EL34 is just the British designation for 6L6 which you already have in your Boogie. The Brit's also use ECC83 as a designation for 12AX7. I would not suggest using anything other than EL34/6L6 in your Boogie and I would stick with only Boogie brand tubes. Boogies have a fixed BIAS (it can't be adjusted) and the tubes they sell fall into a tight tolerance range that works best at this BIAS setting. Alot of other tubes fall outside of this range and it affects the sound in a negative way since you can't adjust the bias voltage for that tube. I tried other tubes in my Boogie and it sounded like crap! You might just luck into 4 6L6's that all fall into this range but I doubt it. This is why Boogie tubes are sold in matched pairs and are color coded for the range they fall into. This isn't so your forced to buy their tubes, it's so all Boogies maintain the same voice from amp to amp.

I second that, I have owned a dual rectifier since 1992. I had a friend in another band at the time that went ahead and thru EL34's in his rectifier..

One word... Yuck... Stcik to 6L6's in the boogie, they rip. If you want a marshall type sound go out and get a Marshall..

Not to be biased, but JCM 800's and the older Marshall heads and the old Marshall Speaker cabs blow most of the new Marshall stuff out of the water.. (except the 30 aniversery stuff)

JCM 900 cabs were garbage as well.

I have owned 3 boogie amps over the last 10 years a Studio .22 combo, Mark III head and an older Dual Rec, ALL using Boogie and/or Svetlana 6L6's and in the last year I decided I wanted more of a hi gain / vintage - less modern sound from my dual rec, such as yourself. I tried a few different brands of tubes including the boogie EL-34's (which, I wasn't very impressed with) and ended up using JJ's EL-34's and I absolutely love them. I was ready to get rid of the amp but, because I was able to find the "right" combination, it's back to being my favorite amp. I play in a indie/rock band using a Les Paul and old hiwatt cab with 30watt celestions and I couldn't be happier. So imo, I would go for it and maybe try using a different guitar/cab combination with it. I have a phat tone and can definately tell that the upper harmonics jump out at me more,making my amp sound splendid. Hope this helps.

A Switch by a Different Name

[quote=Big_D]EL34 is just the British designation for 6L6 which you already have in your Boogie. The Brit's also use ECC83 as a designation for 12AX7. quote]

While you are correct about the ECC83 being the same as a 12AX7 the 6L6 and EL34 are completely different tubes with different bias and voltage requirements. They should never be used in place of eachother without proper changes made to the circuit by a technician. The Dual Rectifier has this option built in to it on the back and you should never flip the switch while the power is on nor should you ever put it in the opposite position of what tubes you are using. Now maybe the amp will work if you use the wrong tubes but it is sure to sound like shit and potentially cause damage to the amp. Now, you CAN use a 5881 in place of a 6L6 without modification as this is the mil spec version of the tube. You can also make minor changes to the circuit and use a KT66 or KT88 for more power and a sharper sound (as long as your power transformer can supply the extra power) , this is one of the many mods that Hendrix was known to use. But whatever you do, don't just place any tube that will fit in the socket into an amp you care about. Not that experimentation isn't good, I find myself preferring the lower gain 12AU7 and 12AY7 in the first stage of my HIWATT and in my Chandler Tube Driver but these tubes run at the same specs as a 12AX7 with less gain. Before you spend a $100 on some different tubes that could blow a $1000 amp, you should talk to a tech to make sure everything will work properly in your amp and any reputible tech will be able to make the necessary changes for (most) any set of tubes you would like to try out.

While you are correct about the ECC83 being the same as a 12AX7 the 6L6 and EL34 are completely different tubes with different bias and voltage requirements.

Ryan, You are correct the 5881 is the British designation for the 6L6 not the EL34. In my haste to respond I began typing before my brain was in gear. Thank you for correcting my mistake, I apollogize if I misled anyone.

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