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September 30, 2020, 06:37:06 PM

Author Topic: Tube rolling in the Mainline  (Read 5700 times)

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Offline Tom-s

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Re: Tube rolling in the Mainline
« Reply #15 on: September 24, 2018, 01:39:19 AM »
Getting this thread up!
Anyone tried other regulator tubes in the Mainline?

Did it make a difference?

Anyone tried E80CC / 12BH7's?

Offline carlsor

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Re: Tube rolling in the Mainline
« Reply #16 on: October 04, 2018, 07:22:06 AM »
I would like to purchase a second pair of 6C45P-E tubes which have limited availability.

Sovtek tubes are the most widely available for as little as $28ea.
OTK tubes in kit sound great. Similar looking tubes on ebay from Russia or Ukraine available for a little as $10.90.

Any advise?

Online Paul Birkeland

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Re: Tube rolling in the Mainline
« Reply #17 on: October 04, 2018, 09:29:45 AM »
Get the ones on eBay from the general area in the world where they were originally made.

-PB
Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man

Offline Tom-s

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Re: Tube rolling in the Mainline
« Reply #18 on: October 18, 2018, 06:54:55 AM »
Can i safely ask the Mainline heater supply to provide 0.3A extra current for E80CC?

Online Paul Birkeland

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Re: Tube rolling in the Mainline
« Reply #19 on: October 18, 2018, 07:06:01 AM »
Yes, but no more!
Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man

Offline carlsor

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Re: Tube rolling in the Mainline
« Reply #20 on: October 28, 2018, 03:21:37 PM »
I own B&K 707 and Jackson 648 tube testers.
The 6C45P-E is not on any chart for testing on these units.

Does anyone know how I can test these tubes?

Thanks.....Ross

Offline Doc B.

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Re: Tube rolling in the Mainline
« Reply #21 on: October 28, 2018, 03:25:52 PM »
Plug them into the amp and if they bias up and sound good, they are good.
Dan "Doc B." Schmalle
President For Life
Bottlehead Corp.

Offline adydula

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Re: Tube rolling in the Mainline
« Reply #22 on: October 29, 2018, 03:46:49 AM »
Ha! OMG....now we have discovered besides using the Mainline as a great headhone amp it can also be used as a 6C45 tube tester!!!

 :)

Alex

Offline Tom-s

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Re: Tube rolling in the Mainline
« Reply #23 on: July 05, 2020, 09:50:43 PM »
I've always wanted to try a Western tube equivalent of the 6S45P in my Mainline. There was this one time PB said that the pentode E55L (triode connected) might just sound good in Mainline, someone just needed to try. It would involve some serious surgery though. In the collection there's both US Amperex New York and Mullard Mitcham factory made E55L. But the major work needed for the magnoval socket held me back all this time. It's the most left one on the line-up picture below. On the right you see the dwarfed 6S45P from the Mainline.

Recently another closely related valve, this time from Telefunken, found it's way into my collection (in the middle in picture). This is a triode from the 60's that equals or even surpasses the 6S45P performance named EC 8020. Fortunately the surgery needed for this tube only involves changing the tube pinout at the socket. It's close to plug and play! Be sure to add grid stoppers ( appropriate value) to each connecting pin as high transconductance tubes like this tend to oscillate.

How does it sound? Well, it's the known Mainline sound to me. No angels singing in my ears or anything. And Mainline sounds great! It's the best sounding amp I own from the technical point of view and now comes with "the queen of triodes".
« Last Edit: July 05, 2020, 09:53:33 PM by Tom-s »

Offline mcandmar

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Re: Tube rolling in the Mainline
« Reply #24 on: July 05, 2020, 11:26:42 PM »
Pretty little tube too.  I tried to track down a pair of these to try and found they really are made of unobtainium.
M.McCandless

Offline Doc B.

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Re: Tube rolling in the Mainline
« Reply #25 on: July 06, 2020, 05:21:23 AM »
PB converted a 6C45pi amp I built many years ago to run WE437As for a very good friend and customer. He was happy with the result and considered it an improvement. I thought the 437A sounded very nice but found that I very slightly preferred the 6C45pi. To me the difference was more of a flavoring thing than a measurable improvement in performance.
Dan "Doc B." Schmalle
President For Life
Bottlehead Corp.

Offline grufti

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Re: Tube rolling in the Mainline
« Reply #26 on: July 06, 2020, 07:39:36 AM »
How on earth did you recently find EC8020's, emphasis on recently?

Offline Tom-s

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Re: Tube rolling in the Mainline
« Reply #27 on: July 07, 2020, 06:33:47 AM »

@DocB: That's exactly my experience with these. It's still just the Mainline, only with a different flavor. They have inspired me to experiment with a E55L as a spud speaker option. I'm now even considering rewiring the S3X "a bit" to get there.


@ Grufti: With some patience, persistence and luck. Like all tubes. For these's i've been searching four years now, ever since i figured i wanted to buy a Mainline at some point in the future.

Offline Love Rhino

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Re: Tube rolling in the Mainline
« Reply #28 on: September 14, 2020, 05:02:57 PM »
Tom-s did you try the e80cc?  Any difference in sound?

Offline Tom-s

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Re: Tube rolling in the Mainline
« Reply #29 on: September 15, 2020, 09:41:55 AM »
I can't say it does much. It might, but then again I tried it years ago. Can't honestly recall any of the influence it had. I would recommend tube rolling ECC82's from your Crack and see for yourself. The PT and/or LT regulator are pushed harder with E80CC.

In the end, went back to my trusted Philips Heerlen ECC82 (selected a very strong testing one for the job). Had this in for the past few years and am always happy to see it flash (even with the tube shield on) and confirm power is on. Now with the tube shields from the 6C45P gone, this flash is no longer "needed" but it's still in the same place.