[sdiy] super simple portamento / slide / glide / slew limiting circuit?

[Scott Nordlund]

> Trying to mod my Roland CMU-810 synth expander module for portamento / slide / glide / slew limiting over the CV input.
> [and maybe audio in]
> 
> Anyone done this, or can suggest a proper portamento circuit that could be used to add to the input ..
> 
> The electro-music post suggests it'd be as simple as 3 components: a pot, a cap, and an op-amp... 
> http://electro-music.com/forum/post-149264.html
An RC circuit will give you an exponential portamento (constant time). It's possibly more of a "classic" sound, but it might be a little wonky sounding for longer portamento times, since it slows down and asymptotically approaches the destination pitch. A proper slew limiter (constant rate) might be better for general purpose use.