How To Ensure Quality Record Pressing?
Every quality record pressing starts with decent program material and at the most fundamental level it really bowls down to that. However, there are certain features peculiar only to vinyl format and a number of substantial limitations that shape and guide creative and technical decisions made in recording, mixing and mastering.
In this article I will walk you through the most essential aspects of quality assurance in vinyl record reproduction process.
CHOOSING THE MASTERING ENGINEER
Record production starts with lacquer or DMM cutting as a pivotal part in vinyl mastering process. Hence, every cutting studio is essentially a mastering studio, and engineers working with the cutting lathe are essentially vinyl mastering engineers. Most of the cutting houses use state-of-art and cutting edge mastering equipment and have plenty of knowledge and experience with the format.
It is always a clever idea to research and choose the mastering studio that runs a cutting lathe.
It is because fundamentally a master for vinyl release is not a digital file per se, it is the master plate. And your vinyl mastering engineer should be able to send freshly cut master lacquer to the pressing plant. Doing it this way eliminates an unnecessary link in the production chain and will ensure quality record pressing.
Some mastering studios welcome an attended sessions where you will hear and see how your album translates to the vinyl format in real time. Plenty of adjustments can be made at this stage to avoid issues and extra cost down the production line.
However, if you have a mastering engineer of your preference that won’t cut records, do the research and find a cutting house of your preference as well. If you decide to run cutting with the pressing plant, always get in touch with the cutting engineer.
The reason I am stressing this out is because a mastering studio that cuts actual records will always test how particular mastering approach translates on the record across given diameter.There is very little room for guessing and blind-folded decisions.
PLAYBACK TIME & SEQUENCING
Before starting a recording session for your vinyl release, plan the playback time and sequencing to inform technical decisions during recording and mixing sessions.
Principally, the standard playback time recommendations do not directly apply for vinyl records. It really depends on the program material, creative vision and fitness for purpose. Let me briefly explain.
The groove depth and width define the strength of an audio signal, stereo width and low frequency response. Hence, depending on what you are trying to achieve – more playback time implies narrowing groove depth and weakening the signal on three fronts – stereo width, low-end and output level.
Modern music that aims for a vinyl release above 18 minutes per side will be compromised to some degree. If you are working towards having 28 minutes per side, then by all means take into account reduced stereo field, slashed low frequencies and diminished output level. With low output level, background noise will be quite high and will only increase with every listening in the years to come.
Such issues as pre-echo, post-echo and skipping are also associated with narrowing the groove depth to extreme in order to fit the program material on a record side.
If a mastering/cutting engineer or a pressing plant suggest to slash the playback time or re-sequence the album – then you should follow that advise.
On the contrary, if you aim for wide stereo field, deep powerful low-end or high output level – then simply limit your playback time.
Incorrect track sequencing on a record may severely reduce the possible signal strength as well. To prevent that, sequence low intensity tracks for the inner circles and place powerful, information rich tunes in the outer diameter where there is more physical space for the grooves to wiggle.
If you decide to have one side of the record longer – make sure to remember that the signal strength for the whole record will be set accordingly to the longest side. Following industry’s best practices – recommended difference between the record sides is one minute.
Having one side 25 minutes long and another 16 minutes long will make the output signal strength severely weak for the whole release. This type of mistakes are easily avoidable.
COMPRESSION & LIMITING IN VINYL SOUND QUALITY
We all love loud and powerful records but pursuing digital loudness for your vinyl release most of the times will work against the objective. Pushing average level up to 0db with gain reduction will give you a flat, lifeless, not very loud but heavily distorted record.
Furthermore, it won’t allow recreational time for the cutting stylus, enduring significant consequences for the quality of your release. Firstly, by occupying maximum space on the record and secondly, by overheating the cutting equipment.
A cutting engineer will undertake everything to prevent damaging the equipment, to avoid distortion and other tracking issues by merely dropping the level down.
When preparing the vinyl master, leave plenty of dynamics – that is crucial for achieving great sounding record. Vinyl medium loves dynamic program material, so does a cutting lathe.
On the contrary, audio signal can always be raised to a maximum on the record at the cutting domain if there is headroom for doing so. That is an easy task since an audio signal passes through multiple hi-end gain staging equipment before it hits the cutter head.
There is absolutely no reason trying to maximize the level with heavy digital processing prior to that.
HIGH FREQUENCIES, SIBILANCE & DISTORTION
High-frequency distortion is one of the most common issues arising when program material is not sufficiently prepared for the vinyl medium. Always make sure you have high frequencies under tight control when releasing on vinyl.
There is a strict limitation on how fast the cutting stylus can move and high frequencies of 16 khz will force the cutting stylus to move 16000 times per second. That is quite a lot of pressure for the cutting equipment. Reckless mastering in this frequency range may damage the cutting stylus and at the very least will cut obscure grooves that consumer turntables will find difficulty in tracking, leaving you with a heavily distorted record.
Of course, the mastering/cutting studio may apply heavy de-essing for the whole album or a single track to help you out with distortion. But if your problem is vocal sibilance, then why not to apply de-esser in the mixing domain where vocals can be treated in isolation?
When sequencing your album, remember that inner diameter can not track properly, and the high-frequency recreation will suffer the most. It is because of awkward tone arm position and diminishing groove length per rotation.
That’s why such audio processing as de-essesing or filtering should increasingly attenuate towards the inner diameter of a record.
On another hand, the cutting stylus is most controllable in the 200Hz to 2000Hz range, which is probably the most daring for loudness, phase experiments, etc.
Finally, if you are aiming for the quality record pressing, it is always better to compose, record, mix and sequence the album in the way that won’t cause issues down the production chain. Fewer problems with test pressings will cost you less money and time, not to mention fidelity of the final pressing.
LACQUER OR DMM FOR QUALITY RECORD PRESSING?
There is a lot of incomplete and misleading information about the difference between lacquer and DMM. As a matter of fact, the vast majority of people would never be able to tell the difference just by listening to a record.
However, DMM skips one step in electroplating, hence offering lower noise floor on a record. Post and pre echo issues are also less frequent with DMM than the lacquer. Copper being hard metal is difficult to cut through, thus the vertical groove depth is shallower with DMM.
That being said, a very long album or a very quiet program material may sound better on DMM than on lacquer.
On another hand, lacquer allows deeper grooves and some program material will require that. It also sounds little softer, and some people prefer that over DMM.
Lacquer has been around for way longer and there are more engineers working with lacquer than the DMM. The majority of music ever released on vinyl was cut on lacquer as well.
Generally, both lacquer and DMM master can sound absolutely amazing if all recommendations for recording, mixing and mastering for vinyl are followed professionally.
I believe that quality of a signal chain in general, and most importantly the knowledge and experience of a cutting engineer play a way more important role in the sound quality than the material per se.
Finally, each audio recording is unique, and there is not a sensible answer to what is generally better. If you are pressing with RPM Records, please let us have a look at your music and we will recommend the most suitable method.
FITNESS FOR PURPOSE AND THE FINAL THOUGHTS
In the day and age of endless digital music distribution, you really want the vinyl edition to stand out in the light of all other mediums. There is very little rationale in offering a vinyl record at premium price that sounds worse than a relatively free streaming version on Spotify, Youtube or Itunes.
That can easily happen if you won’t take preparations for the vinyl medium seriously not only in mastering but also recording and mixing.
If your knowledge and experience with the format are limited, choose the audio engineering professionals who have plenty of experience with the medium and a track record of great sounding records. Try to master the album at the vinyl cutting studio and get engaged in the process, establish communication channels, express your vision and engineers will use everything at their disposal to help you achieving that.
Finally, if the master plates are of outstanding quality then the majority of pressing plants will be able to duplicate them in high fidelity with no considerable difficulty.
Let’s make quality records!
Quality Manager at RPM Records