3
ST
™
2 – SMARTUBE
™
MICROPHONE PREAMPLIFIER
OWNER’S MANUAL
DESCRIPTION:
ST2 is a two-channel, single rack space voice processor – channel strip. It is designed for direct
recording with special attention to the logical signal-flow layout and added features. The main
purpose is to get the signal from the input audio source to the recorder as clean and directly as
possible. Each of the two channels consists of four functional sections: microphone and line
preamplifier, 4-band parametric equalizer, output level/pan/meter/sum, and tube-sound processor.
The number of ins, outs and insertion points allow each of these sections to be used separately or in
conjunction with the others. With its versatility, comprehensive features set and expandability, the
ST2 is intended to be used for tracking and mix down in recording studios, as well as live
performance applications.
Each of the two channels has an XLR low-impedance microphone and a high-impedance 1/4"
line/instrument(DI) input with jacks conveniently located on the front panel and duplicated on the
rear panel. Both inputs have separate gain controls. The Mic input has a –20 dB pad; phase-reverse
(polarity); a +48 V phantom power switch with LED; and a switchable, forth-order high-pass filter. An
Insert Unbalanced I/O with separate 1/4" Send and Return jacks is provided on the back panel.
Equalization consists of a shelving Low and High section and two fully adjustable Low-Mid and High-
Mid parametric filters. There is a Level, Pan and tube-sound blend control with bicolor LED,
Mono/Stereo, Sizzle and Mute (with LED) switches and post-Level, pre-Pan unbalanced direct
output. Metering comprises of a 10-segment multiple color LED bar-graph array that indicates the
level on the direct output and a separate signal-presence LED.
The two channels can also be assigned independently to either A/B stereo bus or only A or B bus
via the Stereo/Mono switch. In Stereo position the Channel 1 signal is panned between A and B bus.
In Mono position the Channel 1 signal is sent only to A bus, bypassing the Pan pot. In Stereo
position the Channel 2 signal is panned between A and B bus. In Mono position the Channel 2
signal is sent only to B bus, bypassing the Pan pot. Unbalanced (0 dBu 1/4") and balanced (+4 dBu
XLR) outputs are provided on each of A and B summing buses. A pair of additional, balanced (+4
dBu 1/4") I/Os enable the expansion capabilities of the ST2. Several units can be daisy-chained,
each next becoming a master for the preceding ones.
ST2 has a built-in power supply and the line connection is through an IEC connector on the back
panel. A master power switch with on/off LED indicator is located front-panel right.
