Welcome to Dave’s Lab, where improved sound comes from improved performance. Here, audible and measured performance go hand in hand to achieve the highest measure of fidelity.

Even the best vacuum tube equipment from audio’s golden age contains compromises to allow for the economy of mass production. I take some of the best and most loved pieces of this equipment, search these compromises for worthwhile performance opportunities, and offer appropriate modifications to achieve them. These mods always come complete with an explanation behind the changes made, and full documentation as to before and contact dave buttonafter performance.
Please be sure to check in often. More great mods from the lab will be posted here in the future.

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Short Subjects from the Lab

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A New Look at an Old Friend

Here’s a new mod for your Dynaco SCA-35 or ST-35 that really does improve performance, and has the documentation to prove it.

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Techniques to Maximize Power Tube Life

The original article, which directly addresses the causes of reduced tube life, arc events in power tubes and what you can do about it.

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High Performance Power Supply Modifications to an ST-35 Including Individual EFB Bias

This extensive Dynaco ST-35 revision also includes physical improvements, an external switching heater supply, and more.

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Check Out Our Store!

Click here to view/order high quality replace-
ment boards and EFB power supply boards for your small Dynaco amplifiers and universal EFB boards for just about everything else!