Wednesday, 2 January 2013

Digital vs Analogue – Finding the Balance

From Firebrand Magazine Issue #3, December 2012

Some interesting and valid points have been raised over the years regarding the somewhat 'sterile' sound of a lot of today's modern recordings. The advent of digital equipment has removed a lot of the bugbears of the recording process, while introducing a few unique problems of its own.

First of all, we should consider the human ear, which is far from perfect in its design and function - I mean, if Darwin is right, they may have been gills at one stage. Our perception of sound is quite limited in comparison to that of some creatures further down the food chain. However, they're all we've got to hear with, so I shan't go on about it. The loudspeaker is another relatively inefficient mode of conducting sound which has yet to be improved upon.

The first thing we noticed about compact discs, upon the advent of the technology, was the absence of extraneous noise on our recordings, such as tape hiss and the crackling of a stylus scraping around on a piece of vinyl. This was hailed as a great breakthrough in music technology, and indeed it was... there was, however, a down side to this new 'clean' sound, namely a lack of warmth that could be easily be translated as sounding 'sterile' or mechanical.

There is a certain personality to older analogue recordings that is sadly missing from a lot of today's music, although it is not all because of the digital recording age. When the techno dance craze hit, the majority of this style of music (using the term loosely) was created using sequencers and computers, thus eliminating the human factor. To the trained ear, there is a vast difference between a musician playing a part and the same part being generated by a piece of electronic equipment. In musical parlance, this indefinable human 'something' is called feel. There are drummers out there who can play as perfectly in time as any drum machine (Steve Gadd comes to mind), but can alter the beat imperceptibly so as to create feel and mood within a rhythm. The same applies to other instrumentalists who can create a mood or a feeling with subtle inflections of melody or groove.

The same technological overkill that affected the creation of sounds also affected the way that those sounds were recorded. There is a very important factor that is removed when you plug a box straight into a mixing console and hit 'record' - the movement of air. Sound waves create pressure on our eardrums, which then send information to our brain. The brain makes sense of this data, and tells us what it is we are hearing, and at what volume. Loud noise or music puts more pressure on the eardrum, hence the term Sound Pressure Level (SPL), which is a fancy way of saying 'volume'.

Normally, when we listen to something, we are not only hearing the sound from the source itself, but the sound reflecting off objects in our immediate surroundings and eventually finding its way to our ears. This, of course, is what happens when we hear an echo. Another factor involved in our normal perception of sound is that we very seldom hear just one thing - there is always background noise, be it obvious or subliminal. This background noise creates 'colour' in our perception of sound, and it is this subtle absence of background colour that can create the sterile sound mentioned earlier. Sir George Martin, one of the greatest record producers of our time, is reputed to have included tracks of random noise (people talking, doors closing, street noise) on some of his later recordings, placed way back in the mix, just to add warmth and colour. You couldn't hear it, but the effect was to retain a human, organic element in what had become an almost impersonal recording procedure.

While this latter day obsession with 'clean' has wound up sacrificing some soul in the process, recording digitally does not necessarily mean that the result is going to sound soulless and sterile. Now that the craze for all things new and overly clinical has settled down somewhat, a lot of studios and producers are returning to some of the old equipment, such as valve amplifiers, equalizers and compressors. These pieces of gear have a little more warmth than their solid-state counterparts, and help to retain a bit of personality in a recorded sound. The beauty of recording in the digital domain is that 'non-musical' noise is no longer a problem. The art of recording now is to create 'air' and 'movement' in the sound of a recording, so as to retain a little humanity in the music. This can be achieved with all our new toys and gadgets, but having said that, it is easier said than done. That is why the top producers and engineers get paid so much money!

There is a factor in recording that continues to be a point of contention amongst the audio community – compression. Compression is used in audio recording to limit the transient peaks in a piece of music so as not to damage precious equipment or hearing. It also boosts lower levels in the same recording to achieve a more even response and add perceived loudness to a track. A problem arises when a track is compressed too much, making it sound loud, but without any dynamics. Television and radio stations compress their audio signals to keep all their broadcasts within a specific dynamic range. A trick they often use is to compress their advertisements more heavily, making the sound of the ads jump out and catch the attention of the listener/viewer. This why the volume of TV commercials seems to jump up (sometimes annoyingly) from the level of the actual program we are watching. This marketing ploy has enraged many viewers who have to turn down the volume on their TV when the ads come on because the volume becomes uncomfortable, especially if they are watching a show with the sound up fairly high. It is only recently that legislation has been introduced in some countries to address this discrepancy.

In music recordings, many bands will have their material mastered with a high rate of compression, believing that it will make their music ‘jump out’ from the other offerings on the same program or channel. This practice has led to what has become known as ‘compression wars’, where entire albums are produced at a compression level that seems always on the verge of ‘clipping’, or passing the threshold of distortion. This threshold is a little bit different between digital and analogue recordings – pushing an analogue sound can result in added warmth, whereas with digital, once you cross the line, you’re in digital distortion land, where the high frequencies become harsh and unpleasant. The thing that most of these audio ‘rev heads’ seem to forget is that when a piece of music is broadcast, it is compressed by the people doing the broadcasting, so too much compression at the recording stage is only going to make a track sound squashed and small when broadcast – not the optimum result if you want your band to sound bigger than Ben Hur in the marketplace. 

One of the worst results of all this over compression is that a piece of music will become devoid of dynamics – the areas of low versus high intensity – and lacking in that all-important ‘feel’ that gives a song personality. This is particularly true of rock and metal acts that want to have everything louder than everything else. Volume does not always equal power and impact, and there are some very wimpy sounding metal recordings out there as a result of uninformed musicians turning everything up too far. While there are thousands of pieces of gear that will enhance and effect sounds, the best rule of thumb is still “does it sound good?” This applies to digital and analogue recordings, and always will. There are also thousands of digital plug ins and add ons that can emulate analogue equipment. If the new digital sound was so much better, I doubt if there would be so much emulation going on. When it comes down to it, beauty is in the ear of the beholder – a good sound will still be a good sound, and a good song will still be a good song. If you have a good enough command of digital technology, you will be able to produce a clear, warm and dynamic recording on ProTools or Logic. When it comes to making memorable music, it still – and always will – come down to the Artisan, not his tools.

Graham Greene

Read the rest of Issue #3 here.