I was curious if anyone else has noticed unusual behavior with the filter on their Uno.
I've noticed that, at extreme settings, there is a significant and abrupt volume drop - as if a gate is closing.
Here's how to reproduce this:
1. Set to factory preset #1
2. Open cutoff to 100% (display will show 127)
3. Set the LFO filter amount to 0%
4. Set filter drive to about 50% (say 65)
5. Play and hold a note.
6. Begin to add resonance.
For me - at or just about about 100 on the resonance knob, there's a very abrupt volume drop. This isn't isolated to resonance. You can work backwards. Set the resonance to 100% and slowly open the cutoff. At about 110 on the cutoff, I get the same thing. Filter drive amount seems to affect this as well.
Also, this is very apparent if the LFO is used to sweep the cutoff. If you set the LFO to a very slow sweep and set the filter amount to 100%, close to the end of the cycle, the same abrupt volume drop is present.
Not trying to make this sound like it makes the Uno a horrible synth. Like most people, I would VERY rarely ever use such extreme filter settings. However this surprises me.
I' thinking that this is caused by the high frequencies generated when there's a lot of resonance with such a low cutoff frequency is bumping into some kind of noise gate?
Or perhaps this has to do with some processing that attempts to bump up the bottom end at low frequency cutoff, where low end drop is present on many classic filters. Perhaps at such extreme settings it gets confused.
Or maybe I got an Uno with a bad filter.
I'd love to know if anyone else can replicate this.
Greg
