& Why You Shouldn't LIMIT OR HEAVILY Compress Your Final Mixes

I want to talk about mixing, mastering, and the relationship between the two in this lengthy article.


Specifically, I want to talk about the pros and cons (almost entirely cons) of artists, producers, and mixing engineers using (too much) dynamics processing on their master buss for their final mixes. (You could also call them “pre-masters,” but in the vinyl mastering world, a "pre-master" is actually a mastered audio file, whereas the "master" refers to the acetate disc that is cut for the vinyl pressing plant. To decrease confusion, I will be calling the files distinctively meant for a mastering engineer final mixes.)

This article is mostly for those that produce and mix their own music, and are currently or hope to in the future work with a mastering engineer. This article was read, “approved of,” and lightly contributed to, by my friend Tim Thornton, who plays music as Tiger Village and CDX. He also runs Suite 309 Records, and has been working high up in the quality control zone of a vinyl record plant for over 11 years. He has to listen to masters all day, every work day, and determine if they are good enough to be pressed.

Here's one of a few disclaimers scattered around this article: Other mastering engineers will disagree with what I’m about to say, in the sense that it doesn’t matter to them how you prepare what you send them. They probably just don't want to make the process more complicated by going back and forth with the client. For many others, the better the source material, the better the final product, therefore everyone wins. But I think that everyone winning is necessary for anyone to win in this scenario.

In this piece I am going to use a silly acronym I made up, "APM," which stands for artist/producer/mixing engineer. These titles are so not the same thing, but in the context of this article, it is safe to put them together to indicate whichever 1 or 2 or 3 of those you identify with, as long as you are the person that prints the final mixes for a mastering job.

I’m also going to use the term “master buss” which sometimes also called a mix buss, output track, 2-bus, and others. In this situation the term refers to the catch-all stereo buss in an APM's project through which everything is routed, where you’d insert processing that colors your entire mix.


Now let’s get into the nitty gritty!

There seems to be a lot of confusion out there about what mastering is, and what mastering requires of the APM.

In the DIY world, producers are used to mixing and mastering their songs themselves. In fact, many of them would not even say they master their tracks, because they know that using a little dynamics processing on their master buss is not a full mastering job, yet it gets the job done so that they can save some money and quickly publish their work.

The issues arise when the DIY world meets the professional world, where productions that are prepared with a DIY mindset are outsourced to trained engineers later on down the road. Usually this is the case when an artist gains label attention months or years after they release an album digitally, and the label wants to re-release it, often times on a physical format like vinyl.

This year, nearly 80% of the final mixes I’ve mastered for vinyl were heavily compressed and limited, AKA compromises! This is not meant to be an insult. What I mean, is that the APM either 1. did not have access to the original project files, therefore it was impossible to remove compression and limiting from their master buss before exporting their songs, or 2. did not want to remove this processing, because they preferred how it sounded in it’s then-current state, which was the way they mixed it (with a heavy dose of compression and/or limiting on the master buss).

And before you lose your hair, please know that I am more than aware that an APM using some amount of “glue” compression/coloring on their master buss is okay, normal, and preferred by many. (I do this too.) But most of what I’ll be focusing on here is compression that is used as part of the finalization process, which leaves little to no benefit in any amount of additional compression or dynamics processing of a different style or intensity in the mastering process. (More on “mix buss compression” near the end of this.)

I completely and utterly understand, so well, how important control over your sound is, as an APM! As a sound sculptor, as a composer, as a control-freak!! Plus, regardless of this professionalism and trained-ness that I am touting, your ears and your desires and your tastes may be different from mine. Some things about mastering are across the board, but the rest of it is reliant on the artist’s intention, vision, taste. In fact, a great mastering engineer is supposed to be able to correctly translate your intention, vision, and taste, into the settings on their mastering gear. Therefore, the APM needs to trust and communicate with the engineer, and the engineer needs to know how to translate what they were communicated and entrusted with into their buttons, faders, dials, and knobs.


So what I’m saying is this: You have to let the mastering engineer do their job if you are going to hire them.

In other words, you have to try your best to prepare for providing your final mixes to the mastering engineer without heavy compression, or any limiting, if that is it at all possible. (I will address the weird exceptions deeper in the article.)

Here is why.

There are processes and things I like to explore and measure, and possibly process, before the dynamics processing (compression, limiting, etc.) hits. In the event that certain moves need to be made before compression, and you’ve compressed your final mixes a bunch, you’ve painted me (and you!) into a corner. Plus, the last process on ANY and EVERY master I do, is one of potentially several stages of limiting. So you are really missing out on the quality of refinement and range of control you’d otherwise be getting had your final mixes not been brickwalled.

I would charge less for these types of jobs, but I’m still doing the same amount of work! The difference is that half of it is dialing in compromises.

Sometimes I have to master material that has been heavily compressed or limited, because that is all that exists, and these works of art gotta get refined in the best way possible given the circumstances, and be specially prepared for their intended formats! So in these situations, I always make do. I have to. Harsh noise (yes, this is a legitimate genre, that I happen to enjoy) albums in which the APM's master buss was maxed out at 0db+ the entire time in order to achieve its unique sound forces me to make do, or nothing gets pressed. The nature of mastering that kind of stuff is compromise. But here's the catch! Harsh noise LPs will suffer so much less from the compromise-oriented mastering job than music that is melodic and dynamic will.


Here are the vinyl-specific problems that arise in the case of limited or overly compressed final mixes.

You miss out on loudness. Your material will be quieter than other records. It will have to be. Which utterly defeats the purpose of you compressing and limiting your productions to be LOUD! So when trying to achieve “as loud as possible” with your final mixes, you actually get the opposite result when it comes time for pressing.

You will miss out on “cleanliness.” Your record will be more distorted, regardless of how clean the audio file is. In some situations it may be unnoticeable to some listeners, but not  the nerds, audiophiles, and musicians. Vinyl is noisy enough as it is. Your music may even be noisy.  You want your noise to be heard as clearly as possible.


You increase the risk of needle tracking issues. Vinyl does not take well to ultra compressed, ultra limited recordings. (It doesn’t take well to extremely dynamic material either…there is a balance needed! A sudden silence-to-square wave can knock the needle right out of the track.)

You will be harder on your fans’ turntables. Be nice to your fans.

Another thing worth noting is that you’re not going to put one over on the engineer doing your cutting. They’re only going to push the levels as much as they feel safe doing. Cutting too loud can do very expensive damage to a lathe, so no one’s going to risk that for you. If the master is too compressed and limited, therefore too loud, they’re going to turn it down. With a less compressed/less limited master, they have room to make the vinyl naturally clear and loud, only having to work their magic on the (hopefully far less) dynamically wonky parts. And they don't add more limiting.

Therefore, it’s best if you give me your final mixes without dynamics processing, so I can handle that part in a way that lets the cutting engineer do their job instead of calling up your label and asking them if we can provide a master with less limiting, only to be told "no" because you baked it into your final mixes. In the case of digital, cassette, or CD masters, safe but high levels of compression and limiting is fine, but best saved for your mastering engineer.

Make no mistake! I will always be able to adjust audio to be vinyl-safe (unless your band is called “Out-Of-Phase Sub-Bass Ensemble.") Just know that vinyl-safe is not the same thing as mastered for vinyl.

Removing compression and limiting from your master buss, as a producer who is new to hiring a mastering engineer, is a special kind of anxiety.

If you are concerned that you are going to lose that tight, smashed, compressed and limited sound that you worked hard to sculpt, all you have to do is communicate with the one doing the mastering. Send a demo master. Screenshots of your settings. You can even send a video of your compressor plug-in while jamming the loudest part of your songs. Explain how important it is how your transients are treated, and how loud you’d like the final product to be. Send reference tracks by artists who make similar music, who produce albums you think sound awesome. Any professional mastering engineer is going to prefer to hear this stuff from you than take shots in the dark. As long as your engineer isn’t so old-fashioned that they are afraid to make aggressive moves to get your master to really hit hard, you don’t have to worry.

And please, try your best to take care of your project files throughout the production and mixing process. I know hard drives die and files get deleted, forcing you to only have access to the most recently exported versions, but backing up your data to a cloud service is literally $6 a month through BackBlaze. Also, when you're finished producing or mixing your track, sometimes bouncing out stems and storing them on a back-up drive allows you to easily go back to them for remixing for re-releases. This is especially convenient if your old project file won't open anymore due to software updates.

I understand this instruction to not limit or heavily compress your final mixes does really get in the way of some artist’s processes, so it’s meant to be something that you do whenever possible, if possible. If this does get in your way, I highly encourage you to think of ways of making your music that do not bake these processes into your final mixes in the future, or else continue to risk limitations, complications, and compromises in the mastering process.


Now on to the subject of proper master bus compression for APMs.

There are plug-ins and hardware made specifically for mixing engineers and producers which add compression and other coloration to the mix bus. But didn’t I just lecture you about this? I can explain… most mastering engineers are okay with receiving final mixes that have been passed through a light compression, because most of the time this compression is acting as just a little glue. It can round things off, establish some cohesion and consistency, control wild fluctuations in a subtle way, give your mix some warmth. This is okay. But really, it requires that you know what you’re doing, and it requires that you don’t do too much of it. (Too much being more than a couple of decibels of gain reduction [or addition, if you're using an upward/downward process] on average).


"What about a soft clipper?" you ask. You're pushing it, kid!!! Just let me do it. I have great clippers in my arsenal.



Wrapping up.

This write-up may seem like a big subtweet to some of my best customers!! Well, it kind of is, although most of them have heard this rant before because we’ve talked about it. They are aware, but they want to put that old 2015 Bandcamp release on a triple LP set on wax because it’s a legendary album, and the original files are all lost on some old broken laptop, so of course I gladly do the job with no complaints! I just want to make it clear to potential new clients of any mastering engineer what is standard and preferred, and why. I am hoping that it will encourage APMs to take extra special care of all versions of their productions, so that these process, if used, can be removed before printing final mixes.



TL;DR: Avoid at all costs putting more than a little compression, or any limiting whatsoever, on the master buss of your pre-masters if you are having a mastering engineer work on your material. If you absolutely must compress, do so lightly, as long as it’s integral to the song’s sound, and you understand how much is too much for a mastering engineer to be able to do quality job. Communicate with your engineer so that you get the sound you’re looking for. Your engineer will communicate back what is possible based on the material provided.


Love, Angel Marcloid
Angel Hair Audio, LLC

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