I have a Boogie Mark III, red stripe, simulclass, no reverb, with the original Boogie preamp and power tubes-Time to replace the tubes-6L6's and EL-34's inside/outside-Your tube suggestions are most appreciated-Thanks mucho!!
+1 But I prefer the sound of 4x6L6s. I replace the preamp tubes with some JJ 12AX7 and I like them. Cheers!
Another vote for the SED EL34/6L6 set-up. I really dig the 15 watt setting with those EL34's I have an eclectic mixture of NOS pre-amp tubes in mine...a MKIII "loaded" purple stripe Commentary, Swapping pre-amp tubes in these things is a MAJOR PITA! My fingers just can't get in there very well, even after removing the power tubes and PI tube. I've been known to just pull the chassis out!
I bought a Mark III Simul-Class new in 1986, (still have it), and I can tell you that NOS Sylvania STR415 6L6GC's straight across is the absolute best and will make that amp MAGIC! As far as preamp tubes go, NOS RCA 12AX7's are great, as are NOS GE's, or 80's NOS Chinese. RickO Clips: http://www.nowhereradio.com/artists/album.php?aid=3820&alid=-1 Gear: http://rickowens.4t.com/photo.html
RE: "NOS" (LOL!) Chinese 12AX7's I bought 6 of these about a year or so ago from Lord Valve. Yes, they do/did sound great in the MKIII, but 2 out of 3 in the MKIII went microphonic. I seem to recall tht "back in the day" the darn Chinese tubes didn't last very long, and I'd replace them with regularity.
Unless that amp has been modded the bias isn't adjustable. You should use power tubes with certain gain characteristics. That's part of the Mesa sales pitch - "never bias your amp, just buy our tubes" I would either get the tubes from a dealer that is familiar with the Boogie stuff and can give you the proper set, or have a bias pot installed.
sundaypunch brings up an importaint point concerning the Boogie fixed bias design. I'm sure they do it to promote selling their tubes. If you plan on experimenting with various tube types and brands, I highly recommend that you take the amp to a tech to have a bias pot installed so that you don't get any of that dreaded burning smell coming out of your amp. RickO
You do need to get the proper power tubes for the fixed bias to work correctly. If you buy Mesa tubes you will need to get the correct tube color codes. Mesa doesn't appear to have any of the Svetlana 6L6's. The Svetlana EL 34 (STR 442) is still on the website. I have not tried the Chinese 6L6' that they are currently using. If you decide to use their tubes you may want to give them a call and confirm what color code you need to use in your amp. Ask for Mike Bendinelli he's the resident Mark series guru. Their number is 707 778 6565. My favorite power tubes for my MK III simul are the old Mesa/ Phillips 6L6 (STR 415). Pretty hard to find these days. I've also used the Svetlana's and the EH 6L6's both work well. I've had good results with the JJ and EH 12AX7's as well.
nolenuttt - I just re-tubed my Boogie MKIII from head to toe two months ago and I've been in Tone Heaven ever since. First, for power tubes I inserted TAD "short-bottle" power tubes. These tubes have more of a compressed sound and a slight decrease in headroom but it exactly what I wanted. (http://www.mojomusicalsupply.com/cgi-bin/mojotone/4150010.html?id=JopkXAUc Then I contacted Bob at Eurotubes for my preamp tubes because alot of GPN members recommended JJ's to me and Bob is a big JJ dealer. http://www.eurotubes.com/euro-n.htm Bob - who will work with you every step of the way - recommended the following for my MkIII: an ECC803S's in V1, two graded high gain ECC83S's in V2 and V3, a standard ECC83S in V4 and a current balanced ECC83S in V5. His recommendations were right on the money! I played a show recently (out of town) and for the first time in my playing career (25+ years) I have been 100% satisfied with my TONE! In all honesty, my sound was so rich, sweet and creamy that I didn't want to stop playing. It certainly made me play my best and I achieved a level of musical nirvana that I've never previously experienced. Good Luck!
