Trey's Boogie Class Resolved

[Heady Jam Fan]

To the best of my understanding, there is an unanswered question regarding the class of Trey's Mark III Red Stripe: Simul-Class or non-Simul-Class?

Its pretty commonly accepted it is a Red Stripe Long Head. The long head amps have the power setting switch on the front. Even the Simul-Class long head amps say "Full Power" and "1/2 Power" like the non-Simul-Class amps, while short heads says "Simul-Class" and "Class-A." We can see pics of Trey's amp set to "1/2 Power" and pics that seem to show 4 6L6 tubes in his amp, indicating he is using 2 6L6 tubes at a time. Does the fact he has 4 6L6 tubes in his amp indicate he has a non-Simul-Class amp? Or does he follow Mesa's old suggestion the Simul-Class amps can handle 4 6L6, even though they eventually retracted that statement?

I think there is an answer to this question. Since the faceplate on Simul-Class long heads do not indicate the class of the amp (rather they say full or half power), Mesa stuck a small plate/sticker on the back of the chassis to the left of the power cable indicating the amps class. I believe they did this on Simul-Class amps only. You can see this sticker on Trey's amp:



But not on this non-Simul-Class amp:



Close-up of Simul-Class sticker:



Does this confirm Trey's amp is Simul-Class?

[tsbot]

Dang - good investigating.  I'm almost 1/2 tempted to email Paul and ask, but I don't know, he's seems out of the phish thing a little. 

Can you explain the wattage of Simul vs non and 1/2 power etc?   This may make me hold out for a red stripe!

[Heady Jam Fan]

You know, I always wondered if Trey's was a Simul-Class, and it just clicked in my head when you sent me a pic of that long-chassis Purple Stripe; it was like I had the answer, but hadn't put the pieces together! Lol.

Out of the Mark III amps, there are several different output power/wattage options. I could be missing some...

- 60 watt 2 6L6 versions
- 180 watt 6 6L6 Coliseum*
- 60/100 watt 4 6L6 Non-Simul-Class (60 in 1/2 power mode)
- 15/75 watt 2 6L6 2 EL34 Simul-Class (15w in Class-A, 75w in Simul-Class)
- 25/85 watt 2 6L6 2 EL34 Simul-Class Green Stripe (25w in Class-A, 85w in Simul-Class)**
[Of course the last two of the above amp configurations could be run with 4 6L6's upping the power, but I'm not certain what the wattage would be.]


*The Coliseum might have been available in Simul-Class; 2 of the otherwise 6 6L6 tubes would be EL34's. I think it had a full / half power mode switch. but it would always be Simul-Class (never Class-A). Not sure of the wattage
**The Green Stripe runs the EL34's as pentodes rather than triodes, which is more efficient resulting in 10 more watts of output.

[tsbot]

So would that entail Trey is using 1/2 power mode and is running less than 25 watts?  What would the wattage be on the Purple Stripe Simul-Class pic I sent you?  Because I am looking for a 60 watt amp - which would be best?

[Heady Jam Fan]

So would that entail Trey is using 1/2 power mode and is running less than 25 watts?  What would the wattage be on the Purple Stripe Simul-Class pic I sent you?  Because I am looking for a 60 watt amp - which would be best?

Assuming I'm correct and Trey's amp is a 15/75w Simul-Class amp, setting the switch in the "1/2 Power" mode would be the same (just labeled differently) as "Class-A" on the short heads. That would be 15 watts except for the fact that it appears Trey uses 6L6's in place of the EL34's. I'm not sure what the wattage would be with 6L6's in place of the EL34's in Class-A mode. Depending on the amp, 6L6's can put out about 2x as much power (in watts) as EL34's, so maybe that setup would max at 30 watts? Just a guess.

The Purple Stripe would be exactly the same in this regard.

I've never put 6L6's in the outter (EL34) slots of my Mark III. Maybe I should try it some time, but I never use the Class A mode with EL34's, so  I assumed I would still prefer Simul-Class over Class-A even with 6L6's instead. I also didn't want to burn out more tubes faster (putting 6L6's where EL34s are supposed to go would burn out the 6L6's faster, so you want to buy ones that run colder).

One thing I did do for a bit was running the amp in Simul-Class mode without the EL34's (I pulled them out). This runs the 6L6's a bit hotter, which should be okay since Mesa's are biased cold anyway. This would make the amp similar to the 2 6L6, 60w version of the Mark III except a somewhat different output transformer and hotter bias - the amp would max at about 60 clean watts hypothetically. However, the impedance the output transformer expects to see changes. It would now expect an 8ohm load in a 4ohm jack, or a 16ohm load in an 8ohm jack. So leaving an 8ohm speaker in the 8ohm jack would be a (safe) mismatch that would decrease the amps volume/efficiency a bit. You could plug the speaker into the 4ohm jack, but I believe this wouldn't fully utilize the OT.

If you want a 60 watt Mark-series amps, there are a lot of options. This includes 60w Mark III's (with 2 6L6's), I pretty sure they made Mark II's in that configuration as well, the various iterations of Mark I reissues are also in this configuration I believe including the SOB and Kingsnake (maybe not bad options if you only want the clean channel).

[seriesnuns]

I have a simi purple class. I run all 6l6 from eurotubes. He told me if I run half power just rotate them every so often.

I do like the sound better with 6l6 on the outside.

I've had mine in for a year with normal use and haven't swapped them yet.

[Heady Jam Fan]

^ Good to know. Maybe I will try some 6L6's soon!

[Helping Friendly]

Great job Heady! I've been asking myself this question for years. Now if I can only get class A to sound like that. Lol.
As far as tubes, I started with the mix, then all 6l6. Now I'm back to the mix. On class A i like all 6l6's. Full power I favor the mix.

[Heady Jam Fan]

Great job Heady! I've been asking myself this question for years. Now if I can only get class A to sound like that. Lol.
As far as tubes, I started with the mix, then all 6l6. Now I'm back to the mix. On class A i like all 6l6's. Full power I favor the mix.

Interesting. I've been buying all my Mark III tubes from Doug's Tubes. I asked him which 6L6' would fair the best in the EL34 position. The only tubes he thought of were a matched pair of Svetlana 6L6's. This particular matched pair was out of spec (low current draw IIRC) - the only reason that he didn't return them is because he bought a huge bulk and by the time he tested that pair, he was past the return date. I didn't ask specifically, but I take this to mean that he wouldn't really suggest running 6L6's in place of EL34's.

[Walker done done]

Anyone know what type of tubes Trey uses?

[Helping Friendly]

Anyone know what type of tubes Trey uses?

That's the next thing we gota find out! Power tubes as well as pre! I'm guessing expensive and really hard to find ones. Lol

[Down_With_Sco]

There was something that said he was using sovteks in the 90's.

[Heady Jam Fan]

Thats what I was thinking, but I wasn't real confident in that either.