![]( "WA22 - fully balanced headphones amplifier")
It is transparent, particularly in that you don’t notice any treble veiling or grit as you do with some lesser headphone amps. Bass is solid, well defined and can be very deep with the right headphones. Tonal balance is very, very good, with no sense of treble roll-off or brightness.![Link to original posting]()
Woo 22 balanced headphone amp which, with the premium tube upgrades, presents the most effortless, immediate presentation of sound I have heard from any headphone system, or perhaps any stereo system.![Link to original posting]()
The Sennheiser HD800 headphones and the Woo Audio WA22 integrated headphone amp configured in fully balanced configuration is _disibledevent="Apple-converted-space"> ![Link to original posting]()
I have since tried HD 800’s with the prototype Woo Audio WA 22 amp (which is tube rather than solid state apm that has variable output mpedance). The WA 22 takes the sense of vividness up a notch, mostly by making the midrange contrast level higher, while introducing minimal if any deleterioius side effects. The mostly subtractive errors noted above are still there, but they are diminished in the overall presentation. This gets me to the level of really, really liking the HD 800s. The HD 800s are so good that I could easily live with them over the long haul. (page 115)![Link to original posting]()
* Included tubes: 1 pair of 6AS7, 1 pair of 6SN7, and 1 5AR4
* Tubes shown _disibledevent="Apple-converted-space"> not included.
* AC power supply cord, interconnection cable are not included
* Shopping cart applies to the U.S. buyers only. International buyers please contact for shipping cost and payment instruction.
Owner's Manual(PDF) ![pdf-icon]()
Technical Specifications:- Headphones impedance : 8-600 Ohms
- Input impedance: 100 Kilo-Ohms
- Frequency response: 8 Hz - 50 KHz, -3dB
- Output: 1500mw @32 ohms, 700mw @600 ohms
- Signal/Noise: 92 dB
- THD: <= 0.3%
- External dimension: 7”(H), 12”(W), 10.5”(D)
- Weight: 25 pounds or 11.4 kg
- Voltage: AC 110/220V, 50/60 Hz
Standard Features:- Point-to-Point wiring
- True balanced topology
- All tubes. No semi-conductors in the entire circuitry
- One 5AR4 [PDF] rectifier tube. Direct substitute: 5U4G
- Two 6SN7 [PDF] drive tubes
- Two 6AS7 / 6080 [PDF] power tubes
- DACT CT2 balanced stereo stepped attenuator
- One balanced XLR input
- One single-ended RCA input
- Two 3-pin balanced headphone output (left and right ch)
- One 4-pin balanced headphone output
- One single-ended headphone output
- High and low impedance switch
Power tubes upgrade:
Sylvania 7236 NOS 1963
Hand-pick matched pair $120 (2 pcs)
One of the best power tubes available for this amp. The 7236 vastly improves dynamic and soundstage. It has a very good speed, warm mid range, tight and deep bass. Buy and ship separately.
Driver tubes upgrade:
Hand-pick matched pair
RCA VT231 Smoke Glass NOS tubes
We tested these tubes in an actual amplifier to ensure the highest quality. $280 (2 pcs) with 30-day warranty.
You get a clean and dense sound image with these tubes. It is very low noise, smooth and delicate in the upper frequency range, deep and solid bass, high clarity.
Rectifier tube replacement:
Sophia Princess Mesh Plate 274B rectifier $150 (1 pc) with 30-day warranty
Wide open soundstage, full body, silky smooth, a great combination with the above tubes. Buy and ship independently.
Sophia Electric™ 274B tube is a premium rectifier tube for a 5U4/5R4/5AR4 direct replacement with 3X longer plate structure, thus it has a deeper, wider sound stage and even smoothier sound than Mullard 5AR4.
