[Odin412]

There doesn’t seem to be a dedicated thread to discuss the excellent and often-overlooked (it seems) Woo Audio WA3 amplifier, so I thought I’d start one. I hear the WA3 is being discontinued by Woo Audio, which is a shame. The WA3 is a great amplifier for the right headphones.
The WA3 is a single-ended triode amplifier, so it doesn’t have an output transformer. This makes it suitable for high-impedance headphones like the Sennheiser HD 650 and ZMF dynamic headphones like the Atticus and Aeolus. The WA3 isn’t designed for lower-impedance headphones like most planar magnetics, although I’ve heard of people who have used it for those kind of headphones with good results. I’ve used it with my Focal Elear with good results, at least for some power tubes.
Speaking of tubes, the WA3 can use a variety of tubes, including 6080 and 6AS7 for power tubes and 6922 and 6DJ7 for driver tubes. These tubes are in pretty good supply at often decent prices, especially for the power tubes.
Currently, I’m using a Sovtek 6AS7G power tube and Brimar E88CC driver tubes with good results.
Although the WA3 doesn’t work with every headphone out there, it’s quite special with the right headphones. I love the way this amp sounds with the HD 650, the ZMF Atticus and Aeolus. The WA3/Aeolus combo sounds especially beguiling to me.
Hopefully Woo Audio will reconsider discontinuing the WA3 – it’s a great amp and deserves to be enjoyed by many people.

 

[kkrazik2008]

I recently picked up a WA3 and the tubes it came with don’t seem to be jiving well. It has a Ge 6AS7G for the power tube, and Westinghouse 6922 for the drive tubes.

Any good recommendations on replacement tubes? I thought about picking up the Winged C for power, and a pair of JAN 6922s

 

[Odin412]

I recently picked up a WA3 and the tubes it came with don’t seem to be jiving well. It has a Ge 6AS7G for the power tube, and Westinghouse 6922 for the drive tubes.

Any good recommendations on replacement tubes? I thought about picking up the Winged C for power, and a pair of JAN 6922s

I currently use Brimar E88CC drivers and a Sovtek 6AS7G power tube and I like that combo. I have some notes regarding various tubes that I've tried. Let me dig around and see if I can post some info.

 

[kkrazik2008]

I currently use Brimar E88CC drivers and a Sovtek 6AS7G power tube and I like that combo. I have some notes regarding various tubes that I've tried. Let me dig around and see if I can post some info.

That would be awesome! Thank you Very much.

 

[Odin412]

That would be awesome! Thank you Very much.

No problem! I've added my notes below. Please keep in mind that I'm very treble-sensitive when reading my impressions. YMMV, as always.

Here are the driver tubs that I've tried:

Driver Tube ​	Sound Impressions ​
6DJ8 (stock) ​	Lush midrange; smooth treble; warm sound; a bit dark but very seductive ​
Telefunken E88CC (new) ​	Extended treble; smooth midrange; a bit too bright ​
Electro-Harmonix 6922 Gold ​	Smooth treble; very pleasant and not bright ​
JJ E88CC / 6922 Gold ​	Smooth and pleasant ​
JAN-Sylvania 6DJ8 (vintage 70s) ​	Good bass, liquid midrange, smooth treble ​
Genalex - Gold Lion E88CC ​	Bold and vivid midrange; smooth treble ​
Matsushita 6DJ8/ECC88 1960’s - 1970's ​	Smooth and pleasant ​
Tesla ECC88 / 6DJ8 Dual Triode Yellow Label 1960's ​	Smooth and pleasant ​
Amperex Bugle Boy 6DJ8 "Butt Ugly" ​	Liquid and vivid midrange; smooth, extended treble that's not bright ​
Mullard 6DJ8 ​	Liquid and vivid midrange; smooth, extended treble that's not bright ​
GE 6DJ8 ​	Smooth and pleasant ​
Brimar E88CC ​	Good bass, liquid midrange, smooth treble ​
JSC Voskhod 6H23p ​	Deep and juicy bass, liquid midrange, extended treble with slight sibilance ​

And here are the power tubes:

Power Tube ​	Sound Impressions ​
GE 6080 ​	Very nice and pleasant ​
RCA 6AS7G ​	More open midrange ​
Sylvania 6AS7G ​	Very nice and pleasant; open, extended treble that's not bright ​
GE 6AS7G ​	Very nice and pleasant; good bass; open midrange; smooth treble; slight background noise ​
Raytheon 6AS7G ​	Very nice and pleasant; open midrange; smooth treble ​
GE 6AS7GA JAN ​	Nice and pleasant; lifelike midrange; softer treble; one-time loud scratching sound ​
Tung-Sol 5998 ​	Very nice and pleasant; good bass; open midrange; smooth treble that is very slightly bright ​
Mullard 6080 ​	Very nice and pleasant; good bass; rich, liquid and vivid midrange; smooth treble ​
Chatham 2399 ​	Very nice and pleasant; good bass; rich, liquid and vivid midrange; smooth but slightly elevated treble ​
Sovtek 6AS7G ​	Very nice and pleasant; good bass; rich, liquid and vivid midrange; smooth treble ​

 

[kkrazik2008]

No problem! I've added my notes below. Please keep in mind that I'm very treble-sensitive when reading my impressions. YMMV, as always.

Here are the driver tubs that I've tried:

Driver Tube ​	Sound Impressions ​
6DJ8 (stock) ​	Lush midrange; smooth treble; warm sound; a bit dark but very seductive ​
Telefunken E88CC (new) ​	Extended treble; smooth midrange; a bit too bright ​
Electro-Harmonix 6922 Gold ​	Smooth treble; very pleasant and not bright ​
JJ E88CC / 6922 Gold ​	Smooth and pleasant ​
JAN-Sylvania 6DJ8 (vintage 70s) ​	Good bass, liquid midrange, smooth treble ​
Genalex - Gold Lion E88CC ​	Bold and vivid midrange; smooth treble ​
Matsushita 6DJ8/ECC88 1960’s - 1970's ​	Smooth and pleasant ​
Tesla ECC88 / 6DJ8 Dual Triode Yellow Label 1960's ​	Smooth and pleasant ​
Amperex Bugle Boy 6DJ8 "Butt Ugly" ​	Liquid and vivid midrange; smooth, extended treble that's not bright ​
Mullard 6DJ8 ​	Liquid and vivid midrange; smooth, extended treble that's not bright ​
GE 6DJ8 ​	Smooth and pleasant ​
Brimar E88CC ​	Good bass, liquid midrange, smooth treble ​
JSC Voskhod 6H23p ​	Deep and juicy bass, liquid midrange, extended treble with slight sibilance ​

And here are the power tubes:

Power Tube ​	Sound Impressions ​
GE 6080 ​	Very nice and pleasant ​
RCA 6AS7G ​	More open midrange ​
Sylvania 6AS7G ​	Very nice and pleasant; open, extended treble that's not bright ​
GE 6AS7G ​	Very nice and pleasant; good bass; open midrange; smooth treble; slight background noise ​
Raytheon 6AS7G ​	Very nice and pleasant; open midrange; smooth treble ​
GE 6AS7GA JAN ​	Nice and pleasant; lifelike midrange; softer treble; one-time loud scratching sound ​
Tung-Sol 5998 ​	Very nice and pleasant; good bass; open midrange; smooth treble that is very slightly bright ​
Mullard 6080 ​	Very nice and pleasant; good bass; rich, liquid and vivid midrange; smooth treble ​
Chatham 2399 ​	Very nice and pleasant; good bass; rich, liquid and vivid midrange; smooth but slightly elevated treble ​
Sovtek 6AS7G ​	Very nice and pleasant; good bass; rich, liquid and vivid midrange; smooth treble ​

This is Gold!
thank you again
I am a bit treble sensitive too, aggravates my tinnitus.

Are there different versions of the GE 6AS7G? Feel like mine is underwhelming

 

[Odin412]

Are there different versions of the GE 6AS7G? Feel like mine is underwhelming

I'm by no means a tube expert, but most of the vintage tubes were manufactured over a period of many years (several decades in some cases), so it's not unlikely that there will be differences between tubes made at different times, or perhaps at different factories over the years. I like to try different tube brands to see how they sound - sometimes the difference is small, other times it's easily audible. It' all part of the tube rolling adventure.

 

[kkrazik2008]

I picked up a few tubes over the weekend and something weird is happening. First I found a Chatham 6080WA, and it didn’t work and immediately started to red-plate so I chalked it up to a bad tube. I found a Tung Sol 7236 for a good price, it seems good and definitely indicated that the GE 6AS7 GA that came with the amp was the cause of the noise issue.

Fast forward to yesterday and I remembered my hybrid amp has a pair of Voskhod 6N23P, so I pull them out and put into the WA3. High pitched noise from each speaker, and the tubes are all visibly brighter. I take them out put back the JAN 6922 and the high pitch noise is gone. I asked Woo Audio if there was a bias issue, they didn’t respond. Have you had any issues like that before?

 

[Odin412]

Fast forward to yesterday and I remembered my hybrid amp has a pair of Voskhod 6N23P, so I pull them out and put into the WA3. High pitched noise from each speaker, and the tubes are all visibly brighter. I take them out put back the JAN 6922 and the high pitch noise is gone. I asked Woo Audio if there was a bias issue, they didn’t respond. Have you had any issues like that before?

Sorry, I don't have any experience with the Voskhod 6N23P. I don't see them listed of the tube list for the WA3 however - are they the same as the 6N1P, which is on the list?

 

[kkrazik2008]

According to some online tube stores they are the same as the 6H23p, where the cryllic translation of H is N. The folks at Woo were not helpful, they suggested I contact the tube seller. Some of the 6922 equivalents on your table are hard to come by, like the Mullard and Brimar. I may go with the Genelex since they are affordable and readily available.

 

[gimmeheadroom]

@CaptainFantastic

 

[Odin412]

Some of the 6922 equivalents on your table are hard to come by, like the Mullard and Brimar. I may go with the Genelex since they are affordable and readily available.

Yes, the Genelex is a new-production tube that's widely available. There's also a pretty good supply of vintage 6922s that you can try, often at reasonable prices - unless you're hunting for original Amperex Bugle Boys or Telefunkens, that is.

 

[Wid]

I picked up a few tubes over the weekend and something weird is happening. First I found a Chatham 6080WA, and it didn’t work and immediately started to red-plate so I chalked it up to a bad tube. I found a Tung Sol 7236 for a good price, it seems good and definitely indicated that the GE 6AS7 GA that came with the amp was the cause of the noise issue.

Fast forward to yesterday and I remembered my hybrid amp has a pair of Voskhod 6N23P, so I pull them out and put into the WA3. High pitched noise from each speaker, and the tubes are all visibly brighter. I take them out put back the JAN 6922 and the high pitch noise is gone. I asked Woo Audio if there was a bias issue, they didn’t respond. Have you had any issues like that before?

Glad I came across this post. I ordered the same drive tubes and they are advertised as a direct replacement for the wa3 drivers. Now it makes me wonder

"This is the most desirable version of the Voskhod Rocket 6N23P with one single grid wire and gray shield. These are legendary tubes and many of today's modern production tubes are modeled after them. These are the direct equivalent of 6922, 6DJ8, ECC88, 7308, E88CC."

 

[kkrazik2008]

Glad I came across this post. I ordered the same drive tubes and they are advertised as a direct replacement for the wa3 drivers. Now it makes me wonder

"This is the most desirable version of the Voskhod Rocket 6N23P with one single grid wire and gray shield. These are legendary tubes and many of today's modern production tubes are modeled after them. These are the direct equivalent of 6922, 6DJ8, ECC88, 7308, E88CC."

Have tried them yet? I was confused too, because when Woo did respond they sent me their compatibility sheet and because of translation issues with Russian to English they said it was not compatible, but their sheet has the tube listed. So it makes me wonder, luckily I put them back to use in my hybrid amp where they sound lovely and I know 100% it’s a 6922 tube socket.

 

[Wid]

I haven’t gotten them yet. Suppose to be here this weekend. Makes me a bit nervous to try them seeing your results.