voltage clamping

[Kipper4]

So I have this rectifier and i'd like to limit its output somewhere between 3.5 ishV and 4.5ish or a bit less.
Reason being this would be the useful range of voltages needed to control my lfo speed.
As can be seen the zener is doing a pretty good job for the lower end voltages.
But how do I limit/clamp/rectify the upper voltage range I'd like (not sure of the correct terminology).

Thanks

[Fender3D]

Why don't you play with IC3b's Vb and gain?

[diffeq]

As I understand it, you want to cut the voltage exceeding a certain level. In this case, a diode connected to a voltage source, like so:


should do it.
Cut-off voltage = Diode drop (0.6) + threshold pot (0 to 9). Hope this helps. If you want tighter than 0.6V region, use 1N5817.

[anotherjim]

VB for the whole is the minimum CV. Otherwise, the envelope will give you nothing unless it exceeds any minimum CV applied at the end, although that could be a gating effect you want?
I'd avoid adding DC gain to the envelope CV and clamp the max with a *zener across the envelope cap. If the cap can go higher than max - because you clamp it right at the end, then the envelope CV decay will be artificially delayed until the cap voltage falls below the clamp level.
If the Cv range is really only 1V, then any gain should be before the rectifier so you don't need DC amplification of the CV, which will make it difficult to keep within the required limits.

*not limited to standard zener values, combined LED and/or diode series strings might give you closer to limits needed.