Direct-To-Master Recording J. I. Agnew S. Steldinger Magnetic Fidelity http://www.magneticfidelity.com info@magneticfidelity.com July 31, 2016 Abstract Direct-to-Master Recording is a method of recording sound, where the music is performed entirely live and captured directly onto the master medium. This is usually done entirely in the analog domain using either magnetic tape or a phonograph disk as the recording medium. The result is an intense and realistic sonic image of the performance with an outstandig dynamic range. 1 The evolution of sound tracks can now also be edited note by note to recording technology compile a solid performance that can be altered or \improved" at will. Sound recording technology has greatly evolved This technological progress has made it pos- since the 1940's, when Direct-To-Master record- sible for far less competent musicians to make ing was not actually something special, but more a more or less competent sounding album and like one of the few options for recording music. for washed out rock stars who, if all put in the This evolution has enabled us to do things that same room at the same time, would probably would be unthinkable in those early days, such as murder each other, to make an album together. multitrack recording, which allows different in- Or, at least almost together. This ability, how- struments to be recorded at different times, and ever, comes at a certain cost. The recording pro- mixed later to create what sounds like a perfor- cess has been broken up into several stages, per- mance by many instruments at the same time. formed by different people in different environ- The advent of digital audio workstations also ments. Typically, it starts with the recording or means that apart from much greater multitrack- tracking session, where all the instruments are ing capabilities of hundreds of tracks of separate recorded, usually separately using multiple mi- recordings being layered over each other, these crophones and each microphone recorded onto 1 a separate track which can be edited and pro- recorded material. cessed individually. Then, these separate tracks go to the mixing stage where they are processed and edited even further and then mixed together 3 The digital multi-stage pro- into a coherent musical piece. This mix goes to cess the pre-mastering stage where the pre-mastering engineer processes it yet some more to optimise There are several myths regarding what exactly it for its final destination medium. Eventually, happens in the digital domain with several peo- the pre-master goes to the final mastering stage ple claiming the ability to produce infinite copies where the mastering/transfer engineer processes without losses. This only holds true when pro- it even more to successfully transfer it to the ducing identical copies of an audio file onto dif- medium, that it is going to be commercially re- ferent storage mediums, which means identical leased in (vinyl record, cassette tape, CD, etc.). copies of the same audio file onto different hard drives, USB sticks, or CD-Rs. But, it certainly does not hold true when performing signal pro- 2 The analog multi-stage pro- cessing operations, digital mixdown, format con- cess versions and A/D or D/A conversions. So in the typical digital album creation, one Aside from numerous processing units being used would start with a bunch of A/D conversions in all these stages, the recording actually has to from the analog microphone signals and related be bounced to several different mediums to be processors used during tracking into the digi- taken from one stage to the next. In the analog tal audio workstation, then apply a variety of domain, one would typically have a 2" multi- digital signal processing techniques. The multi- track tape mixed down to 1/4" or 1/2" tape, ple tracks are then sent off to the mixing stage, mastered onto 1/4" or 1/2" tape and then trans- where they might need a sample rate and quan- ferred onto a lacquer disk for vinyl records, which tisation conversion for compatibility. There they would later be plated with a thin metal film to undergo further digital signal processing and of- create the stampers, which would be used to ten D/A conversions to use outboard gear in press the vinyl records. Alternatively, the mas- the mixing studio, followed by more A/D con- ter tape could be copied onto a 1/2" or 1" tape versions to get the signal back to the digital loop, which would be copied onto 1/8" tape, that audio workstation, before performing a digital would later be loaded into cassette shells. mixdown. Next it is sent to the pre-mastering If you do the math, you will find that vinyl studio which may work at a different sample records are actually a fourth generation copy at rate and quantisation, where it would almost best, while cassette tapes are a fifth generation certainly undergo a D/A conversion to be sent copy. Each generation (copy of one tape onto an- to high quality analog signal processing units, other tape or disk) introduces losses in the form then another A/D conversion to go back to dig- of an increase of the noise floor, greater distor- ital. Next step is off to the final mastering, tion, high frequency loss, less definition and an which again probably works at a different sam- extreme decrease in the the dynamic range of the ple rate/quantisation and there, especially if you 2 want to produce vinyl records, you need yet an- daily practising with their band? The ones, who other D/A conversion and even more analog sig- will enter a studio, perform a flawless first take nal processing to protect the sensitive disk cut- of their entire album, even with the songs in the ting equipment from the high frequency noise correct order? Do musicians, who play together and other distortions created during the conver- night after night in smoke and alcohol filled base- sion processes, as well as to ensure that the ma- ments all over the world and can deliver fantastic terial has been optimised for the disk medium, performances of their songs, any time any place, which would greatly improve sound quality and really need advanced editing and signal process- compatibility with a wide range of consumer sys- ing capabilities? Especially if you add to this tems. equation the fact, that such musicians usually The less you know about what happens dur- perform on high quality instruments, that de- ing A/D or D/A conversions, format conversions, fine their unique sound, together with a care- DSP and digital mixdown processes, the better fully created acoustic environment in the stu- you will sleep at night. Especially the digital dio, there is very little, if anything at all, that mixdown could cause so many different prob- needs to be worked on. Unfortunately, there is lems, that many engineers working in the digital a common misconception, that everyone nowa- domain nowadays, prefer to perform an individ- days should do multi-track recording just be- ual D/A conversion on each track to bring them cause it can be done and can offer more flexi- down to a good old analog mixing console, and bility. But why should such musicians sacrifice do the mixing in the analog domain and record- realism and sound quality for flexibility they do ing the stereo output of the analog desk either not need? Although such musicians are getting onto analog tape or doing another A/D conver- more and more rare, very little has changed for sion to go back into the digital domain. This them through decades of advancements in mu- plethora of conversions end up doing similar and sic technology. As with any industry, in audio usually much worse things to sound as five gener- recording, the trends and developments tend to ations of analog tape copies. Not to mention the follow the masses, rather than the true talent. various problems caused by digital signal pro- cessing at low sample rates, quantisation errors during the conversion processes and dithering. 5 The Direct-To-Master Well, at least these rock stars do not need to Recording process murder each other any more and the talentless singers can explore the wonderful world of auto By removing unnecessary steps during the cre- tune to their heart's delight. ation of an album the talent of the competent musician can really shine. In the modern multi- stage process the competent and less competent 4 So, what about the talented musicians are sort of equalised to the disadvan- musicians? tage of the more competent. With Direct-To- Master Recording there is no compromise and no What about the musicians, who have spent room for errors either. The performance needs decades honing their skills and multiple hours to be perfect and the sound needs to be just like 3 how the musicians and producers want it to be, served only for the suitably talented musicians, because not much can be done later. The per- who can all be present in the recording session formers enter the room, which contains a number at the same time without any bloodshed. It can of high quality microphones, carefully selected to only be carried out by a suitably qualified engi- capture the magic of each instrument. The mu- neer who has devoted time and thought to this sicians deliver their best performance, and the process and can only be done in a purpose-built signals from the separate microphones undergo space with exceptionally high quality equipment.