Quote:
How do you decide where the x-formers go with headphones btw?
From
AX84 FAQ
What is the headphone trick?
This is the best way to find the quietest place to put a reverb, output, driver, or any other signal transformer to get the least hum. CAUTION: THIS INVOLVES WORKING ON THE AMP WITH WALL VOLTAGE PRESENT. WALL VOLTAGE CAN BE FATAL.
First set up the power transformer. If it's not installed yet, all the better, but if it is, this will still help. If the PT is not installed, wire up the primaries to a power cord, but do not wire up any secondaries-- tape the ends of the secondaries. If the PT is installed, fine, just make sure there is no circuit on any of the secondary leads (pull all tubes, and disconnect leads and tape them as necessary).
Now set up the signal transformer (output, reverb, whatever). Hook one set of OT secondaries (your choice, but I usually go from ground to the highest impedance tap, don't worry about impedance matching here!) to a set of headphones. Tape the primary leads.
Put the headphones on, plug in the power cord, and start moving the signal transformer around. Try it all over the chassis, and also rotate it. While you might expect the least hum with the transformers as far from each other as possible and at right angles (and that may be the case for you), it might come at an odd angle and/or position. Sometimes the least hum occurs when the transformers are side by side. When you find the quietest spot, use a permanent marker to mark where the mounting holes should be.
If you have more than one signal transformer, repeat this for each one. When you're finished, unplug the PT. That's it!
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from recording, you need to write your book!
Thanks for the kind words Jim. I appreciate it. Glad that all my blabbering is useful. 
