Photo: John Zdralek

The old guitar amplifier on the table in front of me was almost as old as I am. You would think that it might be time to retire the old, tattered box of outdated electronics. But, just a day or two before, the owner had pleaded with me, as I tried to prepare him for the worst. “My dad taught me how to play on that amplifier. Can’t you do something?” And I, being a little soft-hearted (and perhaps a bit soft-headed), assured him that I would see what could be done.

So here I was, with glass vacuum tubes spread across the table, plugging first one and then the other into the ancient tube tester to check for problems. Although tube amplifiers have experienced a resurgence in the last few years, there was a time when most serious guitarists wouldn’t have thought of using the old antiquated technology. The transistor rendered the bulky and fragile glass tubes obsolete back in the sixties and most amplifiers since then have utilized the hardy, space-saving semi-conductor transistors that paved the way for today’s computers and smart-phones. I know next to nothing about working on solid state amps, but I do know that the heart of the old tube amp was the tube itself. So it was that I found myself surrounded by the outdated tubes, testing them on an outdated tester.  

Using the test guide, I would set the buttons to run the correct voltage through each tube, allow the tube to warm up a moment, and then push the test button to see if the circuit was complete. A simple process. The only problem was that when I got to the end of the assorted tubes, all of them had tested out at about ninety percent of their original strength. I examined the wiring in the amp chassis, but there were no breaks, no bad solder joints. What was I to do? I was stymied for a moment. Then an idea hit me.

I put each tube back into the tester, but this time, instead of simply testing the circuit, I pushed a little button on my tester marked “life test” while holding down the test buttons. This placed a load on the tube, simulating what would actually happen when an instrument was being played through the amplifier. I went through several of the tubes with no different result than the first time, but just as I was starting to think that I was on a wild goose chase, as I tested one of the very last tubes the meter reading plummeted when I clicked the life test switch. The reading ended up at about thirty percent for the tube, a completely inadequate output for regular function of the circuit. I had located the problem!

The repair was simple, but painful. It would be nice if I could have made a simple adjustment with a screwdriver, or tapped on a loose terminal. After all, it was just a small problem, only one out of many tubes. It worked fine most of the time. Surely, I could just tweak it a little. Alas, it was not to be. The old tube went into the trash and a new one took its place. Reassembling the amplifier, I gingerly flipped the power switch, joking as I did about the “smoke test”, a reference to the possibility that smoke would be rolling out in a second or two, indicating a complete failure of the process. There was no smoke. Attaching a guitar, I strummed the strings and was rewarded by a warm, clear tone coming through the fifty year old box loaded with wires, tubes, and a speaker.  The operation was a complete success!

May I relate one other experience to you quickly? When I was twenty years old, a wonderful horn teacher agreed to give me a few lessons. I was excited, until he told me what was required. He had noticed that I had no stamina in playing high passages, nor did I have a stellar tone.  He also noted that the mouthpiece was sitting on my lips in an odd position for playing the horn. The solution? He wanted me to start over. Yes, start over. I had to learn how to play the horn again, moving the mouthpiece up much higher, so that more of my upper lip was in the cup than before. It hurt. It sounded horrible. I hated it and I desperately wanted to quit. But I kept going, working through the drastic change until one day, I realized that it didn’t hurt anymore. The tone was really good! I could even get through a complete rehearsal without buzzing my lips like a horse to get the feeling back in them. A drastic solution for a serious problem, but the result was worth it.

Have you had a few times when the “life test” button has been flipped and held for awhile? Did you pass the test? Did you hold up as you should have? I’ve had several times recently when I failed that life test miserably. I have said many times that I am not the person I desire to be. I’m realizing that the process of becoming that person will not be a simple one. Like my horn playing, I may need to start over completely with some things which I have been doing most of my life. It would be nice if a couple of minor things could just be tweaked. I’m pretty sure that it won’t be that simple.

I think I’m ready for the replacement parts to be installed, although I’m dreading the actual process. It may hurt. I will probably hate it. But, I’m pretty sure that the end result will more than make up for the discomfort of the procedure. I’m willing to chance it.

How about it? You know where you’ve failed the life test. Are you ready to get back into action again? Old habits, old attitudes, old sins; they’ll all have to go first.

Drastic measures to make drastic improvements. It will be a good trade-off.