Tube Rolling w/Crack

[skyfail]

Guys I am using a 12au7. Brand cant figure out.
Maybe a Slyvania JAN CHS 12AU7
So the issue is the tube is working fine when music is on.
But when the music is off,the tube is making grrrrrrrrrrrrrrrr noise on the left channel.
Any tips ?

Let me know.

[mcandmar]

Guys I am using a 12au7. Brand cant figure out.
Maybe a Slyvania JAN CHS 12AU7
So the issue is the tube is working fine when music is on.
But when the music is off,the tube is making grrrrrrrrrrrrrrrr noise on the left channel.
Any tips ?

Let me know.

Make sure the tube pins are nice and clean, remove any oxidization etc.  It may just be a noisy tube.

[mcandmar]

I found a few 12au7 variants that dont break the bank and might be of interest to Crack owners,

http://www.ebay.co.uk/itm/310139224510?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT RFT from what i have read were made in East Germany, odd looking plates in them but they are astounding good little tubes, nice deep low end extension too.

http://www.ebay.co.uk/itm/271159045585?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT Seller claims they are Brimars which i can believe as i always liked the Brimar ECC82. 13D5A was some weird UK military spec, its a bit like a 5963 or 5814.

http://www.ebay.co.uk/itm/5963-12AU7-ECC82-SYLVANIA-SQUARE-GETTER-NOS-TUBE-VALVE-/271428375357?pt=UK_Sound_Vision_Valves_Vacuum_Tubes&hash=item3f3264533d My favorite of the murican tubes, i have a few with "US Army" written on them in Gold text, very clean sounding.  A close 2nd to them would be the RCA Clear tops.

The same seller also sells Brimar, Mullard, and Telefunken 6211's for as much as those three together.  Personally i prefer clean and clear sounding tubes, i actually really dislike the Mullard ECC82 as i find it dull and muddy sounding which the same seller lists at £42. Buy these three instead

[pduk]

I'm listening to Tori Amos "Unrepentant Geraldines" right now on the RFT valve (yes, I couldn't resist) having swapped out my RCA clear top. The power valve is the standard tung sol 6080. Well... the kick drum is really kicking, the bass is throbbing, and it still sounds pleasantly bright which was one of the reasons for using the RCA, to lift the top end a bit on the 650 headphones. So, a good call so far, thank you. 12 quid well spent

Paul.

[danw]

Hello,

I'm new in to the tubes and Crack world. What do you guys think about this tube?

h ttp://www.ebay.co.uk/itm/Vintage-Western-Electric-421A-5998-STEREO-TUBE-Shorted-/400802730381?pt=Vintage_Electronics_R2&hash=item5d51b4518d

Is this the same tube as a Western Electric 421A???

Is this a good choice? Thanks.

[Chris65]

Avoid. Says it is shorted, so will not work. He's only selling it as a display piece, otherwise it would cost a heck of a lot more.

[danw]

Thanks for warning me.

[JamieMcC]

Those GEC's are exceptionally nice sounding tubes.

[Adrian]

Correct JamieMcC on the GEC 6AS7G.
When I replaced the Mullard 6080WA (rebranded Philips - made in Mullard Mitcham plant) the HD600s came alive and the 4AAs got markedly better.
The combination of the 6AS7G and the Cleartop work well with both of these cans.
If I had a brighter headphone, say a Beyerdynamic, I would probably have to go back to the 6080 or most likely just replace the Cleartop with a Mullard CV4003 to cut back on the top end sparkle of these cans.

[JamieMcC]

Correct JamieMcC on the GEC 6AS7G.
When I replaced the Mullard 6080WA (rebranded Philips - made in Mullard Mitcham plant) the HD600s came alive and the 4AAs got markedly better.
The combination of the 6AS7G and the Cleartop work well with both of these cans.
If I had a brighter headphone, say a Beyerdynamic, I would probably have to go back to the 6080 or most likely just replace the Cleartop with a Mullard CV4003 to cut back on the top end sparkle of these cans.

I ran the GEC with the Mullard cv4003 for some time its one of my three favourite tubes and a very nice combination with the GEC and my Beyerdynamics. The others being the Tungsram E80cc with the speedball switchable resistor modification and a black glass National Union 6sn7 gtb with a adapter.

[John EH]

Correct JamieMcC on the GEC 6AS7G.
When I replaced the Mullard 6080WA (rebranded Philips - made in Mullard Mitcham plant) the HD600s came alive and the 4AAs got markedly better.
The combination of the 6AS7G and the Cleartop work well with both of these cans.
If I had a brighter headphone, say a Beyerdynamic, I would probably have to go back to the 6080 or most likely just replace the Cleartop with a Mullard CV4003 to cut back on the top end sparkle of these cans.

It's funny you mention the Cleartop because I have all manner of 12AU7 and always found the clear tops to be not so great in other audio gear, however they are exceptional in the Crack.  I am currently running the CV4003 though.  But my other Crack has a clear top in it.  It a fine synergistic match for some reason or another.  Again, not so in other gear.

[howzz1854]

i am just wondering, since i am using the crack A LOT now. i'd like to stock up on some stock replacement tubes.

does bottlehead sell them? if not, where are some of the best places to get stock crack tubes.

[JamieMcC]

For many of us ebay is a endless source of tubes for every budget, just search for "6080 tube" or "6as7g" for the driver tube and "12au7" for the input tube.

Have fun.

[Nathan]

I'll 2nd the eBay suggestion. Tons of tubes on eBay. I have a spare set of tubes and I think I paid between $30 and $35 for both tubes with shipping. My spare input is an RCA clear top and my spare driver is a GE 6 as7g.

But as always, it's buyer beware. One tube I bought for $9 was DOA.

[borism]

Another option is to get tubes from a reputable supplier like Brent Jessee (audiotubes dot com). Those are tested and guaranteed not to be DOA. You would be surprised how reasonable the cost is.