Retro-King Amps announces the 50 Watt Combo

The 50 Watt Combo is a replica of the 1960's 50 watt plexi with a solid state rectifier (you can order this with a GZ34 rectifier tube * if you want) in a combo version.

It uses two EL-34 output tubes and a heyboer 50 watt plexi output transformer. The output tranny built for me by heyboer has the correct 3.4k primary plate load. Unlike the 45, which uses a shared cathode, the 50 watt uses a separate cathode arrangement on the first tube, which adds pre-amp gain. A .68 bypass cap on the second stage 33k slope resistor and 500pf cap gives that classic British midrange crunch of the original. You can order this amp with a small switch that takes this .68 bypass cap in and out of the circuit. I also offer my gain stage mod, which gives you a great amount of controllable gain. Also available is the optional negative feedback control that will give you more or less power amp gain. Also available in a Head Version.


– 2 channel 4 inputs (high & low)

– 2 channel 4 inputs (high & low)

– High treble & normal channels

– 2 Volume, Treble, Mid, Bass and presence

– 2 Matched Svetlana EL34 power tubesv
– 3 JJ 12AX7 preamp tubes

– 1 Solid state rectifier (GZ34 tube by request)

– Heyboer transformers (120/240 volt primary)

– Output Tranny has correct 3.4 k primary

– 4, 8 or 16 ohm selector

– Two speaker outputs

– Plexi panels

– Original 50 watt Plexi specs

– Dijon “mustard” caps allen bradley carbon comp resistors

– Aluminum chassis

– Hand wired point to point (Teflon wire)

– Baltic birch cabinet (black Levant Tolex)

For more information, please visit

This is a Press Release

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