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Banned on 1/22/2011 for repeated rule violations after multiple warnings. Registered Member #3299
Joined: Sat Oct 09 2010, 08:11PM
Location: Bantown, USA
Posts: 220
I can do a trade with anyone, i have a 25 amp isolation transformer, i have 2 variacs, or i could just by one, I'M NOT BUYING REMAKES FROM CHINA AGAIN! i would like 2 tubes but i can settle for one.
Well, they usualy have thinner plates and are of lesser quality, worse heater, etc. Also, they have rather loose specs, while RCAs are almost the same, tube to tube.
You see, back in the old days, tubes diddn't need maching, because new tubes were basicly the same. When Japan started making tubes on the 70s, for 1/2 of the price, companys started to use the matching ldea. The japan tube had loose specs and needed matching
Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
803 wrote ...
Well, they usualy have thinner plates and are of lesser quality, worse heater, etc. Also, they have rather loose specs, while RCAs are almost the same, tube to tube.
You see, back in the old days, tubes diddn't need maching, because new tubes were basicly the same. When Japan started making tubes on the 70s, for 1/2 of the price, companys started to use the matching ldea. The japan tube had loose specs and needed matching
Where do you get all this sort of thing? Is it some kind of folklore?
Registered Member #1334
Joined: Tue Feb 19 2008, 04:37PM
Location: Nr. London, UK
Posts: 615
803 wrote ...
Well, they usualy have thinner plates and are of lesser quality, worse heater, etc. Also, they have rather loose specs, while RCAs are almost the same, tube to tube.
You see, back in the old days, tubes diddn't need maching, because new tubes were basicly the same. When Japan started making tubes on the 70s, for 1/2 of the price, companys started to use the matching ldea. The japan tube had loose specs and needed matching
Do you have any documented, as opposed to apocryphal, evidence for these statements?
I have a whole bunch of antique RCA tubes and Bendix (Red Bank) and IMHO, they differ considerably from tube to tube within manufacturer - a good gm tester is essential, even when matching channels in an SE amp.
Wander over to the tubes forum on diyaudio where literally 100s of engineers (not "audiophools") building & researching tube amps hang out, and see if they agree with you
Registered Member #1334
Joined: Tue Feb 19 2008, 04:37PM
Location: Nr. London, UK
Posts: 615
Steve McConner wrote ...
Yeah, sorry, that is complete BS. Tubes needed matching back then too. At least, my collection of Mullard EL34s and GEC KT88s did.
Nicko, Red Bank tubes have almost mythical status. Which ones have you got?
5 matched pairs each of JAN 6889s and JAN 6384s.
Waiting...
...for the right project(s)
and
...time to do the above...
Next project will probably be be SE based on 6C33C-B - already got the iron (actually, already had it for about 2 years ) I've also got a load of 13E1s with their (very large iron) waiting likewise...
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looking for origanal rca 811a tubes
) I've also got a load of 13E1s with their (very large iron) waiting likewise...
