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Crack;Bottlehead OTL - Page 243

post #3631 of 6122

Sorry I couldn't be more help...

 

I've never heard of the tubes you bought, and I don't know if there is harm in trying them.  Hopefully someone here has an answer.  Or you could ask Doc B.

post #3632 of 6122
Quote:
Originally Posted by bigfatpaulie View Post
 

ROP-IN EQUIVALENTS

Input Tubes (Original: 12AU7)

12AU7(A)(WA)
ECC186
ECC82
ECC802(S)
E8025
E82CC
CV4003
CV4122
CV491
5814(A)
6189(W)(WA)
6680 (WL6680)
6067
7489
7316
5963 (computer version of 12AU7)

Sort-of-Drop-In (but not equivalent - for best results, replace plate resistors with Speedball boards)

E80CC
12BH7

Power/Output (Original: 6080)

6AS7G
6080
6H13C
5998
7236
6N13

 

I stole that from a great thread on the Bottlehead forum.  It's well worth a read.


Link to the thread?

post #3633 of 6122
Quote:
Originally Posted by DutchGFX View Post
 

Can I substitute in a 5U4GB, a 6BL7, a 6SR7GT, a 6SK7GT, or a 6SN7GTB into the power tube slot on my Crack? I was at an antiques store and bought a box of tubes for $40, these all fit, but not sure if they are substitutes.

 

Also, for the smaller tube (input?)

Will these fit?

6R39

12AT7

6AU6

6CB6

6C4


The 6SN7 can function in place of the 12AU7 with an adapter, or with a metal punch and a new socket.

The amp could also be redesigned for the 6BL7 with some effort.

 

The rest of the tubes are kind of a hodge podge, thought the 12AT7 is still commonly used in other audio related tube gear.

post #3634 of 6122
Quote:
Originally Posted by ben_r_ View Post
 


Link to the thread?

 

http://www.bottlehead.com/smf/index.php?topic=663.0

 

(I *think* I am allowed to post it...  If not, sorry mods)

post #3635 of 6122

Just following up the above - many of us who have purchased 6sn7 adapters have been badly disappointed by resulting noise issues, so caveat emptor.  I've tried 2 different adapters, and I believe adam tried 3 in his frankencrack, and all of them introduced substantial noise - enough to really make you appreciate how dead quiet the crack is with a 12au7 or 12bh7 up front.  It has been suggested that this can be resolved by creating a battery supply for the 6sn7's heaters (which receive ac from the crack psu), but I haven't seen anyone post confirming that this worked for them.      

 

For further reference, the folks complaining of noise with 6sn7 adapters all seemed to be hd800 users, so this may or may not be less of an issue with other headphones.

post #3636 of 6122

Yeah, you can buy a 6-6.3V DC wall wart (Be sure it's 300+mA), then clip the wires going from B7/B8 to the 9 pin socket, then splice in your adapter to heat the 9 pin tube.  It's also helpful to ground one of those incoming wires as well.

post #3637 of 6122
I have matching pair of 6SN7 I bought from eBay and seller claims they are made in 1944-5 and adapter I bought from local member and had no noise problems driving HD700
post #3638 of 6122

Here is another thread discussing power tubes:

 

Multi 6080 / 6AS7 review

post #3639 of 6122
Quote:
Originally Posted by skeptic View Post
 

Just following up the above - many of us who have purchased 6sn7 adapters have been badly disappointed by resulting noise issues, so caveat emptor.  I've tried 2 different adapters, and I believe adam tried 3 in his frankencrack, and all of them introduced substantial noise - enough to really make you appreciate how dead quiet the crack is with a 12au7 or 12bh7 up front.  It has been suggested that this can be resolved by creating a battery supply for the 6sn7's heaters (which receive ac from the crack psu), but I haven't seen anyone post confirming that this worked for them.    

 

For further reference, the folks complaining of noise with 6sn7 adapters all seemed to be hd800 users, so this may or may not be less of an issue with other headphones.

 

Thanks skeptic I did not know of noise issues with the 6sn7.


Edited by JamieMcC - 1/26/14 at 3:43pm
post #3640 of 6122

Got my shipping confirmation last Friday. Now I only have to by some equipment to build it together. I am eager to do this on a weekend. :)

post #3641 of 6122
Quote:
Originally Posted by Shaldome View Post
 

Got my shipping confirmation last Friday. Now I only have to by some equipment to build it together. I am eager to do this on a weekend. :)

 

 

Good luck! Let us know how it ends :beerchug: 

post #3642 of 6122
Quote:
Originally Posted by Shaldome View Post
 

Got my shipping confirmation last Friday. Now I only have to by some equipment to build it together. I am eager to do this on a weekend. :)

When did you place your order?  Are they still backed up?

post #3643 of 6122
Quote:
Originally Posted by cswann1 View Post
 

When did you place your order?  Are they still backed up?

I also received my shipping confirmation last Friday; ordered on 25th December (Christmas present to myself).

 

Looking forward to join the club and my first real DIY project!

post #3644 of 6122
Quote:
Originally Posted by lolovitch View Post
 

I also received my shipping confirmation last Friday; ordered on 25th December (Christmas present to myself).

 

Looking forward to join the club and my first real DIY project!

 

Congrats to you as well!! You'll love it.

 

@lolovitch and @Shaldome it's worth heading over to the Bottlehead forums if you need any help with your kits. As good as the community here is, there are some real specialists for DIY stuff over there.

post #3645 of 6122

For anyone looking, Frys has the Hakko FX-888D on sale for $70 free shipping. Best deal youll find anywhere on a very nice soldering iron. This is the lowest I ever recommend to anyone serious about soldering. LINK

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