The Steel Guitar Forum

I need a new reverb tank for my Session 500. The reverb in the 500 is the 4EB2C1B. I have an extra 9EB2C1B tank here. I see there are slightly different spec's for these reverbs:
4EB2C1B: Input Impedance 600 Ohms, Output Impedance 2250 Ohms(2-spring)
9EB2C1B: Input Impedance 800 Ohms, Output Impedance 2,575 Ohms(3-spring)

Are these tanks interchangeable for my Session 500?

Those impedance values are close enough to each other.
I would have used 9EB3C1B for the long delay. But the larger number of springs should help a lot.