The Forssell Technologies Inc SMP-2A is a 2 channel, transformerless, Class A discrete JFET
microphone preamplifier housed in a single space rack chassis. Each channel on the SMP-2A
has front panel mounted controls for gain, output muting, polarity reverse, and phantom power
on/off. The mute, polarity, and phantom power switches each have LED indicators which
illuminate when the switch is pressed in to indicate that the switch is on. The gain control is
variable from minimum to maximum gain in 24 stepped positions. Bicolor LED level indicators
are also present for each channel. These LED indicators show green with the output signal level
is above –5 dBu, and red when the signal level reaches +24 dBu, which is 2-3 dB prior to
clipping. A power on/off switch and LED are also located on the front panel.
The rear panel contains the two input and one output XLR connectors per channel. All XLR
connectors are wired Pin #2 hot. There is an input XLR for phantom powered mics (labeled
P48), and one for non-phantom powered mics (DC) such as ribbon, dynamic, or externally
powered condenser mics. There is also an IEC AC power connector and fuse holder on the back
panel. The fuse holder is integrated into the IEC power connector and uses 5x25mm slow blow
fuses. There is a spare fuse located within the fuse holder. The fuse type is 250 ma time-delay
or time-lag fuse. If your preamp is wired for 230 VAC, then please use a 100 ma time-delay
fuse.
An AC line voltage switch is located inside of the SMP-2A. Please refer the SMP-2A to a
qualified technician to change the line voltage setting.