Formerly marketed under the Vergence brand, NHT Pro is back as the professional division of NHT. To take a twist on the milk slogan, “everybody needs lots of bass,” especially when keeping up with 5.1 monitoring systems and high-powered near-fields. With that in mind, NHT Pro offers the B-20, a well-thought-out system that interfaces with the company's own flagship A-20 monitors (reviewed June 1999) or other monitors either in stereo or for LFE in 5.1 arrays.
The B-20 package consists of two 38-pound, 14-inch cube acoustic suspension enclosures with high-excursion, 10-inch woofers behind kick-proof grilles. The beefy 37-pound rack unit provides 250W/channel, and status LEDs indicate Power, Clip, Bypass and Mono/Stereo modes. Controls adjust input sensitivity, highpass filtering on the satellite feeds (35/65/85/110 Hz and full range) and five-position bass boundary compensation. The bass phase may be switched over a wide range (180/90/0/-90/-180°) to optimize subwoofer summing with the satellites; there is a sub lowpass control to limit the highest frequency the sub will reproduce (70/85/95/105 Hz and full range). Finally, a sub gain rotary attenuator (0 to -20 dB) matches the sub level with the satellites. All necessary cabling is included.
Like the A-20 system, the heart of the B-20 is in the control amp. Unlike other powered subs, all the tweakable parameters for optimizing the sub's system response to your monitoring environment are on the rack unit's front panel, so any adjustments can easily be made at the listening position. There's no need to leave the sweet spot to make a change during setup, so beyond some experimenting to find the right placement, it's relatively easy to optimize reproduction and minimize room interaction. Once the system is set up and matched to your speakers and room, you can “set-and-forget.” The B-20 also includes a useful hardwired remote control for switching from stereo to mono or bypassing the sub during playback ideal for checking for phase problems or mono incompatibility in the tracks or getting a real-world assessment of the mix without the subs engaged.
We tested the B-20 as a mono-fed LFE in a 5.1 system with five TOA 280ME-AV near-fields and as a stereo subwoofer supplementing a pair of bi-amped Meyer HD-1s. The B-20's system performance is stated as 29 to 100 Hz with a peak acoustical output of 110 dB at 40 Hz. The TOAs are low-efficiency, sealed three-ways that almost brickwall below 100 Hz and really need a sub, whereas the Meyers are flat down below 40 Hz two very different scenarios. In both cases, the B-20 addition made a significant improvement in the sound, offering bass response that was natural, tight and seamlessly integrated with the other speakers. We also paired the B-20 with a pair of Martin Logan Aerius electrostatics owned by Mix's resident audiophile, Dan Hernandez. The result was nothing short of awesome: huge and full yet fast and responsive!
Listing at $2,000, the NHT Pro B-20 isn't cheap, but with its 2×250-watt amps, control electronics and dual high-output subs, the system offers a solid solution for enhancing existing or new monitoring systems in the pro or project room.
NHT Professional; www.nhtpro.com; 707/748-5940.