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The optimum gain setting is that which allows using your computer audio software’s digital gain control
between -12 and 0 dB for critical listening sessions. The correct gain will be dependent on the overall
gain of your power amplifier plus the sensitivity of your loudspeakers.
Be careful when setting the gain switches that the settings are made
only using the switch closure
combinations listed.
Both switches must be set identically. Any other switch combinations are invalid
and will result in distortion or noise in the output.
Double check the switch positions after making any
setting changes. Then, connect the Buffer power supply and finally un-mute or turn on the power
amplifier.
Ground Bypass Jumpers
The ground jumpers may be used to bypass (in the bridging position) the 100 ohm local input ground
isolation resistor directly to common. The jumpers should normally be left in the factory (bridged) setting.
Pin 1 Output GND
Provides a direct connection between Pin 1 of the output connector and ground, bypassing a 100 ohm
resistor. The jumper should normally be left in the factory (bridged) setting.
Single Ended Jumpers
The circuit board jumpers labeled SE should be placed in the bridged position if using the supplied single
ended to balanced adapters. The factory setting is in the open position, for balanced input connections.
Note: the single ended
output
connections are derived from the balanced signal path, and are not affected
by the setting of the SE jumpers. If your input source is balanced and the output is single ended, the
jumpers should be kept in the factory (unbridged) position.
AGM Rechargeable Battery Operation and Charging
The Seta Buffer should be kept powered, to maintain both a stable circuit temperature and the condition
of the AGM battery. The idle (no signal, battery charged) power consumption is only 1 watt. If necessary,
the Seta may be disconnected from the power supply for up to a few months without adversely affecting
the battery life.
Do not store the Seta at elevated temperatures
, such as in an attic or garage.
The Seta
must
be connected to the external power supply for operation. This design insures that the
battery isn’t accidentally over-discharged, which could shorten its life. The power supply is used to
activate two normally-open relays, connecting the battery to the Seta circuitry, and the charging supply to
the battery.
Battery Life / Battery Replacement
Typical battery life will be between 3 and 6 years; up to 20 years is possible. The battery life will be
extended by keeping the Seta Buffer continuously connected to a power source (the idle power consump-
tion with a fully charged battery is less than 2 watts).
When either Battery Condition indicator illuminates with a continuous red color, and remains in that state
for an hour or more, the rechargeable batteries should be replaced.
The AGM lead/acid battery is a widely available type, commonly used for security alarm systems. The
batteries are available from McMaster-Carr (mcmaster.com), part number 7448K57. The direct factory
replacement is Power-Sonic PS-445, 4 volt, 4.5 ampere hours (AH) with dimensions (millimeters) 48 L x
53 W x 94 H with quick-disconnect 6.35 mm (0.25”) size tab terminals.
Power-Sonic website:
http://
www.power-sonic.com/ps_psg_series.php
