@node "Convert"

                Converting between old channel modes and Mix mode

There is one fundamental change needed to songs composed in other channel
modes: All notes played by samples must be transposed up 2 octaves. This is
because there are two extra low octaves in Mix mode, which means that, for
example, note C-1 in an old channel mode is equivalent to C-3 in Mix mode.
(There is also one extra high octave, so that the highest note available is
B-6.)

OctaMED can automatically transpose samples for you, in two different ways.
Only notes played by samples need to be transposed, not synthsounds, MIDI
instruments or ExtSamples (which are now redundant).

Song Options: Changing channel mode

To change channel mode, you use the radio button in the Song Options window.
When changing to and from Mix mode, OctaMED can automatically transpose
notes played by samples up or down 2 octaves, as required. To do this, click
the new channel mode while holding down a Shift key.

So clicking 1-64 Ch Mixing while holding Shift transposes all notes played
by samples up 2 octaves. It also rotates the Oct gadget (Main Control) up 2
places, to ease entering notes. Clicking any other channel mode while
holding Shift does the exact opposite: Notes played by samples are
transposed down 2 octaves, and the Oct gadget is rotated down 2 places.

You can set Mix mode, or any other channel mode, to be the mode used when
OctaMED starts up (or when you clear the song). Use the new Default Channel
Mode cycle gadget in the Miscellaneous Options window.

Miscellaneous Options: Use Mixing

To allow old 4 to 8-channel and Tracker songs to use the new Mix mode,
the Miscellaneous Options window contains two new Use Mixing check
boxes. When on, the required 2-octave transposition to notes played by samples takes
place. There's a separate check box for songs saved by OctaMED in the usual
format (MMD), and for songs created by other Trackers.

When using old 5 to 8-channel songs with the new mode, do not try to set
Volume Adjust to 200% to allow for "halved" samples. Halved samples are in
7-bit quality, so it's best to reload the original samples.


Some other notes

1) Internally, OctaMED has three separate parts which control playing,
   called the "players". There's one player for 4-channel mode, another for
   5 to 8-channel modes, and another for Mix mode.

   When you play a note using the keyboard in 4 or 5 to 8-channel modes,
   the player is used briefly to start the note off, but then the note is
   left to play and finish of its own accord. The Mix mode player, however,
   is used throughout the note's playing, from its start to its finish.

   So the Mix mode player is "switched on" when the first note is started.
   But it isn't switched off when the note has finished. Instead, to react
   more quickly to other notes you play, it's kept switched on until you
   click STOP or press the space bar.

   This means that the player is switched on even when no notes are being
   played. On slower Amigas, this may slow down operation, so simply press
   the space bar to switch the player off. It also means that if you change
   anything in the Mixing Settings window, such as Mixing Frequency or
   track panning, you must stop playing and restart it for the changes to
   take effect. (This doesn't include Stereo Separation, Echo Depth, or
   a change from Echo to Cross Echo or vice-versa.)

2) Do remember about "panic stop"! If the computer seems to lock up during
   play, try holding both mouse buttons down for a few seconds.

3) Samples with very short loops increase processor load. Here, "very short"
   means about a third of Mix Buffer Size (i.e. by default, 100 bytes).

4) 5 - 8 channel mode uses a frequency of 15768 Hz in non-HQ (High Quality) mode,
   and 28867 Hz in HQ mode. In fact, you could perfectly reproduce 4-channel
   mode with a mixing frequency of 3.6 MHz! Though 48 kHz with Smoothing on
   is often better in practice.

5) Almost all settings in Mixing Settings, Mix - Track Panning, and
   Mix - Effect are saved with songs. In particular, Mixing Mode and Mixing
   Frequency aren't saved. This is so that, for example, a song created on
   a fast Amiga using a high frequency won't immediately cause a slow Amiga
   to lock up.

   OctaMED uses a special file format for songs using Mix mode: MMD3. This
   is identical to MMD2. The only reason for its existence is so that older
   versions/player programs will not attempt to play Mix mode songs.

6) You can play samples in either type of memory - Chip or Fast - in Mix
   mode. By default, though, samples are loaded into Fast memory; Load
   Samples To Fast Mem in the Instr menu is automatically switched on.
   Samples in Fast memory can be mixed much more quickly (but bear in mind
   that "fast" memory on an A500 is usually Slow RAM, the same speed as Chip
   memory).

   See part 12.4 for more details about samples in different memory types.

7) An option only applying to Mix mode, Swap Amiga Channels (Mix), can be
   found in the Miscellaneous Options window. Sound channels 0 and 3 should
   be played through your left speaker, 1 and 2 through your right. On some
   Amigas, these are internally swapped round! So switch this check box on to
   correct them.

8) Tempo settings in SPD mode are the same as in 4-channel mode.

                        @{" Other Mix Mode Info " link "other" 0}

@endnode