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Supro Rhythm King Notes

Model

The Rhythm King was offered around 1958 and 1959. This one is a 1958 model. All indications point to the Rhythm King as having the designation 1622B, which was a 1622T without trem.

There is one being demo'ed by a guitarshop on youtube. The controls are VOL+VOL+TONE (no treb). There was another one on youtube that had black fill plugs where the trem controls normally would be on a 1622T (where that was original Supro or not, who knows...).

Schematic

See the Rhythm King schematic page.

Speakers

This came with two 6x10 Rola speakers

caps

Its looks like most of those Valcos use a 20/10/10 450V. (6161,6424)

CE 20/10/10/10

Voltages

Ken Watts at turretboards.com sells a S6424 kit, which is based on Supro's 6973 S6424 amp. Ken's schematic indicates 350V B+ on 6973 plates, and 23v on the cathodes with a 250ohm-R (250/23=.9, 45ma ea. tube?).

Filament Draw.

2 12AX7's: 300ma + 300ma, 2 6973's: 450ma + 450ma, (=1.05A)

Power Transformers

The Classic-Tone 40-18062 ($68) is a 305-0-305 (6.3@1.75,5@2) replacement for valco PTs #3693, which were used in Valco 22, 510-24, 510-121, 510-149, 6161, 6400, S6422TR, S6622, and S6424.

Output Transformers

See this

If the OT is bad, the Classic-Tone 40-18063 is a 7.5KCT:8ohm OT for Valcos, however the Rhythm King original OT is a 7.4KCT:2ohm transformer.

Pics of the cabinet

 
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