A Brief History Of Reverb

The intentional positioning of sound within a particular space for creative effect has always been part and parcel of the music production process. From the first time a room was chosen for recording in based on its acoustic properties, all the way through to the conjuring up of spectacular virtual environments using the hyper-real likes of Reverberate 3 and Seventh Heaven.

Indeed, reverb could be accurately described as the original studio effect, predating even compression and EQ by several decades. Let’s start at the beginning…

Rooms & Chambers

In the early 20th century, pioneering recordists experimented with microphone placement and room selection in order to add characterful ambience and a sense of scale to their recordings. While this straightforward harnessing of acoustics proved perfectly effective to a point, it was a decidedly low-tech and inflexible approach that obviously afforded nothing in the way of control and configuration.

That’s not to suggest that room reverb has ever gone out of style, though, and many seminal tracks over the decades since have proven that extraordinary results can be achieved by directly recording musicians in real-world spaces, from Jon Bonham’s stairwell-hosted drum sound on Led Zep’s ‘When the Levee Breaks’, to Tony Visconti’s ingenious triple-mic vocal setup for Bowie’s ‘Heroes’. Nonetheless, back in the day, the dependence on actual rooms was a profoundly limiting factor in the recording process.

It wasn’t until 1947 that legendary engineer and Universal Audio founder Bill Putnam came up with what’s widely recognised as the first ever artificial reverb. While working on The Hamonicats’ track ‘Peg o’ My Heart’, Putnam placed a speaker and microphone in the studio bathroom to create an echo chamber, through which the band were recorded to create a weird, ear-catching reverberation effect that no doubt helped the single climb to the top of the charts.

Hall

Putnam’s eureka moment proved pivotal, and the echo chamber soon became an essential and sonically influential fixture in all the major recording studios of the day – perhaps most famously Capitol Studios (four Les Paul-designed trapezoidal chambers buried 30 feet underground), Abbey Road Studios (one chamber for each of its three studios), Hitsville USA (an untreated attic space that came to define the sound of Motown) and Gold Star Studios (two chambers that played a key role in the construction of Phil Spector’s ‘wall of sound’).

Whilst the famous chambers at Abbey Road, Capitol and Goldstar left an iconic sound on countless records they share common reverberant characteristics. The rooms are reasonably small, so have a very fast attack and they build echo density quickly due to the low distances between walls. They tend to have hard reflective surfaces to maximise the decay time, usually achieved with tiled or plastered surfaces. To reduce flutter and ringing, a trapezoidal room shape is often desired such as those at Capitol, or objects may be placed within the room such as the large vertical pipes in Abbey Road’s chambers. The rooms are often quite bassy, so much of this would usually be EQed. The Abbey Road technique is often discussed online is often used with plates and chambers – this uses bandpass filters to cut lows at 600 Hz and highs cut at 10 kHz.

Heavy Metal

With reverb firmly established as a studio essential, various companies started exploring ways in which to recreate the effect mechanically, so that smaller recording facilities could offer it to their clients without building their own chambers, and greater control could be taken of the sound of the reverb itself. The most historically and technically significant of these was German firm EMT’s groundbreaking (and back-breaking!) plate reverb, the EMT 140 Reverberation Unit.

Released in 1957, the EMT 140 comprised a massive wooden box housing a steel frame, which in turn held in place a thin, spring-mounted metal sheet (the plate) with a transducer and pickup attached to it, the first setting the plate in motion when a signal was received, the second recording the resulting vibrations.

Not only did this 270KG monster yield truly stunning reverberations, but through the adjustment of its motorised damping mechanism, the reverb time could even be shortened. It was radical stuff, although still very much a high-end option for only the most well-off studios.

Plate Reverbs - EMT140

At around the same time, Accusonics – an offshoot of the Hammond Organ company – found great success with their much more compact and affordable spring reverb technology. This worked on the same basic principle as its plate counterpart, but substituted the enormous metal sheet for a set of small springs that generated a, well, springy kind of sound that worked particularly well on guitars. Originally built into Hammond’s organs exclusively, the incorporation of the Type 4 Spring Reverb into several of Fender’s guitar amps, and the breaking out of the design into various dedicated devices, at last gave the musician in the street access to workable artificial reverb, albeit clearly not in the same league as the plate in terms of density, frequency response and overall sonic class.

Plates are of extremely high density, so are very thick sounding. Like chambers, they have a very fast attack creating an immediate rush of reverb. They feature dispersion – low frequencies are delayed compared to highs; spreads transients, creates stereo depth and a whipcrack sound (you can read more about dispersion in a previous article on plate reverb). Plates are often used on vocals or to supplement existing verb – since they have no reflections this can avoid room-within-a-room. The reverb time at low frequencies is typically much longer than at highs in a plate, as you can see in this image as reverb times increase the low frequencies extend proportionally much more than the highs, another reason the Abbey Road technique is used with plates.

The Digital Age

EMT changed the game once again in 1976 with the launch of the world’s first digital reverb, the EMT 250, built in conjunction with American manufacturer Dynatron. (In fact, 1972’s EMT 144 was the first digital reverb, but it was so rudimentary and under-supplied that it can be largely overlooked.) Marketed as a digital version of the EMT 140, the 250 was a comparatively mobile floor-standing unit that actually went several steps beyond the capabilities of its forebear, generating chorus, phaser and delay effects as well as reverb, and sounding absolutely phenomenal doing it. Marking a turning point in pro audio technology, the 250 was followed four years later by the EMT 251, which upped the processing from 12-bit to 16-bit, extended the frequency response and expanded the control panel. 

With the EMT 250 costing $15,000, the market once again demanded a cheaper alternative, and it initially came in the shape of Lexicon’s 224, which landed at half the price. From there, it didn’t take long for digital reverb to achieve ubiquity in professional and home studios around the globe, and the next couple of decades saw a raft of increasingly affordable and powerful models launched by an array of manufacturers including Eventide, TC Electronic, Roland, Yamaha and Alesis.

It must be said that the emulations presented by these unarguably wondrous devices didn’t often sound all that convincing, but their synthetic, glossy textures, unnatural characteristics and criminal over-use were hugely influential on the sound of music in the 1980s, from Phil Collins and every power ballad of the time, to Vangelis and Eno/Lanois. In the decade of excess, it seemed there was no such thing as too much reverb.

A huge milestone in the development of digital reverb hardware was hammered into the ground by Sony, whose 1997 DRE S777 unit blew our collective mind with the introduction of real-time convolution processing. Without relying on FFT techniques to lessen the load, it uses a brute-force FIR implementation using various custom silicon.

While regular algorithmic reverbs generate their imaginary spaces using networks of delay lines, convolution reverb uses impulse responses sampled from real environments and spaces to emulate them with unparalleled realism. The captures painstakingly taken by Sony stand as some of the finest ever made, and despite the efforts of some key reverb figures in the industry Sony have never been convinced to make them available for use in newer designs. You can read more about the differences in this article about convolution vs algorithmic reverb.

The pinnacle of digital reverb design to date is Bricasti’s M7 algorithmic processor. Released in 2008 it is still considered by many to represent the last word in hardware reverb, eclipsing what were the final designs of other great manufacturers like the Lexicon with the 960L or Eventide with the H8000, its beautifully organic-sounding tails and supernatural transparency genuinely competing with the physical fidelity of convolution. It has a wonderfully subtle approach to modulation, and is one of the most transparent reverbs ever made making it particularly suited to score mixing with a wonderful low end processor creating particularly convincing small rooms. 

The Software Revolution

As the turn of the century saw the arrival and rapid rise to dominance of plugin technology in the Mac/PC DAW, software emulations of classic reverb devices and all-new designs brought with them clear advantages in pricing and convenience, and matched or exceeded hardware in the performance arena. Still, it was those early analogue and digital ’verbs that laid the foundations for the high-concept plugins we rely on today, and they serve as crucial reference points for everything we do at LiquidSonics. You can read more about our pioneering capture and playback technology Fusion-IR which was invented to tackle many of the shortcomings often associated with convolution reverb.

Our range of plugins employs both convolution and algorithmic techniques, and spans the gamut of reverb types and styles, from classic hardware emulation to sophisticated surround treatments. Lustrous Plates recreates no less than seven (with more coming this year) classic plate reverbs – including the EMT 140 – with the innovative Temporal Acoustic Spectral Mapping (TASM) technology at its core it provides far more control than you’ll find in any other plate emulation. Cinematic Rooms and Illusion deliver breathtaking rooms, halls and other spaces for post and music production respectively. Seventh Heaven brings you a sublime convolution-based recreation of the Bricasti M7 with dedicated Fusion-IR engines for playback of discrete captures of the reverb, reflections and very low frequency processor; while the flagship Reverberate 3 is the ultimate reverb toolkit modelling a variety of iconic boxes and rack-mounts, as well as a wealth of rooms, halls and more.

Try a free 14-day demo of any of our reverbs and hear for yourself why with LiquidSonics reverbs you can find a space you can believe in.