300B Headphone and Speaker amplifier
WA5 amplifier unit
WA5 Headphone and Speaker amp.
WA5 Headphone and Speaker amp.
WA5 ampifier back panel
WA5 amp front, PSU back

I am completely blown away by the naturalness of the music, the realness of the sound. I listen to a lot of classical and jazz, especially small classical ensembles, piano, violin, cello, that type of music, and it is simply put, a fantastic sound coming from the W5. My K1000 have never sounded this smooth and enjoyable, with NO ear fatigue, no etched treble, and plenty of good clean bass. Not only do the K1000 sound great, but so do speakers on the W5! - by stax-i-nox at head-fi.org

What I can say is the 274B has a very different character from the GZ34 metal base. It is far from subtle. First there is more bass - both in terms of quantity and depth. Second, the overall sound is richer, or I should say, denser across spectrum. Some people may call it "sweet" but not syrupy. Third, the far end treble is not as detailed as the GZ34 and tends to roll off earlier. Overall, it is a very different presentation from the Metal Base GZ34. - fkclo at head-fi.org

Price: $5309

* One year factory warranty

* AMP and PSU ship in a molded foam within a double-wall box

* Power supply umbilical cord is included.

* 1 pair of 300B, 6SN7, and 274B tubes are included.

* AC Power cord and audio cables are not included.

* Shipping charge applied to CONUS only. International shipping charge will be invoiced when your order is in our system.

WA5 / WA5-LE flyer (PDF) pdf-icon

    Technical Specifications:
  • Two 300B [PDF] power tubes
  • Two 6SN7 [PDF] drive tubes
  • Two 5U4G [PDF] rectifier tubes
  • Voltage: AC 110/220V, 50/60 Hz
  • External dimension (each): 8½(H), 9"(W), 17"(D)
  • Weight: Amp Unit: 35 lbs, Power Supply Unit: 33 lbs
    Headphone Amplifier Specifications:
  • Headphones impedance : 8—600 Ohms
  • Frequency response: 10 Hz—60 kHz, -2dB
  • Power output: up to 8 watts via 4-pin XLR and 1/4"
  • Signal/Noise: >= 95 dB
  • THD: <= 0.08%, 1kHz
    Speaker Amplifier Specifications:
  • Power output: <= 10w @ 8 Ohms, THD <= 0.3%, 1kHz
  • Frequency response: 16—38 kHz, -2dB
  • Output impedance: 8 ohms
  • Signal/Noise: > 90 dB
    Standard Features:
  • Independent headphone and speaker circuits
  • Single-ended Triode, Class A, Output-transformer design
  • Point-to-Point wiring
  • User selectable High or Low Headphone POWER Output
  • User selectable High or Low IMPEDANCE
  • User selectable High or Low LEVEL headphone output
  • Audiophile-grade ultra premium internal parts: (V-Cap nput coupling Teflon caps, Jensen decoupling caps and voltage filtering caps, Black Gate bypass (6SN7 cathode) caps)
  • One XLR input
  • Two WBT Nextgen 0210-Cu RCA inputs
  • One WBT Nextgen 0710-Cu Speaker output

Power tubes upgrade 1:
Takatsuki 300B matched pair, made in Japan.
$1900 with 12-month warranty

The Takatsuki TA-300B are new production tubes and is packaged in an exquisite wooden presentation box. It’s performance and quality are verified by us to ensure our customers are getting the best of the best. These tubes rival the NOS Western Electric 300B in sonic performance.

Click to see details.

Power tubes upgrade 2:
KR 300B HR matched pair (North America version)
All tubes are tested by us in an actual amplifier to meet the highest quality.
$1295 with 6-month warranty

KR Audio is the world leader in the production of high performance audio power tubes and high-end audio equipment. All products are hand-crafted, using high vacuum machines for extended tube life. Artisans work with metal, glass blowing and tube designs optimized for high-end, high resolution audio.

Power tubes upgrade 3:
Sophia Princess 300B Mesh Plate black base matched pair.
$385
Comparable to Western Electric 300B. Buy and ship independently.

The result is a 300B mesh plate tube with super clarity, low distortion and out of this world mid range fullness and liquidity. High frequency extension and sweetness is the first thing you would hear. This is a true 300B tube that is 100% interchangeable with the popular Sophia Electric globe shaped 300B mesh plate tubes and Western Electric 300B tubes, as well as current production Chinese/Russian 300B tubes (with WE 300B standard).

Driver tubes upgrade:
Hand-pick matched pair
RCA/GE/Sylvania 6SN7GT NOS tubes
We tested these tubes in an actual amplifier to ensure the highest quality.
$330 (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 tubes upgrade 1:
Takatsuki TA-274B matched pair
$2090 (2 pcs) with 1-year warranty

Takatsuki 274B offer ultimate performance to any current production 274B's. Users have claimed that it exceeds the quality to NOS Western Electric 274B.

The TA-274B sold in an individual package Click to see details.

Rectifier tubes upgrade 2:
KR 274B High-Resolution, single
$1295 (2 pc) with 6-month warranty

The KR Audio 274B HP rectifier tube is a perfect compliment to any tube amplifier’s high voltage power supply. Solidly made and very low in microphonics make this a no brainer to properly power the finest tube amplification. This latest high performance design better controls both electrical and vibrational resonances that blur imaging for greater clarity to the source.

Image of a KR 274B HR rectifier

Rectifier tubes upgrade 3:
Sophia Princess Mesh Plate 274B rectifier.
$320 (2 pcs) with 30-day warranty

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.