RCA Victor began producing radios in 1930 and many of these tube radios were sturdy enough to stand the test of time, surviving to this day. Many RCA Victor radios are finding new life as amps for guitars. To convert your radio to an amp using some of its existing wiring, you’ll need to use an RCA Victor model that has an audio input in the back of the case, such as the R32. Even inputs that originally supported phonographs will work for your amp.
Collect your electric guitar, a direct box with a ground lift switch and a 1/4" output, a 1/4" mono cable, and 1/4" mono-to-stereo cable to get started. A direct box, also called a DI, is used to connect guitars to audio devices such as mix boards and will help control the sound for the RCA Victor amp. Yours needs a ground lift switch in order to prevent sound irregularities from the tube radio, especially buzzing and humming.
For most RCA Victor radios with an audio output, the 1/4" cable size will work, but you should check your model to make sure. The 1/4" size is standard for direct boxes, so electronics, home audio and music retailers often carry cables that are 1/4” on one end and another size on the other end. The cable you get for your amp, however, needs to be a mono-to-stereo cable regardless of size.
Guitar Bone Connects to the Amp Bone
You’ll want to connect the 1/4" cable to both your guitar’s output and the input on the DI. Take the 1/4" mono-to-stereo cable and plug the mono end into the direct box; plug the stereo end into your radio’s audio input. If your DI supports mono and stereo modes, make sure the output is set to a stereo option. Using stereo provides better-quality sound in a signal that the radio won’t distort.
Step Away From the Amp
After you’ve plugged everything in, move your guitar at least three feet from your amp. Turn the volume down to zero or off on each device. Now plug in your amp to a power outlet and turn its volume to one of the lowest settings. Test the amp by playing your guitar as you slowly turn up its volume. You’re listening both for quality and noise. Use your ground lift switch to help cancel any buzzing or humming.
Tips, Tricks and Sounds
If you experience humming and buzzing from your amp despite the DI’s best efforts, try moving farther away from the amp. You can also turn down the volume on your guitar and slowly turn up the volume on the radio, but you don’t want to move past its halfway point. Keeping the volume low will help prevent damage to the tubes in the radio.