- Edited
math-neon wins the prize! It looks like this implementation of expf() only takes about 1.5x CPU time as a single floating point multiply.
I was originally hesitant to use this thinking expf() was going to be computationally expensive and figured it wouldn't make an audible difference, but I was wrong on both counts. It's computationally cheap and makes a very significant difference in the sound.
Once I implemented this I started hearing a sound that really brought to mind the sound of a Dynacomp, only on Bela you don't have to mess around with that bias trimmer.
Of course, my discovery that e-x with math-neon is little more than a multiply, it makes implementation of a traditional feed-forward compressor trivial...although my feedback compressor performs well enough I'm not seeing a need for yet another compressor.
Now this compressor has added features:
Linear feedback gain mode (the original design)
Exponential feedback gain mode ( approximately log-linear transfer function)
Parallel compression (wet/dry mix)
Check it out if you like compressors like I do. I'm a compressor nerd (in case it isn't self-evident).
These can sound really cool on drums and percussion instruments. I have added enough parameterized control it's not only a guitar effect any more.