Another reason why it's a must to bias new tubes.

[64Vibroverb]

See post from time to time about is it necessary to bias when replacing output tubes.
Can't be that hard to match a quartet of EL34's I wouldn't think. I had to replace a set of JJ's that had one tube fail after only a few hours. Ordered a set of JJ E34L's and a set of EL34 II's from Tube Depot. Tried the E34L's first and bias 3@35ma, the 4th measured 42ma. Put the EL34 II's in and set 3@35 and the other is 48ma. And no, it didn't matter which socket. All supposedly had a 24hr burn in. Nice. May try TAD next.

 

[Woods]

Congrats.

 

[mickeydg5]

Was it the same socket that had the higher mA reading?

 

[64Vibroverb]

No, always followed the tube.

 

[mickeydg5]

I gotcha; it did not matter which socket.

Those are a good bit out. Will the seller replace?

 

[64Vibroverb]

Called last week about the first set and wanted me to return the "odd" tube. Seems like they'd want the quad to match. May call back tomorrow and tell them I'm returning all for a refund. They've screwed up parts orders also. No one's perfect but this is BS.

 

[MarshallDog]

NO...all new production tubes have issues? Buy from thenTube Store and they will,take care of issues like this. I have had the best customer service ever from them with tubes not biasing up and tubes failing all too soon and they do their best to check tubes before they ship...

 

[Garrett]

Crap happens.

I ordered a matched set of Groove Tube EL34's from Antique Electronic Supply. They sent me two used tubes. They did replace them but no idea how you could send tubes that were clearly very used.

Tube Depot has been good so far for me.

 

[64Vibroverb]

Follow up. Ordered a set of JJ EL34 II's from thetubestore.com. Put them in before heading out to inlaws for Thanksgiving and all measured within 2ma at 475vdc on the plates. They arrived in 3 days also, so looks like I'll be buying my tubes there now.