Pre-mastering for Vinyl

When finalizing audio projects that are going to be released on both digital and vinyl, those of us that work with the digital files are technically pre-mastering for vinyl, since the actual master for this format is the lacquer. From the lacquer master, stampers are made and those are then used to stamp the actual records that we play.

It’s common to hear that the same masters used for digital distribution are also used for the vinyl release. About half of my clients who release their projects on both use the same files, but the other half prefers to have a different set of masters, one that is a bit more dynamic for that format and while I’ve been doing that for quite a few years now, I never thought that some consumers might be interested in knowing when a sonically different set of masters is used for the vinyl release.
Recently, while browsing a vinyl collectors forum, I came across a post where someone asked if there was a way of knowing which vinyl releases used different masters, ones that are not as compressed and limited for loudness as the digital release. Some people assumed that they would be different by default, thinking that just because it’s on vinyl that the audio will be more dynamic; a few people mistakenly think that every time a vinyl record is made, an in-house mastering engineer automatically works with the files to make sure they’re optimal before the records are made. This doesn’t always happen, every vinyl record pressing plant approaches this differently.
Some pressing plants have in-house mastering engineers who will master the tracks, paying attention to low end phase issues, and excessive high end frequencies that would sound distorted on vinyl. These pre-mastering services are typically added on top of the vinyl production costs, or offered as an additional service for clients that are not already delivering optimized audio files ready to be cut. Pressing plants that do not have in-house engineers refer their clients to mastering engineers that specialize in mastering vinyl projects, who could then send pre-mastered files, or make the lacquer themselves and send it directly to the pressing plant for cutting. Most, if not all of the vinyl pressing plants will take the files you send in (even if they are heavily compressed and limited) and make the records, as long as you approve the test pressings. Many also accept CDs as a source and also offer tips and guidelines. One of the suggestions is to avoid things such as too much compression and limiting.

It can be difficult for consumers to know if the pre-masters for vinyl have been optimized, or if they’re the same files that were mastered for digital distribution.

Some people have digitized their records and have compared the vinyl tracks to the digital release. On some vinyl releases where the same digital masters were used, a few people reported that the vinyl “rip” sounds slightly flatter and not as defined as the digital version. To be fair, this can happen due to several issues, starting with the actual quality of the vinyl lacquer master and the overall quality of the record itself, less than great ADC conversion from the vinyl chain, and other issues related to the playback system like poorly-designed phono preamps, cabling, the cartridge, needle and even the turntable itself. Hum can also be a factor, it’s a common issue with unbalanced (RCA) stereo connections.
The truth is, digital has more headroom than vinyl. The vinyl format is not superior in the sense that it promises more sonic “real estate” and a better signal-to-noise ratio than digital, it’s actually quite the opposite. The limitations of vinyl are what makes it appealing and I believe that when pre-mastering for this format, we can use these limitations to our advantage.
I think it’s possible that when some people say vinyl sounds better than digital, they’re comparing an original record that was made before the digital age, and comparing its sound to a “digitally remastered” version that they might have bought on CD, or streamed over services like Spotify. I can think of a few older LPs that I own that sound a bit more open and dynamic when compared to the remastered version on digital. Compression and Limiting is necessary to a degree for digital mastering, since a lot of people listen to audio on under-powered devices like mobile phones. You don’t have this issue when playing back vinyl. Integrated amplifiers and receivers have plenty of power to drive speakers and it’s typical to adjust the volume on every record that you play. Realizing this allows us to be able to create pre-masters that are a bit less limited/maximized and more dynamic than the digital version. When done right, these records remind me of classic Hip Hop releases from the 90’s.
So how do I approach it? First, I’ll work on the digital versions and after getting the approval from my clients, I’ll proceed to work on the pre-masters for vinyl, since the idea is to keep the sonic quality as close as possible to the digital release. These are delivered to the clients at their native resolution (24 bit, and whatever sample rate the mixes came in).
I listen to the mixes in mono to make sure there aren’t any phase cancellations. Sometimes at the production and mixing stage, stereo widening processes are used and these are fine for digital, but they can cause phasing issues for vinyl so if that’s the case and some of the low end is disappearing when checking mono, I’ll create a mid/side matrix on my DAW and adjust the mid channel, or perhaps bring down the sides a bit. Breaking the stereo mix apart into its mid/sides also allows the possibility to use processors independently over them, and so I’m able to treat issues that might be a problem on the sides independently of the mid or vice versa. There is no use of limiters or maximizers, and the master output level on these mixes is reduced to peak just below full-scale.

If you already have dynamic masters for digital, it’s fine to send those out to the pressing plant, but why not give your listeners a slightly more dynamic version of your album on wax?

When doing an additional set of pre-masters for vinyl, I’m now also sending my clients a high resolution version of the graphic at the top of this post that they could use on their vinyl cover art should they wish to do so, indicating to those who purchase the records that they’re going to be experiencing the release in an optimized way for that format. This might also prompt some of the people that enter information about these releases on sites like Discogs to note when a vinyl release was made with optimized pre-masters for the format (thank you whoever you people are, by the way).
When done right (and you’ll have to trust your ears to know when it’s right), those listening to the vinyl versions should be able to tell that it sounds a little different than the digital release, but in a way that works well for this format. Maybe they’ll hear the drums cutting through their speakers with a little bit more punch and hear the tracks “breathe” a bit more too (because there will be more dynamic range and a higher crest factor). Artists could even offer the vinyl pre-masters as high resolution downloads with their vinyl release; there’s a growing demand for hi-res Hip Hop from audiophiles, but that’s going to be the subject for another post. Thanks for reading!