Re: [fluid-dev] Multiple Synthesizers

[David Henningsson]

On 2014-09-29 03:03, Garth Hjelte wrote:
> Can you have different Fluidsynth Synthesizers open at one time?
>
> My issue is this: my app uses Fluidsynth to play SoundFonts created by my app 
> on the fly to the user to play via MIDI. Almost always they are single-Bank 
> single-Preset SoundFonts meant to represent one imported instrument. They are 
> imported in via the massive other instrument file formats (Kontakt, EXS24, 
> GigaStudio, etc.)
>
> However, sometimes the Preset I want to playback is actually a SoundFont Preset.
>
> So, stepping back: I make the on-the-fly SoundFonts on the fly while a user 
> chooses to audition things, and I keep them loaded in Fluidsynth so if the user 
> wants to play it again they can. So I do sfload() and then do 
> set_bank_offset(), so at least I have 128 spots to put Instruments before I 
> wrap around and sfunload() and start having to give up spots.
>
> But, I'm in a real pickle if worst comes to worst and a person wants to listen 
> to a Preset that is part of a SoundFont that has all 128 Banks filled or 
> occupied. (And I know of plenty that are quite small but yet have all spots 
> filled.) I'd have to go super-overkill and sfunload() however-many SoundFonts...
>
> I know there's other ways of doing this, but they seem to all require more 
> file-reading and composing that may not be necessarily necessary.
>
> If I could make another synthesizer, then I'd have more room. Is that doable?

In general, yes. You can certainly make several fluid_synth_t objects 
and they will just work independently of each other. Each one will have 
a separate reverb and chorus engine, e g.

If you want to mix output from several fluid_synth_t into the same audio 
driver, you will have to do this yourself. Use the 
new_fluid_audio_driver2 call, and from that callback, call 
fluid_synth_write_* for all of the synths. (Note that the callback will 
be called from a real-time priority thread.)

// David