Boulder Expands Its 800 Series with the 808 Phono Stage and Compact 851 Monoblock

Boulder has introduced two new components in its 800 Series. The line-up now includes the Boulder 808 MM/MC phono stage and the Boulder 851 monaural power amplifier. Both products continue the concept of the series: to offer a serious level of High End performance in relatively compact enclosures. The new models are aimed at advanced stereo systems where sound quality and reliability matter, but so does more practical placement of equipment in an audio rack.

The Boulder 851 is a compact monaural power amplifier that largely builds on the solutions familiar from the 861 stereo model. The amplifier delivers 100 W into an 8-ohm load and 200 W into 4 ohms, while peak output can reach 350 W when impedance drops to 2 ohms. According to the manufacturer’s concept, the model is intended to retain Boulder’s characteristic control, transparency and operational stability, while offering them in the format of a separate amplifier for each channel.

One of the key features of the Boulder 851 is its Smart Current output stage – this is the first amplifier in the 800 Series to use the technology. In addition, the manufacturer specifies an ultra-wide bandwidth, low distortion and a well-developed protection system. The equipment includes a balanced XLR input and 6 mm speaker terminals. The stated total harmonic distortion is 0.002%, while the frequency range is specified from 0.015 Hz to 150 kHz at -3 dB. The enclosure measures 30.5 × 8.9 × 30.5 cm and weighs 10 kg.

The second new model is the Boulder 808 phono stage, designed to work with MM and MC cartridges. Within Boulder’s own hierarchy, it sits between the 508 and 1108 models and is aimed at owners of vinyl systems who need a more advanced analogue signal path without moving up to the larger components of the senior series. Externally, the unit follows the same design language as other products in the line-up, including the 812 DAC Preamplifier and 861 Stereo Power Amplifier.

When developing the Boulder 808, particular attention was paid to noise reduction, internal layout, shielding and mechanical rigidity of the enclosure. The phono stage is equipped with balanced XLR inputs and outputs, supports MM and MC cartridges, offers mono playback mode and a defeatable low-frequency filter. MC cartridge loading is adjusted using interchangeable Personality Cards installed on the rear panel of the unit.

The load adjustment range for MC cartridges reaches 1,000 ohms, while MM cartridges use a fixed 47 kOhm load. Gain is rated at 70 dB in MC mode and 44 dB in MM mode. The frequency response is specified as 20 Hz to 20 kHz with a deviation of ±0.25 dB, while total harmonic distortion is rated at 0.01%. Pricing for the Boulder 851 and Boulder 808 has not yet been disclosed by the manufacturer.