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-   -   Were can i bay a Telefunken 6ak5 ? (http://www.diyaudio.com/forums/tubes-valves/133194-were-can-i-bay-telefunken-6ak5.html)

izzik 15th November 2008 08:35 AM

Were can i bay a Telefunken 6ak5 ?
 
Were can i bay a Telefunken 6ak5 ?
It's for the yaqin cd buffer .
I can't find a plaece thet sell this tube !

pleace help

i am sorry for my poor english

Cobra2 15th November 2008 08:40 AM

I think you will have trouble locating a Telefunken 6AK5...as I believe this is an U.S.-only tube-number.
Try EF95 !

Arne K

izzik 15th November 2008 09:28 AM

I ALLSOW CAN'T FIND THE TELEFUNKEN EF95 !!

Cobra2 15th November 2008 09:48 AM

:smash: http://www.google.com/ :smash:

http://cgi.ebay.de/EF95-6AK5-Telefun...QQcmdZViewItem

Arne K

Yvesm 15th November 2008 12:09 PM

Don't be silly !

6AK5/5654 are so common you can have a box of 20 for 5€ !

Yves.

Tubeshop-24 16th December 2008 05:34 PM

Hello,

yes, you can buy 20 pcs. for 5 Euro , but only russian or china produktion.

If you want buy Telefunken tubes, you pay more.

Thank you , Sven Syre

Tubeshop-24

Tubes4e4 16th December 2008 08:28 PM

Hello Sven aka Tubeshop-24 (sic),

Quote:

Originally posted by Tubeshop-24
yes, you can buy 20 pcs. for 5 Euro , but only russian or china produktion.
If you want buy Telefunken tubes, you pay more.
Thank you , Sven Syre
Tubeshop-24

now please tell me, what is the exact advantage of Telefunken branded ones (or Siemens branded ones, for that matter) available for much more money over f.e Lorenz (Schaub Lorenz / ITT) or GE or Sylvania (ECG Philips) demonstrably produced ones, available for much less money?

Regards,

Tom

Cobra2 16th December 2008 09:32 PM

Easy: The glory of paying for an overpriced tube! :D

Arne K

Tubeshop-24 17th December 2008 12:06 AM

Hi Tom,

obviously there are many other good producers, this is something I do not question.

About the difference in quality between China and Russia productions we do not need to talk and even get in this rough for small quantities of money.

If you take the differences Qualtitativen times want to see, I'm going to demonstrate the difference on a Neuberger RMP400. From Leverkusen to Moers is not so far.

Greeting Sven

Tubes4e4 18th December 2008 09:57 PM

Hi Sven,

almost exactly 2 years ago I got 300 pieces 6AK5W / 5654 directly from a Bundeswehrbeschaffungsamt auction of NATO armory stock for 100 Euro, makes 30 Euro-Cents per piece. NATO supply number 5960-12-300-5560, subcode D/BS02/H2268, batch accepted 0/87 (so, released 20 years after admission into warehouse) from Siemens AG München.

Opening about two dozen of boxes, I found a wild mixture of several different system constructions (but all rebranded as "Siemens"), some of them clearly identifyable by f.e etch codes to be of Philips ECG (Sylvania), RCA and General Electric origin. Even a Raytheon, with the original brand print still visibly due to lazy wiping before rebranding. Eventually I also found some samples that seemed to be of real Siemens production origin.

This wild mixture from - granted - highly regarded manufacturers obviously met NATO standards over the whole lot (likely several thousand tubes) to be accepted, so it is safe to assume that one can get NATO/MIL-accepted quality EF95/E95F/EF905/6AK5/6AK5W/5654/5654W for much less than an Euro if one knows where and when to look for them.

Looking close at the EF95 NATO/MIL variant specsheets for acceptance range of tube coefficients and related data, especially transconductance and anode current, you probably will fall from chair, noticing an acceptable range covering a factorized range of 2 (gm) up to 4 (Ig2) for NEW tubes within a batch. To deal with such extreme (but mind you, NATO spec´d) tolerances, any circuit using them must be _designed_ to be very tolerant as well.

In other words, and to come back to tube audio, a circuit that gives different sonic results with EF95 MIL spec types according and withing those specs, just is nothing else but an example of bad engineering.

I wholeheartily admit that it is not easy to design an audio circuit that will work satisfactorily with "any EF95 within allowed and layed down specs". But for those that can do such a design, just any 0,30 € EF95 will do, indeed. Yves, to whom you answered, certainly can do such a design, I can asure you.

Thank you for offering me to show me your point using some certainly very expensive tube tester, but as you might know (or not), I don´t depend on tube testers for my opinion, but I prefer to do real tracings, like for example this one. (This plot actually is derived from averaged data of 4 sample tubes taken (by chance) from the 300 pcs lot I mentioned above).

Regards,

Tom Schlangen


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