Sound Balancing: 3

• what a synthetic balance is
• what seperation is
• the factors affecting seperation
• other factors affecting the balanced sound
• the disadvantages of close mic. working
• the effect of frequency control
• methods of dynamic control
• what reverberation is
• how to set about creating a synthetic balance
• the different sorts of recording sessions
• advantages and disadvantages of multitrack recording.

Introduction

1. Reproducing a sound which is already internally balanced,
2. Creating a composite sound from seperate elements.

Synthetic balance

Factors affecting separation:

1. studio layout
2. microphone type (polar diagram).

Studio Layout

1. the leader or conductor must be able to see everyone,
2. musicians must be able to hear each other, (and themselves)
3. some musicians need to be able to see each other,
4. the physical position of each instrument must relate to its position in the stereo image.
5. quiet instruments or singers should not be close to loud instruments.

The layout normally adopted by the musicians for public performance might not be suitable for recording. A musician might double up on another instrument, giving separation problems if the second instrument is louder or quieter.
Undue movement of personnel should be avoided during a recording session; major reorganisation is best carried out during musicians' coffee breaks.

Microphone type

1. In proximity to an instrument the sound may be inferior, harmonics that are not normally heard at a distance may be emphasised.
2. The mechanical action of the instrument will be picked up.
3. Loud passages might overload the mic. causing distortion.
4. Movement of a musician about the microphone will have more effect on level
   and sound quality.

Close miking requires more mics, more cables, more input channels, etc. Therefore the rig is more complicated and more operator errors or equipment faults are likely.

The best separation is achieved with no microphone at all, ie. direct injection. The alternative for electronically amplified instruments is a mic. in front of the instrument's amplifier-loudspeaker.

Apart from studio layout and microphone types, other matters affecting the balance are:

1. signal treatment eg. equalisation, reverberation,
2. mixing technique,
3. recording technique.

Signal treatment

1. Frequency control, (equalisation = E.Q.)
   The emphasis or suppression of a given portion of the frequency spectrum.
   Example.
   • Presence boost (2.5 - 5.5 kHz) improves clarity of diction.
   • LF and MF boost makes strings warmer.
   • HF boost gives more "edge" to Brass.
   
   Altering the equalisation can affect the separation, e.g. if the Brass section's HF is increased overspill from the cymbals may be more evident.
2. Dynamic control,(control of sound level.)
   Dynamic control can be achieved by means of;:
   • manually moving a fader (as in recording internally balanced music),
   • a compressor / limiter in an individual channel,
   • a computerised memory system which records the levels selected in rehearsal and adjusts the channel gain as a recording progresses.

Reverberation

Reverberation can affect seperation; reflections may arrive at a mic. other than the one used to pick up the direct sound from an instrument.
Reverberation may be achieved by;

1. an echo room - a bare room with a loudspeaker at one end and a mic. at the other,
2. an echo plate or spring,
3. tape echo,
4. digital delay - a sound is broken down into its components; each component is delayed by a different amount then the components are recombined.

Mixing Technique

Here are some suggestions which might speed up the learning process:

• Adjust mic. angles to cover the width of the stereo stage (when using a Coincident Pair).
  The balance control merely shifts the centre of the image.
• Label any leads that might need to be replugged.
• Label the channel faders.
• Mix mics. in family groups (eg. rhythm, strings, brass, percussion).
• Use a group fader for each "family".
• Proceed in a logical progression to avoid confusion.
• Try to arrive at a trial balance quickly before you lose the ability to discriminate.

• the correct source
• adequate level
• good quality sound (clarity, no distortion)
• adequate seperation

• the correct amount of treatment.

Pan mono mics. to coincide with the position in the stereo image (determined by the coincident pair). Mono mics. alone could be panned to provide a stereo image but it is advantageous to use one genuine stereo channel to provide a "reference map".

When a musician is about to play the fader must obviously be open but not too wide, otherwise there will be spillage from other instruments already playing.
Reduce the fader setting when an instrument ceases, again to maintain seperation.

Apply reverberation in proportion to the amount of direct sound.

Monitor at a fairly high level so you can hear small defects but listen at lower level sometimes to see how the balance will sound at domestic listening level. This is especially important when balancing vocals with backing.
As a final check some engineers listen to the balance on a domestic quality loudspeaker (the reverse talkback speaker on some consoles is about transistor radio quality).

Make notes of control settings during rehearsal; do not trust to memory. If the producer provides a lead sheet or music score, use it to anticipate events in the performance. Make a note of any cuts (verses, choruses or sections not being performed) decided upon during rehearsal. Someone will forget a repeat or a cut, don't let it be you!

"Note and move on." This advice is as true for sound engineers as it is for performers. When you make a mistake, make a mental note of it but don't dwell on it, move on - otherwise you will mess-up the next thing you have to do ... and the next. Your first error may have gone unnoticed by everyone except yourself but, unless you put it behind you, you will pile mistake upon mistake until even the caretaker's cat knows something is amiss.

Recapitulation

The other 3 factors that also affect the balance are:

1. signal treatment
2. mixing technique,
3. recording technique.

Recording Technique

1. The recording can be treated as a live performance, starting at the beginning and carrying straight through to the end. This procedure has to be adopted at a public performance. Retakes may be possible but not too many.
2. The recording may take place as a studio session with an audience present. The situation is similar to a public performance except the producer has more control over the audience & may make more retakes. Slight imperfections are usually accepted if the performance was good overall. Significant problems are usually remedied with retakes of whole sections.
3. If the session is in a studio without an audience it is likely to be more disjointed. The producer is free to decide how the session will be run, e.g. whether to rehearse all material & then record or whether to rehearse or record in sections.
4. The recording may be multitracked. Individual sounds or groups of sounds are recorded on separate tracks of a multi-track recording machine. The 4,8,16,24 track recording is later "mixed down" to give a balanced sound. This process may take place later in a "reduction session."

Advantages of multitracking

• performers do not all need to be present at the same time
• expensive performers need not stand idle while others perform
• a performer can double up and play different parts at the same time in the final mix
• musicians who normally accompany themselves as they sing can double track & concentrate fully on one thing at a time
• complete seperation is possible eg. by recording a loud instrument on its own in the studio
• for the above reasons mutitracking is a cost effective way of recording music (and sound effects) which require synthetic balancing.
• the mutitrack recording may be retained and a completely different balance can be effected at a later date for a fraction of the cost of rebooking a recording session.

Disadvantages of multitracking

• the method is equipment intensive, i.e. requires high quality, (expensive) recording equipment.
• with analogue recorders, re-recording increases system noise, (e.g. tape hiss).

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