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Re: Gibson reverb tank

8/17/2005 11:26 AM
Peter	Re: Gibson reverb tank Thanks for that. Sure enough, 2500 ohms is wrong, my mistake, it's 1475 ohms--- accutronics 1fb2a1b. It's not the original tank but it does work. 4:1 is the voltage ratio--- I measured it in the circuit with an oscilloscope. So I guess that means the driver sees 1475 ohms times 4 squared = 23600 ohms, which sounds like a reasonable load to drive. The driver circuit is half a 12au7, with a 1k cathode resistor, and a 250 volt plate supply. So it seems like the easiest solution is just to buy another accutronics with the same impedances but longer, since this is a short tank. I'm not set on keeping it all stock, it's a player, not a collector. I notice there's lots of Hammond and Gibbs tanks on ebay, but the meaning of the codes doesn't seem to be readily available like it is for Accutronics. thanks again, Peter

8/17/2005 11:26 AM

Peter

Re: Gibson reverb tank

Thanks for that.

Sure enough, 2500 ohms is wrong, my mistake, it's 1475 ohms---
accutronics 1fb2a1b. It's not the original tank but it does work.

4:1 is the voltage ratio--- I measured it in the circuit with an oscilloscope. So I guess
that means the driver sees 1475 ohms times
4 squared = 23600 ohms,

which sounds like a reasonable load to drive.
The driver circuit is half a 12au7, with a 1k cathode resistor, and a 250 volt plate supply.

So it seems like the easiest solution is just to buy another accutronics with the same impedances but longer, since this is a short tank. I'm not set on keeping it all stock, it's a player, not a collector.

I notice there's lots of Hammond and Gibbs tanks on ebay, but the meaning of the codes doesn't seem to be readily available like it is for Accutronics.

thanks again,

Peter