[scootermafia]

Well, the Tung-Sol, Electro-Harmonix, and Sovtek 6SN7 tubes from tubedepot.com (they all appear to be new production) are crap.

While they seem to sound decent, they all hum in my new DV336SE.

The Tung-Sol I gave at least 50 hours of break in to, to get it to come around. The other two arrived today but are humming badly right off the bat.

The real irony is that the crappo Chinese generic tube that came with it is the only one with zero noise. It really doesn't sound good (read: my CMOY sounds as good) and I don't want to have to use it.

 

[sentinl]

There is a mod called the fitz mod or something to the same. You install 2 small caps and all hum goes away. Some more experienced members can give you details but it can be a lifesaver for the DV336 i guess.

 

[nikongod]

darkvoices are known for hummmmmmmmmmmming

look up the fitz mods.

 

[atbglenn]

The humming seems to be an ongoing 336i and SE problem. Why hasn't Darkvoice addressed this problem yet?

 

[scootermafia]

This sucks, why does their stock tube work and none of the others sound right? Is there any good tube for these? Or is everyone either fitz modded, using stock tubes, or just enduring the hum?

 

[dunski]

I never had a humming problem with my 336se. I've tried a bunch of tubes on it from Motorola to CBS to tung-sols and sylvanias. The only problem I had was buzzing with some tubes. I had a noticeable loud buzz in one of the channels. I've read that it may indicate a bad tube and that the 336 just doesn't "like" certain tubes.

Either way, the tubes that do buzz are nearly silent.

 

[Tridacnid]

I have only gotten humming or buzzing tubes recently, and with 6F8G's, not 6SN7's. Mine isn't Fitz modded, but I plan to in the near future.

 

[Uncle Erik]

Does the Darkvoice run AC to the filaments? Converting them to DC isn't that hard.

 

[nikongod]

Quote:

Originally Posted by Uncle Erik /img/forum/go_quote.gif Does the Darkvoice run AC to the filaments? Converting them to DC isn't that hard.

It does use AC heater supplies.

its not that hard to float or bias them above ground either.

 

[Dept_of_Alchemy]

I believe some tubes are designed for pulse operation optimized for AC heaters, not sure which 6SN7 are like that though. But like others mentioned, try the Fitz mod or upgrade to another amp.

 

[scootermafia]

Yeah, I just need to figure out if buying more tubes is going to help and hope I get lucky with a higher quality version of what came stock, one with no noise, or whether there's something about all the other non-chinese tubes that makes them hum.

 

[Skylab]

No, it is not all tubes other than the stock ones. About half the tubes I tried in my 336SE buzz/hum, and about half work perfectly. Since I have a large collection of 6SN7-type tubes anyway, this really isn't an issue for me, but buying tubes until you get one that doesn't buzz could be a bummer.

One thing I have noticed, and not sure if it's just luck or what, but all of my true vintage 6SN7GTB's work fine - it's the GT's that were hit or miss. You bought a bunch of current production 6SN7's (none of which I think sound good anyway). Try getting a vintage RCA 6SN7GTB. This won't cost that much, will sound better than any of the tubes you ordered from Tubedepot, and will probably work fine.

 

[Golden Monkey]

Well, those new prod tubes aren't really known to be all that great anyway...