What Is an Echo Chamber?
Special rooms for creating natural reverb aren’t as prevalent as they used to be, but with a little ingenuity you can achieve an echo-chamber effect right from home
It’s sometimes hard to remember that most modern effects are actually a pre-packaged version of an old analog process. Take studio echo, for example. You may have noticed that a lot of records from the ‘50s and ‘60s have an enormous reverb sound, much of it the product of a purpose-built room consisting of concrete or tile and outfitted with a loudspeaker and microphone. These so-called echo chambers (also known as “live chambers”) were often quite small (usually around 10 to 15 feet long on average, with a low ceiling), yet the best ones were capable of achieving a reverb “tail” that could last several seconds or longer. Chambers came in various shapes and sizes, but because they were handmade the best ones had a trademark sound—in fact, music buffs can often tell where a song was recorded just by the sound of the chambers. So remarkable were many chambers that even today recording artists flock to the likes of Abbey Road Studios, Capitol Studios, and other mainstay facilities to hear these artifacts in action.
With increasingly sophisticated plugins now able to replicate these effects in the box, today live echo chambers aren’t nearly as prevalent as they once were. However, their legacy remains—and there’s nothing wrong with trying to emulate a live chamber at home, using an existing space such as a shower stall, a hallway, stairwell, or garage as a way of adding something totally organic to your work.
How an echo chamber works. Engineers achieved the echo effect by feeding a dry recorded signal from the console into the chamber through a speaker situated at one end of the space, with a microphone on the opposite side picking up the “treated” sound and returning it to the recording console, to be blended in with the main tracks. Adjusting the reverb decay, as well as its shape and color, simply became a matter of increasing or decreasing the signal to the loudspeaker, or moving the microphone closer to or farther away from the speaker. You could also alter the tone of the echo by manipulating the EQ of the signal fed into the chamber. Most importantly, engineers would typically insert a tape delay on the way back to the console (known as “pre-delay”), thereby slightly widening the gap between the dry, untreated signal and the sound coming from the echo chamber.
Though a number of chambers were expressly built for creating echo, others were the product of a “found” space within the studio facility that included attics, hallways, stairwells, even emptied water-storage tanks. Back in the 1950s when Columbia Records needed echo at one of their New York studios, all they did was take an old concrete basement storage space, installed a mic and speaker, and that became one of the best-sounding chambers in all of popular music.
Homemade echo. If you’ve got a hankering for some DIY reverberation, there are numerous ordinary household devices which themselves offer chamber-like qualities—a tiled bathroom, a portion of a basement, an interior or exterior stairwell. All you’ll need is a small speaker placed in one corner of the space, and a microphone facing away from the speaker in the opposite corner. Connect the speaker to the output of your recorder and run the microphone to any open record track. Send the untreated track to the speaker, then record the sound of the reverberation on a separate channel. Once complete, all you have to do is blend the dry and wet tracks together until you achieve the desired results. And as mentioned above, adding a touch of delay to the returned signal will help to enhance the reverbed sound. Try it sometime—if it doesn’t work out you can always go back to your built-in digital reverbs, but don’t be surprised if you like the idea of creating a usable effect that doesn’t come straight out of a box.
Community
Connect with BMI & Professional Songwriters