The methodology is from http://www.geofex.com/Article_Folders/xformer_des/xformer.htm
Winding a OT for a Vox AC30.
Power = 30W
Primary Impedance : 3700 Ohm / 4kOhm (depending on the source you use. I went with 3700)
Secondary Impedances : 4/8/16 Ohm
Lowest Frequency= 70Hz
Highest Frequency=...
