[Silent One]

I have been fortunate. My Woo never saw a light show...2,599 hours without incident of any kind, for that matter. Amp design considered, maybe a replacement Sophia fares better. 

 Then too, the Mighty 596 lurks on the horizon as well.

 

[2359glenn]

Quote:

yeah it just happened once while music was playing but then it stopped.
 
it doesn't happen all the time only on start up a little bit and that one time.

This will continue to get worse until the tube finally burns out. Each time it arks it knocks off some of the oxide coating on the filament/cathode making the
tube weaker. As the tube gets more oxide knocked off the cathode it has less airier for emission so it has less to handle the inrush.
  I know that the WA5 and WA22 have a problem with to large a input capacitor after the rectifier causing it to do what yours is doing. not sure about the WA6.
That is why I came up with the 596 if I were you I would remove it and use a 5AR4/GZ34 it can handle the inrush better.

 

[MomijiTMO]

This is why I don't want to get any fancy rectifiers for my future WA5LE.

 

[Silent One]

Quote:

This is why I don't want to get any fancy rectifiers for my future WA5LE.

 
The USAF-596 @ $40 a pop (ok, and up! 

 ) - a pair of these and your audio rig will be down the street! 

 

[Ultrainferno]

Quote:

 
The USAF-596 @ $40 a pop (ok, and up! 

 ) - a pair of these and your audio rig will be down the street! 

 
If you find 10 new buyers, I'll do another sale

 

[San Raal]

Quote:

This will continue to get worse until the tube finally burns out. Each time it arks it knocks off some of the oxide coating on the filament/cathode making the
tube weaker. As the tube gets more oxide knocked off the cathode it has less airier for emission so it has less to handle the inrush.
  I know that the WA5 and WA22 have a problem with to large a input capacitor after the rectifier causing it to do what yours is doing. not sure about the WA6.
That is why I came up with the 596 if I were you I would remove it and use a 5AR4/GZ34 it can handle the inrush better.

 
I had this happen to a Sophia mesh on my WA5. It would glow purple and arc at startup. Eventually the fuse blew and the plates were scorched black. The amp seems to have suffered no ill effects. I had always assumed the tube was slightly gassy.
 
What is the typical input cap the 596 can handle? I couldn't find the 596 datasheet on the web.

 

[Ultrainferno]

Quote:

What is the typical input cap the 596 can handle? I couldn't find the 596 datasheet on the web.

 
I only have this and I posted it before in this thread: http://dl.dropbox.com/u/95311454/United%20Electronics%20Company.pdf:

 

[Silent One]

Quote:

Quote:

 
The USAF-596 @ $40 a pop (ok, and up! 

 ) - a pair of these and your audio rig will be down the street! 

 
If you find 10 new buyers, I'll do another sale

 
Thanks, this will be helpful. When owning a tube amp, one can never have too many options. WooAudio amp owners would be wise to at least audition this tube. I've already sent one of my own USAF-596's out on tour w/adapter. I'm considering a second tour. And if I need an additional 10 buyers for Champagne Truffles, 

 I'll let you know that as well. 

 

[DarknightDK]

I'll be interested in the 596 tubes if there's a mass order.

 

[Silent One]

Some piece of glass...I'm even enjoying the USAF-596 with a custom built OTL amp!

 

[grokit]

Quote:

I have been fortunate. My Woo never saw a light show...2,599 hours without incident of any kind, for that matter. Amp design considered, maybe a replacement Sophia fares better. 

 Then too, the Mighty 596 lurks on the horizon as well.

 
 
Me too. The only tube issue I've ever had was when I was aggressively rolling and my EML 5U4G blew out. But a lot of those tubes were blowing back then, hence the subsequent re-design(s). In that case, no harm because I was able to get a free replacement as I bought it new.
 
My only other tube-related "issue" is all the $ I've missed out on by either not pulling the trigger or by doing so too quickly, as it seems there's always a better deal around the corner on these old light bulbs!

 

[Ultrainferno]

Quote:

I've sent Jack messages many of time at Midnight, only to hear from him via Twitter a couple of hours later around 5am est. Late night or early start for Jack? Either way, it's impressive!

 
I just now got a reply from Jack. I sent him an email yesterday and he replied already, must still be night there

 

[Silent One]

Quote:

Quote:

I've sent Jack messages many of time at Midnight, only to hear from him via Twitter a couple of hours later around 5am est. Late night or early start for Jack? Either way, it's impressive!

 
I just now got a reply from Jack. I sent him an email yesterday and he replied already, must still be night there

 
0500 hours in New York...fast approaching sunrise. I admire his work ethic. I'm highly interested in meeting this cat! Someday...

 

[Silent One]

Quote:

Quote:

I have been fortunate. My Woo never saw a light show...2,599 hours without incident of any kind, for that matter. Amp design considered, maybe a replacement Sophia fares better. 

 Then too, the Mighty 596 lurks on the horizon as well.

 
 
Me too. The only tube issue I've ever had was when I was aggressively rolling and my EML 5U4G blew out. But a lot of those tubes were blowing back then, hence the subsequent re-design(s). In that case, no harm because I was able to get a free replacement as I bought it new.
 
My only other tube-related "issue" is all the $ I've missed out on by either not pulling the trigger or by doing so too quickly, as it seems there's always a better deal around the corner on these old light bulbs!

 
After following the issue of the EML rec's early demise (kaboom!) and talking at length with George (good guy, by the way...), I decided to wait several months and a couple of re-toolings before making the purchase. I had sticker shock to begin with. Once the Glass started shattering across living rooms every where, I really decided to hold on to my money! 
 
At the time, I ended up with the latest revision, Winter 2011. But when the Mighty 596 showed up later that Autumn, the EML Glass got sent to the locker room anyway! 

 

 

[2359glenn]

Quote:

 
I had this happen to a Sophia mesh on my WA5. It would glow purple and arc at startup. Eventually the fuse blew and the plates were scorched black. The amp seems to have suffered no ill effects. I had always assumed the tube was slightly gassy.
 
What is the typical input cap the 596 can handle? I couldn't find the 596 datasheet on the web.

The 596 can handle it better even though it really is the same as a 5U4GB The big thing with the WA5 is the fact that the rectifier filaments are in series running off 10 volts
These filaments are not rated for series operation. This diagram is what Woo audio sent to Jac at jacmusic and his recommendations on fixing the problem but not the fact
that the tubes are in series.

 
 
 Also the 596 has a more exact filament so they handle being hooked in series in a WA5.