The first digital reverb to hit the market was way back in 1972, when the German manufacturer EMT who were enjoying dominance with the in studios around the world with their EMT 140 Plate Reverb, introduced the EMT 144 Digital Reverb. The EMT 144 was a rack mount design with very limited capabilities and as such was not very successful. Few of these classic old digital reverbs remain in existence today. In 1976, EMT joined forces with American electronics company Dynatron to develop the now legendary EMT 250 digital reverb. Looking like something from a sci-fi movie, the floor standing EMT 250 was almost novel in appearance, but it’s incredible performance would ensure it became a mainstay of studios the world over. The EMT 250 was updated to the EMT 251 which offered increased bandwidth, additional programs with additional parameters to tweak the reverb programs. In 1978 American company Lexicon released their competitor to the EMT 250, their Lexicon 244 digital reverb, a reverb that to this day is still being used in studios today.
Algorithmic Reverb All early digital reverbs are algorithmic reverb designs. Algorithmic reverbs are essentially delay lines that repeat on themselves to simulate reverb decay. The ‘algorithms’ used tweak each repeat usually with modulation and various other filters. Some of the worlds most loved digital reverbs such as the EMT 250, AMS RMX 16, Lexicon 224 and Lexicon 480L are all algorithmic reverbs. It is clear that not all algorithmic reverbs are created equal, and it is why to this day, those reverbs are so revered, their algorithms are superior to other manufacturers.
Convolution Reverb Convolution reverb is to reverb what sampling was to keyboards. Convolution reverb involves measuring a live space, and using this ‘impulse response’ applies it to the incoming signal to simulate that real space. Convolution reverbs works exceedingly well, and provides very realistic reverb. Early hardware reverbs to use convolution techniques were the Sony DRE-S777 and the Yamaha SREV1.
Reverb Plugins Today plugins like Audio Ease Altiverb provide hundreds of impulse response reverbs in a plugin format. Some of the ‘real’ spaces provided with that plugin are quite breathtaking. In particular, the Great Pyramid of Giza, a space no one will ever get to record in, sounds phenomenal. Most reverb plugins these days are either algorithmic, or convolution, and with today’s computer power, we can enjoy the very best sounding reverbs possible and for far less that what a hardware reverb costs. However, there is still some kind of magic in these older hardware reverbs that most of us just can not let go of.