Most mastering engineers I know give a client at the very least the opportunity to preview the kind of work they do â€“ whether thatâ€™s a single track as an example of what they intend to do or the first pass of the whole job depends on the engineer, but nonetheless, itâ€™s a pretty standard practice.
However, not everybody really knows what to listen for.Â It can be like asking someone wearing dark sunglasses what they think about the color of the curtains â€“ theyâ€™ve got a vague idea of whatâ€™s going on but arenâ€™t really sure what theyâ€™re looking at.
Overall, itâ€™s pretty subjective.Â There are a few objective criteria but most mastering engineers worth their salt will get that right regardless.Â Additionally, a mastering job can often be very subtle, so if youâ€™re not really listening for something very specific, the mastererâ€™s work might not sound terribly obvious.
Still, on a broader scope, there are things to listen for that any musician can grasp pretty intuitively:
- Is it consistent?Â Any good mastering engineer strives to make every song on an album sound like it belongs with every other song, whether thatâ€™s by loudness or EQ or overall feel.Â Sometimes, though, consistency is in the eye of the beholder.Â A compilation, for example, or even an artist that switches styles a lot, can provide a challenge â€“ what the artist (or compiler) thinks is consistent might not be the same as what the engineer (who may not have any familiarity with the genres or styles) thinks is consistent
- How are the dynamics? Despite the whole issue of the Loudness War and the pros and cons of compression and limiting, itâ€™s still pretty much a given that anything handed to an engineer is going to get at least a little compression or limiting to level things out and change the overall perceived loudness of a track.Â The overall extent of this, though, is generally left to the artists to decide, though.Â I can easily take a track up to a mean RMS of +10db (K-14) â€“ thatâ€™s very loud.Â Most artists may not want that.Â I can keep it at a mean RMS of +5db (K-14) with a very high crest factor â€“ thatâ€™s quiet and very dynamic.Â A lot of artists wonâ€™t want that either.Â Some artists, particularly in dance, WILL want a high mean RMS at the expense of dynamic range.Â Jazz artists might very well want a very low RMS and high dynamics, even at the cost of some pleasing â€œglue.â€Â A lot of it depends on the song too.Â Do you want it to sound open and airy or dense and punchy, or something else entirely?Â A mastering engineer will have opinions and generally a pretty good sense of where to go on this, just based on experience, but it can still be intensely personal (or even dependent on application).
- Does it match your goal for the sound?Â Since digital signal processing has made a lot more â€œsoundsâ€ possible than in the past, a lot of mastering engineers have a wider palette to work with â€“ without being tied to just one hardwired signal chain, they can re-route and emulate as need be (although not all of them do.Â Abbey Road, for example, has a killer mastering service and they use the same sort of bespoke gear theyâ€™ve been using for decades.Â But they have a â€œsoundâ€ all their own too).Â Â As such, the result may not actually be what youâ€™re looking for.Â I once had a mastering job that I found to be rather harsh and cold, so I gave it a very warm analog sound, as I thought fit the material â€“ but the client came back to me and said â€œwell, thatâ€™s really nice, but I was looking for this to sound abrasive and noisy.â€ Â In short, my polishing of the material was exactly the opposite of what the client wanted, and their harsh, digital sound was intentional and not just the result of their gear.Â This comes down to intuition and opinion â€“ the engineer may do what he thinks is right for the material, but that may not be what the artist intended.Â Some of this can be alleviated before the process even starts, with communication of the end goal, but as is often the case with art, these things arenâ€™t always obvious.
For the most part, what you as a client will be evaluating from your mastering engineer will be simply be how much what you get back lines up with your eventual vision.Â The engineer will have to make decisions based on how well the mix will translate across sound systems, how it will stack up on the eventual release with other tracks, and other such choices that could affect how you want the track to be perceived.Â Usually, itâ€™s a pretty transparent process of just putting the final shine on the whole album, but in the end, as the client, you have the final say.