  E6 is encountered again, with yyyy=2.   This
means to jump back and play the lines from line 3 to  line 52 again twice
more before continuing with the rest of the pattern.


-----------------------------------------------------------------------
E7: Set tremolo waveform
-----------------------------------------------------------------------
Line command  E4,  this  sets  the  waveform  appearance  for  succeeding
'tremolo'  (volume)  effects.     There   are  currently  four   possible
appearances for the wave, each with  a possible 'retrigger'.   Two cycles
are shown below for each type of waveform:
                                             yyyy
    Waveform   Name                Retriggered  No Retrigger
    ---------- ------------------- -----------  ------------
    /\  /\     Sine (default)           0            4
      \/  \/

    |\ |\      Ramp down                1            5
      \| \|

    ,-, ,-,    Square                   2            6
      '-' '-'

    ?????????  Random                   3            7

A "retriggered" waveform will  be reset to  the start of  a cycle at  the
beginning of each new note.   If a wave is selected  "without retrigger",
the  previous  waveform  will  be  continued.    Waveforms   are  usually
retriggered.


-----------------------------------------------------------------------
E8: This effect is not used.
-----------------------------------------------------------------------





_______________________________________________________________________
                                                                      20



MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
________________________________________________________________________

-----------------------------------------------------------------------
E9: Retrigger sample
-----------------------------------------------------------------------
Effect E9 allows  you to re-trigger  a specified  sample at a  particular
note after yyyy  ticks during the  line.   For example,  say note C-3  is
specified, with yyyy=2 when  the speed is currently  6.  This would  mean
that at the beginning  of the line the  specified sample is started,  and
after two ticks it is restarted.   This continues until the  beginning of
the next line.  This effect is used mostly with samples of hi-hats.


-----------------------------------------------------------------------
EA: Fine volume slide up
-----------------------------------------------------------------------
This effect increments  the volume of  a particular  channel once at  the
beginning of the line  by yyyy points.   There is no continuation  of the
slide on successive  lines or for  other notes.   You cannot slide  above
volume 64.


-----------------------------------------------------------------------
EB: Fine volume slide down
-----------------------------------------------------------------------
This effect is  just like  effect EA,  except the  volume is  decremented
rather than incremented by the value  yyyy.  There is no  continuation of
the slide on successive lines or for other notes.  You cannot slide below
volume 0.


-----------------------------------------------------------------------
EC: Cut sample
-----------------------------------------------------------------------
This effect sets the  volume of the  sample which is  playing to 0  after
yyyy ticks in the current line.  This has the effect of stopping a sample
abruptly.  An example here  is to play the  note C-2, with effect  EC and
argument yyyy=3, when the speed is 6.  The sample is started  at note C-2
at the beginning of the line, and after the third tick of 6 in that line,
the volume on the  channel is set to  0 (cutting it off).   Note that  if
yyyy is 0, nothing will be heard.


-----------------------------------------------------------------------
ED: Delay sample
-----------------------------------------------------------------------
This effect delays the start of  a sample until tick yyyy in  the current
line.  For example,  if note C-2 is  played, with effect ED  and argument
yyyy=3 when the speed is 6.   The note C-2  will be triggered at  the 3rd
tick after the start of the line.  The purpose of this effect is to delay
the start of a sample for a VERY short amount of time.






_______________________________________________________________________
                                                                      21



MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
________________________________________________________________________

-----------------------------------------------------------------------
EE: Delay pattern
-----------------------------------------------------------------------
This effect  forces a  small delay  in a  pattern  in between  successive
lines.  All notes and effects  continue during this delay.   The argument
yyyy specified the number of  line-equivalent time slices to  wait before
resuming playback.  For example, if  effect EE is encountered  with speed
being 6 and argument yyyy=4, then the next line will be delayed  24 ticks
before it is executed.


-----------------------------------------------------------------------
EF: Invert loop
-----------------------------------------------------------------------
This effect is used on the Amiga to play samples backward at  a specified
speed.  It is not really  feasible to implement on  other architechtures,
and it is not used that often.


-----------------------------------------------------------------------
F: Set speed
-----------------------------------------------------------------------
This effect changes the  speed of playback so  that xxxxyyyy ticks  occur
during every line, starting on the NEXT line.  The initial  speed (before
any 'set speed' effects are encountered) should be set to 6.   A value of
xxxxyyyy=0 should technically cause playback  to stop, but this  value is
commonly ignored as garbage.

Valid values for speed setting in this manner are 1 to 31.  If a value is
read that is above 31,  it means to set  a modified speed based  on beats
per minute, where 4 lines are  1 beat.  This means  that if I try  to set
the speed to 42, I am  specifying 42 beats per minute, or  42*4=168 lines
per minute.    You then  have  to  figure out  how  long  to spend  on  a
particular line.

If multiple set speed  effects are performed on  a single line, then  the
effects on the higher-numbered channels have precedence over  the effects
on the lower-numbered channels.

This effect has the largest  number of implementations and  is particular
to the number of effects that a particular file player supports.



3.5 Other information
_______________________________

If you're  sound  device  is able  to  provide  stereo output  (like  the
UltraSound), then you  need to  know what  the balance  for each  channel
should be.  Channels 1 and 4 are left, and 2 and 3 are right.

If you are programming  for the UltraSound, it  is best not to  shove the
balances all the way over to the left or to the right.  Try  a value of 2
for channels 1 and  4 and a value  of 13 for  channels 2 and  3.  If  you
don't like it - change it.
_______________________________________________________________________
                                                                      22



MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
________________________________________________________________________

4.0 Period and Volume tables
_______________________________

Here are the period tables for the different fine-tune values:

856,808,762,720,678,640,604,570,538,508,480,453 : C-1 to B-1 Finetune 0
428,404,381,360,339,320,302,285,269,254,240,226 : C-2 to B-2 Finetune 0
214,202,190,180,170,160,151,143,135,127,120,113 : C-3 to B-3 Finetune 0

850,802,757,715,674,637,601,567,535,505,477,450 : C-1 to B-1 Finetune +1
425,401,379,357,337,318,300,284,268,253,239,225 : C-2 to B-2 Finetune +1
213,201,189,179,169,159,150,142,134,126,119,113 : C-3 to B-3 Finetune +1

844,796,752,709,670,632,597,563,532,502,474,447 : C-1 to B-1 Finetune +2
422,398,376,355,335,316,298,282,266,251,237,224 : C-2 to B-2 Finetune +2
211,199,188,177,167,158,149,141,133,125,118,112 : C-3 to B-3 Finetune +2

838,791,746,704,665,628,592,559,528,498,470,444 : C-1 to B-1 Finetune +3
419,395,373,352,332,314,296,280,264,249,235,222 : C-2 to B-2 Finetune +3
209,198,187,176,166,157,148,140,132,125,118,111 : C-3 to B-3 Finetune +3

832,785,741,699,660,623,588,555,524,495,467,441 : C-1 to B-1 Finetune +4
416,392,370,350,330,312,294,278,262,247,233,220 : C-2 to B-2 Finetune +4
208,196,185,175,165,156,147,139,131,124,117,110 : C-3 to B-3 Finetune +4

826,779,736,694,655,619,584,551,520,491,463,437 : C-1 to B-1 Finetune +5
413,390,368,347,328,309,292,276,260,245,232,219 : C-2 to B-2 Finetune +5
206,195,184,174,164,155,146,138,130,123,116,109 : C-3 to B-3 Finetune +5

820,774,730,689,651,614,580,547,516,487,460,434 : C-1 to B-1 Finetune +6
410,387,365,345,325,307,290,274,258,244,230,217 : C-2 to B-2 Finetune +6
205,193,183,172,163,154,145,137,129,122,115,109 : C-3 to B-3 Finetune +6

814,768,725,684,646,610,575,543,513,484,457,431 : C-1 to B-1 Finetune +7
407,384,363,342,323,305,288,272,256,242,228,216 : C-2 to B-2 Finetune +7
204,192,181,171,161,152,144,136,128,121,114,108 : C-3 to B-3 Finetune +7

907,856,808,762,720,678,640,604,570,538,504,480 : C-1 to B-1 Finetune -8
453,428,404,381,360,339,320,302,285,269,254,240 : C-2 to B-2 Finetune -8
226,214,202,190,180,170,160,151,143,135,127,120 : C-3 to B-3 Finetune -8

900,850,802,757,715,675,636,601,567,535,505,477 : C-1 to B-1 Finetune -7
450,425,401,379,357,337,318,300,284,268,253,238 : C-2 to B-2 Finetune -7
225,212,200,189,179,169,159,150,142,134,126,119 : C-3 to B-3 Finetune -7

894,844,796,752,709,670,632,597,563,532,502,474 : C-1 to B-1 Finetune -6
447,422,398,376,355,335,316,298,282,266,251,237 : C-2 to B-2 Finetune -6
223,211,199,188,177,167,158,149,141,133,125,118 : C-3 to B-3 Finetune -6

887,838,791,746,704,665,628,592,559,528,498,470 : C-1 to B-1 Finetune -5
444,419,395,373,352,332,314,296,280,264,249,235 : C-2 to B-2 Finetune -5
222,209,198,187,176,166,157,148,140,132,125,118 : C-3 to B-3 Finetune -5

...continues on next page...

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MODFIL10.TXT                                      THUNDER (kurtt@sfu.ca)
________________________________________________________________________

881,832,785,741,699,660,623,588,555,524,494,467 : C-1 to B-1 Finetune -4
441,416,392,370,350,330,312,294,278,262,247,233 : C-2 to B-2 Finetune -4
220,208,196,185,175,165,156,147,139,131,123,117 : C-3 to B-3 Finetune -4

875,826,779,736,694,655,619,584,551,520,491,463 : C-1 to B-1 Finetune -3
437,413,390,368,347,338,309,292,276,260,245,232 : C-2 to B-2 Finetune -3
219,206,195,184,174,164,155,146,138,130,123,116 : C-3 to B-3 Finetune -3

868,820,774,730,689,651,614,580,547,516,487,460 : C-1 to B-1 Finetune -2
434,410,387,365,345,325,307,290,274,258,244,230 : C-2 to B-2 Finetune -2
217,205,193,183,172,163,154,145,137,129,122,115 : C-3 to B-3 Finetune -2

862,814,768,725,684,646,610,575,543,513,484,457 : C-1 to B-1 Finetune -1
431,407,384,363,342,323,305,288,272,256,242,228 : C-2 to B-2 Finetune -1
216,203,192,181,171,161,152,144,136,128,121,114 : C-3 to B-3 Finetune -1


The Amiga uses linear volumes from  0 to 64.  The volume  table specified
below lists the logarithmic volume to  use on the UltraSound for  each of
the 65 settings in order to get a linear spread.  If you need volumes for
another sound device, you will have to find them elsewhere.

   0 |    0
   1 | 1750      17 | 2332      33 | 3469      49 | 3528
   2 | 2503      18 | 3240      34 | 3473      50 | 3532
   3 | 2701      19 | 3248      35 | 3478      51 | 3534
   4 | 2741      20 | 3256      36 | 3481      52 | 3538
   5 | 2781      21 | 3263      37 | 3484      53 | 3543
   6 | 2944      22 | 3271      38 | 3489      54 | 3545
   7 | 2964      23 | 3279      39 | 3492      55 | 3549
   8 | 2981      24 | 3287      40 | 3495      56 | 3552
   9 | 3000      25 | 3294      41 | 3499      57 | 3556
  10 | 3017      26 | 3303      42 | 3502      58 | 3558
  11 | 3034      27 | 3310      43 | 3506      59 | 3563
  12 | 3052      28 | 3317      44 | 3509      60 | 3565
  13 | 3070      29 | 3325      45 | 3513      61 | 3570
  14 | 3207      30 | 3458      46 | 3517      62 | 3573
  15 | 3215      31 | 3462      47 | 3520      63 | 3577
  16 | 3224      32 | 3466      48 | 3524      64 | 3580

Happy coding!
    -Thunder













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