7 things to know about our VLA-2A

no 1 | The LA-2A was invented by Jim Lawrence, a broadcast sound engineer. Lawrence got frustrated with manually riding volume levels during radio shows in order to keep the sound level consistent. He came up with the idea for a device that would automatically turn down the output volume as the input volume increased, which would do the leveling job for him.

no 2 | The first versions of Jim Lawrence’s leveler date back to the 1950s. Among broadcast companies, the word spread of the device and more and more broadcasters and music studios became interested in buying units of their own. In 1962, the LA-2A was made commercially available through Lawrence’s company Teletronix.

no 3 | At the LA-2A's heart is the T4 optical attenuator. Inside the sealed T4 box is a light source paired with a photoresistor. The intensity of the light source depends upon the voltage and frequency of the sound signal. The photoresistor, in turn, reacts to the light and restricts the audio voltage—thus turning down the output volume as the input signal gets louder. To amplify the limited signal, the audio passes through a tube amplification stage.

no 4 | The LA-2A is known for its slow attack and long release times. But a big factor in the success of the LA-2A is that it’s highly program and frequency-dependent—meaning it treats different sound sources differently and depending on the audio context. One might say the LA-2A is intelligent—it has a very musical way of treating the audio signal.

no 5 | The LA-2A's compression ratio also varies with the incoming signal. It will apply a low ratio on quieter sounds and go all the way up to limiting louder parts of the incoming audio. This is what constitutes the LA-2A’s ability to be both gentle and strong—it keeps the sound source in place without ever making it sound congested.

no 6 | Since the LA-2A does a lot of the thinking for you, no detailed controls are necessary—there is just one Peak Reduction control to set the desired reduction/compression level and an Output gain to bring the audio level back up. It really can’t be easier to use. Just set and forget.

no 7 | To inspire the VLA-2A plug-in, Black Rooster Audio studied an all-original LA-2A unit from 1968. The older units are highly sought after as they have the original T4 optical attenuator. The original T4 has not been in production for decades, and modern-day hardware LA-2As reissues from 1999 and onwards use a modern redesign.