We have recently introduced our new Adaptive Compressor, which is much more powerful than our older compressors, and even sounds great in infinite ratio mode. This has brought lots of improvements; it sounds better, is easier to adjust, and results in extremely consistent results. So all is good, right?
Traditional designs vs our Advanced Compressor
In most audio processor designs, one would use multiple compressors (and AGC's) stacked, after each other, typically with higher speeds but less action near the end. Most of these stages will run at lower ratios, because with traditional compressors, high ratios often sound really bad.
Our new Adaptive compressors can do all of this in a single stage, with infinite ratio. So all is good, right? Well, kinda... At some point, I heard 2 presets that both use Adaptive Mode at infinite ratio. One of the two used slow attack times, and sounded extremely consistent, but it lacked "warmth" and was maybe a bit too much "in-your-face". The other preset used much faster attack times, sounded much warmer, and the faster attack made transients sound punchier, more hi-fi like. But the faster attack also caused audible annoying volume effects (pumping, albeit not really like traditional pumping).
Both effects would be mostly gone if the compressors would run at 1:2 ratio instead of infinite ratio; at 1:2 ratio you can get away with almost anything. But using both presets in series would cause all kinds of annoying effects because they might be fighting against each other, and at 1:2 ratio would still only lead to a 1:4 ratio in total, which isn't enough. Which means that we would need an AGC again, and still loose consistency compared to what we have now. So, bad idea.
The new idea
Instead of putting 2 compressors after each other at lower ratio's, we can run them alongside each other, still at infinite ratio. They both receive the same input audio, and at the end, we combine the outputs. If the output levels of both compressors are similar, that leads to something that sounds close to 1:2 ratio. So as long as both presets don't do the same thing that we don't like at the same time (and we can even run both with different numbers of bands), this will almost completely hide the effect. But the end result is still as consistent as it was before. So this is close to infinite ratio compression which sounds like 1:2 ratio compression!
If one attack or release is faster than the other, attacks and releases will be faster when they start, and we have observed before that that's generally a good thing. So that's an added benefit of combining compressors.
Testing it
Since MB2 is typically not used when using Adaptive mode at infinite ratio, we're using MB2 as the parallel compressor. To test the new behavior, you'll need 2 good (but different) sounding Multiband 1 settings. Here's how to enable parallel compression:
- Load one of the Multiband 1 settings
- Go to Multiband 2
- Click on "Copy Multiband 1 settings to Multiband 2", under Bands (will be moved later)
- To verify that everything works as intended, enable "Parallel with Multiband 1", wait a few seconds for things to stabilize, then move the Mix slider from left to right to verify that both sound the same. (If they don't let us know, we might have missed some setting to copy)
- Load the other Multiband 1 settings
- The Mix slider can now be used to listen to each of the two multibands individually, or to find an intermediate optimal value.
Some (early - we don't have much experience with this yet) recommendations:
- It's probably good to set up both multibands such that on average, the frequency content is roughly the same. So avoid having a lot of highs in one and not in the other, for example. With similar levels, you get as close as possible to 1:2, and it makes it easier to hear which Mix value sounds best.
- Make sure that the two presets aren't too close in sound. If both make the same "mistake" at the same time, there's no benefit from having 2.
