The 245 was built with special antique parts that I have collected over the years. The meter dates from the 30's as do the binding posts. Bias, hum null and driver bias are set with the 6 small knobs in front and feedback is set with the center knob.
The 245.1 has essentially the same circuit but with and LED to set the bias and the adjustments are on the rear. The center knob is still feedback as this has a great influence over the sound.
