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Company Background
In 2005, NuForce invented an amplifier that utilizes self-oscillating switching principles in an
analog-based topology (US patent #7,221,216) as a significant departure from bulky Class
A/AB designs using tubes or transistors, and Class-D digital designs that convert signals into
digital data. Thanks in full measure to unique innovations, the NuForce Reference 9 amp
received the Power Amp of The Year 2005 award from The Absolute Sound, a prestigious
American audiophile magazine. Subsequent versions of the Reference 9 received similar
awards in Japan and France. In the years that follow, NuForce has grown to include a full line
of Mobility, Home Theater and Home Stereo products.
In 2014, having decided to focus on mobility products, NuForce sold the high-end line along
with its technology to investors who then created NuPrime Audio. Under the leadership of
NuForce co-founder and original CEO, NuPrime has assembled a design team comprised of
talented engineers who earlier worked on NuForce’s high-end line along with newly recruited
experts in switching-power circuit design. Recent developments have made it possible to
redesign NuPrime’s switching- amp topology from the ground up in order to create a new
generation of amps classified as Reference LE. The NuPrime DAC-10H is developed as a
Reference class Digital to Analog Converter for both the Reference and Reference LE class
amplifiers.
From Hi-Res to Extreme Resolution
High-volume storage has become cheap enough for the proliferation of hi-res music beyond
CD quality (16-bit/44.1kHz). Storing 24-bit/96 kHz or 192 kHz music with PCM encoding in
uncompressed format (typically WAV) or lossless compression format (such as FLAC, M4A,
WMA) has become standard practice for audio enthusiasts.
Music is typically recorded in 24 or 32-bit PCM or DSD format at the recording studio. It is then
converted to lower resolution format for mass-market distribution.
Pulse-code modulation (PCM) is a method used to digitally represent sampled analog signals.
It is the standard form of digital audio in computers, compact discs, digital telephony and other
digital audio applications. In a PCM stream, the amplitude of the analog signal is sampled
regularly at uniform intervals and each sample is quantized to the nearest value within a range
of digital steps. A PCM stream has two basic properties that determine the stream's fidelity to
the original analog signal: the sampling rate, which is the number of times per second that
samples are taken, and the bit depth, which determines the number of possible digital values
that can be used to represent each sample. DXD is simply PCM 24-bit/352.8 kHz.
Direct-Stream Digital (DSD) is the trademark name used by Sony and Philips for their system
of digitally recreating audible signals for the Super Audio CD (SACD). DSD uses pulse-density
modulation encoding – a technology to store audio signals on digital storage media that are
used for the SACD. The signal is stored as delta-sigma modulated digital audio, a sequence of
