Possible bug in add_synth?

[dayunbao]

I'm trying to use Note Off messages to trigger the gate on the envelope of a synth. This seems to be the only way to get close to something like a hardware synth where so long as you're pressing the key, the note keeps playing. I'm having a couple of issues with it, though. I'll create separate discussions for each issue. Below is the relevant code:

@synthdef()
def multi_osc(
    frequency=440.0, 
    pulse_width=0.5, 
    amplitude=0.5, 
    add=0.0, 
    pan=0.0, 
    out_bus=0, 
    osc_type=0.0, 
    attack=0.01, 
    decay=0.3,
    sustain=0.5,
    release=1,
    gate=1,
):
    oscillators  = [
        SinOsc.ar(frequency=frequency),
        LFTri.ar(frequency=frequency),
        LFSaw.ar(frequency=frequency),
        LFPulse.ar(frequency=frequency, width=pulse_width),
        WhiteNoise.ar(),
    ]
    signal = Select.ar(sources=oscillators, selector=osc_type)
    signal *= amplitude
    signal += add
    signal = Pan2.ar(source=signal, position=pan)
    env=Linen.kr(gate=gate,attack_time=attack, sustain_level=sustain, release_time=release, done_action=2)
    signal *= env
    Out.ar(bus=out_bus, source=signal)

def init_synth(self, frequency: float) -> Synth:
        note_on_synth = self.synth_group.add_synth(multi_osc)
        note_on_synth.set(
            frequency=frequency,
            pulse_width=self.pulse_width, 
            amplitude=self.amplitude, 
            add=self.add, 
            pan=self.pan, 
            out_bus=self.out_bus, 
            osc_type=self.osc_type, 
            attack=0.01, 
            decay=0.3,
            sustain=0.5,
            release=1,
            gate=self.gate)
        
        return note_on_synth

def on_note_on(self, note_on_msg: mido.Message) -> None:
        """
        Create a synth to play each note when the button is pressed on the sequencer.
        This treats the sequencer as a keyboard.
        """
        scaled_midi_note = note_on_msg.note + ((12 * self.octave) + 2)
        converted_midi_note = midi_note_number_to_frequency(scaled_midi_note)
        synth = self.init_synth(frequency=converted_midi_note)
        self.playing_synths[note_on_msg.note] = synth

    def on_note_off(self, note_off_msg: mido.Message) -> None:
        self.playing_synths[note_off_msg.note].set(gate=0)
        del self.playing_synths[note_off_msg.note]

In this discussion I want to talk about add_synth. I initially set it up like this:

def init_synth(self, frequency: float) -> Synth:
        return self.synth_group.add_synth(
        multi_osc,
        frequency=frequency,
        pulse_width=self.pulse_width, 
        amplitude=self.amplitude, 
        add=self.add, 
        pan=self.pan, 
        out_bus=self.out_bus, 
        osc_type=self.osc_type, 
        attack=0.01, 
        decay=0.3,
        sustain=0.5,
        release=1,
        gate=self.gate
)      

However, only the value of frequency was successfully reaching the synth. In order to get things to work properly, I had to do it like in the first code block (call add_synth on the group, and then call set on the synth. Is this a bug, or did I do something wrong?

[josephine-wolf-oberholtzer]

What does reach mean here? Can you dump out the actual OSC messages sent via the with server.osc_protocol.capture() as transcript technique I showed you previously? Again, I can't run your code (it's not a minimal working example) and I don't have any debugging information to work off of.

[dayunbao]

The way I detected a problem is that I have an effect module, and when it's connected, I use a bus to route the audio signal from the synth/SynthDef to the effects synth. When I have the init_synth method set up this way:

def init_synth(self, frequency: float) -> Synth:
    return self.synth_group.add_synth(
        multi_osc,
        frequency=frequency,
        pulse_width=self.pulse_width, 
        amplitude=self.amplitude, 
        add=self.add, 
        pan=self.pan, 
        out_bus=self.out_bus, 
        osc_type=self.osc_type, 
        attack=0.01, 
        decay=0.3,
        sustain=0.1,
        release=0.01,
        gate=self.gate)

this is what I get :

...
logging.getLogger("supriya.osc").setLevel(logging.DEBUG)
...

DEBUG:supriya.osc.out:[127.0.0.1:57110/0x7e62244775d0] OscMessage('/s_new', 'multi_osc', 1017, 0, 1001, 'frequency', 277.1826309768721, 'out_bus', 'a18', 'release', 0.01, 'sustain', 0.1)

synth = self.init_synth(frequency=converted_midi_note)
logger.info(synth.get("out_bus"))

INFO:components.multi_oscillator:{'out_bus': 0.0}

So you can see that even though the OSC message is correctly setting the bus, when I query the out_bus parameter of the returned synth, it shows that audio is still going to the default out. I also can't hear the reverb the effects synth should be providing. Is that enough info, or do you need more?

[josephine-wolf-oberholtzer]

out_bus', 'a18' indicated mapping the out_bus parameter to a bus, not using the index of that bus. Wrap self.out_bus in int(self.out_bus).

[dayunbao]

out_bus', 'a18' indicated mapping the out_bus parameter to a bus, not using the index of that bus. Wrap self.out_bus in int(self.out_bus).

Oh, damn. I was wondering what the a at the beginning meant. OK, so this is different from SuperCollider where you can pass an int or a Bus object interchangeably. Awesome. Thanks again!

[josephine-wolf-oberholtzer]

Honestly, I could have sworn that it would coerce the Bus object to an int, but I guess I landed the other way. Not sure what's best, given how few people use this. I don't look at sclang as a guide really, so not sure.

You can always explicitly ask for mapping via my_bus.map_symbol() or explicitly an index via int(my_bus).

[dayunbao]

Before I started working on the sequencer, and was just playing a pattern immediately after instantiating a DualOscillator object, everything worked perfectly. When the effects module was connected, I heard the reverb while the pattern played. I didn't look into the underlying code to know why it's behaving differently, tho.

…

On Fri, Jan 24, 2025, 7:25 PM Joséphine Wolf Oberholtzer < ***@***.***> wrote: Honestly, I could have sworn that it would coerce the Bus object to an int, but I guess I landed the other way. Not sure what's best, given how few people use this. I don't look at sclang as a guide really, so not sure. You can always explicitly ask for mapping via my_bus.map_symbol() or explicitly an index via int(my_bus). — Reply to this email directly, view it on GitHub <#418 (reply in thread)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ACVNNESXZB3VSLEAPJF3W3L2MKASJAVCNFSM6AAAAABVZYNXJGVHI2DSMVQWIX3LMV43URDJONRXK43TNFXW4Q3PNVWWK3TUHMYTCOJUGYZTQNQ> . You are receiving this because you authored the thread.Message ID: ***@***.*** com>