Greetings

Wondering myself about changing the 6l6's with c winge's still need to be re bias on the sv mk ii

Thanks john

Hi. I'm new to the Spider valve but really liking the amp. However I have been a tube amp guy for a long time. So I'll tell you since it sounds like you're new to tube amps and all. Yes using different tubes can and will make a HUGE improvemet in the sound of your tube amp. Also the "OEM" or original equipment manufacturer tubes that ship with MOST amps out there (not just Line 6) are not the best sounding tubes avialable. They ship in most amps becasue they are inexpensive. In other words there are much better sounding tubes than the Sovteks that your amp came with.

Some of the best tubes being made: for preamp tubes the the JJ ECC83 or Tung Sol 12AX7. For Poweramp tubes the JJ 6L6GC or the SED "WInged C" (used to be Svetlana) are the best. In my opinion the JJ 6L6 has near NOS sonics at a working man's price. There are also other good tubes out there but in my experience those are the best. Best thing to do is to try a bunch and see what you like.

Note: when changing poweramp tubes you should have your amp biased for the new tubes. If you are a novice you should have the biasing done by a professional amp Tech because the voltages inside an amp can kill you.

Remember opinions vary, and these are just opinions...

The tubes, both 'ax7s and 6l6/5881s can make quite a difference in tone, especially to the discerning ear.  I played a simple guitar-cable-amp setup, no effects, for well over a decade before getting a Spider Valve.  Primarily a S-S-H Strat thru a MkIV Boogie.  The power amp tubes make a greater difference in tone IMHO, especially in the Spider Valve.  Going to the JJ's or the SED's will definitely change your tone.  The SED's give a vintage tone, which is a mellower tone.  The JJ's are very bold and in your face.  When I was plaing primarily just blues, the SED's were the way to go for me.  I didn't use the JJ's for too long (maybe 6 months), just because it wasn;t the tone I was looking for - I agree with peewee here in that if I were playing metal most of the time I might go with those.  The Sovtek 6L6WXT+'s are an upgrade (sonically) to the 5881/6L6WGC's that come stock in the Spider Valve - it is one of the best all around sounding tubes around, especially for the price.  I've tried the SED's in the spider valve and wasn't pleased.  The 6L6WXT+'s sound great.  I also liked the TungSol 5881's but stopped using them when I realized they were not rated quite high enough to use in our amp safely.  I haven't tried the new 6L6 TungSol's but will eventually.  I also did not like the EH 6L6's - again too mellow sounding for this amp.  IMHO we want a tube that will cover the same tonal spectrum as this amp does, which is quite a spectrum.

The Mesa tubes are just heavily screened tubes from the same manufacturer's your used to hearing.  For quite a while now the SPAX7's are heavily screened Chinese 12ax7b's.  Their other 12ax7's are also Chinese, just not as quiet as the SPAX7's.  I'm currently running the Chinese 12ax7's and am very happy wiht the tone.  I've also been happy wiht the EH and TungSol 12ax7's.