It is not clear from your post whether you think your effect is working correctly and you may not like it, or whether something is not quite right and it doesn't sound like the demos you have heard. So first you should make sure you have the right value components installed that are discussed in this response that help shape the tone in the effect. The tone you get out of it may also have a lot to do with the tone you put into it -- whether your guitar is going through other effects first or is going straight into the ADHD. Since it also has a buffered signal bypass built into it, it is probably supposed to be first in line with your guitar plugged into it. If the pedal has the right parts and seems to be working fine, it comes down to whether you want to experiment with some of the parts choices in this design to see if you can make it sound better to your ears.
Look at the ADHD circuit diagram in the build documents to see where the tone control is located. You could change the value of capacitor c8 to change the freq of the tone control, and/or change the value of resistor R14. If you look at audio path in the circuit diagram, you can see that C5 and R9 are also connected in a similar way like the tone control circuit, they are just located earlier in the signal chain in one of the gain stages -- those parts are also affecting the tone that goes through the rest of the circuit, so you could try changing the values to see what sounds better to you. If you want to understand what these parts are doing and what changing the values of one or both of those parts would do, I suggest looking for some articles about the tone control on the big muff pi since some of those have great explanations of the tone circuits and changes that were made over time to the different BMP versions.
