Resonance: intensification of sound produced by sympathetic vibration.

(Shea Trahan) 

Reverberation: the collection of reflected sounds from the surfaces in an enclosure. (Trahan)

Impulse Response

Dolphins or bats use impulse response to hear the surfaces and obstacles in space. A bat screech reflects from the walls and helps the bat to navigate. Dolphins do the same under water. Navigation through ultra-sound is used on ships and to generate pictures of babies in the womb.

Rooms have different and very specific shapes and surfaces. These absorb or reflect sound to different degrees. Sound dissipates or lingers. Cavities create reverb. They are resonating. Every room therefore has a specific acoustic signature. Recorded sound with an acoustic signature can be magicked through a plug-in inside a digital audio workstation, which can filter out the signature and apply it to other recorded sound. The reverb specific to a room (and to the creature that emits the sound) can be applied to any sample of sound.


A convolution reverb generator is included in Ableton 9. Unfortunately, I am using Ableton 10. The plug-in is inaccessible for me. I will not be able to record an impulse response from a bursting balloon and create a digital reverb from it. Being of old and pre-digital age, I have only just conquered Ableton 10 with the help of my sons. I love Ableton, but is not a piano generating reverb just as well?

How to build a foghorn from a piano

First you open an old piano at the bottom and place the zoom recorder inside. All you need is one key, played with one finger, pressing your foot on the sustain pedal. Then, digitally remove the attack, so that nothing but a reverb remains.

Confronted with tidal waves, resonating between rocks, the reverberation in the wooden chamber of my old piano acts like a foghorn. 

Rocks at the Gauldrums beach have hidden resonating chambers that fill with water and breath air. If you listen carefully, sometimes you hear a H-sound, when air is trapped and released under rocks and waves. I held the zoom-recorder at arm’s length into the rocky cavities. From far away, the piano reverb seems to linger above the surface of the sea like a foghorn. A strong wind blows above the rocks and in the distance, you can see Ireland and Islay. The lingering quality of the reverberating piano fills the air like mist and somehow gives an impression of the vastness of space. 

Hundreds of miles away, however, on the island of Berneray, my friend Loriana sat at the North beach and played the whistle.