Reverb Tanks: low impedance

[shaun]

Heyo. I hope all are well.

I have three nice reverb tanks, except for very their impedance readings. They were salvaged from an old Zenith phono and some Hammond organs.

They read around 171ohms input and the same, or close, output - the readings are written on each tank. They're not the readings I would like; in fact, I may never use them, which would be  a waste. I have read a lot online regarding the issue of tank impedance, and it seems unlikely I can use them in a simple fashion.

Does anyone have any suggestions on how I could bring these up to specs more typical for a guitar amp? I doubt that it could be as simple as adding a resistor or two in series, but I'm not sure.

Thanks, as always.

[Latole]

Best is to test them in a amp, you"ll hear how is the reverb.

Wrong impedance will have a result of too much reverb or less or no reverb.

[sluckey]

The 171Ω DCR inputs are actually about 2000Ω impedance. They were most likely used with a cap driven reverb circuit. Look at some Ampeg schematics for examples.

[shaun]

The 171Ω DCR inputs are actually about 2000Ω impedance. They were most likely used with a cap driven reverb circuit. Look at some Ampeg schematics for examples.

Yes, I figured I was reading them sorta wrong by using a simple R test. Interesting info! I will look at Ampegs. Thank you.

[sluckey]

The attached pdf has a lot of good info. On page 4 is a chart that shows a cross reference between measured DCR and actual impedance.

This file has been posted many, many time right here on Hoffman's forum. It's practically all over the internet. All you gotta do is look...

[thetragichero]

maybe I'm hijacking the thread but besides fender tradition, is there any tonal reason for using a transformer into a low impedance tank rather than a high impedance tank with a capacitor-coupled driver? maybe I'm a cheapskate but I'd rather save the 30 bucks and added weight (however negligible it may be) of using a transformer

[PRR]

Efficiency.