Boulder 812 Network Streamer / Preamplifier / Headphone Amplifier

The Boulder 812 integrates network streaming, preamplification, and headphone amplification into a single, meticulously engineered component. Supporting multiple headphone formats—mini, quarter-inch, balanced XLR, and Pentaconn—alongside comprehensive streaming protocols including Roon, UPnP, AirPlay, and Bluetooth, it serves as a versatile hub for modern audio systems. Dual balanced analog inputs and outputs accommodate both headphone and preamp configurations, while optical, coaxial, and USB inputs ensure connectivity flexibility. A dedicated Boulder app enables precise calibration, including headphone sensitivity adjustments, with optional RF remote control available. Every circuit board and chassis component is manufactured in-house, reflecting Boulder's commitment to quality control and delivering exceptional value through production efficiency. The included headphone bay cover protects connectors from dust, while the output exchange button facilitates seamless switching between headphone and preamplifier modes.

Specifications

Connections (Front)- •4-Pin XLR Headphone Connector
•1/8” Headphone Connector
•1/4” Headphone Connector
•Pentacon Headphone Connector

Connections (Back)- •2 Pair XLR Analog Inputs
•1 Pair XLR Preamplifier Output
•4x USB Host
•Ethernet
•USB-B
•2 Optical Digital Inputs
•Coaxial (RCA, SPDIF) Digital Input

Software Features- •Based on 866 DSP Filter and DAC topology
•Configurable Headphone Sensitivity
•Available Fixed DAC out
•HTML Programming
•Control through the Boulder Controller App
•Input Trim

Hardware Features- •Switch Between Headphone and Preamp Outputs
•Volume Knob & Chassis Machined In House
•100 db Optically Encoded Volume Control
•Innovative Protection Circuits

Maximum Input Level- 6.0 Vrms

Maximum Output Level- 14.0 Vrms

THD+N, 2V Output, 2KHz- .0017% (-95.5 dB)

Maximum Voltage Gain- 19.4 dB

Volume Range- 100 dB

Volume Steps- 1.0 dB

Frequency Response 20 Hz to 5Khz- +0.00, -0.03 dB

Frequency Response, -3 dB- .02 Hz & 250 kHz

Clip to Noise Ratio- 116dB

Input Impedance- 100kΩ Balanced

Output Impedance- 100Ω Balanced

Power Requirements- 90-240V

Power Consumption- 50W Max

Headphone Amp Section 32Ω 200MW Output- 2k Hz 200k Hz

0.0010%. 0.0053%

Headphone Amp Section 150Ω 200MW Output- 2k Hz 20k Hz

0.0010% 0.0034%

Headphone Amp Section 600Ω 80MW Output- 2k Hz 20k Hz

0.0011% 0.0043%

Dimensions- 12”x12”x 3.5”

Weight- 14 lbs