Zeppelin Design Labs Cortado MkII Contact Mic DIY Kit

The Cortado MkII Balanced Buffered Contact Mic kit contains a phantom-powered circuit that balances the signal from a piezo transducer and matches its high output impedance to the low input impedance typical of consoles and recorders. Please note the MkII is only offered as a DIY kit.

MkII Features:

• Extended low-end response for full, rich sound
• Adjustable bias for optimal performance
• Crazy-low noise floor
• The kit includes all the parts needed to build a Contact Mic or an Instrument Pickup.
• Cortado MkII can be adapted into a fabulous Tin Can Mic, as detailed in our Instructable.
• The Cortado MkII requires Phantom Power.
• Bulk mic cable is available to extend cable lengths.

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Piezo sensors are quite incredible little things.  They can be used to detect the slightest variation in pressure, force, or strain and convert that energy into a voltage.  Over the past several decades they’ve been used in numerous applications in several fields including the audio industry.  Unfortunately, they’ve developed a bad reputation for sounding “harsh” and “brittle” when used as contact microphones in acoustic instruments.  This is due to improper impedance matching and the inadequate driving circuits that are mostly used with these sensors in audio applications.  Piezo sensors in themselves are capable of a very wide bandwidth, and when used properly, can achieve excellent results.  So with the intention to get the most out of a piezo sensor, we are offering the Cortado Balanced Piezo Contact Mic.  This mic contains a phantom powered circuit that properly matches the piezo sensor input impedance and drives the signal via a balanced output, which allows for wide bandwidth (~20Hz-30kHz), low signal losses, and high signal to noise ratio.  The Cortado’s circuit was originally designed by Alex Rice for use in his contact mic hydrophone, but it can be used in countless more applications with excellent results. In the recording studio or on stage it can be used on pianos, guitars and other stringed instruments, or even percussion.  It can be used as a plate reverb pickup or wooden stomp box mic.  We even created this Tin Can Microphone out of stuff we found in the trash (as illustrated in the product photos).
The Cortado is also the perfect accessory for a low-fi geek or a field recording enthusiast.  Discover the sounds inside the pipes in your apartment building, or in bridge suspension cables, even in melting ice.  Anything that vibrates or resonates with an audible frequency can be captured by this contact mic.  Several field recording enthusiasts around the web use this circuit to record some pretty cool stuff; check out these links:

Cortado Field Recordings
The First Rule of CONTACT MIC Club
Getting Connected With Contact Mics
Building Contact Microphones

The Cortado kit includes everything you need to build the circuit, complete with a male XLR output, mounting hardware, and several shielding options.  Requires phantom power.

The Cortado MkII is under the Creative Commons Share-Alike license, which means you are free to add or build upon this circuit idea in any way your creativity allows, but any derivatives must be shared using the same license.