Tube Rolling w/Crack

Dr. Toobz · 1209634

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Offline Paul Birkeland

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Reply #1725 on: March 20, 2018, 08:08:23 AM
Let it run overnight and see if that resolves the issue.  Arcing can sometimes be gas in the tube, and getting it nice and hot for a long period of time can resolve the issue.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Doc B.

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Reply #1726 on: March 20, 2018, 09:24:46 AM
The sad reality these days is that a lot of "untested" tubes have been tested. They just failed the test. Caveat emptor.

Dan "Doc B." Schmalle
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Bottlehead Corp.


Offline Kitchener

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Reply #1727 on: March 26, 2018, 10:30:29 PM
The sad reality these days is that a lot of "untested" tubes have been tested. They just failed the test. Caveat emptor.

But have they been double tested?
-or tripple tested even?
It is the only way to be sure. ;D

Modded, Speedballed Crack + Sennheiser HD6XX
STAX SRM-353X + SR-L500
STAX SRM-313 + SR-L300
-Jørgen E. J.


Offline BZ58

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Reply #1728 on: March 28, 2018, 10:58:54 AM
Caveat emptor /ˌkævɛɑːt ˈɛmptɔːr/ is Latin for "Let the buyer beware"

Looked it up. Today I learned.



Offline InnerTube

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Reply #1729 on: March 28, 2018, 12:01:55 PM
Could anyone help me with a determination if the 6C5G can be used as a direct replacement for the 6080 in the Crack.  Thanks in advance, JS

Innertube (John Spain)
[email protected]


Offline Doc B.

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Reply #1730 on: March 28, 2018, 12:12:44 PM
Not even close.

Dan "Doc B." Schmalle
President For Life
Bottlehead Corp.


Offline InnerTube

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Reply #1731 on: March 28, 2018, 12:18:13 PM
Thanks for the quick answer.  It is great to have this resource.

Innertube (John Spain)
[email protected]


Offline Paul Birkeland

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Reply #1732 on: March 28, 2018, 12:49:23 PM
Could anyone help me with a determination if the 6C5G can be used as a direct replacement for the 6080 in the Crack.  Thanks in advance, JS

A pair of them would probably work in place of the 12AU7, but it would take a really unusual adapter or a much larger chassis plate.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline rabele

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Reply #1733 on: March 29, 2018, 05:45:12 AM
Loving my Crack! Aptly named too as you've definitely gotten me hooked on the sound and the hobby.  Speedball ordered.  Using HD600s and an Apogee Groove DAC.

Regarding rolling, would it be appropriate to add "M8136" and "VX8136C" to the list of 12au7-equivalent tube types?  I believe these are additional British designations (if not identical to?) "CV4003".  Stumbled across these while researching the codes of a Mullard I bought (full code is 631 R4I3, FWIW).

My kit came with a nice RCA 12au7 and I've also tried a modern Electro-Harmonix (which sounds better than I was expecting for the price and provenance).   Can't say I loved the winged C/SED/Svetlana 6H13C I got as a backup for the JAN Philips 6080WC that came with my kit.  It sounds loose or rough to me, YMMV.

Thanks again for the kit and the community,
rabele

Crack w/ Senn HD600


Offline adeep42

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Reply #1734 on: March 29, 2018, 06:40:24 AM
Have really enjoyed my Crack+Speedball for some time mostly with Tung-Sol 6520 and NOS Mullard 12AU7. After reading so many posts about 6SN7s and adapters, I couldn't help myself. Got the Garage adaptor and picked up a 1951 National Union Blackglass from Brent Jesse. Really enjoying the combo. With my HD650s audio seems "rounded" and musical with plenty of detail and definition. The adaptor seems well made and certainly doesn't distract from the appearance of the Crack.
« Last Edit: March 29, 2018, 06:42:34 AM by adeep42 »



Offline dasman66

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Reply #1735 on: March 29, 2018, 05:39:10 PM
Let it run overnight and see if that resolves the issue.  Arcing can sometimes be gas in the tube, and getting it nice and hot for a long period of time can resolve the issue.

Just dropping a note... I let it play music for about 8 hrs a few days ago and the problem seems solved.  Hasn't arc'd at all since then.   I have it paired with either a Mullard CV4003 or CBS 5814A (until I figure out which I like better).

Thanks for the suggestion!



Offline BZ58

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Reply #1736 on: April 13, 2018, 09:00:55 PM
I recently received this tube in the mail. It’s a Chatham 5998, and "650" with the letter J is printed on the base. It has a clear top. The description stated that it has "triple mica, black plates and twin bottom D getters.”

Are bottom or top getters better? Or does it make a difference? It sounds great. Just curious about some details. Also would like to know what year this tube was made in.

There’s so many variations of the Tung Sol and Chatham versions of this tube. I’ve searched through this and other threads to learn about these tubes. I’ve read the 116 pages in this thread.
« Last Edit: April 13, 2018, 10:02:38 PM by BZ58 »



Offline InnerTube

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Reply #1737 on: April 14, 2018, 02:06:51 AM
A pair of them would probably work in place of the 12AU7, but it would take a really unusual adapter or a much larger chassis plate.

Thanks very much for your helpful reply, JS

Innertube (John Spain)
[email protected]


Offline Paul Birkeland

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Reply #1738 on: April 14, 2018, 05:34:58 AM

Are bottom or top getters better? Or does it make a difference?
The getter is just a little piece of metal that holds the barium as the tube is assembled. The barium is drawn off the getter and onto the glass near the end of the manufacturing process, and after that the metal shape referred to as the getter serves no purpose!

The getter shape and position is brought up mostly as an identifying mark.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline attmci

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Reply #1739 on: April 14, 2018, 01:37:54 PM
I recently received this tube in the mail. It’s a Chatham 5998, and "650" with the letter J is printed on the base. It has a clear top. The description stated that it has "triple mica, black plates and twin bottom D getters.”

Are bottom or top getters better? Or does it make a difference? It sounds great. Just curious about some details. Also would like to know what year this tube was made in.

There’s so many variations of the Tung Sol and Chatham versions of this tube. I’ve searched through this and other threads to learn about these tubes. I’ve read the 116 pages in this thread.

Nice clear top bottom getter 5998 close to WE421.

50th week of 1956. I could be wrong.
« Last Edit: April 14, 2018, 01:57:02 PM by attmci »