I bought this RNHP headphone amp brand new, and I have barely broken it in.
It was designed by the legendary RUPERT NEVE, and it is in perfect physical and working condition.
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RNHP

Precision Headphone Amplifier

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Whether you’re tracking, mixing, or just listening to music, your headphone amplifier is as important to the final sound quality as your headphones – yet the world is full of headphone amps with compromised sonics, headroom, and power. To address these shortcomings, Rupert and his team at Rupert Neve Designs have developed the RNHP.

Based on the headphone output circuit in the 5060 Centerpiece Desktop Mixer, the RNHP is a dedicated 24V reference-quality headphone amplifier with specifically-calibrated +4dBu balanced line, unbalanced RCA and 3.5mm (1/8”) inputs, housed in a rugged VESA-mountable steel chassis. With effortless, wide-open sonic performance and the ability to drive any pair of headphones without compromise, the RNHP allows you to perform, mix and enjoy your music with a new level of clarity.

Dedicated vs Integrated Amplifiers

For much equipment, the headphone output is an afterthought. Most products with integrated headphone amps have large feature sets, small footprints, and relatively low price points. This leads to comprised power and audio quality of the headphone amplifier itself, which can lead to a number of issues in real world usage such as low headroom, unreliable performance, and a lack of focus.

The RNHP was made to accomplish one simple purpose: making any headphones sound their best. As a dedicated design, the RNHP is tailored to deliver extremely high quality, powerful amplification, with precise calibration for any source input. This exceptional level of quality can be the difference that inspires an artist to give their best performance, lets an engineer make better choices in mic and placement, gives a mix engineer reliable translation of EQ and dynamics adjustments, or lets a music listener appreciate the full depth and detail of a recording.

Specially-Calibrated Inputs For All of Your Devices

In addition to being able to drive a wide variety of headphones without sacrificing performance, the RNHP is also capable of receiving a wide array of signals with its 3 inputs, calibrated for optimum level and impedance. Check the Application notes for how the RNHP can be utilized for different purposes.

Here are some common device examples: 

Input A: +4dBu Line (XLR or TRS) Devices
Studio Audio Interfaces (Line or Monitor Out)
Headphone Mixers (Line Output or HP Out) 
Mixing Consoles (Line, Aux or Monitor Out)
Professional Turntable Mixers (Line or Monitor) 
Professional Stereo Digital to Analogue Converter
Professional CamerasStudio Monitor Controllers

Input B: RCA Devices 
CD / DVD Players
Stereo Tuners
Preamplified Turntables
Prosumer Recording Devices / Cameras 

Input C: 3.5mm (1/8") Stereo Devices 
Mobile Phones
Portable Music Players
Computers
DSLR Cameras
Handheld Recording Devices
Any 3.5mm headphone output

VESA-Mountable Design

The RNHP is designed for mounting with any VESA 100 compatible mount. These may include pole mounts, wall mounts, table mounts, or articulating arm mounts. These mounts can help to ensure the RNHP is always in the perfect position.

Multiple-Line Feed

In some situations where you only have one set of outputs but need to simultaneously feed the RNHP and another device such as speakers, a second headphone amplifier, or a 2-track recorder, we recommend using splitter cables from the Left and Right line outputs to feed both devices from the same stereo pair. 

HEADPHONES

This pro sound/audiophile headphone amp was touched by genius

Designed by a legendary engineer, the Neve RNHP headphone amplifier wows the Audiophiliac.

BY 
• STEVE GUTTENBERG

OCTOBER 29, 2016 9:53 AM PDT

As recording studio engineer/designers go, Rupert Neve is a rock star. His mixing consoles are so highly sought after, Dave Grohl made a music documentary, "Sound City," that featured a Neve console. Rupert Neve was named man of the century by Studio Sound Magazine readers in 1999, and in 1997 he won a Technical Grammy award. Neve consoles are used by such noteworthy artists as Jack White, Kanye West, Adele, AC/DC, the Rolling Stones, Willie Nelson and many others. So when I heard that Rupert Neve Designs was now making the RNHP headphone amp that might be of interest to audiophiles, I requested a review sample. The cool factor of owning a Neve design just might be impossible to resist!

Based on the headphone amplifier circuit in the all-analog, 24-input Neve 5060 Centerpiece Desktop Mixer, the Rupert Neve Designs RNHP ($499, £429, AU$849) is a reference-quality headphone amplifier with XLR, RCA and 3.5mm analog inputs (there are no digital inputs). The RNHP is made in the US.

It looks like a no-frills pro, not consumer design, but the folded steel chassis is small enough for desktop use; it's just 6.5 x 4.6 x 1.9 inches (165 x 117 x 48mm). A bright green LED glows above the selected input on the front panel, and a 6.3mm headphone jack is the only output. The RNHP is powered by a wall wart, which is included with the unit.

Soundwise, the RNHP did not disappoint when I started listening with a Beyerdynamic DT 1990 Pro headphone. Transparency was absolutely first-rate, dynamic punch was right up there and stereo imaging from this closed-back headphone was admirably spacious. The RNHP was designed to be neutral, and indeed that's what it sounds like.

Moving over to the Sony MDR 7520 headphones and switching between the RNHP and an Arcam irDAC II digital converter/headphone amp, the RNHP had a more laid-back, less forward sound. The irDAC II seemed to make harsh recordings a wee bit harsher, the RNHP was easier on the ears. The soundstage was wider, and the bass kicked harder over the RNHP.

Enlarge Image

The Rupert Neve RNHP's rear panel.

Rupert Neve Design

Even my hard-to-drive, high-impedance 600-ohm Beyerdynamic T-1 headphones didn't make the RNHP stumble. The sound is sweet and clear, but I have to admit I just loved the idea of having a Rupert Neve design sitting on my desktop!