Since 2008 Woo Audio has been offering the WA5 and WA5-LE tube amplifiers as endgame solutions to those seeking that last 2% upgrade in their system.Many feel the 300B is the ultimate audio tube due to its open and seductive sound. I discovered that 300B magic for myself two years ago when I decided to purchase a WA5 headphone and speaker amplifier for my own system. At the time, I owned four pairs of headphones, the Sennheiser HD 800, Fostex TH-900, Audeze LCD-3 and HiFiman HE-6. The WA5 drove all the headphones beautifully, and it immediately became my reference tube headphone amplifier. Nothing I had heard previously rivaled its sweetness and effortless liquidity. I had previously owned the WA2, WA6-SE, and WA22, three amplifiers which sit below the WA5 in the Woo lineup. The WA5 was a huge upgrade and on a completely different level and is a world class amplifier! A few months after the arrival of the WA5 I added a pair of Omega desktop speakers to my system and the WA5 with its 8 watts of 300B tube-driven power brought them to life. I had found my endgame solution and decided to never sell my WA5. To this date, I still have it.
At the time, the WA5 retailed for $3500 and the WA5-LE for $2750. The WA5 provided roughly 1.5 watts of power out of its single-ended headphone output and 8 watts through both its speaker outputs and its “K1K” output, which is a 4-pin XLR output which was used to drive the most power hungry headphone mainly the AKG K1000. The “K1K” output also proved to be one of the best solutions for driving the notorious HiFiman HE-6, which you pretty much need a speaker amplifier to get the most out of them due to their low sensitivity. The WA5-LE “lite edition” is the same amplifier as the WA5, minus the dedicated speaker circuitry and 4-pin XLR output and designed only for headphones.
Back in August, Woo Audio refreshed and updated the WA5 and WA5-LE, the first major revision since they were released. The WA5 is now $5899 and the WA5-LE is now $3699, a significant price increase from the old versions. The WA5 and WA5-LE now have redesigned internals with technology borrowed from their flagship WA234 monoblock amplifier and increased versatility through the addition of gain and level switches as well as 8 watt 4-pin XLR inputs and outputs. Additionally, both amplifiers are now able to output the full 8 watts of power through the single-ended headphone output. An optional $1200 parts upgrade which added premium “audiophile-grade” capacitors to the amplifier now comes stock on the WA5, and is still available as an upgrade for the WA5-LE.
In all, the new WA5 is now the ultimate version of the amplifier and is intended to be maxed out from the start, and the new WA5-LE is now pretty much identical to the WA5, minus the speaker outputs and optional upgraded parts. The new WA5-LE is my focus for this review and like any current WA5 or WA5-LE owner, I was dying to see and hear the new changes for myself.
The WA5 and WA5-LE’s timeless minimalist aesthetic still tops my personal list of most beautiful tube amplifiers. Like other Woo amplifiers, they’re just so imposing and sexy in person! The original machined aluminum chassis design remains and is pretty much unchanged from the original design. Everything from the heavy duty metal feet to the plates and screws are identical. Even the tube pin layouts are the same, which is good for those with unique tube configurations. The new WA5-LE however, does have a brighter and cleaner looking finish than my old WA5. Even after cleaning off a year’s worth of dust from my own amplifier, it simply didn’t have the same shine or sparkle present in the brushed aluminum finish of the new one.
The new WA5-LE shares a faceplate with the new WA5 and looks nothing like previous one, which was quite spartan in comparison. The WA5-LE has both a 4-pin XLR output and 1/4″ headphone output jack in the front, both capable of outputting 8 watts of power. A switch in the front allows the listener to switch between HI and LO power as well as the speaker output, although this last option is not available on the WA5-LE, it is just there to tease you about not buying the full-fledged WA5. The HI and LO power switch allows you to toggle between a maximum of 8 watts and 1.5 watts of available power, depending on the amount you need for your headphones. An impedance switch allows you to toggle between HIGH and LOW impedance, depending on whether the headphones you are listening to are over or below 100 ohms. Additionally, the new WA5-LE has a level switch to toggle between HIGH and LOW level headphone outputs, and changes the input signal level. Depending on your headphones sensitivity the gain on the output can be changed with this switch to improve noise performance. Finally, an input switch in the front allows you to switch between the 3 inputs in the back, two single-ended RCA, and a single-ended XLR input; this is still not a balanced amplifier but the extra input is nice to have.
The volume and power knobs on the WA5-LE are the same found on almost every other Woo amplifier. They are heavy, all-metal, and just as bulletproof as the rest of the amp. Like with other Woo’s, the smooth turning volume knob is excellent for fine-tuning your listening level and works well even on the new more powerful units.
Tube options remain the same and the WA5-LE has uses two 300B power tubes, two 6SN7 drive tubes, and two 5U4G rectifier tubes. Like other Woo amplifiers, the WA5-LE loves to be tube rolled and there are many combinations of compatible tubes to choose from. The Woo website has a chart to show which tubes are compatible; there are tons of tube substitutes available and one could easily drop thousands of dollars trying out different tube combinations.
The original WA5-LE in my opinion, was somewhat plain and lacking in features when compared to the WA5. The 8W 4-pin XLR is one of the most handy outputs to have, as it is able to effortlessly drive the AKG K1000, and is one of the better choices for driving the HE-6 or Abyss headphones, which requires tons of power. Even the single-ended output has the same power and this makes it much more versatile than ever as it is one of the more powerful tube headphone amplifiers out there right now and has the ability to change impedance, power, and output levels makes it easier to pair with many different types of headphones as well.
For this review my primary headphone was the Sennheiser HD 80. I am very familiar with its sound signature and it remains my reference headphone when comparing the sound of different tubes. I also used the HiFiman HE-6 as the WA5 and WA5-LE are excellent amplifiers with enough power to drive these planar magnetic headphones effortlessly. My review unit WA5-LE came stock with Psvane 300B power tubes, RCA 6SN7 drivers, and Psvane 5U4G rectifiers. Although these tubes were perfectly fine for listening and much better than previous stock tube offerings from Woo Audio, rolling in better tubes increases the layering and resolving capability of the amplifier. As such, my final reference tubes of choice were the USAF 596 rectifiers, NOS Tung Sol 6F8G drivers, and EML 300B mesh plates. I used Audioquest King Cobra interconnects as well as Audioquest Power and USB Cables. My source was lossless music files from a computer fed to the Mytek Stereo192 DSD DAC. Music choices varied and included various genres.
The new WA5-LE has a sound signature that is quite similar to that of the original. It was linear, extended, and open. The amplifier is transparent and has tons of spatial details with an ethereal presence and air around every note. The tonality is very natural and imaging is excellent. There is however, one key difference with the new model being more dynamic. The new WA5-LE is dynamic and focused across the entire frequency range there is significantly more energy behind every note. The WA5-LE is no longer a lush and polite 300B tube amplifier but one that is bolder and more involving with the flow of the music.
When listening with the Sennheiser HD 800, I experienced smooth, extended treble and a lively midrange, with spatial cues and details just popping up everywhere. Every beat feels confident and powerful, always on pace with the music and makes the new amplifier much more musical and an excellent pairing for the HD 800. When listening to ZHU’s EP, The Night day, I was able to hear the various drums, bells, and beats in “Stay Closer” with clarity as instruments came layered in the airy and open soundstage. The soundstage however was noticeably less rounded and dreamy than before. On more bass heavy tracks like “Faded” and “The One”, the bass was tight and punchy, with a slightly faster and shorter decay on the new WA5-LE compared to the old WA5. Although bass quantity is roughly the same on both amplifiers, the bass still feels more integrated with the music and you are constantly more aware of the beat.
With high resolution recordings such as the Beck’s Sea Change on DSD, I was able to fully appreciate the synergy of the WA5-LE and HD 800, as Beck’s passionate vocals on “The Golden Age” and “Lost Cause” resonated naturally and clearly over the acoustic guitar. The imaging was vivid and deep and the sounds were quite palpable, which added to the realism. Listening to Death Cab for Cutie’s Trasatlanticism on DSD was an equally rewarding experience as the 300B sound made Gibbard’s soft, soothing vocals on “Title and Registration” and “A Lack of Color” come to life and it never missed a a beat while listening to “The Sound of Settling”.
The increased dynamics and attack at the start of every note are heard easily using the HD 800 when listening to rock, metal, and mainstream music. I was able to enjoy Crossfade’s self-titled album “Crossfade” more so when using the new amplifier. Drum beats and bass notes decayed fast and cleaner with the warm 300B texture adding body and character to the sound. However, this also made compression and loudness in poorer recordings more noticeable. Flaws in less than perfect albums such as System of a Down’s Toxicity or My Chemical Romance’s The Black Parade were more apparent and the treble was hotter due to the more noticeable extension. I had to turn the volume down slightly as this amplifier was slightly less forgiving, especially with the HD 800. Rolling in warmer tubes such as my CV593 rectifiers and Sylvania 6F8G drivers was able to resolve this for the most part.
Like the original WA5, the new WA5-LE is one of the best choices for driving the HiFiman HE-6 as it is able to give it 8 watts of power and the warm smooth 300B sound is able to tame the bright treble of the HE-6. The pairing is still sweet and the sound is crisp and engaging. The HE-6 out of the K1K output on the old WA5 had a slightly fuller sound and more laid-back dynamics compared to the new amplifier. The warmth and lushness of the 300B tubes added body to the HE-6’s midrange and bass. The new amplifier offers a similar sound with the HE-6, but it is overall more linear and extended with a tighter bass decay and slightly better separation. Both 4-pin XLR and single-ended outputs are able to effortless drive the HE-6 and the sound is pretty much identical out of both outputs.
Passion Pit’s Manners showcases the pairing as the whole album just sounds fantastic with “Little Secrets”, “Sleepyhead”, and “Dreams” being absolute must-listens. The HE-6 and WA5-LE sound better than ever. Like before, the HE-6 combination works great with all genres of music but I found it especially good for rock, EDM and anything with vocals. Disco Ensemble’s First Aid Kit, Tiny Cousin’s Mastermind, Pendulum’s In Silico, and Kyla La Grange’s Cut Your Teeth were all equally enjoyable and sounded great out of the new Woo.
Like its predecessor, the new WA5-LE is unfortunately is not ideal for driving sensitive in-ear monitors. It is a powerful full-sized headphone amplifier and even with the LOW set on the new power and line level selectors it was unable to fully eliminate background noise when listening with my Noble Audio 6C customs. This noise is less noticeable when music is playing and is never present with headphones since the new WA5-LE has the same low background noise floor as before. In-ear monitors in general, will fare better with a portable amp designed for high-sensitivity low-impedance IEMs.
Overall, the WA5-LE sounds fantastic and although it isn’t necessarily more resolving or transparent compared to the outgoing model, the extra confidence and energy of the new amplifier is quite noticeable in the sound signature and it is more similar to the Woo Audio “house sound” present in other models such as the WA6-SE and WA22.
The revised WA5-LE is what the old WA5-LE should have been from the start. It has been significantly improved from the old in terms of versatility and added functions is capable of driving almost any headphone now. The sound signature offered increased dynamics while maintaining the same liquid velvety 300B presentation as before. The WA5-LE continues to provide top-level endgame sound at a reasonably and affordable price and is now the better buy if you do not plan on listening to speakers. Those who want it all, the WA5 is better than ever and now comes fully loaded stock. The WA5 and WA5-LE dynamic duo lives on!