Re: Compression
The concept of look ahead involves using prior knowledge of the future so you can ramp gain changes slowly, and still get there in time to prevent overload or some other situation. The amount of look-ahead time matters. You need to see enough of the signal to impute useful gain change information.
In recording this look ahead is often performed in non real-time, so you could look ahead the whole performance, say for mastering. Non real-time processing involves tricks like half speed mastering, to double the apparent HF bandwidth of a cutting lathe, or even running recordings backwards to trade sudden attacks, for gentle decay envelopes.
Back to live processing, with stand-alone boxes we do not have the flexibility to perform delay alignment, so this is, in my experience, limited to noise gates that get a lot of benefit from a short delay. For general dynamics processing, more is better and several mSec can buy enough time to smooth gain moves so this is great feature for use inside a digital console. Besides the look-ahead, digital dynamics side-chains can use digital decision making and processing power to reduce audible artifacts.
Are we far enough off the reservation yet with this veer?
JR
