The lovely folks at work thoughtfully presented me with a DIY Bottlehead Crack OTL headphone amplifier kit. Why would one want to solder, assemble and test something that has enough electricity running through it to kill someone? Because engineering.

Ok so step one, tubes are mysterious glass enclosures so we need a surface that will accentuate said depth. let’s paint the top of our metal plate to give it some depth.

Oh and I didn’t get it right the first time, sprayed too much and it dried strange; acetone to the rescue!

Paint that metal!

The rest of the build was pretty fun, it would have been way easier to simply add in all the upgrades during the initial build as desoldering larger resistors and caps in tight spaces was tough.

Let’s get started!

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And now for the transformer and some hookups.

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Connecting all the power to the tubes..

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And done!

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Now for the Speedball upgrade! This should give us a lot more fidelity and clarity on the edges of the sound waves.

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Now hooking it all up and plugging in my Beyerdyanmic T90p, it sounds awesome!

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