cparmerlee
jpetersen
But with LANDR, what is it learning? Who is giving it feedback to say, "That sounds better, what you did this time is right"?
PRECISELY. I have some knowledge of AI systems with missile guidance. In a system like that, instruments are able to measure the target, They can provide instant feedback as to whether the "AI" maneuvers are helping to reach the target or working against that objective. Over time, such a system can "learn" what maneuvers under what circumstances are likely to be most productive.
There is no such feedback loop in this mastering thing.
Actually, there's at least one that I know of. There are three levels of intensity. I would
never use the high level but then again, I don't master Metallica

. To my ears the low level "does no harm" on pretty much anything, and the medium level may or may not work, depending on the program material. If 60% of the users choose the low one, 30% the medium one, and 10% the high one, then if the people running LANDR took that into account they would bump up the intensity of the middle one somewhat, and insert another option that splits the difference between low and medium to round out the three options.
Also, I highly doubt that no humans are involved in any aspect of LANDR. I assume they have a database of well-mastered material they use for comparison. I also suspect they do the "this call may be monitored for quality assurance" thing. If masters in particular genres are constantly being rejected, it would be foolish if a human didn't listen to them and try to analyze what doesn't work. Then they can program the algorithms to take a different path.
Here's an example. When I master, I always look for resonances that are a constant throughout a piece. This is most common with acoustic projects and live recordings due to room resonances. I then apply a notch to deal with this. If this isn't in LANDR's algorithm, and they find that acoustic and live recordings keep getting their masters rejected, someone might tell LANDR to look for resonances above a certain peak value that don't change with different notes and keys.
The article I linked to about "sonic signatures" is very much a part of understanding mastering. And, anyone who has asked for more analytics in SONAR, like being able to detect average levels, understands that many aspects of audio (note I didn't say music) CAN be quantified in the mastering stage. The human ear is much less sensitive to level variations than pitch variations, which is why something like
Pleasurize's attempts to end the "loudness wars" are commendable. They provide a measurement tool that quantifies dynamic range, and makes recommendations on what dynamic range to aim for with particular styles of music. In conjunction with understanding the "sonic signature" of different kinds of music, this is something a machine could handle easily. It could also handle looking for frequency response anomalies, like excessive buildup in the 300 - 400 Hz range, which is a common problem with many mixes.
I don't believe we're at a stage where algorithm mastering can replace a good mastering engineer, and although "never say never," I don't see that happening any time soon. But there are a lot of people out there who don't know how to master and can't afford to pay for it. Getting an acceptable mastering job is a big improvement over no mastering at all, and if they want a stellar mastering job, then can pay a couple hundred bucks for it instead of $10.
cparmerlee
I think a person could get pretty much the same results simply by adding a multi-band compressor and the Concrete Limiter to the master bus in their mix.
Not if they didn't have at least 8 stages of EQ, and probably some imaging. But that's not the point. The point is that they'll only get the same results if they know how to set the EQ, dynamics, and imaging to create an acceptable master. That's not a given. If they know how to master, then they don't need to hire a mastering engineer, nor do they need to use LANDR.
If they get the results they want with a preset from Ozone, great. But I've yet to find a preset that replaces what a mastering engineer can do; the preset doesn't know to look for resonances or frequency buildups. It seems to me that LANDR sits somewhere between calling up a preset, and calling a mastering engineer.