NuForce HA200 (Black)

The NuForce HA-200 is a high performance, Single Ended, Class-A Headphone Amplifier engineered to satisfy the requirements of the most devout headphone enthusiast.

As personal music listening and headphone use has become an ever-greater part of the audio market, the desire for uncompromised headphone amplification among devout enthusiasts has increased accordingly. The HA-200 was developed to specifically meet this need by uniting the most musically accurate technology available along with renowned NuForce value.

As an ultimate high-performance headphone amplifier, the HA-200 starts out with Class-A design and then combines that with a constant current output topology. Furthermore, when it is operated in classic Stereo Mode it also offers true Single-Ended (SE) output performance. As a valuable plus, two units can easily be combined to provide true Balanced Headphone Mode operation, which quadruples the available output power (2X voltage = 4X power) while increasing transient speed and dynamic control over the music.

Balanced Headphone Mode

Unique to the HA-200 is its ability to quadruple output power by simply adding a second unit and operating them together in "Balanced Headphone Mode." For this configuration, all that's needed is to use the XLR inputs and outputs on each HA-200 along with a special cable adaptor for connecting the headphones.

In Balanced Mode, four completely separate amps (2 per unit) are utilized to drive the four phases of the music signal (right normal, right inverted, left normal, left inverted). Please keep in mind though that this is NOT the same technique as mentioned above in the "push-pull" Class-B scenario. In Balanced Mode, all transistors are biased in Class-A so as to conduct current at all times – only the phase is inverted 180 degrees in the case of the left & right inverting amplifiers.

The primary benefit of such a design is that the available output voltage is doubled, so the actual output power is quadrupled. It also doubles the effective slew rate (the maximum change in voltage per second that an amplifier can achieve), as both amplifiers are operating in opposite phase to increase the dynamic realism of the music. While "technically" not a pure SE design, since Balanced Mode remains in full Class-A operation at all times it can be thought of as a "dual SE" architecture that retains the best of SE performance with the added benefits of higher power and better dynamic control.

Sonically, the resulting sound is completely "grain-free," the soundstage is wide and deep while instruments and voices are reproduced with extreme clarity and purity of tone. The incredible power and dynamic control over the music simply must be experienced to be appreciated.