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This is the eleventh in a series of reviews dedicated to the concept of 32Ohm Audio as embodied by the store of that name in downtown Portland/Oregon and described here - Ed.

Reviewer: Joël Chevassus
Financial Interests: click here
Source: Audio Analogue Grand Maestro CD, Luxman D-06 [on loan], Apple iMac, Trends UD-10.1 USB 06 [on loan], Zhaolu D-3.5 06 [on loan],
Headphones outputs: Trends UD-10.1, Zhaolu D-3.5 06 [on loan], Luxman L-590 A II 06 [on loan]
Headphones: AKG K701, AKG K240 Monitor, Nuforce UF-30, Shure EC2.
Cables: Naturelle Audio XLR cables Live 8 and Live 4 interconnects, RW Mogami mini to mini cable, RW Mogami mini to stereo RCA cable, RW Silver series RCA interconnect cables, Lintek RCA-CS interconnects [on loan], Lintek digital cable PSV- 063 [on loan]
Review Component Retail: ca. $149 CAD for Amp1, $60 CAD for Amp1 upgrade


Context:
RW Audio is a Canadian company established by Robin Wainwright in 1999. RW Audio started building car stereo signal processors and many car stereo SPL world records were set using RW Audio line drivers. In a way, RW Audio has been a mythic brand for car audio addicts, and audio line drivers designed by Robin Wainwright were considered among the best.


When traditional home audio specialists were experiencing the diversification to car audio for the luxury car segment, the little Canadian company decided in 2006 to explore new horizons and enter the home and portable audio market. The first headphone amps designed by the owner of RW Audio were mainly derived from car stereo products. But in 2008, Robin set new goals for his range of home audio products on sound quality, external design, build quality, originality and affordability. If Naim had chosen to export to the 'Bentley Kingdom' prestigious refinements from the high-fidelity industry, why could a native car audio protagonist not do the opposite and try to bring price competitiveness into the home audio sphere? As we know, car audio is a very competitive market.  Most players have sufficient skills to get one foot into the home audio business. In France for example, Focal is marketing to both markets and their car audio activites can partially explain why the company today is the first player in the domestic speaker market.


Turning back to more modest scales, Robin Wainwright uses few words to describe what kind of project RW Audio truly is and is not:

"RW Audio is an outlet for a hobby and a passion.
RW Audio is hand assembled piece by piece because I love doing it.
RW Audio is proudly made in Canada because I wouldn't do it any other way."

"RW Audio isn't the next big audio company to import products.
RW Audio isn't 5-figure price tags for equipment that substitutes as status symbol.
RW Audio isn't flashy neon lights to make design compromises look better than they really are."



I was instantly seduced by this focus and agreed with Robin on a future review inside these pages. As RW Audio mainly targets the US and Canadian markets, Robin took time to find the correct 230V power supply before sending me a sample of his current production. His sells direct from the website and at very reasonable prices.


Today RW Audio produces three ranges of product: car audio line drivers, portable and desktop headphone amplifiers, cables & interconnects. This review investigates the desktop headphone Amp1, the only product thus far in the company’s second range. Quite soon we’re to expect another portable amplifier with balanced outputs. I subsequently shall also assess the global customer service of the company and the various accessories and cables that Robin sent with the Amp1.


Description: The RW Audio Amp1 is a compact device availablew with silver or black-anodized panels. The external design is very simple and functional yet elegant. This amplifier will have no difficulty finding a place on your desktop. The only external setting is via solid aluminum knob to control an Alps potentiometer in the middle of the front panel. The internal design sports socketed op-amps for easy rolling.



The external +/-12V power supply allows compatibility with many op-amps like the AD8620, OPA627 or LT1057. Inside is a hi/lo gain switch to adapt to various headphones. There are in fact 4 dip switches. The left pair bypasses the coupling capacitors for DC coupling. In the off position, the amp is  AC coupled with a slight loss in sound quality. By default the amp is DC coupled. The right pair of dip switches is for gain adjustment. 'On' equals low gain and should be sufficient for most combinations of source output and headphone impedance. Some combinations may want extra gain either due to higher impedance/lower efficiency headphones or a source with lower than average output.  By default the amp is set to low gain.


Input and outputs are minimalist 3.5mm exclusively to require a mini-to-stereo link to connect with a conventional CD player. Principally designed as a desktop device, a standard mini-to-mini link will connect to a computer sound card or iPod-type 3.5mm headphone output. Ditto the headphone output which requires a 3.5mm to ¼" adaptors for ‘audiophile’ headphones.


The rear-panel variable preamp output can connect to active desktop loudspeakers. When headphones are plugged in, this output automatically mutes and vice versa. All cables sold separately by RW Audio are Mogami quad-conductor shielded designs delivering excellent performance and neutrality for the price.


Taking into account the simple but efficient design of his headphone amplifier, Robin Wainwright considers it neither useful nor promising to think about substantial modifications. The built-in price/performance ratio has been a constant concern for the designer to feel confident that nothing was overlooked. Careful attention was placed on sound quality, reliability, appearance, stability and focused upgradeability. The Amp1 uses the National Semiconductor LME49860 dual op-amp and no costly boutique parts, most of which were found to not add appreciably to the end result. According to Robin Wainwright, they only would drive up production costs and diminish value.


The only upgrade envisioned useful relates to more expensive op-amps. For $60 Canadian, a pair of socketed LME49720HA make sense as they are basically the metal can version of the LME49860. RW Audio also offers a DIY kit to assemble the production version for half the cost of the turn-key unit. The assembly instructions may be downloaded directly from the RW Audio website and are very detailed and coherent.


For specifications, we get 20Hz – 20kHz response +0.01/-0.05dB, A-weighted noise level of -105.5dB, dynamic range of 96.5dB, THD of 0.0021%, IMD+Noise of 0.0039% and stereo cross talk of -96.8dB.


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