|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
99.234.172.233
In Reply to: RE: Hiss posted by Vinyl Valet on February 03, 2015 at 04:37:34
If you want great sound AND quiet, try a Telefunken E88CC. Not cheap, but neither are GLs that last 3 months. Still widely available NOS from places like thetubestore or Upscale audio.
Follow Ups:
Thank you. Yes, I'm familiar with the NOS Telefunkens. You're right, had I known about the high failure rate of the Gold Lions, the NOS Telefunkens would have looked much more attractive.
I was mistaken in my original count. I actually have five failures out of twelve for hiss and most occurred before the 200 hour point.
Do you or anyone else have any knowledge/experience with these new production Telefunkens? Same price as the Gold Lions.
Well, I sell the 6922 Genalex and I don't know about any such "high failure rate". I reject a few (well under 1%) in testing/screening, but the number I get back from customers is miniscule! And I've sold 1000s of them. I know that some have gone into Herron gear, I'm not sure about the other unit you tried them in.
Have you cleaned the sockets thoroughly? That might be worth the effort regardless of what tubes you end up with.
In any case all I'm saying here is that based on my experience the failure rate on the Genalex is VERY low, and the tubes are quite reliable. They may or may not be the tube for you, but they are quite good quality.
To prevent any appearance of conflict of interest, if you want to purchase new 6922 stock I will be glad to recommend a high quality vendor other than me.
Yes, I have heard this from a dealer. That's why I'm asking the question here as my experience is consistent, repeatable and always just one of the two triodes.
Yes, I know about and appreciate the importance of cleaning both the tube pins and sockets. Every time I have a tube problem, I remove the tube, clean both the socket and tube pins, even though I did when I installed the tube originally, in this case not so many hours ago. Then I reinsert the suspect tube and listen. Not once during this procedure did the problem go away. Also, if the bad tube is in the Herron, I try the tube in the Cole (and the other way around) and the problem follows over to the other component, always the same bad triode. I've had this failure in both components, so it isn't like either is destroying tubes like an Audible Illusions 3A.
Prior to these Gold Lions, I had used other tubes, both NOS (reasonably priced) and new production without ever having this issue. I've been using both these components for over ten years.
Sonically, IMHO, these Gold Lions are the best current value in 6922s. My two components have never sounded better. I really want these tubes to work for me but after loosing five out of twelve in less than 400 hours, I'm here looking for a reason or a solution.
Based on your feedback, I am going to re-test all five bad tubes one more time to make sure I haven't overlooked something. I will report back in a day or two.
Thanks for your input.
To keep it simple, I just inserted each bad tube (four, the latest fifth failure is still in the Herron until I find a replacement) at V1 in the Cole phono stage. The Cole uses two, very high quality Teflon tube sockets which helps eliminate the dirty/bad socket theory.
Kind of reminds me when we lived on the ocean in Costa Rica. That pleasant kind of white noise, appropriate for surfers but not for vinyl lovers. The faulty tube hiss ranged from bad to extremely bad; all four tubes.
BTW, each of the five bad tubes came from a different socket, four from the Herron and one from the Cole.
If you can try some try some of your old tubes of another brand for a few weeks to see if it still happens,that will tell you if you have an issue with your unit..This is an not an uncommon issue with pass regulators where they can fail and let the B+ rail voltage go to the tubes.If you have a meter,just measure the DC voltage at pin 1 and pin 6 of each tube..If its's way over 100vdc,you need to look at the regulators because It's highly unlikely that many tube failures.
"If it measures good and sounds bad, it is bad; if it measures bad and sounds good, you have measured the wrong thing."
- Daniel R. von Recklinghausen
I would still recommend you clean the sockets. No matter what the socket is made out of - Teflon or recycled Yugo dashboards - contact surfaces still can get contaminated, and the cleaner they are the better. Plus the pin diameters vary slightly on many tubes and it's best to do all you can to ensure good contact. Pin to socket contact is the number one cause of noise in new or nearly new tubes.
And one more thing - the act of removing and replacing tubes in a socket can often clean up the contacts enough so the new tube plays fine. It MAY just be coincidence though, not a problem with the original tubes.
Good luck!
I described my cleaning and testing procedure in great detail. Maybe you're just trying to stress your point. You do it often and with good reason. Believe me, many folks, including myself, very much appreciate your generous sharing of information on this forum.
Okay, I just finished the same experiment on V2 of the Cole. Same results, just not as loud (one less gain stage). And three of these four failures came from the Herron, each from a different position. So I would say that it would be quite a coincidence that the same pin(s) in five different tube positions from two different components are all still dirty or whatever after I cleaned them.
There is absolutely no doubt, after this discussion, that five of the twelve new Genalex 6922 tubes have failed in less than 400 hours. The fact that you have sold 1000s without any returns for this issue is somewhat confounding. Perhaps it's because this type of failure occurs over time, well after any reasonable return period. None of the bad tubes failed in less than 100 hours, which, with my listening habits, would be a couple of months at the earliest.
All this talk and still no clue as to what's going on. My conclusion, based on my experience, is that these tubes are not very reliable. Sad, because they sound great. Prior to these I used new production EH 6922 tubes in the Herron. Never had this type of failure. Very reliable but not nearly as good sounding as the Genalex in this application.
I did, but I wasn't sure how recently the cleaning had been done.
I have no explanation for what you are seeing. I have had a large number of repeat purchasers of those tubes, and I have no record or recollection of any similar occurrences.
I'm sorry I wasn't much help for you.
I have no experience with these new "Telefunkens" (sick). Made in China or Russia no doubt. Not by the craftsmen who worked in the German Telefunken plant in the 1960s. What makes you think they would be any better than the GLs?
Post a Followup:
FAQ |
Post a Message! |
Forgot Password? |
|
||||||||||||||
|
This post is made possible by the generous support of people like you and our sponsors: