NHT Xd: Home Loudspeakers Will Never Sound the Same

July 2004 – NHT (Now Hear This) is debuting a new DEQX Calibrated DSP-corrected, powered speaker system that reduces distortion and offers impeccable frequency and phase response, regardless of placement or listening position.

NHT Xd is the result of the combined efforts of three companies – NHT, DEQX (Digital Equalization and Crossover), and PowerPhysics – that pooled their respective core technologies to develop a system that removes virtually all possible distortion from the audio signal path while providing a much wider soundfield that remains accurate, even when listening far off axis. The system features two small speaker cabinets; a powered bass, or woofer module; and a hybrid outboard component that houses the DEQX-calibrated DSP (digital signal processor) and PowerPhysics One-Cycle Sound amplifiers. Additional channels and bass modules can be added to create surround systems.

“The loudspeaker is the weakest link in any audio system,” said Chris Byrne, NHT’s co-founder and Managing Director, Rockford Home Group. “No matter how high the price or defined the engineering, a traditional passive loudspeaker is going to add substantial distortion and frequency response errors. Combine this fact with necessary compromises in passive crossovers -- as well as unknowns such as amplifier power, proximity of boundaries and speaker placement -- and it’s no wonder that end-users become frustrated with having to sit in the ‘sweet spot’ to achieve reasonable sound quality in their homes.

“NHT Xd is the first real response to consumer demands for high performance, smaller systems that offer truly flexible placement and ultimately lead to a wider soundfield that remains precise and accurate no matter where the listener is situated.”

NHT Xd: Three Key Ingredients
Just as the NHT Xd is the offspring of three companies’ design efforts, the system itself is comprised of three essential components.

Capitalizing on the proven benefits of DEQX Calibration, the NHT XdA DSP/amplifier is the “brain” of the system. Designed to be a truly plug & play solution, the NHT XdA includes only a few intuitive controls: one for each channel, allowing the end-user to set boundary equalization, i.e. an adjustment for maximizing performance when speakers are placed on or next to a wall, on a stand in the middle of the room, on a TV, etc. There are two sets of inputs – RCA and differential balanced (XLR) -- as well as outputs in the form of five-way binding posts, four for each channel, with balanced line level outputs for connecting bass modules.

The amplifier section of the NHT XdA contains four PowerPhysics One-Cycle Sound amplifiers that supply high-efficiency, bi-amplification of stereo channels, and two balanced, line-level output channels for the woofer(s). PowerPhysics’ proprietary Class D amplifier is compact and highly efficient, generating the bare minimum of heat, allowing NHT to put all electronics into a single chassis measuring 2.6”H x 17”W.

The diminutive (10.25”H x 6.5”W x 8.5”D) NHT XdS satellite speaker features a two-way, acoustic suspension design that houses an ultra-low distortion 5.25” midrange and 1” neodymium tweeter. A massive “heat sink” is attached to the rear of the tweeter to provide substantial power handling, while the cabinet baffle itself is molded from a dense, sonically neutral composite material designed for far-reaching sound dispersion. Each satellite is bi-amplified, with the midrange and tweeter each powered by an individual amplifier.

Rounding out the NHT Xd system is the NHT XdW powered bass module, comprised of two active, opposed 10-inch drivers and a PowerPhysics 500W amplifier. Unlike other powered woofers, the XdW features only three controls – volume trim, balanced input, and voltage selection. (Crossover functions such as frequency response, phase, crossover point, and time domain filtering are managed by the XdA.)

In the near future, NHT will offer a backwards compatible, wireless (digital 2.4GHz transmission) option for the bass module, in addition to the wired input. Additionally, the NHT Xd system is designed to be upgradeable, so end-users will be able to augment their systems as new DSP-based functions are introduced.

For more information, visit www.nhthifi.com.

SOURCE NHT