For the past few years there has been a debate between fans of digital and analogue technology. Much of the debate has been based on a lack of information, or even on disinformation by manufacturers wishing to push their pet technologies.
For a long time, it looked as if the digital camp was having things all its own way. Cheap and cheerful digital desks and recorders seemed to be the magic answer to everything. They claimed to be almost noise and distortion free and far easier to operate than the old analogue desks and tape machines.
These claims were, of course, false. The desks were bewilderingly complicated and the tape machines lost sync, broke down and chewed tape. The first attempts at hard disc recorders in PCs and Macs were of poor quality and very unreliable. The slow 16-bit converters caused hums and buzzes as they interfered with the very audio signal they were trying to convert. As the track numbers increased, the machines got slower and slower, until they went into a coma and the audio was lost completely.
The professional answer to these absurd systems was to upgrade analogue. Desks became quieter, tape became thinner and had better HF (high frequency) response, dynamic processors became faster and Dolby SR noise reduction was born.
But the writing was on the wall. The professional was recording onto analogue tape, but the consumer was listening to 16-bit digital CDs and the race was on to create a new digital multitrack system. The first systems were 16-bit and sampling errors and noise floors, when added together over 24 or more tracks, were not good enough. But 16-bit was good enough for amateur recordings and soon the eight-track ADAT machine was hailed as the answer for amateur home recording. Over the years some 150,000 ADAT machines have been sold, despite all the problems of chewed tape, poor quality and lost sync signals.
The professional standard was DASH (Digital Audio Stationary Head) built by Sony. At first acceptance was slow as this too was just 16-bit and used expensive and unreliable tape. The first machines were just 24-track, but soon a 24-bit, 48-track version became the professional studio standard. These machines were expensive and required considerable maintenance, but set a whole new standard in audio quality.
Unfortunately many people compared first class analogue tape with Dolby SR to 16-bit digital recorded on amateur ADAT machines using poor converters and claimed that digital was poor and 'unmusical.' The analogue to digital (AD) converters in amateur equipment lack headroom and fall over immediately into total distortion if the input signal is too high. The machines are very unreliable and the resolution is poor. Comparing professional analogue to amateur digital is like comparing a vintage Ferrari with a new Ford Fiesta.
Today there are still many manufacturers who claim to give you 'a complete professional recording studio right on your own desktop!' These claims fall down very quickly when such systems are asked to perform everyday tasks like recording twelve drum tracks at once or mixing 36 tracks down to a master.
But there are two professional hard disc recording systems that are found in every professional studio: ProTools and Radar. ProTools runs on Apple Mac and is usually equipped with eight inputs and can perform just about any post production task you can think of. It was originally used as an audio aid for Avid video suites, but soon found acceptance as a home studio system. Later many studios realised the advantages of desktop editing.
Radar targeted professional studios right from the outset. It has either 24 or 48 inputs and works just like a tape recorder. Tracks are armed in the conventional manner and the only differences are that one can cut and paste, rewinds can be performed instantly and the quality is far higher than any conventional tape recorder could achieve.
If effects are nearly all digital and recorders are digital, why do professional music studios put large and expensive analogue mixing desks into the heart of their operations?
The answer is, when you are track-laying music (as opposed to video post production, for example) digital desks do not work - and they do not work for two reasons: latency and ergonomics.
Latency: An AD converter takes time to sample a piece of audio and convert it into a block of zeroes and ones. The very fastest take just five milliseconds (5ms), slow audio cards in PCs can take 50ms or even more. A millisecond is a thousandth of a second, so these times do not sound like much. But the human ear uses time to hear in stereo and we can hear the difference in the direction of a sound down to just five degrees. That is a time difference of 18th of a millisecond! Real stereo becomes impossible and long latency times (25ms or more) destroy the timing and feel of a piece of music.
Professional digital recorders do not suffer from this because they run off an internal clock that aligns the tracks perfectly.
Ergonomics: This is a fancy word for ease of use of equipment. Analogue mixing desks have always had the same basic layout: a series of buttons and knobs at the top of each channel for routing and volume control of inputs and outputs to effects and tape machines, then there is an equalizer to alter highs, mids and lows and at the bottom there are pan pots (for left to right and/or front to back) and a master fader. There may be other controls for tape inputs and dynamics such as gates and compressors, but basically that is it.
That means that any experienced technician can work on any desk after a short learning period and bands and orchestras can use their favourite engineer and do not have to rely on some stranger who may, or may not know what they want.
Digital desks are very different. Knobs have to be assigned a function and channel strips are very often scrolled from left to right to keep down the size and cost of the desk. Behind each channel is a menu of functions and routing possibilities that have to be called up from a central computer. If you want to turn down the highs on channel 24, you must choose channel 24 on the central computer, scroll down to the EQ section and select the low-pass shelving filter and either assign it to a knob on the desk or type in a new value. If you decide to tweak it again later on, you must go through the whole procedure all over again.
Digital desks are great for video post production because the same person has to perform the same tasks over and over again and the more advanced models provide tools for automating repetitive tasks. But in music recording, they just provide new opportunities for confusion, frustration and time wasting.