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FM Source

Macros: ModSrc, FMsrcDlg

The default FM modulator is an internal Sine wave, whose frequency and phase you can control. When you click on the FM Source button, it opens a standard Modulation Source dialog that allows you to select Sine (default) or any lower-numbered stream or combination of streams for Stream Modulation.

The number in parentheses next to each Stream option is its overall stream number. This is a single digit (0-6) that can be used to toggle it via hot-key instead of a mouse click. To select Sine, toggle all Streams off.

On Left Stream 0, Sine is the only option. On Stream 1, you also have the option of selecting Stream 0 as the source. Higher-numbered streams allow all lower-numbered streams, plus all combinations. The Right channel streams are all numbered higher than the Left, so any Right stream can use any and all Left streams.

When more than one stream is selected as the source for a particular modulator, the selected streams are summed together to get the overall modulation. In this case, you should insure that the total of the respective stream Levels does not exceed 100%.

When you select one of the other streams as the Source, the FM Mod Freq and FM Phase controls are disabled from the current stream. Instead, you would use the main Freq and Phase on the selected modulator stream. The Deviation/Depth control works normally.

When using Stream Modulation with Multi-Channel Outputs, unlike normal stereo, the modulator stream itself can be used as an output. This can be used to supply a modulation sync signal to an external device.

Macro Notes:

Use the FM. prefix in addition to channel and stream prefixes to specify the modulator for the ModSrc command. The value you supply is a bit map of the streams to be used, where each bit in the value specifies a specific stream. The bit numbers are the same as the overall stream numbers (0-6) shown in parentheses next to each stream in the dialog, as mentioned above.

You can use binary, hexadecimal, or decimal notation. You can specify more than one stream by setting the appropriate bits.

    Sine (default)     b00000000   h00    0
    L.0 Stream  (0)    b00000001   h01    1
    L.1 Stream  (1)    b00000010   h02    2
    L.2 Stream  (2)    b00000100   h04    4
    L.3 Stream  (3)    b00001000   h08    8
    R.0 Stream  (4)    b00010000   h10   16
    R.1 Stream  (5)    b00100000   h20   32
    R.2 Stream  (6)    b01000000   h40   64

For example, L.3.FM.ModSrc=1 will set Left Stream 3 FM modulation to use the output of Left Stream 0 (bit 1) as the modulation source. L.3.FM.ModSrc=b11 will set it to use the sum of Left Stream 0 and Left Stream 1, since b11 (decimal 3) is the sum of bit 0 (decimal 1) and bit 1 (decimal 2).

Note that the chosen modulator must be available for the given stream, or else the macro will set Sine. Sine is always available, but only streams lower than the current stream may be used as modulators.

If the FM dialog is open, FMsrcDlg=1 opens its Modulation Source dialog, FMsrcDlg=0 closes it, and FMsrcDlg=x toggles between open and closed. Note, however, that you do not need to open the Modulation Source dialog to set its controls directly, as above.

See also Stream Modulation, Frequency Modulation, Frequency Modulation Dialog, Waveform Stream Controls


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