Using the AD844 as an I/V

[triode_al]

I went through my projects and found a perfboard with two "stacks" of AD844. There was also two 2SK170 and a trimpot for each jfet. It's been soo long since I made it, I don't know what schematic it was based on. Please post the schematic if anyone recognizes the stacks of AD844 and the description of the circuit 😅
IIRC it was to be an I/V board.
TIA 🙂

I expect the jFet/trimmer is for a dc feed to the TDA1541, being 2mA.
[I went through my pile a few days ago; similarly had a stacked AD844 I/V ]

 

[canvas]

Years ago I tried 3 or 4 piggybacked, but they got very hot. I don't know why. There is no oscillation or any side effect. They sound good. Just the temperature is a bit too high for me. Eventually, I moved to OPA861 I/V.

 

[triode_al]

The quiescent current depends on the Vb voltage; like 8V supply is what I used as ideal in my build.