6B
SST
2
THREE CHANNEL POWER AMPLIFIER
FRONT PANEL
MAIN POWER SWITCH
The front panel label '
6B
SST
2
' is the push-button actuator to the main power switch. This is a mechanical push-ON/
push-OFF switch which activates the SoftStart circuitry to ramp up power gradually to the amplifier. Push to initiate the
power-up sequence and each channel LED will turn from unlit to red (mute). When the power supplies have stabilized
the channel will come out of mute and the LED will change to green (normal operation).
Push again and the
6B
SST
2
will power-down. ( Note: the rear circuit breaker must be on for the
6B
SST
2
to power-up)
LED INDICATORS
Each
6B
SST
2
channel has a LED indicator to monitor the following channel conditions:
UNLIT
............. Indicates channel has no power. The 6BSST channel LED when unlit indicates no A/C mains
power is present at the channel. If all channel LED indicators are unlit the 6BSST probably needs
only to be powered on. A single LED not lighting possibly indicates blown channel fuses. When
checking fuses switch off the circuit breaker on the rear panel, or unplug the power cord. Use only
the specified quick-acting 4 amp 250V 5mm x 20mm fuses
RED
(
STEADY)
..... Indicates channel is muted (power-up or power-down sequence)
RED
(FLASHING)
.. Indicates channel clipping. Clipping occurs when the channel output level no longer
can follow the level increase at the input (Over driven outeeput condition). When a 6BSST2 chan-
nel is driven into clipping the channel LED will change from green to red then back to green when
the level is reduced ( Flashing Red ). Momentary clipping can be tolerated, however it indicates
that maximum un-distorted power has been surpassed and potential speaker damage may result if
overload conditions persist. Any amplifier that is constantly operated into clipping indicates a more
powerful amplifier is needed for that application.
GREEN
............. Indicates channel operation is normal.
ORANGE
......... Indicates channel is in thermal shutdown. The
6B
SST
2
channel has thermal shutdown circuitry to
prevent damage due to overheating. Should thermal shutdown occur, the channel will mute, and
the channel LED will turn orange indicating this condition. When the channel has cooled to a safe
operating condition the channel will return to normal operation. Persistent Thermal shutdown indi-
cates steps need to be taken to increase airflow across the channel or channels heat sink. ( Also
see installation section on ventilation ).
NOTE
: In some markets the LED indicators, which are normally red/green, may be red/blue instead. When red/blue
LEDs are supplied green is replaced with blue and orange is replaced with magenta in the above descriptions.
REAR PANEL ~ INPUT/OUTPUT CONNECTIONS
INPUT SELECT SWITCH.
Each 6BSST channel gives the user the option of switching between either balanced input or single ended input.
BALANCED INPUT CONNECTOR
This input connector accepts standard ‘XLR’ or 1/4” TRS . Use quality, 100% shielded cables with
gold plated
con-
nectors.
Input impedance ≈ 20K Ohms
SINGLE ENDED INPUT
This input connector accepts standard ‘RCA’ or ‘Phono’ connectors. Use quality, 100% shielded cables with
gold
plated
connectors. Input impedance ≈ 50K Ohms
Balanced input Vs Single ended input:
The balanced input requires a balanced pre-amp source. Balanced systems provide noise protection from external
electrical interference, so cable length can be very long (50m or longer).
The single ended or unbalanced input is provided for pre-amps without balanced output. Single-ended cables should
be kept to 20’ (7m) or less. In general never use longer cables than necessary, never coil excess cable length, and
run signal wires away from AC power or speaker cables.
