Threshold Receiver – Electromagnetic, VLF and Sensor Receiver

Power lines hum, chargers chatter, screens buzz, and on a quiet night lightning crackles from hundreds of kilometres away. All of it is electromagnetic, and none of it is audible, until you plug in a pair of headphones and switch on the Threshold Receiver.

How it works

• Antenna: the wire antenna picks up very low frequencies (VLF), from mains hum to natural radio such as the sferics of distant thunderstorms.
• Coil: the pickup coil on the board hears the magnetic fields of transformers, chargers, screens and motors.
• Input: plug in the contact microphone (or a piezo, sensor or probe) and listen to vibrations in walls, windows, tables and objects.

An input selector chooses what you hear, and three switches shape it: Air / Touch, Field / Sky, and a Soft / Open / Dark character switch. Volume control, headphone output and an on/off switch with LED.

Choose your version

Both versions run on a 9V alkaline battery, which is not included.

Pre-order

5 Nov 2026: I ordered all the parts for the Threshold Receiver kits and those are currently on the way to Berlin. Right now the Threshold Receiver is available as a pre-order until 30 November 2026, limited to 75 units.

All orders ship in the first week of December 2026 in the order I received them.

What’s in the box

• Threshold Receiver: DIY kit or finished unit
• Wire antenna
• Contact microphone
• Build Instructions / Manual

Not included: 9V battery and headphones.

Building the kit

All parts are through-hole, so the kit is suitable for beginners: in my workshops people build it in a single afternoon. You need a soldering iron, solder and a flush cutter.

Specifications

Listen

Here are a few audio examples, check out more on my instagram.

Rather build it together with others? Join the Threshold Receiver Workshops (12 Dec 2026: Keith Bar, Berlin, 16 or 17 January 2027: Brussel (tba) and 14th of March 2027: OCCII, Amsterdam)