Need tube 101 info

Ok I'm new to this tube preamp world and I'd like to know a few things. I've acquired a BAT Vk-3ix that needs new tubes but I'm not sure I understand what tubes do what and how to properly "roll" them. I don't want "bright" tubes but I'm completely at a loss as to which brands I should be looking at.

Also what do the two tall inboard tubes do, and what do the small pairs to the left and right do?

When you get a matched pair of the small tubes does one go on the left and one go on the right?

Can you mix brands on the left and right. For example can you have brand x and y on the left and x and y on the right? Will that hurt anything? Or should all be the same brand?

I know these may be simple questions but I gotta start somewhere I suppose.
Ouch. I suggest you find a local dealer and have him explain to you.
Hmmmmm. Didn't realize the question was beyond the capabilities of the written word of a group of enthusiasts. I get the generals, but the way some tube-o-philes go on about the things you begin to wonder if there is more art than science behind it. I'm just trying to get users experience - not dealers at this point.
Btw I have no audio stores where I live - nowheres near, unless you count Best Buy. Somehow I don't think they will understand.
I have been following your story about this new BAT preamp in your other threads, as well, with interest. Here's what I know for sure. BAT preamps, tube or solid state, don't make noise. I have nothing to do with the company and don't currently own any BAT equipment but I know your problem is not normal. I know people that have used BAT amps and preamps with ultra efficient speakers, like horn designs, and they are dead quiet even under the most demanding applications.

In my opinion, this is the safest and easiest way to get to the bottom of what your problem is. 1. Call BAT. I'm pretty sure that you have some tube issues. Given your explanations in the other threads, I'm not 100% convinced, though. I would explain the problem to BAT and see what they say. You have nothing to lose and BAT is very concerned about quality issues. 2. If you do need tubes, try to go about it with 0 risk. I recommend The Cable Company. Yes, they are known for cables, but they sell a huge amount of tubes, as well. They are also known for their lending program. They lend me all kinds of stuff other than cables to try before I make a purchase. I am fairly certain that they will lend tubes as well, but you will need to ask them. 3. I know in the other thread, I said you made a good purchase. I stand by it. You probably just need a new set of tubes. Don't make a nightmare out of this for yourself. Get the preamp working, listen to some music and don't 2nd guess every little thing. You'll see what I mean once you get the preamp working.
Fear not as you can have a lot of fun as a newbie "tube roller". Try to avoid the "local dealer explanation" option as the "audio salon" salespeople often (not always...there are some nice people out there) are opinionated, desperate burn outs with more attitude than a fashion week shoe designer, the attention span of a hamster, and will make it clear that they don't like you unless you plan to drop 9 grand on cables. Mixing tube brands on the left and right can give each channel its own sound, but you shouldn't want that. Perusing your options at is what I suggest...there are great inexpensive options for the tubes you require, and if you call them somebody there will talk to you like you matter. They turned me on to a LESS EXPENSIVE (!) 12ax7 driver tube brand because they thought it would sound like what I seemed to want...they were 100% correct, and have a return policy in case they're not. Also, avoid the churlish and self satisfied opinions of the A'gon "tube snob mafia" or you'll wind up with 2 grand worth of dusty Bugle Boys salvaged from a 1952 Lithuanian helicopter.
As your current tubes are not up to snuff purchase a complete retube kit for $90 online (thetubestore) in order that you will have a basis for comparison once you start experimenting with more exotic tubes.
Thank you for your time and information. I have been to and I did a lot of reading and ordered the OEM package of Electro-harmonix - evidently the Sovtek's are not made anymore. This set will be my "base" from which to compare others with. I am also looking for a matched pair of Mullards to replace the bad one currently in the pre amp.

As for the left/right issue, I didn't mean one brand on the left and one brand on the right, I meant one of each on the left and one of each on the right.

Sorry if that was confusing.
Hi Last Lemming.

I would also recommend familiarizing your self with which tubes do what. In a tube amp, certain parts of the tube layout will alter the sound of the amp more than others.

That is one of my questions in my original post. I would like to know what and why on my specific piece.
Last_lemming...with regards to your last question, I would recommend calling BAT's customer service/technical support folks to walk you through what the difeerent tubes do and if they have recommendations on which sets impact the sound more than others. Also ask them if they have recommendations for certain NOS tubes in each of the slots. You will likely get an explanation of the first question for sure (what the tubes in different slots do and which to tube roll first for bigger impact on sound) and less likely to get specific recommendations on what NOS tubes to try out (although you never know).

The other respected source you will find often talked about on Agon when it comes to tube rolling (although somewhat controversial) is Upscale Audio. They carry BAT and the owner will have strong opinions about what tubes to roll. He sells NOS and current production tubes and he may be another good source to talk to. Good luck.
Get a hold of Jim Mcshane and ask about the current New Sensor Gold Lion series of 6922, and 6V6 tubes, which I believe your preamp uses.
Thanks for everybody's help. I will call BAT tomorrow. The preamp looks well looked after. No scratches and no dust on the inside. I know that doesn't tell the whole story, but it's a nice thing to know. The crackling sound is faint and did switch sides when I switched tubes, so I'm fairly confident it's tubes, but when I talk to BAT I'll see what they say. As for sound quality it is quite a nice match and sounds great on the Thiels. There is something palatable about the music now, and I think I made a good choice. If it should be a bad cap or not tube related, well off to BAT it will go, and my really good deal just becomes fair deal.
Last, try this site for basic tube info: I know I've seen another site that had good audio-related tube info but I can't seem to find it right now. Maybe others will recommend a site. I'm not sure a conversation with BAT will be helpful re: NOS tubes. My understanding is that they don't recommend using NOS tubes. However, I had an email conversation with Viktor when I first bought my VK-3i and he was very gracious. - Dick
Thanks Djohnson,

I just got off the phone with BAT. Not sure who I talked to but he sounded Russian - I think. Very nice guy. He thinks is a tube problem and that I should try that first and if my problem persists then I can call back and we go from there.
Good deal. Yes, the guys who run BAT are Russian. Don't let this experience put you off of tubes. The rewards are often great and tube preamps aren't really all that much trouble. I'm sure yours won't be either, once you get it running properly.

Like you, I am new to tubes. This was a great help
Good news so far! Got the EH tubes in, I flicked on the unit - quit and no ringing or crackling. Also yhe hiss that is there requires my ears up to the speaker to hear and is thesame level on both speakers. But my wife is watching tv so I'll have to wait an hour or so for any listening. Wives! There so silly with their 2d image moving picture shows! Right now I'm just letting everything warm up.
You had better be careful or the level of hiss in the house will go up dramatically and the tubes won't be the only thing that is ringing!
Wise words my friend, wise words.