Constant-S equalizer with constant Q?

Does anyone know of a Constant-S passive EQ topology that has constant-Q rather than proportional? I could force a Langevin 251a type circuit to be constant Q by having a separate LC pair for every DB step, but that seems extremely expensive, convoluted and inefficient. There has to be a simpler way to do it. Thank you!

Here's the 251a, which has proportional-Q.
http://gyraf.dk/schematics/Langevin_EQ251A.GIF

I think you first need to define what you mean by constant Q in the context of an EQ where the amplitude of the bell can be altered by a control.

Cheers

Ian

Hello Ian, thanks for replying.

I would like the steps to behave something like these:



Rather than these:

OK. Your top graph is strictly speaking not constant bandwidth. As I am sure you know, BW is defined as the difference between the frequencies at which the response falls by 3dB from the peak. So, by definition, any EQ set for a 3dB boost must have a BW equal to the skirt so the bottom curve of the top graph needs to be much sharper than it is. The bandwidth lines are also not quite in the right place but that is a minor point. I understand now what you mean. I don't know the answer but I will give it some thought.

Cheers

Ian