The Poor Man's Reverb
Well, like the old saying: "Necessity is the mother of invention". Well, that may not apply here precisely, but it sounds much less suggestive than the saying: "if it feels good, do it".
Anyway today, any CB'er can go to their handy radio supply store, and buy a microphone which will give them an "echo" sound. The popularity and proliferation of such devices has pretty much negatively tainted this effect, as little more than a nuisance. But back in the mid 70's however, before the advent of digital delay circuits made this such an easy task, people had to be a bit more "inventive" if they wanted to create sound effects. The most common method of generating a reverb effect at the time, was used typically for either guitar or automotive sound enhancement, and contained mechanical springs which the audio passed through. The vibrations induced in the springs, as the audio passed through, produced the "reverb" effect. One could install such a device in series with a mike audio wire and, with the proper amplification and impedance matching, would have a fairly good reverb effect. Even more imaginative and enterprising people could create an actual repeating echo effect by using a continuous loop tape recorder with separate record and playback heads. The time delay between the recording (Determined by the tape speed and the distance between the two heads) and playback would determine the degree of echo delay. Some people experimented with adapting these various units to their CB microphones as well, so that they could play "space alien", or other games (Like in this audio clip). Most of these devices could be made to sound good if they were connected properly, and the audio levels were kept to a reasonable level. There were a few memorable locals, who were fairly proficient at "putting on a show" with sound and echo effects, and they always managed to create a whirlwind of comments as a result.
It was late 1974 or early 1975 and I, of course, being someone who craved both attention and technical challenges along with a mischievous side, wanted a piece of this action. But lacking the financial capital to do it right, I was forced to be a little more innovative and off-the-wall. What I came up with was really simple in concept. As any kid who has ever yelled into a large metal can can tell you, there is certainly some reverberation there. But not nearly enough to make for a really "cool" sounding echo. Remembering how reverbs worked with springs, and just on a hunch, I took your basic 2 LB coffee can (I think it was Maxwell House), and started experimenting with soldering springs to the bottom. Adding the springs greatly increased the reverberation effect of the hollow can. After some testing, I finally settled on an 1/2" diameter, 8 inch spring. I could then hold the contraption over the head of my D-104, and presto, instant reverb! As can be expected, it was not as clean sounding as a "real" commercial unit. But it did give an honest to goodness echo effect, for those brief moments when something like this was deemed "appropriate". Another advantage to this reverb, was that it required no power, or no electrical attachment to the radio equipment. It was, therefore, very portable and it could be used with any radio, although an amplified mike was required for maximum effect. I used this gizmo for a few years, anytime I needed a little "depth" while clowning around, or during the many radio comedy bits that we produced at random.
Ironically enough, by the time technology made the task of creating echo much easier, my desire to further pursue it had faded. I guess when something becomes commonplace enough that the average person can just buy them, they lose their appeal to us techies, who enjoy uniqueness and the idea of "going where no man has gone before".