when a tube goes bad, how does it sound?

[danger boy]

Today while listening to the SDA's I noticed the left channel sounded very muddy.. highs were very muted. So i swapped the left and right tubes in my CAL DAC. bam, sure enough.. the muddy highs follows one of the tubes.

It appears to light up, and sound does come from it.. but it's very muddy highs and mids. IS this normal for when a tube bites the big one? I've only had the tubes about 5 or 6 months tops. I'd say.. maybe 150 hours total use on both.

They are 12AX7's Groove tube gold series. One sounds just dandy, while the other one really sounds bad. I guess there could also be a problem with the DAC, but since it follows the tube. it makes me pretty sure it's the tube.

[Early B.]

Yep, that's the nature of tubes. It's a good idea to always keep spare tubes handy.

[F1nut]

Other times when a tube goes bad it will cause distortion while others have a complete melt down, which may include blowing up.

[danger boy]

Yep, that's the nature of tubes. It's a good idea to always keep spare tubes handy.

I am learning the hard way. I can't get my hands on any tubes this weekend.. i'd love to have it up and running right now.. I could always bypass the DAC, but when I do that.. I can easily tell that the DAC isn't in the mix.. and it make music sound bad.

Anyone want to sell me a matching pair of 12AX7's?? I can Pay Pal you the money.

[danger boy]

I sold the Mullards I had in my DAC last year.. i didn't like their sound, to laid back for me.. so I sold them to a guy locally. cool. he had never seen any like them either. so i let them go for $15 for both. no biggie.

Well now I find that those Mullards currently sell for $225 a pair! :eek: :eek: :eek:

Damnit, do i feel stupid. I guess the dude that bought my Mullards got one helluva good deal. :p

[disneyjoe7]

Don't you just hate that "Backward Vision" of 20/20?

[beardog03]

I have some almost brand new Mullards for sale..(6sn7gt)

Need to check my stash for 12ax7`s...I may have aq set

I have a butt load of 6922/6dj8`s comming up soon

[madmax]

Hey DB, I'd suggest giving a pair of these a try. I'm loving mine. I'd send you a pair but it would take as long as ordering new ones...
http://www.thetubestore.com/ehx12ax7.html
madmax

[danger boy]

Hey DB, I'd suggest giving a pair of these a try. I'm loving mine. I'd send you a pair but it would take as long as ordering new ones...
http://www.thetubestore.com/ehx12ax7.html
madmax

madmax, thanks for the offer and the info link. I think I will order a couple 3 of those.. and give them a try.. can't beat that price.

Where do you use them, in a pre amp or amp?

[rskarvan]

When a tube goes bad... it sort of sounds like Emenim.

[danger boy]

can I use either one of these tubes for a replacement of 12AX7's?

12au7 or 12bh7

I"m a little leary of using anything in my DAC other than a 12AX7 that it recommends.. but you all know more about tube replacements better than I do.

I don't want to use any tube that's going to kill the DAC. Lord only know how damn expensive it would be to fix this thing. :eek:

[danger boy]

ok. i had to wait all of Sunday and not listen to the SDA's because i was dumb and didn't have spare tubes laying around.

well today I went down to the local pawn shop and bought some Groove Tubes...

Damn, the SDA's love me again. And I love them back. :D I had no idea how really bad they sounded with the left speaker missing about 50% of it's higher end sound. They sound stunning again. :)

[danger boy]

madmax i went ahead an placed an order for those EH ones... i look forward to trying them out.. the Groover Tubes now seem a bit to harsh in the top end.. so maybe the EH will smooth things out.

[danger boy]

madmax, yes the EH tubes did sooth things out in the top end.. these new matched pair of Electro-Harmonix 12AX7-EH are very nice sounding. I think they'll be in use for a long time to come.

thanks for the heads up on em. reasonably priced as well. I love it.