Tube Rolling w/Crack

[attmci]

so I was told to try a 6sn7 with one of the Garage1217 adaptors, and it came today with a Raytheon 6sn7gt which extends lower than the stock GE 12au7a and has a wider soundstage, yet with a lot more distortion and a bunch of microphonics, plus I think it looks stupid as the adaptor is misaligned and every 6sn7 seems to look just like a big rod, and a not insignificant part of tubes for me is the look of them so I'm going to try flipping this forward and just getting a better 12au7. I'm looking at moving my power tube from a Philips JAN6080wc to a Sovtek 6as7g, and moving that GE 12au7a to... something. I've heard good things about new tung sols and mullards, though I've heard myths about rca clear tops even if they're a bit pricier, not to mention tung sol's NOS 5998's. can I get any recommendations on tubes to move to? I like a somewhat warm sound (crack and hd650s yea) and the wide soundstage of the raytheon is super fun, tho I also don't like the music to sound too smeary and to retain its detail and punch.

There are a lot of 6SN7GT tubes to roll. I and a couple of others have better luck than you.

Yes, you do need a better power tube. Why not save the $$ on those cheap tubes and go directly to a  Bendix 6080WB and/or a 5998?  BTW, rca clear-top is ss sound, not warm at all. You may like smoke glass TS 12au7.

[JamieMcC]

fwiw the RCA clear top tube can also be easily and cheaply found on ebay branded as CONN just search CONN 12AU7 and any Conn branded 12au7 tubes with clear tops are the RCA made 12AU7 clear top you will find plenty out there for just a few dollars.

[benjet]

Ok, new to this game. Got a crack, like everyone else on this thread. Been rolling some 6as7g's. Found some from Canada. Branded Philips and look exactly like a RCA, sounds a whole lot better... Got another one on order to see if this was just a freak tube or these are something special. I'm hoping on the latter as these only cost $22 delivered to Australia. Also went and bit the bullet and got a 5998. Wow, an amazing sound, so wide and detailed. I'm running some LCD-3's and always found the 6as7g sounded a bit muddy in the mid range. The 5998 lifted the lid on this. So endgame solution... I wish...I foolishly when and swapped out the output caps with some axon true caps...2 x 56 mike in parallel per channel. Swapped out the 5998 for my least favourite 6s7g (in case all went wrong and I detonate a tube) and flicked the switch......5 minutes warm up.....then i fed in my favourite test track, not expecting much...I was wrong....lid was off, sound stage wide and detailed. Something this tube had never hinted at being able to do. Well, if that tube could do that, the 5998 was bound to melt my ears. NOT TO BE Poles have flipped, now the 5998 was flat and narrow.It was night and day to what it was. The up side is that I've now put in the Philips tube and am currently picking up my jaw from the floor. It's got everything the 5998 had and more. Mixed emotions at the moment, got a $220 tube that'll sit on the sideline for now, but got two $22 "super tubes". I'm going to put back the stock caps and put a switch in to swap between the them, although i'm confident the axon/6as7 combination is my preferred.

[Paul Birkeland]

When you put new caps in the signal path, I would run the amp for a few hundred hours before altering any other parameters/making additional judgements.

[adydula]

Hello,

I have had my Crack w/speedball for awhile (+year) and have nine amps of all sorts, SS, Tube, DIY etc..

The Crack has always worked well with T1 and T90's here for me.

I did two things in the recent week that has me wondering how much better than this can it get with the cans I have and
the way my Crack is set up.

The Crack is stock parts, only speedball update.

I have a few 6AS7G RCA coke bottle style tubes and several 112AU7's

For the last several months I used the RCA 6AS7G with a Bugle Boy, AMperex 12AU7, my standard.
Well the other day I decided to stick in another set and had a Slyvania 6080WB and a Mil Spec JAN 5963 tube dated 3-71.

I am floored once again on how this tube set is working for me.....for each day since I changed these over I have spent 2 sessions for a few hours each day listening...and thinking after the first listening session this "new" sound will wear off and become well....ho-hum or the same...

Well after 5 days now its still OMG good, holographic and 3d...great recordings are indeed great and each and every tune I play
you can discern and  "hear" inside the recording...

Jut wanted to share this lesser known or used tube? The Slyvania can be had for a low cost on ebay etc...the 5963's I found there as well a few years back bought a bunch of them for the "cheap" all test great on my tube tester.

Enjoy
Alex

[attmci]

When you put new caps in the signal path, I would run the amp for a few hundred hours before altering any other parameters/making additional judgements.

Why it took so long for caps to settle? Thx.

[Paul Birkeland]

I'm not sure that there's any agreement as to what's going on with cap break in, this is just a part of the collective experience of the hobby.

[Kitchener]

I wanted to get for a Mullard for my Crack, so I went to eBay and searched for Mullard 12AU7.
But which one!? There are a million different “Mullards” it seems.

Long Plates.
Grey Plates.
Black Plates.
Clear Tops.
Reissue.

Help cheapskate out!

-not that I need new tubes, I just want a small selection of replacements for posterity.

[Chris65]

You can eliminate two from your list. Mullard never made clear tops & the re-issues are Russian not genuine Mullard.

[JamieMcC]

I wanted to get for a Mullard for my Crack, so I went to eBay and searched for Mullard 12AU7.
But which one!? There are a million different “Mullards” it seems.

Long Plates.
Grey Plates.
Black Plates.
Clear Tops.
Reissue.

Help cheapskate out!

-not that I need new tubes, I just want a small selection of replacements for posterity.

You are probably looking for the mullard 12au7 box plate (CV4003) its probably the best of the bunch without getting into silly money. Do a bit of googling on it.

[Paul Birkeland]

Help cheapskate out!

As a fellow cheapskate, you can find a lot of tubes with printing on them that's pretty generic, but that are genuine Mullard tubes.  This is the kind of auction I'd look for:

https://www.ebay.com/itm/3-WEBCOR-IEC-MULLARD-BRITAIN-12AU7A-ECC82-VTG-Vacuum-Tube-RADIO-GUARANTEED/263488316290?hash=item3d5920a382:g:pn4AAOSwogpaXkHV

The one with the red printing looks to be American, but the other two are certainly Mullards. 

[JamieMcC]

As a fellow cheap skate finding premium tubes on ebay at low/reasonable prices due to slightly strange listing headers was always a buzz when I was running my Crack.

I spotted this listing today that might be of interest.

https://www.ebay.co.uk/itm/2-6080-valves-tubes-1-GEC-1-GE-avo-tested-Free-worldwide-ship/232669681200?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

[Kitchener]

As a fellow cheapskate...

The one with the red printing looks to be American, but the other two are certainly Mullards. 

As a fellow cheap skate...

Cheapskates unite!

I assume it takes half a lifetime's worth of experience to tell one type of tube from another like that, Paul.
But are there some pointers you can share or online sources you can recommend that can teach an absolute neophyte like me how to tell what's what?

You are probably looking for the mullard 12au7 box plate (CV4003)

I'll give those a look, thanks!

You can eliminate two from your list.

Good!
I've mostly heard Reissued tubes muttered in the same breath as Sauron and Voldemort, so I tend to give those a long look down the nose.
Though this snobishnes has not been earned through experience, just reading forum posts, I'm worse than a hipster! 
Are all reissues shit?

[Kitchener]

I don't know if this is strictly adherent to the rules of this thread, but I'm dying to tell someone and I didn't know where else to post this.

So I built by Crack over the weekend.
Such a fun project! (apart from mouting that god damned transformer and those sodding 6-lug terminals!)
And I just have to share my first experience with tube rolling!

Anyway, I'd already ordered a set of Clear Tops and a set of 6H13Cs (Svetlana, I think), and my Crack came with a Clear Top and a 6080 Philips tube.
I'm aware tubes and components need a substantial burn-in period before you get their best performance, but I could stop myself from switching between the 6080 and 6H13C.

And today at the office I was first listening with the 6H13C (I just really like the massive bottle look of these!) but after a while I started finding the high notes (symbals and such) a little too sharp.
So I swapped in the 6080 and the sharp edges were gone!

Of course you men-of-the-world know this, but for a simpleton like me this excited me greatly!

[Paul Birkeland]

I assume it takes half a lifetime's worth of experience to tell one type of tube from another like that

The seams in the top glass can tell you a fair bit about where the tube may be from (and isn't from for that matter).