It’s often suggested the audio of vinyl records sound far superior compared to their binary digital counterparts, where only the very highest end digital audio players can reach the warmth and nuances offered by a great vinyl lacquer cutting and pressing.
Sometimes people placing a vinyl order for the first time are surprised when they hear their audio back after pressing, and always in a good way. Most of the time this is due to the way the source master audio has been supplied, rather than the lacquer cutting process itself.
The lacquer cutting engineers job is to reproduce your source audio as close as possible onto vinyl, so by fixing some of the below issues at the mixing stage, you save the engineer doing these tasks, and they can concentrate on making your audio sound as best as possible on the lacquer.
There are some crucial factors that need consideration when preparing your masters for vinyl production, below we cover these points that need bearing, and the do’s and don’ts for preparing your audio for lacquer lathe cutting.
The primary rule regarding low frequencies and bass is to not supply it in a stereo format, try to convert the tracks containing bass, kick drums, synth bass and low frequencies to a mono track when you come to create your final stereo mixes.
If you’re using a stereo widener on low frequencies, then ensure this is set to above 500hz or thereabouts, and roll off frequencies below 20hz, not only does the human ear not hear below 20hz, but it helps with creating a far cleaner lacquer cut and better groove tracking.
Ensure all the low frequencies are mostly in the centre of your stereo mixes and avoid any drastic and sudden panning across the stereo plain. The sudden and drastic panning applies across the entire frequency spectrum. That is not to say do not use panning in higher frequencies, but avoid sudden and extreme sweeps from left and right and visa versa.
Likewise, try and have elements mostly located towards the centre of a mix to achieve cleaner tracking, and always listen to a mix mono. In the mono mix you may notice audio dropouts or level and phase issues that may not be evident when listening to a stereo mix, but will present issues to the engineer at the lacquer cutting stage.
Following the above low frequency and panning guidelines helps with providing a clear groove path for the needle to follow and avoids clashing grooves. It assists greatly with ensuring the music fits well in to the audio time available on the final 7″ or 12″ vinyl lacquer cut.
By centering the low frequencies one also ensures the loudest possible level in your lacquer cuts, and fixes many issues that can occur with tracking such as whooshing and ghosting; ensuring good groove geometry.
The vinyl medium does not like and overload of information in the high frequency regions. As such cutting lathes can translate an excessive level in high frequencies as distortion on the lacquer and subsequent final pressing. Remember on ta cutting lathe, treble distorts before low frequencies do.
Instruments that may contain excessive high frequency levels include hi-hats, cymbals, tambourines, high frequency special effects and sweeps. Anything above 15khz can be considered high frequency for this purpose. Not only can the frequencies lead to distortion, but can damage the head on a cutting lathe.
As a general rule any frequencies above 10khz should not be boosted in your mix. if you need more brightness or presence in a track then look at boosting frequencies in the 2.2-6.5khz range.
Finally ensure there is a low pass filter applied to the highs so any frequencies above about 18-19khz are gently rolled off and not high profile in the mix.
Sibilance is the sound of an over pronounced letter S, like a ‘SSSS’ sound. The sound can also occur with the letter T or Z. Excessive sibilance does not sound good in general and can translate to distortion when cutting a vinyl lacquer.
Vocal tracks that have sibilance should be run through a ‘de-essing’ process before final mixdown. Sibilance exists in the 58khz range, but can certainly be present at even higher frequencies.
Using a limiter on tracks is used as a means of raising the overall level, however with lacquer cutting excessive limiting can actually have the opposite affect on the audio.
Try and keep your mixes as naturally sounding as possible and without over processing at the mixing stage. The over processing can lead to distortion, and the engineer may be forced to cut the lacquer at a lower volume level to avoid distortion. This will lead to a lack of volume on the final cut, as well as a perceived higher floor noise.
With loudness do not clip your audio waveform, ie, running the audio of individual tracks into 0 decibel territory and beyond. Try an ensure plenty of space and headroom for the engineer to work in and with, this way the engineer can boost levels rather then cutting levels on frequencies that are out-of-control. Supply tracks at minus 1db, and with a average RMS loudness of about -12db.
For acoustic style albums, employ as little limiting as possible and try and ensure a natural sound in the mix, rather than over processed. The engineer is then able to boost the overall level going to the lathe rather than fighting with distortion issues inherent with limitation and compression.
When listening to vinyl records you may notice that the quieter ballad or instrumental style tracks are often nearer the centre or at the ends of each side. The reason for this is the lathe head cuts slightly quieter as it get closer to the inner grooves and the needle does not travel as fast on the outer grooves, therefore the clarity at the top end is not the same as on the outer tracks where the needle is moving at a faster speed, (it’s the same principle for why 45’s sound better then 33’s). (You may want to add a little tiny whiny slight boost to the high end for those last one or two tracks on each side of an LP).
45rpm 9 mins per side
33rpm 1519 mins per side
45rpm 4mins per side
33rpm 6 mins per side
Excessive Highs: The engineer may need to run a low pass filter, therefore affect every frequency above a certain range.
Stereo Low Frequencies: Depending on the frequency range, the engineer will run a low cut filter in order to control lower frequencies. Again as this run on the stereo mix, the filter cannot differentiate between problematic low frequencies, and those low frequencies, which are fine, therefore reducing all of them.
Sibilance: High levels of sibilance will trigger the de-esser filter. The de-esser filters are in the 5-8khz range, and therefore rather then only de-essing the vocal tracks, everything in that frequency range will be changed.
The lacquer cutting engineers job is to cut as flat as possible in order to try and match as closely as possible the provided master audio.
It is therefore very important that sonic adjustments to the audio are made at the audio mixing and mastering stage rather than the lacquer cutting stage, this way the audio engineer can concentrate of reproducing as the original, and look to enhance the sound through enhanced warmth and natural sounding loudness level.
Equalisation adjustments carried out at the cutting stage are macro adjustments that affect the entire audio master rather then just on individual audio elements which can be controlled through separate equalisation at the mixing stage.
Any music that pushes any of the above-described audio boundaries, then the problem is likely to be magnified and exaggerated at the lacquer cutting stage when compared to the digital masters.
For the above reasons a record which has been professionally cut may not sound like the digital masters that are supplied. If you have any concerns about your audio and how it will translate at the lacquer cutting stage, it is important to have your audio checked with a vinyl-mastering engineer.
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