Bryston BP25, BP20 Phono Equalization Modules Optional, Digital Audio Input Module Optional

BP20/25 PreAmplifiers

PHONO EQUALIZATION MODULES (Optional):

Bryston’s phono equalizer circuitry is available in both BP20 and BP25 pre-amplifiers. It features highly accurate equal- ization, extremely low noise and distortion and provides headroom margins sufficient to prevent overload from any known phono source. If your turntable provides a separate ground lead , system noise may be minimized by connect- ing it to the ground post adjacent to the phono inputs on the rear panel.

Moving Magnet Phono Cartridge Input (MM):

This is Bryston’s standard RIAA phono equalization stage. It is found in both the “-P” and “-MC” versions of the BP20/25 pre-amp. Input impedance is 50K ohms and sensitivity is 5mV.

Moving Coil Phono Cartridge Input (MC):

Moving coil phono cartridges require much more gain than the more common moving magnet types. To accommodate moving coil cartridges Bryston offers the BP20MC/BP25MC pre-amps which include specially designed, custom made step-up transformers in addition to Bryston’s standard RIAA phono equalization stage found in the “-P” versions of the BP20/25 pre-amp. Which phono equalization stages are engaged is determined by the front panel toggle switch labeled “MC Phono / MM Phono”. This switch is not present on the BP20P/BP25P models; it is replaced, instead with a “Mono / Stereo” switch. Please note that it is important that your phono cartridge is connected to the correct inputs in order to achieve proper performance.

Input impedance is 180 ohms and sensitivity is 350uV.

DIGITAL AUDIO INPUT MODULE (Optional):

The BP20DA / BP25DA models contain two SPDIF com- patible digital audio inputs. To select either the DAC-1 or DAC-2 digital audio input, first set the rotary SOURCE selector to DAC, and then select between the two SPDIF inputs with the DAC-1/ DAC-2 toggle switch. The digital-to- analog convertor can handle input sample rates from 16KHz to 108KHz, and word lengths of 16, 18, 20 or 24 bits.

VISUAL INDICATORS:

MPS1 Power Supply: The LED on the front panel of the MPS1 lights GREEN when power is on and RED when the power is on but the main outputs are muted by having acti- vated either the “Mute/Normal” toggle switch (on the pre- amp’s front panel) or the “MUTE” button on the hand held remote control.

BP20/25: The three colour LED (light emitting diode) located on the front panel lights RED when the output is muted, GREEN when the output signal is non-inverting polarity and YELLOW when the output signal is inverted with respect to the input. When the LED is unlighted, the power is off.

FRONT PANEL CONTROLS:

MUTE/NORMAL TOGGLE SWITCH: Mutes or releases mute at the main outputs, (not ‘To Tape’ outputs), without changing the volume control setting, each time pushed.

POLARITY/INVERT TOGGLE SWITCH: Reverses polari- ty at main output5 each time pushed. (GREEN LED indi- cates positive polarity, YELLOW LED indicates inverse polarity).

VOLUME CONTROL: Rotary control varies the output level to the ‘MAIN OUTPUTS’, (does not effect ‘TO TAPE’ outputs). BALANCE: Rotary control adjusts the left-versus- right channel levels.

BALANCE CONTROL: is a tailored-inflection type which has very gradual action near the center of rotation allow- ing fine adjustments to the stereo image. For convenience the electrical center of the control is detented.

SOURCE SELECT SWITCH: Rotary switch determines which input will appear at the “TO TAPE” outputs for recording or processing, as well as determining which pro- gram is available at the Main outputs. (When the “TAPE/SOURCE” switch is in “Tape” position, “FROM TAPE” inputs appear at Main Outputs).

MONO/STEREO SWITCH: “Stereo” position provides two-channel stereo at the Main outputs. ‘Mono’ position sums the main outputs to monaural. The ‘TO TAPE’ out- puts are always stereo. (Switch not present on “-MC” or “- DA” models).

MC/MM PHONO SWITCH: This switch is present on the BP20MC & BP25MC models only. It allows the selection of either Moving-Magnet or Moving-Coil phono equaliza- tion. This switch takes the place of the “Mono/Stereo” tog- gle switch on other BP20/25 models.

DAC-1/DAC-2 TOGGLE SWITCH: Only on BP20DA & BP25DA models, this switch determines which of the two SPDIF digital audio inputs is processed and then sent to the tape and main outputs. The SOURCE select switch must also be in the “DAC” position to monitor the digital audio inputs.

TAPE/SOURCE SWITCH: “Source” position monitors whichever input is selected at the rotary SOURCE selector rotary switch. “Tape” position provides monitoring of the “FROM TAPE” input for A/B comparison with the source. Should an external processor or equalizer be connected in the tape loop, the ‘TAPE / SOURCE” switch will act as an in/out switch for the external equipment.

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