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For those that are into audio production you’ll recognize the concept of optical coupling as the basis of the legendary LA-2A compressor.
by CPLX 4y ago
For those that are into audio production you’ll recognize the concept of optical coupling as the basis of the legendary LA-2A compressor.
- buescher 4y agoThe schematic is here: https://memory.loc.gov/master/mbrs/recording_preservation/manuals/Teletronix%20Model%20LA-2A%20Leveling%20Amplifier.pdf https://memory.loc.gov/master/mbrs/recording_preservation/ma...
- lebuffon 4y agoThe LA-2A is great compressor. To be clear it uses a different application of "optical coupling" in that Audio is not passing through the optical connection. The light source is driven by a DC amplifier that generates a control voltage derived from the audio signal. The light shines onto a photo-resistor that is used as the shunt component of an audio pad. (attenuator) As the light intensity increases the pad reduces the signal level at the pad creating an audio compressor.
- CPLX 4y agoYes this is of course correct and a worthwhile point to make. The fidelity of an actual optical transfer function will never be even close enough to the level needed for the transmission of actual high quality audio.