Art Project Series User Manual page 4

OVERVIEW
The Tube MP/C (Preamplifier/Compressor) is a multi-purpose tool for audio engineering and recording. Enclosed
in a table-top chassis are two independent circuits featuring a tube-based analog preamplifier and a VCA-less
compressor with optical gain reduction control. Used as a mic/line preamp or as a DI (direct) box, the Tube MP/C
is designed to work seamlessly with any recording, sound-reinforcement, or electronic instrument setup. A R T's
Tube MP/C circuitry is a hybrid design utilizing the latest, most advanced, solid-state and tube technology. The
Tube MP/C maintains exceptional signal integrity and extremely low noise. A tube based opto-compressor circuit
follows the tube preamp. While the preamp is always active, the compressor may be bypassed. The
preamplifier's active balanced solid-state input provides extremely low noise and excellent CMRR. The 1/4" input
has a high impedance, which prevents the loading of any device connected to it and makes the Tube MP/C
perfect for DI or line level applications. The preamplifier's second stage 12AX7a tube runs on a regulated DC
voltage providing an additional 20dB of gain. Our design causes the tube to overload before the input or output
stage. This allows you to manipulate the tube gain to meet different sonic requirements. The compression circuit
features a VCA-less design and utilizes optical electronics (Vactrol) coupled with a 12AX7a vacuum tube gain
stage for superior musical performance. The compressor is soft knee by design. Although it is capable of
providing a thoroughly "squashed" signal in "Limit" mode, it was designed to excel in areas where transparent
and musical dynamics control is desired. The beauty of the optical/tube design is its ability to apply heavy
amounts of compression without pumping and breathing like VCA-based compressors. In many cases you will
hear the results of the compression without hearing the compressor.
SETTING UP
Unpacking
Your Tube MP/C was packed with care at the factory. The shipping carton was designed to protect it during initial
shipment. Please retain this carton for use in transporting the Tube MP/C, or in the unlikely event that you need
to return your Tube MP/C for servicing.
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