Bug with AMP Module gain control.
I assumed this one must of been a known...
But since the glitch is still present after the last update. I thought I better post about it.
Issue....
When adjusting the the knob of the AMP module manually, the gain "erratically jumps around" higher and lower levels when transitioning through the + 8db to +12db range. The Graphic shaper can be used as sort of a cv volt meter for diagnostic confirmation of the issue.
Additionally, adding a modulation knob to the AMP module eliminates this behavior when making manual adjustments. However, it appears controlling the amp gain by connecting a variable cv source, results in the maximum gain becoming limited to +8db, and not +12db.
Tested on two different model iPads, same result on each.
Hope this helps.
Otherwise I'm having a blast experimenting with synth design...And Looking forward to additional modules for building synths and doing sound design experiments.
Comments
@Horsetrainer No its not a known issue. I wonder how it might happen. Testing here and can't reproduce this, output is smooth and never observed this. Im sending a constant signal to amp and move Amp knob. Whats your Latency setting?
Below screenshot is from my 2017 iPAD / iOS 13.5.... (Note: I get identical behavior on my 2018 iPAD / iOS 13.4.1)
Latency is set to 512 Samples.... (Note: I get identical behavior with Latency set at 128, 256, 512, and 1024)
I use the AMP module often for synth design experiments. The issue manifests as audio crackle/pop when adjusting the AMP above +7db.
Maybe someone else with a standard model 2017 or 2018 iPAD can test this on their unit?
In this screen shot I am simply slowly increasing the AMP level control using my finger.
As I said in my first post. Modulating the AMP Knob using CV (like an LFO) causes no erratic level issues...But (from my measurements), the AMP won't boost the signal above (approx.) +7db using CV modulation.
Edited to Add. Input level into the AMP has no influence on erratic behavior. If I set the KNOB Module to output @ 0.20, I get the exact same behavior adjusting the AMP above +7db (Issue occurs even when AMP level indicator remains in the green).
Ok I got this! It happens when amp goes red. Digging and fixing. Thank you!
Your welcome.
In case you missed the edit to my last post. Here is another screenshot of the same behavior occurring while the AMP is operating in the green.
Thank you for making this amazing App!
Yes, I can reproduce this but it only happens way beyond the clipping threshold. I thought that was normal.
Some crazy waveforms crop up with those crackles at very low frequencies.
Signal type has nothing to do with signal channels, so it must be something else. Could you tell me more or post an example?
@Horsetrainer Ok.. amp signal was clipped to a wrong range, but only when amp was changing :). This will be fixed in upcoming update, but you will need to instantiate amp module again (remove and add) for your old projects. Project keep module versions, to preserve compatibility, even when module behaves wrong (people make use of this :)
@giku Thank you Sir ! :)
sounds much better now
now I need to replace the amps in all projects 😩
No, because you haven't noticed this, or whats worse you could have make use of this :)