FM | PRODUCER’S GUIDE
Universal Audio recently made its LA-2A leveling amplifier plugin free to download for a limited time. For those lucky enough to get hold of it, or with access to any of the many other LA-2A clones (or even the original hardware!), Andy Jones has an in-depth guide to this classic compressor
The Teletronix LA-2A is one of around half a dozen pieces of vintage studio gear that can have grown producers weeping into their mixes, such is its ‘magic dust’ reputation. This leveling amplifier has been with us for around 60 years, and many engineers swear by it for recording many different sounds or adding ‘just that little something’ to a mix. However, there are slightly different viewpoints on just why it is so good, with some citing its transparent and natural sound, while others say it adds lovely warmth and colour. The truth is that it can do all of this and more, but one thing most people agree on is that the LA-2A just sounds wonderful.
The LA-2A is a tube compressor that uses optical compression – unlike the more common FET or VCA compressors – which gives the compressor a unique character. It has few controls with attack and release times set, so neither is adjustable. These are both relatively slow, giving a very smooth character and natural-sounding compression which is particularly good on vocals and bass. You also only get a choice of infinity (limiting) or 3:1 ratio compression set by a single switch on the left. It’s this simplicity and the presence that the compressor adds to a sound – it has enough gain to use it simply as a characterful preamp – that has won it many fans since its development in the late ’50s and early ’60s, and it’s been used to record everyone from Alanis Morissette to Kurt Cobain.
Just why is the LA-2A such a great studio tool?
A very brief history of the LA-2A
The LA-2A was initially designed by ex-naval engineer Jim Lawrence. He was working for a radio station in Los Angeles but was in need of a device to control broadcast volume levels which he had to adjust manually. He devised the first-ever optical compressor, one that used light to control the signal level. The theory is that the hotter the input signal, the more light, which is then applied to a light-sensitive resistor to apply compression. The more light, the more resistance, so less signal and more compression.
It sounds easy but Lawrence had to apply knowledge of optical sensors that he’d picked up while working on the Titan Missile Program to produce the first levelling amplifier, the LA-1 in the late 1950s. Lawrence would form the company Teletronix to manufacture it and its successor, the LA-2, was used by some of the biggest broadcasters of the time, including RCA and CBS.
The LA-2A came out in 1962 and three years later, Lawrence sold his company Teletronix, and it would eventually end up being owned
