The History of EMT and Plate Reverb

​If you’ve spent any time using any of the vast variety of reverb plugins available today, there is no doubt that you’ve used one that was based on EMT’s (Elektomesstechnik) 140 Plate Reverb.

It sparked debate only decades ago, as many major studios and engineers began to shift towards using this artificial reverb rather than the rooms or chambers they were using prior.

To truly understand the significance of the EMT 140, we have to travel back even further to grasp how reverb was produced before its time.

History Of Reverb

While the use of reverb has been around for ages in music thanks to the natural echoes created by everything from large cathedral halls and small studio rooms, it wasn’t until around 1947 that the first recorded performance with reverb was released.

A band known as the Harmonicats was the very first group to use an artificial echo chamber to create space within their music on their hit song, “Peg o’ My Heart”.

Bill Putnam, the group’s producer, decided to stick a microphone and a loudspeaker in the bathroom of the studio to give the harmonica a more ethereal sound in the recording.

They probably knew they had done something great after the song hit number 1 on the charts for an entire summer. It was at this moment that the entire idea behind artificial reverb innovation would begin expanding into what we currently have today.

​This type of reverb became known as an “echo chamber”. Studios all over the world including Gold Star Studios (Phil Spector, Beach Boys), EMI (The Beatles), and Capitol (Frank Sinatra), made use of echo chambers, as they built these non-parallel-walled, shellac-based surfaces in their studios to get that acoustically reflective sound.

Speakers and microphones were then installed into these rooms to help capture those reflections so that they could be mixed into the music.

​Introduction of the Plate

As more and more engineers were on the hunt for ways to control and manipulate reverb more efficiently, they finally found their answer in 1957. This was the year that German company EMT came out with their breakthrough device: The EMT 140 Reverberation Unit, otherwise known as the “first plate reverb”.

It was a smoother and more natural substitute for the widely used spring reverbs that were found in Hammond Organs, and far more conscious of space than large echo chambers. It helped to simplify the process of recording with reverb, as well as made it much more versatile to work with.

Even with that said, they still weren’t convenient to today’s standards, as these devices were about 8 feet x 4 feet in size and weighed just over a quarter of a ton.

​How Does It Work?

The EMT 140 used an electromechanical transducer, similar to one that you would find in a loudspeaker, that helped to create vibrations through the plate.

That plate was made from thin steel suspended between tubular steel frames. Pickups, like those you would find on an electric guitar, would capture these vibrations as they moved across the plate and output them to the console.

While the original release was only available as a mono reverb, the company ended up releasing a stereo model in 1961.

The coolest thing about the EMT 140 was the ability for engineers to manipulate the reverb time. A damping plate was hung parallel to the steel plate and could be moved closer to the steel plate with a wheel or remote control.

Though they would never actually touch, the absorptive material on the damping plate would cut down reflection times all the way to a minimum of 1 second at 500 Hz.

What Was It Used For?

If you listen to many of the hit records of the 1960s and 1970s, you’ll likely hear the unique sound of plate reverb. While they sounded more natural than spring reverbs, you could hear the “metallic” sound of the plates that gave it more of an artificial feel.

The beauty of it was, this tone was perfect for blending with certain instruments and sounds!

The best words to describe a plate reverb are: bright, smooth, and dense.

These metal plates, more than anything else, allowed  higher frequencies to travel much faster than the lower frequencies. This has a lot to do with why we hear brightness when we listen to the sound of the EMT 140 reverb.

When listening to your favorite records, even today, there is no doubt you’ll hear them used on vocals, snares, overheads, acoustic guitars, and more! The distinct coloration of the EMT 140 altered the timbre of many instruments in ways that now tickle our ears.

Move Into the Digital Age

As music technology moved further into the digital age with the use of effects like delays, there became a hole in the market for digital reverberation.

Engineers were also tired of the large amount of storage space the EMT 140 Plate required.

This is when EMT had the wonderful idea to release their digital iteration of the EMT 140 Plate Reverb, the EMT 250. The EMT 250 was meant to take all of the characteristics of the famed EMT 140 and redevelop it into something more convenient and malleable.

In 1976, the EMT 250 was presented at the AES Convention in Zurich by EMT’s Technical Director, Karl Otto Bäder. The EMT 250 took years of research into attempting to create algorithms and correct voicings for this reverb unit that was less than half the size of the original.

​Getting The Sound

While you would be pressed to find any of these units left out in the world today, let alone buy one, as they are priced at tens of thousands of dollars, you can check out the modern emulations that exist in the form of plugins.

UAD’s EMT 140 is easily one of the best 140 modeling plugins around with the same sonic personality as the original unit, though you can also check out Audio Ease’s Altiverb, which provides impulse responses from different EMT plates around the world.