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Tube Amp question:TUBE replacements: explain MATCHED?

I don’t get the mystery behind it all.  I have a Cary CAD- 808…( I’m buying early before I need to replace)… so far, I have bought SOVTEK, in the EL 84, ( new)… I have bought 12AX7WC SOVTEK TESTED STRONG MATCHED PAIR (difference = 0%) TUBES=ECC83, and now I’m looking at (4) Lightly Used SOVTEK KT88’s… I…but I’d rather buy NEW KT88’s… does MATCHED mean I cannot buy another brand/make of a KT88? I believe this would fulfill needs to properly replace what I’m running now…I bought the amp with tubes installed… I am a novice… amp sounds great… however I need the plug-in to check the Bias, and I guess a meter? 

Does matched mean I have to stay with the same brand? I need (4) more KT88 tubes. Do they need to be (4) matched tubes?

SOVTEK only?

Thanks 

Dave
 

128x128moose89
audition__audio
1,550 posts
 

It is always a good idea to put matched power tubes in your amp or integrated. Do this even if it isnt required. You have a much better chance of similar longevity if you start out with matched tubes. Best to buy power tubes that have been burned in for 25 to 50 hours when possible. This is no guarantee that there tubes will age similarly but it doesnt hurt. Further there is no reason not to buy this way and no good seller will charge significantly more for matched tubes.

Post removed 
immatthewj
2,470 posts
 

@moose89 

just my two cents, but I’d work on getting the EL84s & the 12AX7s real good first (before or even IF you decide to try to find a way to go hog wild on the outputs).

Sounds like you have everything you need to check & adjust your bias, so good for you on that. The only thing that I would have done differently on that is to have bought a versatile multi-meter versus that fancy meter that Cary sells. But you can keep that in mind for next time in case the one from Cary ever breaks.

rodman99999
6,206 posts
 

     The nicest thing about buying that meter from Cary: it includes the same 3' test leads (with attached 1/4" plug), that came with my SLM100s.   

              Or: was it the Rocket 88 (Oldtimer's Disease strikes again)?     

                                                        Anyway:

     Would have been simple/easy to make my own, but I'm SO damned lazy: it was greatly appreciated! 

                    Then again: that IS a stiff price, for a mA dedicated meter.

immatthewj
2,470 posts
 

@rodman99999 

I was thinking that if Moose didn't have a multi-meter he could have killed two birds with one stone (always good to have a multi-meter handy) and if he did have a MM, he could have saved the $ on that one and just bought the leads.

But that's okay.  And if you've seen the pictures of the CAD 1205 MKII, that has bias meters built into the front face plate so one can be monitoring the bias all the time, and I can see where that would be nice.  I guess one could do the same thing with that fancy Cary meter?

You had a couple of SLM 100s?  How did you like them?  I once tried out a Mesa Barron and that got me wanting mono blocks and seriously considering the 100s.  I remember talking to Kirk Owens about them, & he sounded unusually (for him) animated.  I wound up buying a couple of secondhand ARC VTM 120s from a guy who was selling them via a listing in the back of Stereophile; those amps sure sounded good, but I used to cross my fingers & grit my teeth whenever I turned them on, so for the sake of reliability I bought my V12 in '01.

Oh well, ramble on. . . .

 

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