TL Audio Fat Track - Manual (Page 13)

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contact with microphone stands or microphone cables. Popping is an undesirable
thump that is caused by close-miking certain spoken or sung letters, namely 'P' or 'B'.
These particular letters cause a sudden expulsion of air that can result in an audible
thump. As this thump has a lot of low frequency content the high pass filter can help
to reduce the problem, as can using a pop filter (a device usually made out of nylon
material similar to stockings) suspended in front of the microphone. The low cut filter
is easily bypassed for quick A/B comparison.
30dB Pad
Occasionally when using sensitive condenser microphones the source signal may be
too loud for the input preamp. In this situation, to avoid any overloading or distortion
of the mic preamp stage, the 30dB pad can be used to reduce the input gain to a more
manageable level. The 30dB pad only applies to the microphone input.
Equalisation
Before switching the EQ into circuit, it is advisable to set the cut/boost controls to
their centre, or flat, position. The EQ is brought into circuit with the 'EQ ON' push
switch, located at the top of the channel strip. Each channel has three bands of
equalisation:
1/. shelving wide band low frequency (LF) (i.e. it extends from 80Hz to the extreme
low frequency limit of the equaliser's response.),
2/. peaking
sweepable mid (i.e. it boosts or cuts a section of the audio spectrum around
its selected centre frequency only)
3/. shelving wide band high frequency from 12 kHz to the extreme high frequency
limit of the equaliser’ response (HF).
The LF shelf operates at a frequency of 80Hz, while the HF shelf is set at 12kHz. The
EQ slopes have a second order 12dB/octave response, and an associated gain control
on both bands provides up to 15dB of cut or boost on each selected frequency,
controlling the full range of frequencies below the LF corner frequency and above the
HF corner frequency. The mid band has a fixed Q of 0.7 allowing +/- 15dB cut or
boost over a moderately broad band of frequencies. The centre frequency is selected
via the dedicated variable frequency control, and the required amount of cut or boost is
applied using the associated gain control. The range of frequencies selectable is 150Hz
to 7kHz.
When listening to a mix, it is generally frequencies between around 40Hz and 12-
14kHz that the ear is most sensitive to and a distinct lack of any one frequency in
between these figures can result in a mix that may lack ‘fullness’. Generally, a
pleasant mix will contain a good balance of frequencies from across the spectrum.
Each part of the frequency spectrum does however contribute its own unique
characteristic. For instance, if there is too much low frequency content below around
300Hz, the mix can sound ‘boomy’ or ‘muddy’. Too little presence from these
frequencies however and the mix can sound ‘thin’ and lacking ‘power’ or ‘energy’.