I've found some schematics for spring reverbs (8 Ohm input impedance) and would like to try a couple of them with Belton 2-spring and 3-spring tanks.
Belton has a 2-spring tank with 8 Ohm input impedance but their 3-spring tank has a 10 Ohm input impedance.
I'm wondering how to go about adjusting one of these circuits to make it work optimally with the 10 Ohm input... unless you think this is close enough.
Here is a link to the Surfy Bear schematic:
https://schematicsonline.com/schematic/surfy-bear-fet-reverb/
Thanks!
Quote from: spacecommandant on February 15, 2023, 01:04:53 PM
I'm wondering how to go about adjusting one of these circuits to make it work optimally with the 10 Ohm input... unless you think this is close enough.
These may help you:
https://sound-au.com/articles/reverb.htm
https://www.amplifiedparts.com/tech-articles/spring-reverb-tanks-explained-and-compared
Thanks, I've read those, and I was considering building the sound-au Project 34 reverb as well which mentions values to adjust to different tanks, but I'm still not sure how the 10 Ohm will sound with the Surfy Bear or how to tweak that circuit to match. Ultimately, I'll just give it a go and see how it sounds I suppose.
The difference between 8 and 10 Ohms is not that big of a deal. If you were going from 8 to, say, 300 Ohms or higher, then you would probably want to be more careful about changes to the circuit.
They are not even different. The impedance rises with frequency. Different models are quoted at different frequencies.
A 150 may be a poor fit for 8, but 10 and 8 are no different.
The 3-springs are 10 ohm, the 2 springs are 8 ohm. The DC resistance is 0.9 ohm. (The rated impedance is AC at 1kHz.)
http://www.electricalfun.com/workbenchfun/reverb_tank.pdf
If the DC resistance is 10 ohm then it doesn't match the accutronics data but it's probably a nominal impedance of 100 ohm.