How do I figure out output wattage or an amplifier with 2 x 6V6 tubes in a push pull pair cathode bias configuration. Plate Voltage is 386VDC Cathode Voltage is 20.5VDC at the top of the shared 240 ohm cathode resistor meaning 85.75mA is going through the shared cathode resistor.

THX

:How do I figure out output wattage or an amplifier with 2 x 6V6 tubes in a push pull pair cathode bias configuration. Plate Voltage is 386VDC Cathode Voltage is 20.5VDC at the top of the shared 240 ohm cathode resistor meaning 85.75mA is going through the shared cathode resistor.
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:THX

386V is kinda high for 6V6. Are those 6V6GT ?

In any case, current is in the ballpark for such anode voltgae. Expect anything between 12 and 15 watts max. OP transformers also play a role in the max output you will have. Here's data on the 6V6: http://tdsl.duncanamps.com/show.php?des=6V6

Bookmark this website for future use.

Syl

If you want to figure out what kind of wattage your amplifier is capable of, load it with a speaker (preferrably in another room). Connect a volt meter across the output secondary, and a current meter in series with the secondary. This will, of course, give you wattage capabilities of the amplifier with the particular output transformer you choose. Your voltage and current meters must be capable of reading AC currents. Also connect your oscilloscope across the speaker. Feed an undistorted frequency into the amplifier. Turn the amplifier up until the wave looks distorted slightly. I don't know how certain amounts of distortion look, but it should be able to give you an idea as to how many watts your amplifier can put out before it starts to distort at all. The voltage multiplied by the amperage will give you your wattage.

You could use something else in place of the speaker, but it might not load the transformer properly.

Thomas