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INTRODUCTION
Congratulations on purchasing the Fatman FAT 1 stereo valve compressor by TL Audio!
The FAT 1 is the first valve compressor to combine fully adjustable controls with fifteen
preset compression programs, allowing you the choice of creating your own unique settings
or opting for our wide selection of factory programmed presets. Now at last you have
access to professional sounding high quality valve compression for both tracking and mixing.
The FAT 1 combines classic valve techniques with solid state circuitry (known as a “hybrid”
design) in order to achieve the best combination of noise performance and valve warmth.
This makes the FAT 1 ideal for integration into both analogue and digital recording systems,
where extra warmth is required without the penalty of increased noise levels.
The block diagram of the FAT 1 is shown in Figure 1. A solid state, electronically balanced
input amplifier is used to achieve state of the art performance with very low noise, low
distortion and wide bandwidth. An ECC83/12AX7A triode valve stage (run from a
stabilised 100v DC supply) is used as a second stage voltage amplifier, to obtain the classic
valve sound and gradual overdrive characteristics.
Like all other TL Audio compressors, the
gain control element of the FAT 1 is based around a special transconductance amplifier,
which avoids the use of VCAs and helps contribute to the smooth, open sound of the unit. A
certain degree of program dependant response is built into the FAT 1, particularly for the
attack and release times, and both soft and hard knee responses are obtainable.
The FAT 1 is a stereo compressor, with a single set of controls to control both left and right
channels. The unit works in linked stereo mode at all times, whereby the control voltages of
left and right channels are linked to ensure that the same amount of gain reduction is applied
to both channels (even if one signal is below the threshold). This ensures that the stereo
image is preserved. However, the FAT 1 may be used in mono by employing the left channel
only, although the processed signal will appear on both outputs simultaneously. A single
illuminated VU meter monitors the output level or gain reduction for both channels.
Line inputs and outputs are provided on each channel, on electronically balanced jack
connectors. These are fully compatible with unbalanced signals, and the operating level of the
ins/outs can be shifted from -10dB to +4dB via a rear panel switch. A pair of front panel
instrument inputs are also provided, thus allowing guitars, basses and keyboards to feed
directly into the FAT 1, removing the need for a separate DI box.
Please read this manual fully before installing or operating the FAT 1.
