stereo graphic equallizer for TDA7297

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Hello everyone,
I’m just a beginner with electronics and I’m trying to build a portable stereo speaker system with a three band graphic equalizer. The amp chip is a TDA7297.
I’m struggling to build a stereo graphic equalizer with 3 potentiometers to connect to the TDA7297.
I found many schematics online like this:
http://www.zen22142.zen.co.uk/Circuits/Audio/3bandton.gif
My problem is that all the schematics I found so far seem to be made just for one channel (mono) whereas I have a stereo signal coming from my source, thus I have two separate channels to control.
If I double this circuit diagram for the two channels, i end up having 6 potentiometers (3 for the Left and 3 for the right channel). Instead I want to control Left and right together with just one trimmer and having an EQ section with a total of three potentiometers.
Does anybody have a circuit diagram for a stereo 3 band EQ with JUST 3 trimmers?
Thank you
 
why are we not doubling the circuit for each channel and using dual gang pots for each band, controlling both the channels together?

Hi Sarathssca, actually i've already tried to use a stereo pot but it didn't work that well. That's why i was wondering if there was another way to control two filters at once.
There are a few simple stereo 3 band eq out there on the market but can't find no schematics available. I'll try again with the stereo pots and see if i can make it work while i'm waiting for other possible solutions.
Thanks
 
Hi Sarathssca, actually i've already tried to use a stereo pot but it didn't work that well. That's why i was wondering if there was another way to control two filters at once.
There are a few simple stereo 3 band eq out there on the market but can't find no schematics available. I'll try again with the stereo pots and see if i can make it work while i'm waiting for other possible solutions.
Thanks

What kind of taper was required for the pots in the design and what kind did you use?

Did you drive the circuit with a low impedance source?

The output needs a capacitor to de-couple the DC present on the output.

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Does anybody have a circuit diagram for a stereo 3 band EQ with JUST 3 trimmers?

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You may find some stereo tone control IC's that would work...I am using a bass/treble/volume/balance IC that uses 4 pots to vary the DC into the IC.
 
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