Woo Audio WA6 Headphone Amplifier - Generation 2 - Silver

An All-Tube Amp at an Honest Price

Many headphone amps use a tube for flavor and transistors for the work. The Woo Audio WA6 does not. It is a single-ended triode, Class-A, all-tube design. There are no transistors or chips anywhere in the audio path. The output is transformer-coupled, so your headphones never see the tubes' high voltage.

Two 13DE7 tubes act as driver and power stage. A 5U4G rectifier handles the supply. The circuit is self-biasing, so tubes can be swapped without adjustments or meters. That is why tube rolling is such a large part of the WA6's appeal.

A high/low impedance switch matches the output to headphones from 8 to 600 ohms. Sensitive in-ears and 600-ohm studio models both work. One pair of RCA inputs and one 1/4-inch jack keep the layout simple.

Hand-Built in New York

Every WA6 is wired point to point by hand. Inside are an ALPS volume control, Dale and Vishay resistors and silver-plated Teflon wire. A custom 80-watt toroidal transformer feeds a pseudo-dual power supply. The chassis is anodized aluminum, in black or silver.

The second generation arrived in April 2017. It moved the driver tubes from the 6-volt 6DE7 to the 13-volt 13DE7, a change that widens the choice of compatible tubes. The rest of the design Woo has been refining since 2006 stays as it was.

It measures 6 inches tall, 5.5 wide and 13 deep, and weighs about 13 pounds. It runs on 100 to 220 volts without a converter. The AC cord and interconnects are not included.

What Reviewers Are Saying

Mark Fleischmann reviewed the WA6 for Sound & Vision on October 24, 2014. With the right headphones, he found it "delivers a creamy, grit-free tone" that solid-state amps rarely match. He noted it suits bright headphones especially well.

Mike of Headfonia called the WA6 "one of my favorite amplifiers" in a November 19, 2009 review. He was struck that it worked with two headphones of opposite character, the Sennheiser HD650 and the Grado HF2.

Who Is This Amplifier Best For?

• You want real tube sound, not a tube as decoration — the WA6 is all-tube from input to output, with no transistors in the signal path
• You own bright or forward headphones — reviewers found its smooth character takes the edge off emphatic treble
• You want to roll tubes — self-biasing and PTFE sockets make swapping the 13DE7s and the rectifier simple
• You want a hand-built amp from a specialist — point-to-point wiring, assembled in New York, backed by a three-year warranty
• You want balanced outputs or a preamp — the WA6 is single-ended with no line output, so look at the balanced designs in our headphone amplifiers

How Does It Connect to Your System?

Connect a DAC, CD player or any line-level source to the RCA inputs. Plug headphones into the 1/4-inch jack on the front and set the impedance switch to match them: low for most dynamic headphones and in-ears, high for 300-ohm and 600-ohm models.

Give the tubes a few minutes to warm up before serious listening. Leave space above the amp, because a Class-A tube design runs warm.

Pairs Well With

Building your system? Here are some great companions for the Woo WA6:

• Headphones: Dynamic headphones from 8 to 600 ohms are its natural partners — see our Headphones
• DAC: A good source is where the WA6 earns its keep — see our Digital-to-Analog Converters
• Interconnects: RCA from source to amp — see our Interconnect Cables
• Power Cable: The AC cord is not included — see our Power Cables

Frequently Asked Questions

What changed in the second generation?

Woo moved the driver/power tubes from the 6DE7 to the 13DE7 in April 2017. The circuit, chassis and transformer-coupled output are otherwise the same.

What tubes does it use?

Two 13DE7 driver/power tubes and one 5U4G rectifier. The circuit self-biases with compatible tubes, so rolling needs no adjustment.

Which headphones does it drive?

Dynamic headphones and in-ears from 8 to 600 ohms. A front-panel switch selects high or low output impedance to match.

Does it have a DAC or balanced outputs?

It is an analog, single-ended headphone amplifier with one RCA input and one 1/4-inch output.

How is it different from the WA6-SE?

The WA6-SE moves the power supply into a separate chassis and uses different tubes. The WA6 keeps everything in one box.

What's the warranty?

Woo Audio covers the WA6 with a three-year limited warranty. The stock tubes are covered for 30 days.

Why Audio Advisor?

• 40+ Years of Expertise — Since 1981, we've helped over a million music lovers find the right gear.
• 60-Day Money-Back Guarantee — Take your time. Listen, enjoy, and make sure it's right for you.
• Real Experts, Real Help — Our team is here to answer your questions at 800-942-0220, weekdays 9am–6pm EST.
• Free Shipping — On orders over $49, delivered to your door.
• Flexible Payment Options — Financing available so you can start listening now.

Learn More

Want to learn more about tube versus solid-state headphone amps, matching an amp to your headphones, or building a headphone system? Visit our Learning Center for guides, tips, and expert advice.