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Old 30th March 2019
Lives for gear

Originally Posted by FabienTDR View Post
This is a bit like saying: The biggest problem of modern rockets is the shape of their sails. It sounds cool to laymen, but of course it doesn't make any sense.

A dynamics processor is something taking a value, and returning one. Instantly.

Here's a dynamic range compressor:

y = tanh(x)

What exactly is the problem of finding out the value of y?!

A compressor doesn't have to "wait" for results. It simply looks at the input, and returns an output. Maybe the best counter example, perfectly showing how ridiculous this idea of a "delay problem" is: Digital clipping.

No. There is no general problem. Zero difference to analogue circuits. Takes an input, returns an output. Simultaneously.
This is true for analog. Not for software. In software a measurement has to be taking, oh it's volume 5, so X=5. Then that goes into the software, get's your math done to it. then that reports back to the signal and adjusts the signals level. It takes at least one sample, and very often many samples for the signal to have it's level changed. The first sample of "Too loud" does not get compressed unless some "look ahead" is built into the software. This is typically the case. That introduces lag.

So sure it can work that way. But in the digital world, at the cost of lag. In the analog word, no lag required. Even though in practice, they way compressors are designed, it's lag rate is commonly what's desirable about how it operates.