These Go To “11”

The year was 1984. The spoof “rockumentary” titled “This Is Spinal Tap” was just released to theaters and it was then that this immortal phrase entered the modern lexicon. I’m referring, of course, to that classic line “These go to 11”.

In the intervening 40 plus years, a million and one jokes have been made about things that go to 11; including amplifiers. As amp builders we would like to know what it takes to make our amp projects go to 11. Unfortunately, the answer is more complicated than you might think.

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Words With New Meanings

Today marks five weeks since I hurt my ankle. And this morning I managed to do my full mile plus morning walk without any issues. My dog was happy about this as well. At 18 years old the definition of “walking it off” after such an injury meant maybe a day. I guess now over 40 years later “walking it off” means five weeks. Who knew?

But I’ve also made a slight deviation with the 6V6 Curly Maple amp.

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Improving Testing with Modern Technology

There are lots of practices in the DIY world that are more than a little out dated. I’m obviously not talking about using vacuum tubes but rather the methods used in building and testing the circuits we build with them. Many of these test methods came about for very good reasons; perfectly applicable at the time. But as technology has advanced the reasons for many of these practices are no longer valid. And there is really no better example of this than the practice of testing audio amplifiers with square wave (or various sawtooth or triangle wave) signals.

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Talking Substitutions

This topic comes up a lot! Someone will email me with, “I want to build {insert project here} from your web site. But…”. Sometimes it’s just that part availability varies. Sometimes people want to use parts on hand which are slightly different. Sometimes people want to substitute tubes, transformers, or whole assemblies. And sometimes people want to actually change the topology! So at what point is the amp being built no longer the design on my website?

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That “Other” Project

I have been working on the new SET chassis design but that’s not all I’ve been doing. This morning I got a little surprise when I checked on my sump pump under the house. It’s starting the rainy season here and I wanted to make sure everything was ready to go. Unfortunately, I found myself replacing a GFCI outlet and the sump pump that had failed and taken the outlet with it. Since the morning was shot, I decided to finish up a couple of other little projects this afternoon. Last week I mentioned another project, the portable class D amp. We’ll, I took a little time this afternoon to finish off that one.

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Revisiting Past Endeavors

So, I was sitting here on this rainy Sunday morning going through some amplifier designs and looking through my stash of tubes and various amplifier building supplies. While standing there looking at the shelves of vacuum tubes, transformers, and various piece-parts, my eyes drifted up to an amplifier sitting on the top shelf. It was my 6AS5 µ-power UL amplifier documented here. But why was the little amp sitting on a shelf collecting dust? Then I remembered.

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