Here is a demo of my 1959 Gibson GA20T Ranger. The "T" stands for "tremolo". This is the most sought after of the GA-20 designs. This example was built in late 1959 or early 1960, at the beginning of Gibson's tweed era, after the earlier 2-tone versions were discontinued and redesigned.
What made this version special was the circuit, which features 7 tubes in total and has an odd preamp configuration with 4 different tube types:
5Y3GT (rectifier), 2x 6V6GT (power), 12AX7, 6SQ7, 5879, and 12AY7
This thing is a breakup machine! Anything past "1" or "1.5" on either Channel will break up like nobody's business. The tone is really classic, yet unique at the same time.
The speaker is the original Jensen P12R AlNiCo dated 41st week of 1959. This example has been serviced. It's had a cap job and some minor work done on the tremolo circuit, but other than that, it's 100% original, including most of the original RCA tubes (the 12AY7 is a GE).
CLICK HERE to see another example of this model: https://www.youtube.com/watch?v=7ludDMl5sPQ