Opto 2A

Opto 2A small
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This iconic unit from the 1950s is the compressor that started it all! A broadcast and recording studio legend, the Opto-2A’s continued use over half a century after its inception is a testament to its brilliance. Its exceptionally warm sound and gentle compression character make it a beloved piece of audio engineering for generations of artists and producers.

The key to its unique personality is the T4 optical attenuator, the outcome of time spent developing optical sensors for the US military. Its sonic signature is the two-stage release which greatly contributes to its smooth and musical compression. With only Gain and Peak Reduction knobs to adjust, the Opto-2A is exceedingly simple to dial in. And with a turn of the switch, the compressor becomes a limiter!

Although the Opto-2A is infinitely versatile, it’s best heard on vocals due to its incredibly pleasant response to the human voice. Definitely try talking or singing through it to hear its impact on your performance.

Some specifics

• The compression ratio varies depending on the source signal.

• The average attack time is fixed at 10 milliseconds.

• The initial release time is around 60 milliseconds for 50% of the release, with the rest occuring gradually over 1 to 15 seconds before the signal goes back to 100%.

• The release timing responds to the length and strength of incoming signal. Under prolonged heavy compression or above-threshold signal level, the release time is slower. Likewise, if the signal is below-threshold, the release will be faster.