Mark III

[bottebelott]

Hey everyone.

A guy in my town is selling a Mark lll blue stripe simul-class 4x6l6. 120W/60W with EQ and reverb.
Provided it is in good condition, how much is one of these amps worth? It's hard to find useful information about this, since there seems to be so many different versions of the amp, and they are worth different money.

H.

 

[Agustín Collia]

Hey everyone.

A guy in my town is selling a Mark lll blue stripe simul-class 4x6l6. 120W/60W with EQ and reverb.
It's hard to find useful information about this, since there seems to be so many different versions of the amp, and they are worth different money.

H.

First off, the guy should (if he hasn't already) do a bit of research and make it clear whether it's Simul Class (Simuls are 75/15 watts) or 100/60 (assuming it's a Blue Stripe, if it happens to be a Green Stripe it undoubtedly is Simul Class as there were no 100/60 watt Green Stripes made).
Then, depending on whether it's a head or a combo it could be worth a bit more or less, but typically, Mark IIIs sell for US$ 600/1200, 900 being the most common ball park. The thing to take into consideration is that different stripes don't command a different price, as they all are different incarnations of the same amp. What does command a higher/lower price is the state/wear of the amp, whether it was serviced recently or not (if ever), etc.
Good luck!

 

[lowercasee]

I just picked up a Mark III blue stripe combo with EQ and reverb from Music Go Round and I paid $850, if that gives you any help. The switch on the back toggles between class A / Simulclass, but it has 4 6L6GC's in it so I'm not sure if it's the 15/75 or 60/100. Either way, it sounds incredible!

 

[mesaboogie6L6]

75/15 is simul-class, no such thing as a 100 watt simul.

 

[lowercasee]

So does the switch on the back of the non-simul say 60/100 instead of class a / simulclass? I will pull the chassis and check the transformer to be sure.

 

[MrMarkIII]

Yes, the switch on a 60/100 model will say "60/100". Most, if not all wide heads will have this switch on the front panel. To add to the confusion, these say "Full/Half Power". They are still either 75/15 (Simul-Class) or 60/100. The wide, or "long" head, is identified by eight knobs on the front panel. The Reverb knob is moved from the back panel to the front.

The very last version of the Mark III was the Green Stripe. They are ALL Simul-Class and were 85/25, with ten more watts, because the outside tubes were also wired pentode, like all inner sockets on all Mark III's. Older Mark III's were triode on the outer sockets.

Finding 4 x 6L6's in a Simul-Class is not unusual. That was the point, that you could switch between EL-34's and 6L6's in the outer, "Class A" sockets. At some point in the middle 90's, Mesa recommended (in the manual) against 6L6's in the outer sockets because of poor tube QC. Not Mesa's QC, the tube manufacturer's QC. This is no longer true..

 

[dlpasco]

Yes, the switch on a 60/100 model will say "60/100". Most, if not all wide heads will have this switch on the front panel. To add to the confusion, these say "Full/Half Power". They are still either 75/15 (Simul-Class) or 60/100. The wide, or "long" head, is identified by eight knobs on the front panel. The Reverb knob is moved from the back panel to the front.

The very last version of the Mark III was the Green Stripe. They are ALL Simul-Class and were 85/25, with ten more watts, because the outside tubes were wired pentode. Older Mark III's were triode on the outer sockets.

Finding 4 x 6L6's in a Simul-Class is not unusual. That was the point, that you could switch between EL-34's and 6L6's in the outer, "Class A" sockets. At some point in the middle 90's, Mesa recommended (in the manual) against 6L6's in the outer sockets because of poor tube QC. Not Mesa's QC, the tube manufacturer's QC. This is no longer true..

Do you know how the inner sockets were wired on the older Mark IIIs? Just curious.

It's nice to know that the 6L6 warning is less relevant these days, I like playing with all 6L6s in my blue stripe Mark III and felt like I was taking some risks doing so.

 

[lowercasee]

Yes, the switch on a 60/100 model will say "60/100". Most, if not all wide heads will have this switch on the front panel. To add to the confusion, these say "Full/Half Power". They are still either 75/15 (Simul-Class) or 60/100. The wide, or "long" head, is identified by eight knobs on the front panel. The Reverb knob is moved from the back panel to the front.

The very last version of the Mark III was the Green Stripe. They are ALL Simul-Class and were 85/25, with ten more watts, because the outside tubes were wired pentode. Older Mark III's were triode on the outer sockets.

Finding 4 x 6L6's in a Simul-Class is not unusual. That was the point, that you could switch between EL-34's and 6L6's in the outer, "Class A" sockets. At some point in the middle 90's, Mesa recommended (in the manual) against 6L6's in the outer sockets because of poor tube QC. Not Mesa's QC, the tube manufacturer's QC. This is no longer true..

Wow, thanks for the info. Pretty cool to know that the amp is Simul-Class. I think I'm going to get some EL34s and try them in the outer sockets. It sounds great now but for the small cost of a few tubes, it's worth a shot. By the way, my amp is a combo so the switch is on the back.

 

[MrMarkIII]

Yes, the switch on a 60/100 model will say "60/100". Most, if not all wide heads will have this switch on the front panel. To add to the confusion, these say "Full/Half Power". They are still either 75/15 (Simul-Class) or 60/100. The wide, or "long" head, is identified by eight knobs on the front panel. The Reverb knob is moved from the back panel to the front.

The very last version of the Mark III was the Green Stripe. They are ALL Simul-Class and were 85/25, with ten more watts, because the outside tubes were wired pentode. Older Mark III's were triode on the outer sockets.

Finding 4 x 6L6's in a Simul-Class is not unusual. That was the point, that you could switch between EL-34's and 6L6's in the outer, "Class A" sockets. At some point in the middle 90's, Mesa recommended (in the manual) against 6L6's in the outer sockets because of poor tube QC. Not Mesa's QC, the tube manufacturer's QC. This is no longer true..

Do you know how the inner sockets were wired on the older Mark IIIs? Just curious.

It's nice to know that the 6L6 warning is less relevant these days, I like playing with all 6L6s in my blue stripe Mark III and felt like I was taking some risks doing so.

All the inner sockets are pentode (60 watt, 60/100, Simul-Class). The inner sockets always yield 60 watts.

No, you can't remove the tubes from the outer sockets, run in Simul-Class, and get 60 watts. The choices are 15 or 75 watts (25 or 85 in a Green Stripe).

You CAN get away with running in "Class A" (15 watts, outer sockets only) and remove the two tubes from the inner sockets. But why? You still don't want to switch to Simul-Class while doing this stunt. This maneuver will, however, get you through gig if an outer socket tube fails.
Switch to "Class A", and replace the failed outie with an innie. This is why one carries spares.

If you run *ALL* 6L6's *AND* run in "Class A" 15 watts *ALL* the time, you might save a touch wear and tear on the unused center tubes by rotating them with the outer socket tubes. Fun for those who live on the edge.

I'd much rather retain the capability to switch to FULL POWER!!! at a moment's notice when needed.

 

[scelerat]

What's the difference, if any, in tone and power, between EL34s and 6L6es in SimulClass mode?

 

[MrMarkIII]

Power is the same, 75 watts (85 for greenies). Tone is the difference between 6L6's and EL-34's.
Generally speaking, 6L6 is the Fender sound. EL-34 is the Marshall sound.
Mark III Simul-Class is the Boogie sound.

 

[gts]

What's the difference, if any, in tone and power, between EL34s and 6L6es in SimulClass mode?

Tone depends on the tubes involved as well.
Get some Mesa labelled STR-416's (aka relabeled Sylvania EL34's that have Mesa specs) you wont be disappointed!
In my experience, typically El34's have less bottom end than 6L6's. The 416's are the exception.
Generally speaking EL34's have a bit more 'chime' than 6L6's whereas 6L6's have a warmth to them that EL34's don't have.

Power wise for 6L6's and EL34's do a google search, there's lots of info out there like on this page:
http://www.thetubestore.com/Tubes/6L6-5881-Tube-Types
and this one:
http://www.premierguitar.com/articles/Everything_You_Ever_Wanted_to_Know_About_Output_Tubes