Question about EQ chips

[Mark Hammer]

I have some KA2223 5-band equalizer chips. ( https://pl-1.org/getproductfile.axd?productid=970&filename=KA2223.pdf ).  The datasheet shows how to add bands or cascade more than one to achieve 7 and 10-band EQ.

But what if a person only wants to avail themselves of 3 or 4 out of 5 bands?  Given the internal structure of the chip (essentially 5 gyrators that are all-but complete, and merely lack two caps to set resonant frequency, and a control pot), would leaving anything "out" result in noise or any other problems?

[Groovenut]

I'd speculate that as long as the base and NF connections for the unused gyrators were left open (not connected), everything should be fine. I cant see any additional current draw happening that way.

My 2 cents

[R.G.]

Yeah, I think you can just leave the bases and feedback points open. It won't have any more hiss than it would otherwise. 

You could also tie a cap from base to ground to AC-ground the unused transistor base. Probably not necessary, but possible. This might result in a start-up thump as the base caps charged. Maybe a small cap just for hiss. But again, no more hiss than normal results from just not using one or two transistors.