[SMBuscemi]

I have the WA2, and before it was even delivered I got the Tung-Sol 5998s. Love them paired with my Grado PS500s.
 
You have to burn them in. If you're having a hard time finding these tubes, I bought mine from www.VacuumTubes.com and my hard to find Thomson 6111 I got from www.tubezone.net (for my Contintental V2...)
 
Then I got Woo's DAC a month later and talk about a day and night difference! Two songs I know well I streamed on Spotify Hi Res (Van Halen; "Take Your Whiskey Home" and "Could This Be Magic") made the music jump like David Lee Roth was singing right next to me with Eddie playing the acroustic guitar at my office. Jaw dropping. Money well spent.
 
I'm still burning in the Woo Audio WDS-1 but out of the box with cheap Monster cables I borrowed just to hear it, it sounded incredible. (Note: I recently updated to Cardas Clear USB and that was another meaningful incremental improvement.
 
 
For what it matters, i met Jack Woo at T.H.E. Show in Vegas (CES 2013) and he's such a nice, humble guy. So polite. So nice I almost bought the WA7 for "home" use as that sounded really incredible with his test pair of HD-800s (which are notoriously piggy on power). We'll see...
 
At first i was really confused with the WA2. Out of the box, I was sort of dissapointed. I didn't use a DAC. I wanted more. But then I learned that I wasn't using my correct headphones. My HiFiMan HE-500s weren't a good pairing per Jack.
 
Being a newbie, I didn't know this, and make no mistake, I am very happy with my Desktop Setup.

 

[CaffeinatedX42]

I'm moving this entirely from another thread where it was less appropriate (and nobody was replying).
 
 

I had a question to pose to the collective mind about a problem I'm having with my WA2, or really with some tubes on it.  I'm totally new to tube amps.
 
I purchased a set of Tung Sol 7236 NOS power tubes and while they have definitely improved the sound in many ways that I enjoy I'm have two issues.
 
From one of the tubes I am hearing intermittent static.  It does not happen all the time, just randomly, but regularly enough that it occurs for at least a few minutes during each listening session. When this is not happening the tube sounds amazing and is almost completely silent otherwise.  The static happens even without a source plugged in.
 
The other tube started very quiet and near perfect.  Unfortunately after perhaps 16 hours of listening (spread across several four-six hour listening sessions) it has developed a consistent buzz/hum.  The noise starts after about an hour of listening and persists even with the volume turned all the way down, all sources removed, and if I turn the amp off then on.
 
I have tried hd800's, hd650's, and Grado sr125's; the issue happens with all three.
 
When I switch back to the stock tubes (after letting the amp cool down overnight) both issues disappear completely.  The stock power tubes have zero hum or static that I can detect.  They are also, unfortunately, boring compared to the 7236's (to my ears).
 
So the question is: should I give the new tubes more time to "settle in" with the hopes that the issues go away or request a replacement from the vendor?  Is this normal?  

 
I'm realizing now I should have posted this in the WA2 tube rolling thread, oh well.
 
UPDATE:  The vendor has gotten back to me now and says:
"[size=14.399999618530273px]The 7236 is a high gain tube. The noise is much easier to pick up. Compared to the 6080/6AS7, the 7236 noise floor is expected to be higher. The static noise should not occur after some breaking-in."[/size]
 
[size=14.399999618530273px]That makes sense to me, except the hum I hear (which I'm guessing is the noise floor he references) is only audible in one of the two tubes.  If it was both that would seem a more valid explanation.[/size]
 
[size=14.399999618530273px]Any advice?  Is this just the way tubes are, often with one being nice and quiet while the other makes noise, even in a "Hand-pick matched pair"?  As I mentioned above, I'm totally new to this.[/size]
 
[size=14.399999618530273px]UPDATE:[/size]
 
[size=14.399999618530273px]I've switched the sides of the power drivers and the hum came back but stayed on the same side of the headphone (the right side); very strange.[/size]
 
[size=14.399999618530273px]I'm also confused as the volume turned all the way down does not impact the hum; it stays the same at any volume.  Yet as mentioned above when I switch out the 7236 power driver with the stock tube it goes away entirely.  Bizarre.[/size]
 
[size=14.399999618530273px]I'm going to do some more experimentation by systematically switching the sides of the other tubes too.  [/size]
 
[size=14.399999618530273px]In the meantime does anyone have any advice?  I really really like the way the 7236 sounds other than this strange single sided hum.[/size]

 

[HeatFan12]

Well Caffeinated, in switching the power tubes for the stock ones and the noise goes away, it is definitely a prob with the 7236 power tubes.  This- "[size=small]7236 noise floor is expected to be higher"[/size].  That might be the case but they should not experience static and your other noise issues.
 
I would ask about your source, but since the stock tubes are quiet, it's not a source issue.  Some tube amps respond differently to usb input and have a hum sometimes but that is not a tube amp problem and I remedied that issue with a couple of my amps with a usb to spdif converter.
 
I would say run them for a good while non-stop in eight hour intervals and see if the noise diminishes.  Also, if you have it, try and clean the pins with deoxit and pipe cleaners or a firm brush.
 
 
 
Cheers!

 

[CaffeinatedX42]

Quote:

Well Caffeinated, in switching the power tubes for the stock ones and the noise goes away, it is definitely a prob with the 7236 power tubes.  This- "[size=small]7236 noise floor is expected to be higher"[/size].  That might be the case but they should not experience static and your other noise issues.
 
I would ask about your source, but since the stock tubes are quiet, it's not a source issue.  Some tube amps respond differently to usb input and have a hum sometimes but that is not a tube amp problem and I remedied that issue with a couple of my amps with a usb to spdif converter.
 
I would say run them for a good while non-stop in eight hour intervals and see if the noise diminishes.  Also, if you have it, try and clean the pins with deoxit and pipe cleaners or a firm brush.
 
 
 
Cheers!

 
 
Thanks for the informative response HeatFan12!  It seems the issue has now been solved!  

 
I did the following:

• Cleaned the 7236 tubes pins really good with rubbing alcohol (I don't have deoxit handy and Woo Audio's site recommends alcohol so I figured that was an OK alternative).  The pins already looked very clean but I did get a slight big of stuff off one of the tubes (which has a big of discoloring on the base too though NOS.
• Kept the 7236 tubes "reversed" from the original configuration.
• Reversed the driver tubes; which are jj e8cc's (the stock ones).

 
The result was that the right channel hum & the static completely disappeared!  My suspicion is that it was reversing the drivers fixed it since the hum was previously consistently in the right ear even after reversing the 7236's.  Perhaps when reversing it I also scraped off some corrosion or something.  Bizarre though as replacing the power drivers with the stock ones also resolved the issue previously; maybe something about the 7236 and driver tube interaction was causing it;  I have no idea, quite the mystery.
 
I've ran them now for about 15 hours (eight hours yesterday after your e-mail, six hours last night, one hour as of right now today) and the whole time have had no problems.  Very exciting! 
 
Separately, though unrelated, my setup is a Sony cdp-m555es 400 disc CD-changer I've had forever, a Schiit Gungir (connected with optical), and of course the WA2.

 

[HeatFan12]

Glad it worked out Caffeinated and kickass setup you have....Enjoy!!! 

 
Cheers!

 

[Senn-Fi]

Anyone else think the 5998 tubes are too powerful?  I can only get to 4-5 clicks on the volume control of my WA-22 until it gets too loud for my HD-800.  I actually am using the Western Electric 421A's because I found them for $200 for a matched pair of NOS tubes which was cheaper than any of the 5998's I could find. 
 
Any recommendations for a lower power tube that will sound just as good that is easy to find?

 

[Dubstep Girl]

wow thats a great price for them!
 
umm the tung sol 5998 sounds better than the other tubes ive tried 
 
you could look for a GEC 6AS7, though they're really expensive. also the sylvania 7236 should have a bit less gain than 5998, though its almost as powerful as tung sol. i don't know if theres any other tubes that'll sound as good as 5998. you could check out Tung Sol/Chatham 6AS7G though

 

[okw3188]

Been using Siemens E88CC for a long time and just last week thought of trying PCC88 on my WA2. The result is awesome, the soundstage seems to be slightly wider and much stable than E88CC. The only trade-off is that the filament voltage runs on a 7V, instead of a 6.3V.
 
For those who have this tube, give it a try and share your impressions. My output tube is Tung-Sol 5998.

 

[Dubstep Girl]

Quote:

Been using Siemens E88CC for a long time and just last week thought of trying PCC88 on my WA2. The result is awesome, the soundstage seems to be slightly wider and much stable than E88CC. The only trade-off is that the filament voltage runs on a 7V, instead of a 6.3V.
 
For those who have this tube, give it a try and share your impressions. My output tube is Tung-Sol 5998.

 
 
been curious in trying out siemens tubes. i have amperex bugle boys and A frames atm, really good with T1/WA2. 

 

[helljudgement]

I've own the wa2 for nearly 2 months I must say I'm very impressed with what I've heard. Initially with stock tubes the wa2 sounded very good especially coming from my hd600 at that time. Its very smooth and quite laid back sounding. But having upgraded to the 800s a month back I must say the wa2 does seem a bit dull. I've heard the 800 on a burson conductor prior purchasing and I was mighty impressed with its detail retrieval and dynamics. It sounded very good and in fact at that time I was actually hoping that my wa2 could perform just as well albeit a bit smoother on the edge and slightly lusher vocals. But in actual fact the hd800 sounded a bit dull and bland a bit too laid back for my liking which is quite disappointing considering the wa2/hd800 combo is one of the more recommended combo. It lacks that bit of air and the tactile feel that make the 800 sound that much more enjoyable on the burson.
 
I then stumbled upon this thread and many others regarding the wa2 tubes. It seems that there's a general consensus that the wa2 is a capable amp made average by its stock tubes. I could easily find post which states the stock tubes are dull the most recent of which being found on the taboo mkiii thread where mwindham08 compared various driver tubes and stated his wa2 stock tubes were garbage and had to be replaced for it to reveal its full potential. With that I've decided to play around the tubes a little before deciding whether to change my source(which I eventually will) or change the amp.
 
I've ordered a pair of Sylvania 7236 based as it is easier to find than the much coveted TS 5998 and GEC 6as7g. When I roll in the tubes and warm it up for the first time I was very excited as to what differences I'm going to hear. Almost immediately I've noticed that the clarity has increase and there's a bit more air between the instruments. Switching back and forth over the next few hours between the tubes, I realised the 7236 is by no means a huge improvements over the stock 6080 in terms of technicality but the effect the improvements have on the music makes them that much more enjoyable. I was impressed by the change to say the least and I was more than happy to live with this combination at least until I found a pair of reasonably priced driver tubes.
 
While browsing through my local forum a the other day I saw a pair of Siemens e88cc NIB being sold for 158 USD. Now that's something I can't ignore so I contacted the person and the tubes arrived yesterday. The Siemens give the hd800 body and texture that wasn't there before and it improves upon the imaging. I could literally feel the strings being plucked and drums being struck its just so involving not to mention smooth. Can't do any direct comparison between this and the burson I've heard months before but I could safely say this is here to stay for a very long time. And now there's just the rectifier left to settle.
 
With regards to the rectifier tubes I do have one question for experienced wa2 tube rollers though. Will it make much of a difference for this amp? I have read that the rectifier is the least important tube to roll for the wa2 as it does not affect the sound much. Is that true?

 

[Dubstep Girl]

yes they make a bit of a difference. try mullard EZ80 or RFT EZ 80, the RFT are pretty cheap and easy to find a new pair on ebay. it improves transparency and overall smoothness. the stock can be grainy or dull

 

[mwindham08]

Just to be clear I wasn't trashing the WA2 on my review. The WA2 just requires less readily available and/or more expensive tubes to sound it's beat imo

In comparison the decware taboo does not improve as much as the WA2 with tube rolling. They only have the 6DJ8 tubes in common though so maybe that is why.

I'm sure if woo audio could cheaply include tungsol 5998s with every amp they would do so

 

[helljudgement]

Yes it was stated that your views were directed at the stock tubes and not the amp itself. One of the joys of owning the wa2 is figuring which tubes works best for you. Not cheap but very intriguing to hear the way the sound change.

@dubstep girl thanks for your input I see if I could find some cheap nos rectfier and report back my findings when I received them.

 

[Nic Rhodes]

do people prefer 80 or 81?
 

 

[Dubstep Girl]

in general? or the RFT? 
 
i know someone here like RFT EZ81, i've only heard the EZ80.
 
as far as ez80 vs ez81 in general. i think most people prefer EZ80 saying its smoother