Parametric Mid EQ Pot Wiring

[teleman]

I am rather confused with wiring the mid freq stereo pot in this EQ. The circuit below shows that the these 2 pots,R10A & R10B (actually 1 stereo pot) are wired back to back? So would this be the correct way to wire this?


R10A
Pin 1 to IC1B pin5

Pin 2 to common

Pin 3 to C5


R10B

Pin 1 to R13

Pin 2 common

Pin 3 IC 1B pin 5


The circuit:
http://users.otenet.gr/~athsam/parametric_mid_eq.htm


Thanks

 

[teleman]

Compliments of the season to you all!

I've now wired the pots correctly, but there is a constant hum! I then stumbled upon this link, where a blogger has indicated that the MID pot R11 is wired wrongly!

Here is the link;
Middle Frequency Equalizer with Parametric Feature | EEWeb Community

I quote;
"It would appear that it is either incorrectly designed, or more likely incorrectly drawn / reproduced. The circuit as shown can only produce a cut across the frequency rages as the pot controlling the gain is connected to ground. By breaking the ground connection of R11, and reconnecting it to the output of the Op Amp (IC1B Pin 7). Everything works as described. Hope this helps. I do have screen shots of the responses of the circuit as posted and of the responses and modified circuit if anyone wants them. There are one or 2 different values in my circuit due to the range modifications I required" end quote.

I also notice that, although R4 & R8/R9 values are given seperately, the values of all 3 res are still the same!

The originally published circuit is here;
http://users.otenet.gr/~athsam/parametric_mid_eq.htm

Can anyone tell me what's wrong or throw some light on this please?