5 band tone control

Hi
I have been looking for a 5 band tone control on the internet. I found some circuit diagrams on pinterest. I don't know much about how tone controllers work but I want to DIY one for my amp. Building stuff by myself is fun. I am interested in OP Amp based preamps because getting specific transistor is hard. Here's some circuit diagrams I have found. I am interested in active tone controls(which I don't understand much but seems more interesting). If these circuits are no good please provide me one circuit that is tested and performs great.
Thank you.
 

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You can also look at the schematics/service manuals for audio gear that have the functionality you desire.
I can think of one a fisher rs-2010
Refer to this web site as well
https://sound-au.com/
As for using current production bjts, I would think that ksc1845 and ksa992 should suffice.
There is also the option of a parametric equalizer which can provide more control in some instances.
 
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I don't know much about how tone controllers work but I want to DIY one for my amp.
I would recommend modelling these rather simple circuits in LTSpice and you will get a clear (graphical) overview how the unit behaves when regulator(s) are in limit positions. Also "fooling around" with component values is easy in a computer compared to testing them on breadboard. ;)
 

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Hi
I have been looking for a 5 band tone control on the internet. I found some circuit diagrams on pinterest. I don't know much about how tone controllers work but I want to DIY one for my amp. Building stuff by myself is fun. I am interested in OP Amp based preamps because getting specific transistor is hard. Here's some circuit diagrams I have found. I am interested in active tone controls(which I don't understand much but seems more interesting). If these circuits are no good please provide me one circuit that is tested and performs great.
Thank you.
Don't build these circuits. They are extremely bad.
 
Oh wow! That looks really interesting and easy to build. Thank you so much. I will look into it.

It's a much better design than any of the designs you posted. If you must have a multiband equalizer, that's a good one and should be easy to build.

It's not shown, but the usual chip bypassing precautions are mandatory. Design engineers typically assume you know this so if you don't then look it up.
 
Regarding the initial idea to have 5-band equalizer - the frequency response will be quite "bumpy".
If that is not a problem, then it will be fun to play and learn with.

Something like this - only the central 1kHz band notch is missing - the band was defective when taking measurements.
 

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music soothes the savage beast
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Hi
I have been looking for a 5 band tone control on the internet. I found some circuit diagrams on pinterest. I don't know much about how tone controllers work but I want to DIY one for my amp. Building stuff by myself is fun. I am interested in OP Amp based preamps because getting specific transistor is hard. Here's some circuit diagrams I have found. I am interested in active tone controls(which I don't understand much but seems more interesting). If these circuits are no good please provide me one circuit that is tested and performs great.
Thank you.
I built this one long time ago. Worked fine.
https://www.diyaudio.com/community/...-good-5-band-tone-control.380988/post-6888925
 
Well I just glanced at one of the circuits and it was designed with an input impedance of 2.2 K. I look no further because that is so very, very wrong.
At least you have provided reasosn why not to use some of the circuits rarher than come out with unhelpful Smart Alec remarks like "trust me".

2.2k input impedance need not be a problem if the preceding stage had a low output impedance, which most op amp stages have.