Introduction
Thank you for your purchase of a Furman IT-1 220 20 Amp Balanced Isolation
Transformer, and congratulations on your choice. This specially wound and
shielded toroidal isolation transformer is designed specifically to reduce hum
pickup by sensitive equipment when ultra-low-noise is a must.
Features
•
Provides precisely balanced AC power for ultra-low-noise installations
•
Typically gives a 16 dB improvement in background noise floor in system wide
installations
•
Toroidal transformer with center-tapped secondary is the most efficient,
compact design, with least magnetic field leakage
•
Soft Start circuit prevents turn-on transients and high inrush currents
•
Faraday shield reduces electrostatic coupling between primary and secondary
•
Extreme Voltage Shutdown circuit protects against dangerously high or low
input voltages
•
Microprocessor-controlled "smart" AC voltmeter monitors line voltage, flashes
alerts for marginal and extreme conditions
•
Provides basic power conditioning functions (spike suppression, RFI filtering)
•
Ground fault interrupter (GFCI) protection
Description
Designed for the most critical, ultra-low-noise installations, the IT-1220 can
supply 20 amps of
balanced
AC power to a recording studio, video or film
production facility, broadcast station, etc. Its purpose is to drastically reduce hum
and buzz caused both by ground currents from power supply filtering and by
radiation from supply cables into sensitive signal sources like guitar pickups and
microphones. Its effect is startling! It not only dramatically reduces the noise floor
but also noticeably improves dynamic range and sonic clarity. The IT-1220's
heart is a specially wound and shielded toroidal isolation transformer with a
center-tapped secondary. It is housed in a 3-unit (5.25" high) rack mount chassis.
The back panel provides 12 balanced outlets, widely spaced 'with plenty of
clearance for "wall warts"; the front panel provides two more. An IT-1220 can be
installed in minutes without need for an electrician. It provides clean and
completely safe power-there is no need to "lift grounds" or compromise the
integrity of safety ground wires to achieve hum reduction. Special features
include an accurate, self-checking AC voltmeter that not only measures normal
voltages, but also flashes eye-catching special pattern alerts for off-scale but not
extreme conditions (80-90 or 130-140 volts); an Extreme Voltage Shutdown
circuit to cause a protective shutdown if the unit is exposed to dangerous
voltages (like accidental connection to 220V); and a special "Soft Start" circuit to
prevent the large inrush surge currents and spikes that would otherwise occur at
turn-on and turn-off with such a large transformer.
