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Upscale audio advice

I have been looking to change the tubes on my BAT VK-30 from the Russian made 6922/6h23 which work fine but am looking into upgrading them. I looked at the Upscale selection and a few options initially caught my eye. These are as follows:
1)Amperex 7308 vintage gold pin
2)Amperex 6DJ8/ECC88 Bugle Boy
3)Ediswan CV2492/6922
4)Mullard 2493/6922 & Mullard E188CC/7308

All of which, if I choose their Platinum grade, range from $70 to $110.00 each which seemed pretty reasonable to me. The problem is, their sales guys tells me that none of these are suitable for my Pre-amp. He goes on to tell me that the only units that will work are the very same 6H23's that I already have. Is this sound advice from them given the fact that I would like to spend some decent coin to upgrade or do they not wish to deal with me? I have seen in other forums that they tend to want to sell to customers who have purchased equipment from them. Is this true? I do want to change my tubes given the fact that they are about 5 yrs old and definately are due for a change. I find it hard to believe that the only option they have that will work with my VK-30 would be these cheaper $35.00 per tube units. Any further comments anybody may want to add to this or advice you may have for me?
vinylmad814
djohnson54
396 posts
 
Vinyl, I got 4 Phillips platinum grade PCC88/7DJ8s (which are a direct replacement for 6922s) for $35 each and 2 Pope 6V6GTs at $49 each. The Pope 6V6GTs were at the suggestion of Kevin rather than the ones I had picked out (can't remember which ones now). The Phillips PCC88/7DJ8s were the ones he had to check his notes on. He thought he remembered a customer complaining they became noisy in their VK-3i but he still believed they would work. I can confirm that they work wonderfully in my preamp and they are NOT noisy. They also are not the high-dollar tubes you were apparently looking at. :) I'm very pleased for not much money ($238 plus shipping)! Dick
mechans
3,048 posts
 
Your problem is simple- either your preamp uses a tube that is a direct equivalent of a 6922 or it is the other type which can only be replaced with the same tube. If you have a 6922 whatever it is called in Russian you have the options to roll a whole variety of tubes into it. The family of those tubes includes 6DJ8,6922,7308 and Cca.

I am certain however that only one of the two mentioned and no I don't know which, is only compatible with itself.
Get that straight and then post for suggestions. I happen to use amps that use 6922s and rolled in number 4 on your list CV 2493s which are Mullard military tubes also called E88CC-01s, Unfortunately it is the nomenclature of all the 6922 variants has you confused.
Just figure for certain that the pre is compatible with 6922s and take it from there.
I would also call Victor back because I think he misunderstood your basic premise when you gave him Upscales suggested options, just ask him if you can use a plain old 6922 in your pre. IOW I think your inforest and can't see the trees. I will actually post a question on tube asylum asking if a 6H23 is a direct sub for a 6922 or not.
mechans
3,048 posts
 
I looked it up. If you Pre uses 6H23 then any of the 6922 family of tubes can be directly substituted. It has been my experience that using one of th NOS/OS choices that Upscale has on offer will sound better than the Sovtek. Others may disagree but you should explain as best you can what sonic charactristics you prefer. If your not quite sure which appears the case I have found that Amperex white label tubes are well liked.
The gold pins are usually present on the 6922 and up. The 7308 has slightly different electronic parameters making it a particularly reliable tube as well as yielding better sound in most cases. Given all that the best choice in the absence of any specific direction would be the 7308 Amperex as long as they are not the cheesy JAN green letter ones. Otherwise if you have the money to play around buy a few different types and audition them. Tubes are resellable if you don't want to start collecting but be careful its a slippery slope when you first hear the magic of a newly tried tube. It can be habit forming.
samhar
1,048 posts
 
I was of the impression that you can use a 6922 in a 6DJ8 circuit but not a 6DJ8 in a 6922 circuit and that PC88/7DJ8 wasn't compatible in either of the circuits!!!??? Best to check tube data sheets!!!!!
samhar
1,048 posts
 
... I also think nos Amperex, Telefunkun, Seimens and Mullards sound better than any Russian 6922/6DJ8 in every circuit I've heard them in. They all have a different "house" sound that you'll have to try to hear what you prefer in your preamp just make sure they are graded for pre/phono as Rodman99999 mentioned.
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