6922 tube question


I have a preamp which uses two 6922 tubes, currently Sovtek. To my ears, the sound is overly warm and the bottom end sounds bloated. I'm wondering if anyone can suggest a tube, 6922 or otherwise, that will clean up the sound.

I'd like a crisper, more neutral sound while maintaining strong lows (though not bloated) and extended highs. Any thoughts are highly appreciated.

Also, how long is recommended for tube break-in?
one_speed
You got to try out the Telefunken CCa. I tried them on my previous CJ 17LS. They sound more in mid and high, more neutral than Siemens CCa. But I also believe either amp or preamp should be upgraded with oil caps or copper caps, which could help the sound more dynamic and detail.
My preamp came stock with RAM 6DJ8's - you can guess the brand of preamp. I bought and tried some mil-spec Sylvania 6922's, and they were glorious!

Lazarus Short
Just wanted to say hello and thanks for all the replies to my inquiry. So you know, the speakers are spiked. I've played with position a bit, but should do more. I have a feeling, after reading your replies, some of the warmth comes from the oil caps, and some from the positioning of the speakers. I'm also not used to a very warm sound, so this throws me a little.

Thanks much to all, I'll check into these things.
One_speed,

It's real funny that you should mention that the Sovteks are overly warm & that the bass is bloated!!!! Sovtek 6922 are *NOT* known for this character! In fact, as Newbee correctly pointed out, Sovtek 6922 are known for the diametrically opposite character - lack of warmth! I have 6922 in my tube pre - they are *not* warm/lush or overly bloated - they are on the accurate side of neutral.

It seems that you have some OTHER problem in your system! It is *not* the tube! Check your speaker position in your room? Are they too close to the side &/or rear wall? That'll bloat the bass thru room corner reinforcement. As Brauser suggested, have you spiked your speakers?
Find Newsensor Corp, buy Electro Harmonix Platinum matched 6922s and be done with it. They smoke 90% of the NOS tubes I have owned.
If you don't have a lot of money to spend, try www.eurotubes.com's E88cc $8.50@.
There are regular Sovtek 6922's and there are the flat gray plate Sovtek 6922's, which are very much better, but certainly not the best, IMHO.

I would search around for some folks who have your particular preamp and, if you're lucky, at least close to your other components. Even they will only be able to give you general guidelines as the 6dj8, 6922, 7308 tubes are very system and component dependent. Also, the 6n1p is a cheaper option which some have found superior to many of these other tubes in some applications like preamps (check with the mfg., though, because 6n1p's are not necessarily interchangeable in all cases).

Sure, the Siemens and Teles mentioned will be sweet sounding - IF they are the real thing, IF they are the proper vintage, IF they are closely matched, and IF they have been tested closely with respect to microphonics. Dealing with a reputable and honest tube dealer will eliminate some of this anxiety. Might be more costly, but worth it in the long run.

Many other manufacturers have made great tubes in this family - Mullard being but one other not mentioned. The US-made White Label Amperex PQ's can be very good.

All of this said, even the best of the best of the Teles, who some will say are the best for everything, may not be the best in YOUR application. I have had more than a few components based on this tube family and was sometimes surprised at what sounded best. For instance, I had a Kora Eclipse preamp and I tried about a dozen different tubes in it, some being the very expensive varieties of brands listed here. In the end I found that the best for that component, in my system, and to my ear was a trio of La Radio Technique 7308's. Go figure.
For lots of detail with good to great bass go for NOS gold pin Seimens and for good detail with lush mids and great bass go for NOS Telefunkin Falcons! Can't go wrong with either tube, considered some of the best!
Happy Listening!
Before you experiment with tubes try a different (SS) preamp and see how your system sounds. The Sovteks do not in any way sound the way you've described. They are not warm! They're bright and harsh. There's more going on here than tubes.
I basically agree that the problem you speak of is probably
not the fault of the Sovteks. Make no mistake that there
are better tubes out there. If you haven't spiked your
speakers or used some resonance control with your componets
you may find that doing some 'tweeking' may really help.
Of the dozen or so 6DJ8s I have personally experimented with in preamp application, the Siemens 7308s ae my favorites. But, for the price, the Siemens 6922s and Amperex 6922PQs are hard to beat. Joe's Tube Lore at AudioAsylum's FAQ is a good place to go for reviews of tubes of this size.
Unfortunately for you most of the qualities that you seek are those for which the Sovtek is generally condemmed, that it lacks any warmth. Personally I have not heard a 6922 with less warmth than the Sovtek but I'm sure there must be some NOS tubes that do. I use 6h23's - they are nearly identical to the Sovteks but are a bit smoother and almost as quiet. I find little difference in small tube sound after they have run in about 24 hours.
If you're looking for a more revealing tube with good transparency and soundstaging try a pair of NOS Siemens 6922s or CCas. Good luck.