That's ashame -- hope you or the fine folks at cj gets to the bottom of the issue -- they are great components.

Best in your troubleshooting/resolution.:thumbsup:

Bob

Joe, you never had your cj components in your system long enough to have anything go wrong :D:D:D

Good move... :banana:

I was waiting for that :yes:

:thumbsup:

I had the same problem. CJ mentioned that there was a bad stash of tubes from EH that were turning noisy. They can identify them by the dates. Once I replaced the EH tubes with the Matsushita 7DJ8 I had it working for over a 1000 hours with no problem whatsoever. A friend of mine received a replacement EH6922 from CJ and also worked with it for over 500 hours without a problem.

I am sure they will. Lew and the cj team are amongst the nicest in the business.

+1 :yes:

Let's hope it is a specific 'bad' tube batch as ronenash mentions. Now, that would be nice & sweet (for an easy resolution).:thumbsup:

Best

Bob

The nicest I have ever met that's for sure. This is one of the reasons for over 20 years now I keep coming back.

Thought I would provide a bit more information on this one.

I am guessing the noise you are hearing in this case is just white noise with no crackling or breakage noises. The white noise will get stronger as the tube ages until the tube becomes useless. If the noise you are hearing does not match this description then you are looking at a different problem.

Tube noise that matches the above is in most cases a result of disintegration of the coating on the tube filament (the heater wire inside the tube). I believe the scientific explanation for this is that once the coating goes bad stray electrons from the filament are interfering with the normal operation of the tube and causing noise.
This problem with the filament coating can be a result operating the tube at higher filament voltages then the 6.3v the tube is designed for or a defect in the manufacturing of the tube.
I have checked the voltages inside CJ preamps and they are spot on so that leaves us with the manufacturing defect as Lew Johnson mentioned. I think Reflector had this problem for quite a while since I have seen it on Gold Lion tubes as well (GL's are premium EH tubes manufactured at the same factory).
The problem is more noticeable when the tube is used in high gain application such as that in a CJ preamp where no feedback is used which reduces the gain. Using these tube in as driver tubes in a power amp will not be a problem in most cases as the tube is configured to driver the output tubes and not to amplify the signal.

This is a rather technical explanation. I hope I have not gone overboard :)
Anyway, I hope this helps understand what we are experiencing.

:applause:

Good clear, concise explanation -- let's hope TT has a bad set of EH's.

Best

Bob

Yes Ron. white noise. that is why it dissappears( for a while) when you change to new tubes.

4 sets of cj EH 6922 in less than 11 months of ownership.

As mentioned previously most of my spare ones are 07 09 dates. Replacement gat two are 09 09 .

BTW, how do you check the voltages inside CJ preamps?

cheers

Hello turntable,

Are your Tubes 6922 in Pair Matching? In my LS16MKII have the JAN Sylvania 6922 in Matching and are very well:D
I have the Sovtec s in Premier 8A and are hard for me in the Sound as well as Electro harmonix
Try the Times with JAN PHiLLIPS 6922 in Matching-Pair and Low Microphonics...
Greets Sounding chris

With a voltmeter on the tube pins when the cover is off. I would not try it if you are not sure what you are doing. You can easily harm the amp by shorting something inside the box.

the 6922 always seemed to lose its high water mark performance in relatively few hours when i used them in audible illusions 3 preamp, cj ls 16 preamp or as input or driver tubes in my music reference amps. the 6h30p tubes in my act 2.2 are much more consistant-amazingly so in comparison. i am now biased against buying 6922 based gear

Ron,

Some folks seem to prefer the Gold Lions. My EH 6922s are fine at the moment... quiet and sound good. The last time I started tube rolling I regretted it but... if they are the best of the EH's do you prefer the GLs?

Thanks,
Bob

Bob,
I found the GL to be a bit better than the EH but their biggest advantage is more consistent quality. The best 6922 tube I have used to date is the Matsushita 7DJ8. I found them to be better than the EH in everyway and Upscale has them for a reasonable price.

One day I'm going to find that pair of Tele ECC188/7308s and put them in the GAT. One day also will get a pair of CCA to try when have some dough.

My ET3SE eats tubes, it seems
 

Thanks for the thread here, guys. I've been wondering if there's been something wrong with my pre as it does go through tubes. Sounds like it is pretty normal.

I've had the pre for about a year and I am now on my 5th tube. The pre is only on when I am listening to it. I'm guessing that I have > 600 hours total on the unit by now. Unit is well ventilated and all that.

It does sound like some amount of tube "rush" is normal, so I may have just assumed that the tube was bad, when it wasn't...just those stray electrons bouncing about in advance of the tube's ultimate demise.

I've tried CJ EH 6922, EH Gold 6922, & GL. I loved, loved the GL's midrange, but it went crackly on me in about a month. The last EH Gold lasted maybe two months before getting noisey.

Oh, the stock 6922s in my ET250S are factory and are dead quiet still after a year or so.

Sigh...tubes are glorious sounding indeed, but kinda high maintenance.

Thanks for the tips about the mfg date.

Well, I just ordered a couple of NOS Tele ECC88s for Mr. GAT. Diamonds, gold pins and all. Found them on sale at Tube Depot last week. Maybe I'll learn what all the fuss is about. They had better be dead quiet.

Wish me luck...
Bob

I've been over there at TDepot a few times now pondering buying a couple of those on-sale Tele ECC88s...I guess it's inevitable. :sigh:

Better hurry. The sale expired yesterday but since I've bought other stuff, they gave me the price today. They seem like good folks to deal with.

Curious as to what is going on as I've had my Premier 17 almost two years without any tubes going bad whatsoever. Also, the Ediswan input 6922s in my LP70S power amp will be three years old in January, still no issues.

haha yea, I hopped over there...the sale had expired. I called them and the person I spoke with said he'd gotten approval earlier today to sell a set at the sale price. I guess we know who that happy customer is. :yes:

So I've got a set on order as well at the good price. I've purchased quite a few tubes over the years from them.

Oh yea, a good outfit for sure. I still enjoy watching their build-your-own-guitar-amp videos now and then,

Glad you were able to get them at the sale price, Bob. You're in for a treat, the Telefunken ECC88s are just plain excellent.

Edit: You too, Ray. Think I had a brain fart there. :o

Thx, Puma Cat. Yea, me too. And a bit worried, I must say. :sigh:

It certainly sounds unusual. I think Rayooo was saying he'd been through a fair no. of tubes on his ET-5 as well. Something with the current ET/GAT topology perhaps?

My CT-5 currently has the Reflektor 6H30 DR "super tube" which is reputedly reknown for going tens of thousands of hours. My understanding is that one of it's primary requirements from the Soviet gov't was extreme durability.

Well I hope the DRs are better than the EBs. I've had three EBs go in my ART amps. I did try the DRs but I really don't think they sounded better than the EBs. In my sytem, the DRs were among other things definitely edgier.

So far the latest ERs seem to be holding up. I'm beginning to think that many of these Russian tubes have real reliability and longetivity issues
:(

Stephen, where did you buy your DR's? I have been thinking about trying them in my BAT VK-52 SE in lieu of the regular 6H30's.

I got mine from a tube dealer that I've dealt with before from Turkey. The prices were reasonable and the tubes came in two or so weeks from Russia. I'm not sure the one's sold by Parts Connexion are real as they look different from any other DR and don't sound that good to me.

I also picked four up on audiogon from someone who had just sold their BAT gear and was also selling their backup tubes.

The DR IMHO might work better in a system that leans to the dark side but definitely wouldn't use them in a lean system.

Dang, Randy, I'll have to go back look, I don't remember off the top of my head.

Randy,
Actually, Myles just reminded me...it was Part Connexion.

All I can say is that mine improved the sound of my CT-5, giving it a slightly warmer tone and a fuller sound than the stock EH's.

Maybe I should try the DR's in my ACT2. Never thought of doing so.

They've certainly gone up a lot in price. I seem to remember buying them from Conus Audio maybe seven years ago for $50 each, now they have them listed for $175. Jeez. :scratch2:

I've had the regular 6H30π-EB version in the Pr. 140 as it breaks in but maybe it's time to try them again. At the time the DR's seemed a little smoother but also a bit more detailed. Previously, it wasn't a night'n'day kind of difference but with the new caps, it might be another story.

Getting back to the GAT/ET5 -- any interest in the CJ crowd with GL Reissue 6922's??? Have some in my stash that I was going to use in a Sonic Frontiers SFCD-1 player & never did.

Best

Bob

Guess not.:scratch2:

Bob

The Conus and Parts Connexion 6H30s are the same. They're not the same color lettering as any other 6H30 I've had.

I did try the 6H30π-DR's yesterday in the PR. 140. I don't know if it's the new Teflon caps or just me talking myself into it, but this time around I noticed a big difference between the two. The -DR's are superior in just about every way: dynamics, clarity, transparency, timbre and frequency extremes.

This is a picture of one the -EB's I was using on the left and the -DR on the right.

http://x55.xanga.com/5c7e01762153228...o225987189.jpg

The -DR looks like what they have at both vendors mentioned. As far as the innards go, the -EB and -DR look the same. In an older post by Victor Khomenko at BAT on the Audio Asylum, he said the -DR's were tubes selected for military applications and had better specifications than the -EB's.

They are awfully expensive.

Joe, your experiences with the DRs parallel mine exactly in my CT-5, interestingly enough. I also noticed a fuller, more natural presentation than the non-DR tubes.

Joe and Ray...

Got the Tele ECC88s today. Listened to some music with the EH6922s in for comparison then plugged in the Teles. One has a very low level, just the smallest bit of hum but do they sound terrific. I have to plant my ear on the speaker to hear the hum but the increased transparency is all over the room at all volume levels. Maybe all this gets better with some break-in time.

Ray... let me know how yours sound. I'm really impressed with the increase in low volume transparency. Still plenty of bottom end. I'm using my PR350 to start as it tends to be a bit more ruthless with detail. Have a meeting tonight so tomorrow will be the trial with the LP140s.


Bob
:music: