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
Post removed 

@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.

     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.

@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. . . .

 

@immatthewj -

     I've looked for/at the smallest ammeters and (thus far): haven't found anything I could mount anywhere on my SLMs' chassis, for the convenience of not reaching for my Fluke.

     Hanging a couple on the amp stands and hard-wiring to the Bias jacks, would be a possibility, but: I'm SO lazy.

     Besides, it seems: with a good quad of output tubes in each monoblock, their relative biases seldom change.     Only: slight bias variations, consistent/the same in both, according to what's coming from the wall.

     The SLMs were my step, following the Rocket 88, which didn't have the juice to satisfy my SPL Jones (inefficient speakers, at the time).     No need to look further, as the SLMs' excellent transformers and circuit design made adequate power and the realism/presentation I sought, an easy reach, with judiciously chosen parts.   

     They were treated early on, to better RCAs, 5-ways and IXYS HEXFREDs.   Since: every cap has been upgraded (ie: Duelund cast-PIOs for coupling, ClarityCap ESAs in the B+, etc ).

     Of course: the optimum, NOS 6SN7 search was another enjoyable, illuminating and fun-filled journey.

                        Yeah: I'm FULLY invested in the SLMs, with NO regrets!

                                                     Happy listening!