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Preamp 6922 tube help

So my favorite tubes out of all the ones I've tried are early 1960 Siemens CCA, i find them to have an exteremely clean sound, fuller flat, tight bass, great imaging, just everything you would want. But because my system is on the neutral, the CCA has tipped it to the brighter side because of the "sparkle". I was wondering if anyone had another recommendation for tubes that perform like the Siemens, with its sense of realism but without the brightness in my system. 

Here are the tubes I've tried 


Telefunken E88CC ULM - clean tubes but the bass is too rounded out.
Mullard E188CC - too warm, way too warm
Voskhod Singlewire - great tubes but just didn't feel like didn't have any characteristics
Reflektor Single Wire - seems like the mids were a bit warm, but very nice tubes, but i would always rotate them out after a period because they didn't feel too accurate, but very sweet. 
Amperex - Forgot which ones but the highs and lows were rolled off. 
Electro Harmonix 6922 - has a basic tube sound to them on the warm side of things. 






thewatcher101
jea48
4,486 posts
 
tomcy6,

Thank you.
You are correct. I guess I just didn’t check out the pictures close enough. Taking another look sure enough I clearly can see the shiny metal plate and the aluminum tag with the stamped date codes. In my rush I guess I was trying to point out the differences in the two halo getter supports. The eBay seller says grey plate in his ad. Though he doesn’t say all gray plate. I knew better, I should have taken a better closer look at the pictures.

How about the boxes shown in the ad? I though the blue / yellow boxes were for the older all gray plate Siemens tubes. Later dates were the orange / blue boxes weren’t they?

http://www.ebay.com/itm/2-Siemens-CCa-6922-6DJ8-Vacuum-Tubes-NOS-NIB-Amplitrex-Tested-Matched-Gold-P...

For what it’s worth my first purchase of a pair of Siemens CCa tubes I bought here on Agon around 2004-2005. I was green and did not know what to look for. I thought I was buying the real deal but instead bought a pair with the rod halo getter support. And of course they had the same things you pointed out in your post.

Thanks again,
Jim

tomcy6's avatar
tomcy6
2,597 posts
 
thewatcher,  I think you're going to have to talk about your system and the sound you want with the various tube sellers recommended and buy from the one who convinces you he's got what you need.  Tubes will sound different in different gear and I don't think we can accurately predict what will work for you.
bbroussard
189 posts
 
Not sure which Amperex you tried, but I found the early 60's 6922/7308 to be the best in my system.  Far superior to the later ones.
tomcy6's avatar
tomcy6
2,597 posts
 
Jim, You're right about the boxes.   I think the seller is trying to fool somebody with the boxes and the way he took the picture. You can see they’re shiny shields but only if you look at them closely. For the price he’s asking, those should definitely be NOS grey shields. He should point out that they are not. But he’s got 100% positive feedback. You gotta watch out on ebay!
terry9
2,353 posts
 
I tried quite a few 6922 variants. By FAR the best was early '60's Telefunken  specially selected for Hewlett Packard  for use in their aerospace test equipment.

The boxes bear the HP logo on their seals.

I think that these were the last tubes that HP trusted anyone to supply with factor seals. After this, they hired summer students to test cartons of tubes, and kept only 2 or 3 out of 100. The rest went in the dumpster. New Amperex 6922's. In the dumpster. So went the stories in the engineering schools in LA at the time. Which would explain why HP branded tubes cost the EARTH.

Good luck finding any. The last NOS sleeve I saw for sale was nearly 20 years ago, and I bought it too dearly.
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