Considering A First Time Tube Roll

[Meloski]

The equipment
Amp:Jolida 202, current stock tubes are, pre-12ax7 Tung-Sol, drive-12at7 Electro-Harmonix, power EL34 Electro-Harmonix,

TT: Technics SL1200MKII w/ AT440MLa

MC/MM Phono preamplifier: Lehman Black Cube Statment

Speakers: Martin Logan Motion 40

What I like. (Please keep in mind that I am very much still learning as to what I like).
Bass is good could be smoother.
Mid is strong vocals & guitars sound great.
Highs are very nice, sharp clean very little or no sibilance.

What I don't like.
Overall presentation, it just sounds a little closed in.
I think the amp could be much quieter.

What I want.
I want to open the soundstage, wider and deeper, I would like more separation and clean the whole thing up a little, make me go wow.

Many hours of online research has me looking at NOS Amperex BugleBoy matched pairs tubes for the Pre & drive (I thought that the NOS Telefunken may be just a little over the top, but then again I am only reading about them). Paired with new Gold Lion KT77 quad for the power tubes.

Are there any modern tubs that really perform like NOS? What makes NOS so special?

I may have to retube this amp in stages in what order do you think would be best? Pre, power then drivers?

I am also considering upgrading the TT cartridge to a MC AT33EV.

Please let me thank you for putting up with my newbyness, I am learning as I go here (with much help from all of you). One thing I have learned is that I constantly want more from my system, I assume that i'm not alone here. Just what did I get myself into, I love it.

Always happy to answer any questions you may have. Thank you again for all your help.

Cheers!
__________________

[dougmon]

Based on what you said you're looking for, I think the Gold Lion KT77 may be a good choice. But that's all I would change for now. They may be enough, they may not -- but you won't know unless you listen to them for an extended period. I believe it's best to change only one thing at a time -- then the changes will be more apparent. If you have a little money to play around with, you might also try the "new Mullard" EL-34 tubes.

NOS can be great. Or not. It's kind of a crap shoot. I've had great NOS tubes, bad NOS tubes, and mediocre NOS tubes. Some of the best NOS tubes I've ever had were pulled from old organs and thought to be at the end of their life. Some of the worst were some of the most highly-touted, and they measured extremely well. So be careful and make sure you know what you're getting.

I had tube amps for about twenty years, and I still consider myself a newbie. How tubes sound are pretty dependent on the amp they're in, so while I can make general comments, be aware that I haven't heard your amp.

I hope I've contributed something positive here. I'm always happy to answer questions if I can.

One last thing: when tubes are new, they can sound "closed-in" for a while. If your tubes are new, I would give them a little time.

[Meloski]

How prevalent is the counterfeit NOS tube market?

[AlexM]

Very. Beware, and stick to vendors with a known reputation.

Have a look at this rogue's gallary to get an idea. Basically, if anyone shows up with quantities of a known-to-be-rate valve, chances are it's fake.

http://www.jacmusic.com/nos/images/Fakes/

[Barry]

NOS = "new, old stock". That is new, unused devices that are no longer made, but taken from stock before production stopped.

Thus the manufacturer's logo and label should be unworn and the pins show no sign of repeated insertion. They should also come with the original packaging and outer carton displaying the correct printing.

Some manufacturers went to some effort to prevent forgeries: Telefunken for example, had a 'bas relief' diamond moulded into the valve base between the pins. The printing of the manufacturer's logo used a chalky material which easily rubs off, so if you see one with the printing worn away, even if it is a genuine Telefunken valve, it is likely to have been used.