Bryston l14BST Bryston 14B ST Manual, Input, Balanced Vs Unbalanced, Output, Remote Power Control

BRYSTON 14B ST MANUAL

14B ST Rear Panel Connections:

Input:

The 14B ST has two inputs per channel, one for a balanced source, and one for single ended or unbalanced source. The BAL input connector will accept either a 3 pin ‘XLR’ type or a 1/4” Tip/Ring/Sleeve type. The positive (+) terminal is pin 2 on the ‘XLR’ and tip on the TRS. The input impedance is 15K ohms. The input pins are gold plated. Input sensitivity is selectable using the ‘INPUT’ slide switch. In the ‘BAL REG’ position 2 Volts in = 100 Watts at 8 ohms output. This is the recommended setting when using Bryston preamplifiers or any pre-

amplifier having active balanced outputs. This setting also produces the lowest amplifier noise floor. The ‘BAL+6dB’ setting adds 6 dB of gain to provide an input sensitivity of 1 Volt in = 100 Watts at 8 ohms output. This setting is primar- ily for balanced outputs that are transformer coupled, or other low level sources.

The ‘UNBAL’ setting selects the gold plated ‘RCA’ type tip/sleeve connector. The input im- pedance is 50K ohms. The output is in phase with the input and the sensitivity is 1 Volt in for 100 Watts into 8 ohms output.

Balanced Vs Unbalanced:

Balanced cable interconnects should be used whenever possible, as they provide common mode noise protection from external electrical interference, and with active balanced out- puts a 6 dB higher signal level flows in the ca- ble.

The unbalanced cable interconnect is pro- vided for preamplifiers without balanced out- put. Unbalanced cables should be kept to 10 feet or less. Never use longer cables than necessary, never coil excess cable length, and run signal wires away from and never parallel to A/C power or speaker cables.

Output:

Gold plated output binding posts provide dif- ferent interconnect options. Stripped bare wire up to 3 Ga. can be passed through the hole in the binding post and held in place by tightening the post knob. Additional tightening pressure can be achieved using a coin in the slots of the knob. Wire terminated with ba- nana plugs, spade lugs, or pins are also ac- commodated by the binding posts. Please ob- serve correct polarity (Red/Black) when mak- ing these connections. We recommend gold plated connectors to prevent corrosion and

signal distortion. (Bryston has gold plated 5/16 inch spade lugs available). Speaker wire should be kept as short as practical and should never be terminated with connectors that may become confused with A/C power connectors. Speaker cables should be dressed away from input and power cables, and even each other when runs are long.

Remote Power Control:

You can turn the power amplifier on/off using a 4 -12 volt A/C or D/C voltage using the 4 position screw terminal connector (see rear panel diagram page 4). Insert the 4 -12 volt wire into the input labeled ‘IN’ (polarity is not important) and then place the ‘Ext Trig’ (external trigger) switch into the ‘Rem’ (remote) position. The power amplifier will now power on and off when the control voltage is applied or removed.

The connector positions labeled ‘OUT’ can be used to power another amplifier in sequence. The 4/12 volt control voltage does not appear at the ‘OUT’ terminals until after the 14B has completely powered up so this allows se- quencing of your power amps without large turn-on surges.

WHEN THE ‘EXT TRIG’ IS IN THE ‘LOCAL’ POSITION THE 14B WILL IGNORE THE 4/12 CONTROL VOLTAGE AND WILL POWER-UP ONLY WITH THE MANUALLY ACTIVATED FRONT PANEL ‘ST’ POWER SWITCH.

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