AudioKit 5 Amplitude Envelope no sound

Question

I'm new here and new with music apps (and programming in general).

I'm trying to build a synth app using AudioKit 5 for my final project. I made an oscillator and tried to add Amplitude Envelope but no sound coming out. (If I put the oscillator in the output - there is a sound.)

I saw this question in the internet several times in different types but without any solution.

Does anyone know what is the problem? And if not - do you have other solution for envelope?

The code:

import AudioKit
import SoundpipeAudioKit
import UIKit

class TryingViewController: UIViewController {
    
    var osc = Oscillator(waveform: Table(.sine), frequency: 440, amplitude: 0.8)
    var engine = AudioEngine()
    
    override func viewDidLoad() {
        super.viewDidLoad()
    }
    
    @IBAction func onBtn(_ sender: UIButton) {
        
        let envelope = AmplitudeEnvelope(osc)
        envelope.attackDuration = 0.1
        envelope.decayDuration = 0.01
        envelope.sustainLevel = 0.5
        envelope.releaseDuration = 0.3
        
        osc.start()
        do {
            try engine.start()
        } catch {
            print(error, "Field")
        }
        engine.output = envelope
        
        envelope.start()
    }
    
    @IBAction func offBtn(_ sender: UIButton) {
        
        osc.stop()
    }
    
}

Edit:

I add this code and it works now, thanks to Aurelius Prochazk!

var isGateOpend = false 
.
.
. 
if isGateOpend{ 
    envelope.closeGate() 
    isGateOpend = false 
   } else { 
    envelope.openGate() 
    isGateOpend = true 
   }

I still have a click, but I will open another question about it if I won't figure it out.

Thanks in advance!

Aurelius Prochazka · Accepted Answer · 2021-06-23T04:06:35.367

2

The AmplitudeEnvelope is a "Gated" Node meaning that it responds to openGate and closeGate which should be used instead of start stop since those are at the node level rather than control level.

edited Jun 23 '21 at 04:06

answered Jun 23 '21 at 04:00

Aurelius Prochazka

4,510
2
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First - thanks! Can you please explain more and give a code example? And you mean like "envelope.open"? I'm really new. – David Jun 23 '21 at 11:02
Ok, I used this code and it is work but I'm still getting a digital noise (tic) when I close it. is it because of the computer or I need to add something? ` var isGateOpend = false . . . if isGateOpend{ envelope.closeGate() isGateOpend = false } else { envelope.openGate() isGateOpend = true } ` – David Jun 23 '21 at 13:08
1

With a release value of 0.3 yo should not hear a click when running envelope.closeGate(). Are you also stopping the oscillator as it looks like you are in offBtn code originally? – Aurelius Prochazka Jun 24 '21 at 17:05
Even with a release value of 0.7 I still have a click, and I don't have oscillator.stop() anymore. Do you have any idea why I still have a click? The attack works good – David Jun 25 '21 at 15:03
1

FWIW I pasted in your code and I don't hear a click on my system. – Aurelius Prochazka Jun 28 '21 at 05:31
Solved, Thanks! When I wrote it correctly with mvc.. – David Jul 19 '21 at 11:11

AudioKit 5 Amplitude Envelope no sound

1 Answers1