I couldn’t find any thread (or any posts really) on SBAF dedicated to the well known and respected Woo Audio WA6-SE so I thought I would start one and share my impressions after a little more than a week of careful listening. Why a WA6-SE? I wanted a well made, all tube SET Class A amp that was reasonably powerful, didn’t require unobtainably expensive tubes, handled a wide range of headphone impedances, and sounded musical and euphonic without breaking the bank. The Woo WA6-SE caught my attention fairly early in the hunt. The reviews were consistently good if limited in number, the minimum output impedance was a manageable15 ohms, the power output was a very respectable 2W at 32 ohms, and for a beautifully hand built, point to point wired, all tube amp, reasonably priced. I probably could have saved a fair bit of money with a less fancy case, but the solid, overbuilt nature of Woo equipment speaks to me. I don’t like to pay huge amounts of money for tubes, and the WA6-SE driver/power tubes are inexpensive compared to some more popular tube types.I nterestingly, the tubes Woo used have both a driver circuit and a power circuit in the same tube. What am I Comparing it to? I’ve had a Lyr 3 for I think a couple years now and I know it pretty well. It’s an excellent amp capable of powering almost any headphone with confidence. It’s strong points include really solid bass and exceptional clarity. My current tube, a Psvane CV-181 TII, gives the amp excellent imaging and soundstage. It has no bloom at all and is very neutral. The bass is clean and distortion free into the sub bass. The treble has just enough smoothing to take out the sometimes metallic sound of my Focal Clear. Overall it’s not very tubey sounding, but not strictly solid state either. A good blend of both. What have I tweaked? The WA6-SE came with the base factory tubes. I have Sylvania NOS coming to replace the stock driver/power tubes (so nice to pay less than $25 for quality NOS matched tubes) but for this listen I used the factory driver / power tubes. I swapped out the stock cheapie rectifier with a Sophia 274B “mesh plate” because it looks cool. I didn’t give the stock rectifier much of an audition so I can’t tell you personally if the Sophia is an improvement, but there is a very good thread on Head-fi that considers the stock rectifier complete trash. Is it well made? The Woo is, by far, the most nicely made amp I’ve owned. It is overbuilt in every possible way. The case is made from thick anodized aluminum. The power supply and amplifier are connected with a heavy umbilical cord and the combination weighs 22 pounds. All the connectors on the back are Woo branded and lined up at the same angle. The volume and power knobs are made from solid machined aluminum. The labels for the tubes and the Woo Audio name are all deeply engraved into the enclosure. The sense of solid quality this thing projects is like the audio equivalent of a Rolex. After multiple days of running, it’s barely above room temperature, giving me confidence it will last forever. It is obvious that Woo set out to make an amp built to last a lifetime, which I really admire. Testing Method: Unless stated otherwise my listening on the Woo was primarily with the low impedance (15 ohm) output since most of my phones have less than 100 ohms impedance. The exception being the HD6XX at 300+ ohms. My evaluation method was as follows: I listened exclusively to the WA6-SE for a week and simply enjoyed myself. Then I listened to my Lyr 3 and made note of the differences. After that I put together a list of some of my favorite music for the week and switched between the amps frequently as I played passages over and over to verify my impressions. My equipment connected to this amp is pretty decent but nothing exotic. Most SBAF members would call it Mid-Fi. Most non-audiophiles would call it extreme audio lunacy, but I’m still under $5K so what do they know? The full chain is Pi2AES transport streaming red book or better, RCA coaxial into a Schiit Bifrost 2, then into a Schiit Saga S so I can switch quickly between my Lyr3 and my WA6-SE with matched volume. I used 4 different headphones: Sennheiser HD6XX with factory pads Mr Speakers Aeon Flow Closed with black filters only Focal Elex with factory pads Focal Clear with factory pads How does it Sound? Initial impression with no break-in and stock driver tubes: Really good. No problems like hum or microphonics. Wetter than the Lyr3 but not by much. Mids are a little more forward but very clear and detailed. Headstage is quite different- further back- more in the audience and less on stage with the musicians. Plenty of power for all my phones. After less than 50 hours of break-in, detail and dynamics are excellent. Better than the Lyr with some headphones. A reduction in sibilance compared to the Lyr 3. It’s got a little more air on top than the Lyr with similar levels of clarity. None of that really matters though because the differences are not significant enough for me to choose one amp over the other. What does matter is that it just sounds good. What my Bifrost 2 did to the bass, the Woo does to the midrange. It sounds fuller, more musical, more euphonic, more real. Additionally, the imaging is excellent- better than the Lyr 3 with my favorite tube. The timbre is pretty much neutral, though the 15 ohm output impedance did cause my Clears a bit of bloom in the bass. Percussion is outstanding. Woo recommends a 150 hour break-in so further improvement may occur but I didn’t notice much change past 50. Impressions with different headphones: Focal Clear- this is my favorite headphone with the Lyr 3 because of its clarity, resolution and dynamics but it can be a little dry and analytical. Compared to the Lyr 3, the Woo emphasizes and adds some cloudiness from upper bass the down to the low bass. The result is a warmer signature with a touch of bloom. The Lyr 3 is less colored and sounds clearer and cooler and with a little sibilance. The Woo is less fatiguing at moderately loud volumes. Bass is where the Lyr outperforms the Woo, though the Woo has better micro dynamics, mids detail and separation, not to mention imaging. Both avoid the metallic character Focals (and Aeons) sometimes exhibit. Focal Elex- Similar to the Clear though I prefer the Elex- tighter bass with no perceptible bloom. I suspect if the Clear were a little higher impedance the overall sound signature would be extremely close. The Elex synergizes with the Woo very well and delivers a little more clarity than the Clear. If you’re looking for clarity, detail, dynamic detailed bass, great imaging and sweet mids it’s a great pairing that exceeds the Lyr 3 / Elex combo and IMHO the Woo / Clear combo. Sennheiser HD 6XX- This is a headphone that sounds much better on the Woo than a $200 headphone should. It’s not as technically capable as the Focals or Aeon, but when powered by the Woo it’s strengths are on full display.The HD-6XX is relaxing and euphonic with both the Woo and the Lyr 3 but the Woo makes the excellent mids of the 6xx really shine. I tried both the high impedance and low impedance outputs on the Woo and I prefer the low impedance which to me sounded clearer and more resolving. Compared to the Lyr 3, the 6XX stage feels further away and larger. The treble is laid back so definitely not recommended for treble heads but it is extremely forgiving of recording quality. MrSpeakers Aeon Flow closed- This one was a surprise to me. I expected the high current / low impedance nature of the Aeon would make the all tube WA6-SE struggle, but it didn’t do too bad. The sub bass is rolled off a few dB and the bass isn’t as energetic as the Lyr, but that would be about my only complaints. Compared to the Lyr 3 the WA6-SE brought detail, micro dynamics and bigger soundstage plus it pushed forward the mids and added lushness while keeping the treble sparkle and the super black background. The bass sounds a little polite and the imaging isn’t as pinpoint as the Focals, but the end result is a slightly warm musical headphone with great imaging that delivers exceptional mids, clarity and detail. I’m thinking that a higher impedance planar like LCD-2 would probably sound fantastic on the Woo. In summary: The Woo is pretty new so I’m sure there’s a fair bit of “new toy syndrome” in my impressions, but without a doubt; it’s a great sounding amp and I’m surprised there isn’t more discussion about it. It has all the expected benefits of a good tube amp (sweet sound, great mids, great imaging and soundstage) and it sacrifices very little to get there (slightly rolled off sub bass). Also, it’s exceptionally well made for the price. It costs a lot more than the Lyr 3, but it wouldn’t surprise me if all the price difference is in the case. I don’t personally find the case any more attractive than the Lyr 3, but I appreciate the attention to detail and obvious quality. It’s pretty clear you’re getting your money’s worth. The Lyr 3 and WA6-SE sound quite different from each other. The Lyr 3, being a tube hybrid, has less SET tube character but delivers all the bass, energy and drive you would expect of a high power solid state amp and it adds exceptional clarity and a little tube magic on top. IMHO it’s a great choice for headphones that can take advantage of its clarity and excellent bass. It will drive just about anything well which makes it very flexible. The WA6-SE brings traditional tube sound without compromising technical performance much, exceeding the Lyr 3 in layering, imaging and micro dynamics. It has a lush, musical sound that plays reasonably well with all my headphones, but it prefers working against moderate to high impedance. It’s 2W output and 15 ohms of impedance can handle a fairly wide range of headphones, but not all (low impedance and low efficiency is not a good combo). It’s a good partner for analytical headphones that might be a little dry and / or bright. Am I happy with this amp? Absolutely. The quality of construction is through the roof and it delivers a beautiful tube sound that is a true pleasure to listen to. I consider it a total bargain for the price. I haven’t heard any other transformer coupled SET amps so I can’t compare it to the competition, but it absolutely holds its own with my Lyr 3. It’s probably not the best choice if you’re into tube rolling given the lack of information on 13Dx tubes, but the stock driver / power tubes sound great and if you do roll em, prices are reasonable. Highly recommended.