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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Bryston BP25, BP20 owner manual Phono Equalization Modules Optional, Digital Audio Input Module Optional, Visual Indicators
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BP20, BP25 specifications

The Bryston BP25 and BP20 represent a pinnacle of engineering in the world of high-performance audio preamplifiers. Renowned for their exceptional sound quality and meticulous design, both models are integral components for audiophiles seeking unparalleled audio fidelity.

The Bryston BP25, with its robust construction and audiophile-grade components, delivers a highly transparent audio signal that preserves the integrity of the original recording. One of the standout features of the BP25 is its fully balanced differential design, which helps to minimize noise and distortion. This topology results in a cleaner, more detailed sound, making it an ideal choice for critical listening environments.

Equipped with a comprehensive range of inputs and outputs, the BP25 accommodates various audio sources, including CD players, turntables, and digital audio players. One of its notable features is the inclusion of both XLR and RCA connectors, allowing for versatile connectivity options. The BP25 also features a high-quality headphone output, making it a versatile solution for both casual listeners and serious audiophiles who demand superior performance across different listening scenarios.

On the other hand, the Bryston BP20 is a more streamlined model that inherits many of the technological advancements seen in the BP25, but in a more compact form. The BP20 retains the essential elements of Bryston’s design philosophy, offering low noise and high dynamic range. While it has fewer inputs and outputs compared to its larger sibling, the BP20 is still capable of delivering a robust listening experience that rivals many higher-end competitors.

Both preamps leverage Bryston’s legendary build quality. Constructed in Canada, every BP25 and BP20 is meticulously assembled, with an emphasis on long-term reliability and durability. The use of premium grade components, including high-quality capacitors and resistors, ensures that these preamps provide consistent performance over time.

In terms of technology, the BP25 and BP20 utilize Bryston’s proprietary DC power supply, which significantly enhances the overall audio performance. This innovative power supply minimizes unwanted noise and ripple, resulting in a pure power source for the preamps.

With their exceptional performance, diverse connectivity options, and durable construction, the Bryston BP25 and BP20 preamps represent a commitment to quality audio reproduction, making them standouts in any high-fidelity audio system. Whether you are building a new system or upgrading an existing one, both models are worthy choices that promise to elevate your listening experience to new heights.
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