Tube Rolling w/Crack

[Paul Birkeland]

Yes, of course have him try the other tubes.  Also be sure he isn't using some completely weird headphone that is expecting a lot more power.

[Lesser_green]

Hello fellow Crack lovers! I have been enjoying my crack for about 4 years and added the SB upgrade about two years ago. I wont turn this into a troubleshooting post, but I suspect my stock Phillips JAN 6080WC is having... issues and seems to be getting worse. I figured now was the perfect time to try something new. I really don't have any experience with tubes other than what I received stock (previously mentioned 6080 and what I think is a Westinghouse 12au7).
Skimming this forum and others I thought I might try a 6N13S. I see a few for cheap on eBay but don't want to wait 4-6 weeks for it to arrive from Russia. Looking at thetubestore.com they have more reasonable shipping times but higher prices, which makes sense. They are selling a Russian 6N13S for $26 and a Winged "C" 6N13S for $50. Both descriptions say they were manufactured by SED in St. Petersburg.

My questions are: What is the difference? Is it really just a difference in logo or is there something more than that to justify twice the price? It says production has ended for winged C, but wouldn't that mean the same for the other tube? I have read good things about the =C= but I don't know if the same applies for the Russian 6N13S. Finally, I was thinking of picking up a spare 12au7 while I am at it. Any recommendations for if I should just grab another NOS 12au7 or should I try one of the reissues or a ECC82? I know a lot of it is personal preference, but I am kinda lost and mostly going off the recommendations on the internet. Any insight would be much appreciated! Thanks!

[Paul Birkeland]

For 12AU7s, I would look for random used tubes on eBay that are tested.  Something like this is probably OK:
https://www.ebay.com/itm/284469134007?hash=item423bae82b7%3Ag%3AFZAAAOSww5FhU6ls&LH_ItemCondition=4

Something like this maybe for 6080s:
https://www.ebay.com/itm/144356020207?hash=item219c4a0fef:g:M~QAAOSweYZh0xKC

[HirkEukvic]

So I tried the Winged C manufacture of the 6H13C. Seems to have really low gain (like, I have to crank it up to 80% to hear my music). That's with my DAC volume out fixed. Any suggestions on what to do? The 6AS7GA that came with my kit has such high gain that I can't use it without reducing the volume out from my DAC.

Or is it related to the power tube?

[Paul Birkeland]

The 6080/6AS7 should make very little difference in terms of overall gain.  If you have the Speedball installed, it would be interesting to know the OA/OB voltages on both the big and the small boards with that 6H13C installed, as that may tell you if you have a dead tube.

[HirkEukvic]

The 6080/6AS7 should make very little difference in terms of overall gain.  If you have the Speedball installed, it would be interesting to know the OA/OB voltages on both the big and the small boards with that 6H13C installed, as that may tell you if you have a dead tube.

I haven't installed the Speedball yet. Sure hoping I don't have a bad tube (it was $50 and I'm outside the return period now). Is there any way I can confirm whether the tube is working? It does glow, just really low gain.

[Paul Birkeland]

Well if sound comes out technically the tube is working.

What are the voltages at terminals 1, 5, 7, and 9? 

[HirkEukvic]

Well if sound comes out technically the tube is working.

What are the voltages at terminals 1, 5, 7, and 9? 

1 and 5, 100 volts each
7 and 9, 4 volts each. That's with the winged C tube. As of yesterday with the tube the kit shipped with, everything was in the specified ranges stated in the manual.

[Paul Birkeland]

4V at 7 and 9 would mean you have a very dead tube.  You also shouldn't really be getting any sound of out of the amp.

[HirkEukvic]

4V at 7 and 9 would mean you have a very dead tube.  You also shouldn't really be getting any sound of out of the amp.

Alright, that's kind of what I figured is it's on its way out. The amp itself seems fine with other tubes and I get very minimal sound (if any, it's unpredictable) with the aftermarket tube. Thanks for the help!

[Paul Birkeland]

On its way out would be having your 100V at 1 and 5 and seeing some number slightly above 100 on 7 and 9.  4V is barely alive, does the tube glow well?

[HirkEukvic]

On its way out would be having your 100V at 1 and 5 and seeing some number slightly above 100 on 7 and 9.  4V is barely alive, does the tube glow well?

The weird thing is that it's still glowing visibly. Do I possibly have something miswired?

[Paul Birkeland]

If your amp was miswired, how would it work with your other tube?

[HirkEukvic]

I've confirmed it was the tube at fault. Ordered a very similar tube from the same manufacturer and am hearing a much better gain from it. Whatever the issue is, it's definitely a problem in the one tube.

[mcrushing]

"You just finished the amp," I told myself. "Just relax and enjoy the jams."

"You don't need to read that 160-something page thread of people talking about vacuum tubes, my inner monologue said. "Mellow out. These are not the droids you're looking for."

"Okayyyyy, maybe one peek down the rabbit hole..."

Five minutes later, tracking numbers for five packages from three different countries are in my inbox.

There should be a tubes anonymous hotline.

Oddly, I've owned a Manley integrated for a long time and never been to into rolling. (Probably because exotic EL84s get stupidly expensive when you need 8, matched. But I bought some great sounding new stock Mullards for the inputs and replaced the drivers when one died. Set n' forget.) It's different with the Crack. The stakes are lower and the options and sonic effects seem endless. So far I've treated this a bit like gambling - small bets on used, vintage, possibly-questionable long shots. I'm sure I'll eventually settle down with some spendy NOS's, but for now I'm finding it fun to research oddball OEM versions, which seems like a good way to get a sense of the various name-brand flavors without shelling out too much. I also like the idea of up-cycling a tube someone pulled out of an old church organ. I’d love to hear of any favorite oddballs folks have run across.

I do have one question for PB, if he's read this far. While I wait for stuff in the mail, I have a spare 12bh7AEH (assume the 'EH' is for Electro Harmonix) from the Manley and I've read various opinions on using them. I know you don't recommend using this tube in a stock Crack and recommend some resistor changes in the Speedball Crack, but I'm wondering if you mean "don't-recommend-it-causes-distortion" or "dont-recommend-you'll-blow-your-amp-up"? I'd be pairing it with a Hewlett Packard 6as7g I bought for like $10, if that's relevant. Love your thoughts, or thoughts from anyone else who's tried it on a non-SB crack.

Keep rollin.