Jeri Ellsworth was inspired by Cryptonomicon to create this microphone with two razor blades and a piece of pencil graphite. It’s pretty grungy and distorted-sounding, but if definitely works! [via Adafruit]

Becky Stern

Becky Stern

Becky Stern ( is a DIY guru and director of wearable electronics at Adafruit. She publishes a new project video every week and hosts a live show on YouTube. Formerly Becky was Senior Video Producer for MAKE. Becky lives in Brooklyn, NY and belongs to art groups Free Art & Technology (“release early, often, and with rap music”) and Madagascar Institute (“fear is never boring”).

  • tigerzero

    Fantastic project! I <3 Cryptonomicon! I’m on the last book of The Baroque Cycle, too. Now someone needs to try making a galvanick lucifer :-)

  • theophrastus

    First, very interesting, thankee!

    So i’m assuming the vibrations cause a variation in the resistance of the pencil lead itself. Is the pencil lead balanced over the sharp edge of the razors? (can’t quite make that out in the video) How does the length of the lead affect the bandwidth? Is it compression strain in the lead that causes the resistance to vary? (oh and what is the airspeed of an unladen swallow?)

    • jason1729

      The resistance of the pencil lead does not vary. There is a very tiny area of contact between the lead and the razors and as the lead vibrates, the contact gets better and worse.

      Not sure where you’re going with bandwidth, it’s a totally unrelated concept. What compression strain in the lead?

      Cool project, but it makes me sad to see readers see this as some obscure parlor trick. This is really going back to the first principle of “Making”.