Lately I’ve been looking at a revised amplifier design based on the Marblewood project. The intent of the redesign effort is threefold. First, a different and more widely available rectifier tube. Second, an improved, if slightly more complicated, power supply design. And third, some potential improvement in the low frequency response. As it turns out, you can’t always get what you want. But also, two out of three ain’t bad.
Continue readingIt never ceases to amaze me how much test equipment I have seemed to have accumulated in the last 40 years or so. And some of it has been largely overshadowed by the continuing march of technology. It seems that everything now is so feature packed that lots of the old equipment is (nearly) totally obsolete.
Continue readingThis topic is just the gift that keeps on giving. I first introduced the 4S preamp with the volume control on the output almost 12 years ago. And yet there still seems to be a tremendous number of misconceptions about the concept and performance ramifications of volume controls on the output instead of the input. This time the misunderstandings surround an output buffer cathode follower.
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