What kind of component are these?

[dragonbat13]

[/img][/img]g]The square things above the tube sockets.

I want to modify a set from an organ and will keep the umbilical between the two. I also have all the Baldwin tubes and the Jensen c12 q speakers. I pulled the rotating speaker equipment. It's gonna be a neat build.

But I am wondering about those square things. The holes if removed could be used for localized filtering.

I was just unfamiliar with the cube things. Adjustable capacitor?

Some kind of coil?

Btw, check out how nice that work is. I want to keep it as original as possible for now.

[TUBEDUDE]

They're tunable coils. Found primarily in radio circuits. Does it have a make or model number?

[dragonbat13]

The organ is an L74 with dated 1965 speakers. Baldwin organ but no model on the actual amps.

[TUBEDUDE]

Tuning circuit for the bass pedals maybe?