Woo Audio WA 22 Headphone Amplifier (Playback 43)

Transparent, Balanced & Very Realistic

I tested the Woo with a wide variety of headphones, including the Sennheiser HD800 and HD650, the Grado PS1000 and 325is, the Ultrasone Edition 8 and the Denon AH-D5000. This is where things got interesting. In 90% of these cases, I thought the mid-range was slightly more present and vivid with the WA22 than with the other headphone amps I had on hand. The effect I’m talking about doesn’t sound like a frequency response bump, but rather like an increase in midrange contrast (the analogy here is to images, where contrast is a separate factor from color or resolution). Another way of expressing this is to say that micro- and macro-dynamics in the mid-range were slightly better with the WA22 than in other top-tier headphone amps I’ve heard thus far. This generally made each headphone sound more realistic and more like live music.

Bottom Line

This quality of more realistic mid-range contrast was one I observed with the WA22 across many, but not all, of the headphones I tried. So while my reactions to the WA22 were extremely favorable, I must in fairness say “your mileage may vary,” because you may not be using any of the headphones I tried, and because the ‘phones you choose might conceivably behave differently than the test ‘phones I used. I should also add that once you settle on a specific set of headphones, there could be other amplifiers that address specific performance issues with your headphones better than the Woo does. But if you are looking for an amp that will make most of the headphones you try shine, I can and do highly recommend Woo Audio’s WA22.

Specs & Pricing

Woo Audio WA22 Headphone Amplifier
Power output: 810 mw with 6080, 2 watts with 7236 power tubes
Frequency response: 8 Hz - 50 KHz, -3dB
Ideal headphone impedance: 8-600 Ohms
Amplifier Input impedance: 100k Ohms
Analog Inputs: One single-ended stereo pair (via RCA jack), one balanced stereo pair (via 3-pin XLR jacks), with single-ended/balanced input selector switch
Analog Outputs: three balanced headphone outputs (one stereo output via 1/4" phone jack, one stereo output via a single 4-pin XLR jack, one via a separate left/right pair of 3-pin XLR jacks), hi/lo gain selector switch
Signal/Noise ratio: 92 dB
Distortion (THD): <= 0.3%
Dimensions (H x W x D): 7” x 12” x 10.5”
Weight: 25 pounds
Price: $1900 (standard model); Power Tube upgrade (matched pair, Sylvania 7236), + $120; Driver Tube upgrade (matched pair, Shuguang CV181-Z/6SN7GT), + $280; Rectifier Tube replacement (Sophia Princess Mesh Plate 274B), + $150

Associated Equipment
Esoteric DV-60 universal player (in PCM>DSD mode), Shunyata Python power cables, Nordost Blue Heaven interconnects, Sennheiser HD 800 headphones, Sennheiser HD 650 headphones, Denon AH-D5000 headphones, Ultrasone Edition 8 headphones, Grado PS 1000 headphones, Grado SR-325is headphones, Grado SR-225i headphones, Bose QC1 headphones, Luxman P200 headphone amplifier, PS Audio GCHA headphone amplifier, Headroom Head-Direct HA-1 amplifier

Woo Audio
Fax: (718) 764-6393
wooaudio [at] gmail [dot] com ">wooaudio [at] gmail [dot] com
www.wooaudio.com