WA3 Headphone Amplifier and Pre Amplifier. Singled-ended Triode Class-A, All Tube Drive, OTL.

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The 2 small tubes on the front are the 6922/6DJ8 driver tubes, and the big one on the back is a 6080/6AS7 power tube

The front panel (left to right) consists of a 1/4" (6.3mm) headphone jack, a volume control, and a power switch button.

Top view. Under the aluminum housing, it sits a high performance power supply

For the enjoyment of music, the WA3 sits high in its class and is well constructed to boot.

Out of the box this is a rewarding and enjoyable auditory experience. The price belies the value you are receiving. This amp is dimensional, tonally very musical, i.e.: as in real music.

Probably one of the best audio buys I've ever made and I've always been a solid state guy. This amp just makes magic with HD-650's.

The image is fairly dimensional, with a wide, deep and high soundstage, which allows you to sense the relative positions of the instruments and performers. The amp positions the listener fairly close to the performance with a more intimate sound – closer to the front row, or stage, than to the back rows.

The most notable difference seemed to be the soundstage, it is HUGE. I can easily tell from what direction all the voices and instruments are coming from now. The vocals (and entire midrange) have superb seperation, and seem to carry more weight or "authority".

Purchase this option to add one RCA line output. The pre-amp out uses the 6922 as a driver pushing the 6080 power output tube.

* 1 pair of drive tubes, and 1 power tubeare included.

* AC Power cord and RCA interconnect cables 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)

Headphones impedance : 30-600 Ohms
Input impedance: 100 Kilo-Ohms
Frequency response: 8 Hz - 100 KHz -3dB
Signal/Noise: 95 dB
THD: <= 0.08%
Pre-amp Gain: 10 dB
Voltage: AC 110/220V, 50/60 Hz
External dimension: 6"(H), 5½"(W), 13"(D)
Weight: 10 lbs

Point-to-Point wiring
One 6AS7 / 6080 [PDF] power tube
Two 6922 / 6DJ8 [PDF] drive tubes
One RCA input
One pre-amplifier output
1/4" (6.3mm) stereo headphone jack
Full aluminum die-cast chassis, anodized finish
Whole aluminum volume knob and power switch button
80 watts specially made toroidal transformer
Gold-pin tube sockets
Gold-plate RCA
Alps potentiometer and power switch
Silver-plated hook-up wires in Telfon jacket

Power tubes upgrade:
Tung Sol 7236 NOS $80 each

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 2:
Hand-pick matched pair
Amperax 7308 $290 (2 pcs)

Ultra low noise and low microphonic, deep, clean bass, excellent extension on tremble, full body mid range. Buy and ship separately.