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Sophia 274B meshplate

post #1 of 10
Thread Starter 
Please tell me I didn't just throw out $160.00. I just ordered the Sophia 274B mesh plate for my WA6. Thing is I have a very early WA6 late 2007 I think. From what I'm piecing together here, it may not work correctly do to the first Capacitor after the rectifier needing to be 10uf. I'm wondering if mine is using a higher maybe 20uf. How can I find out? Does anyone here have an early product run, who's using the Sophia 274B Mesh plate? I should have made sure of this before I ordered it on WooAudio's site. The reason I'm suspicious, is because on their tube chart it says the WA6 is not compatible, yet they offer it as an upgrade. This makes me believe they may have changed something along the way. Any input would be great. Thanks.
post #2 of 10
Thread Starter 

Nobody?

post #3 of 10

I think all WA6 are using 330uf as first capacitor. It's the capacitor in the middle of the board located near the transformer at the back held by zip tie and glue. The label is hidden by positioning it towards the board.

I've stopped using the Sophia after I learned of this. Some say you can get away with it since it's drawing only small current but I think it's still not a good idea. You can't lower the value because of hum issue.

post #4 of 10
Thread Starter 
Quote:
Originally Posted by clowkoy View Post

I think all WA6 are using 330uf as first capacitor. It's the capacitor in the middle of the board located near the transformer at the back held by zip tie and glue. The label is hidden by positioning it towards the board.
I've stopped using the Sophia after I learned of this. Some say you can get away with it since it's drawing only small current but I think it's still not a good idea. You can't lower the value because of hum issue.

Why do they sell it on their site as an upgrade for the WA6 then? That's pretty misleading. Did it seem to work alright? How did it sound. Why did you stop using it, and what year was your amp built? I'm contacting them first thing tomorrow. Supose it can really impact the life of the tube.
post #5 of 10
Quote:
Originally Posted by tony3d View Post


Why do they sell it on their site as an upgrade for the WA6 then? That's pretty misleading. Did it seem to work alright? How did it sound. Why did you stop using it, and what year was your amp built? I'm contacting them first thing tomorrow. Supose it can really impact the life of the tube.


It worked fine and sounded good. I only had it for about =30-40 hrs. It's built in '11. Some brands of 274B would even spark on start-up. It will definitely shorten its lifespan.

From sophia website:

Note(*): 274B is direct heating tube. The indirect heating 5AR4 may turn on slower, however, people who buy 274B is for its superior sonic performance. To fully utilize its benefits, it may require first stage capacitor (capacitor input) to be less than 10MFD, or would shorten the 274B life span (very much like smoking is bad for your health). It would not be a problem with common choke input. Please consult to your amplifier maker or refer to a tube manual. This 274B is an update of the NOS WE 274B, so both share with same characters. In 1930s, WE 274B was the rectifier choice for 300B single ended theater amplifier in the US.

Please let us know of Jack's reply but I'm sure he'll say it's fine.

It's the reason I'm selling it.

post #6 of 10
Quote:
Originally Posted by clowkoy View Post


It worked fine and sounded good. I only had it for about =30-40 hrs. It's built in '11. Some brands of 274B would even spark on start-up. It will definitely shorten its lifespan.

From sophia website:

Note(*): 274B is direct heating tube. The indirect heating 5AR4 may turn on slower, however, people who buy 274B is for its superior sonic performance. To fully utilize its benefits, it may require first stage capacitor (capacitor input) to be less than 10MFD, or would shorten the 274B life span (very much like smoking is bad for your health). It would not be a problem with common choke input. Please consult to your amplifier maker or refer to a tube manual. This 274B is an update of the NOS WE 274B, so both share with same characters. In 1930s, WE 274B was the rectifier choice for 300B single ended theater amplifier in the US.

Please let us know of Jack's reply but I'm sure he'll say it's fine.

It's the reason I'm selling it.

 

 

so using 5ar4 is safer/better/"healthier" for the amp and/or the 300b? 

post #7 of 10
Thread Starter 

Tried emailing them several times, but no reply yet. Does anyone have a phone number? I'd really like to cancel this order before it ships.


Edited by tony3d - 7/15/13 at 6:26am
post #8 of 10
Thread Starter 

They did issue my refund. Very pleased. 

post #9 of 10

Did they reply to your email?

post #10 of 10
Thread Starter 

Yes they did, and they were able to stop the order before it shipped.

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