Threshold Receiver Workshop at COSMOS, Lisbon – 14 Nov 2026

THRESHOLD RECEIVER
A radiophonic listening and building workshop with Wouter Jaspers

The city is full of signals we were never meant to hear. Power lines, transformers, tram cables, phone chargers and shop security gates all leak electromagnetic fields into the air around us. Below them, at very low frequencies, the atmosphere carries the crackle of lightning from storms thousands of kilometres away. Even solid matter has its own voice: railings, windows and bridges vibrate with the life of the street and the wind.

The THRESHOLD RECEIVER is a small, hand-built instrument for listening to this hidden layer of sound. It combines three ways of hearing in one device: an induction receiver that turns electromagnetic fields into sound, a VLF (very low frequency) receiver for natural radio phenomena, and a contact microphone, sensor and probe input to capture the vibrations inside materials. All of it comes together in a headphone output so you can listen while you explore.

Sound samples

VLF/Natural Radio (and statics from my sweater picked up by antenna):

VLF Receiver section heterodyning sounds, feedbacking with the headphones:

The internal sounds from my recording device (induction coil pickup):

A piezo microphone connected to the Input, in a bit of straw, with character engaged:

Here some pics from prototyping:

Building and listening
Each participant solders their own receiver from a kit designed especially for this workshop. No experience with electronics or soldering is needed: the kit is deliberately simple, and every step is explained on the board and by Wouter in person. Once the receivers are working, we take them out into Lisbon and listen to the city as an electromagnetic landscape.

Dates and tickets
The workshop takes place on Saturday 14 Nov 2026 at COSMOS in Lisbon in the afternoon from 14:00 – 18:00. The workshop will be taught in English (with occasional German, Dutch or Basic Portuguese when needed). Ticketprice for the workshop is €60, which includes the Threshold Receiver kit, contact microphone, antenna and instructions. The workshop is limited to 15 participants, so tickets must be bought in advance, full=full!

The workshop is fully booked

The Threshold Receiver Workshop on 14 November is fully booked. In the form below I will gather a few people for a small reserve list for when participants drop out or cancel. Please fill out below if you would like to be on the reserve list (no advance payment needed, I write you if somebody drops out, could be last minute.)

But do not worry when you want to play around with radios! On Sunday 15 Nov 2026 in de afternoon COSMOS will host a Open Radio Experimentation Lab (free entrance), where you can try out a bunch of different receivers, we can nerd out and where you can build you own personalized antenna for the Threshold Receiver. There will also be a concert in the evening. Bring your own radios and we make antennas for those too, after which you can hit the streets and hunt for signals.

Questions? Send me an email!