Fender reverb driver max current?

[GainFreak]

Hi,

I did some search but I couldn't find any specs referring to how much current the stock Fender reverb driver OT can handle.
Any help would be appreciated.

[Chuck H]

I doubt you'll find that info. That OT runs a 6K6 at about 2.? watts. People commonly plug a 6V6 into the socket. I guess it's good for 3 to 5 watts. Do you need to get closer than that?

If you mean the combo amp reverb OT, then that would be smaller. It only had to handle about 1 watt but a more standard power rating for the time when that OT was made is 3 watts. So I'd guess it at 3 watts.

Don't expect much fidelity or efficiency from either. They were used to drive a transducer that shook springs. So I don't think Leo would have gone all out on these.

Chuck

[Bruce / Mission Amps]

Are you talking about a stand alone reverb unit or the one the is built into a blackface or silver Fender combo/head using a single 12AT7?
If the later, around +20Kohms into 8 to 10 ohms and I've been told about 12ma to 15ma.... but just find any Fender schematic that has the cathode voltage on the parallel 12AT7 triodes and divide the V by the R value to determine the current through the little OT.
Then figure about twice that current is probably way safe enough.

[GainFreak]

Are you talking about a stand alone reverb unit or the one the is built into a blackface or silver Fender combo/head using a single 12AT7?

I'm not talking about the stand alone unit but about the stock 022921 type of reverb drive transformer.
I checked some Fender schematics and most of the time the reverb section is a paralleled 12AT7 with 2k2/22uF combo in the common cathode section. The voltages vary between 8 and 11 Volts which means 3.6-5mA of total current for the 12AT7 which most of the time is running at 400-440V.
Some of the schematics show an unbypassed 680 Ohm resistor in the cathode with voltages between 4.4-6V which is like 7-9mA but then anodes are at 300-350V.
I was wondering because 12AT7 is capable of 10mA per plate but at lower voltages. Obviously the situation here is the opposite - less current, more anode voltage.

[Bruce / Mission Amps]

I'm not talking about the stand alone unit but about the stock 022921 type of reverb drive transformer.
I checked some Fender schematics and most of the time the reverb section is a paralleled 12AT7 with 2k2/22uF combo in the common cathode section. The voltages vary between 8 and 11 Volts which means 3.6-5mA of total current for the 12AT7 which most of the time is running at 400-440V.
Some of the schematics show an unbypassed 680 Ohm resistor in the cathode with voltages between 4.4-6V which is like 7-9mA but then anodes are at 300-350V.
I was wondering because 12AT7 is capable of 10mA per plate but at lower voltages. Obviously the situation here is the opposite - less current, more anode voltage.

And the reverb is frequently roaring, squeally/feeding back and or out of control in the ones with the small cathode biasing resistors.

[GainFreak]

Actually I was asking because I would like to use the transformer for a small SE amp using one or both sections of 12AT7.

[Bruce / Mission Amps]

Actually I was asking because I would like to use the transformer for a small SE amp using one or both sections of 12AT7.

OK then that will work fine if you use a reissue reverb OT found in a Fender tube amp with a 12AT7.

[GainFreak]

OK. Thanks for your answers.
I guess I'll have to do some experiments and use my years to find out whether it's going to sound better with one section at full current or both sections with less current.