Simul Class?

[mac]

Hi all,
How would you describe the sonic difference created by the Simul-Class option? Is this a drastic difference? Is it always heard, or only at really high volumes?
I have got a Mark III Super Sixty Combo and would like to ask whether it is possible to convert it into a SimulClass amp? Does Mesa offer a kit to qualified technicians for doing this? Would you think it would be worth to invest into getting this option?
Thanks in advance for your opinion!
mac

 

[mesa115]

I think this has to do with EL84 tubes. I thought it was some way to get extra juice out of the smaller wattage EL84 units, like Subways or DC2's

I did not think you had that option on 6L6 tube amps.

Correct me out there if I'm wrong.

 

[chedgeco]

The Simul-Class option uses four tubes to generate 75 or 85 watts. I don't think this can be done with just a 60 watt two tube amp.

One thing I've been thinking about is using THD Yellowjackets in my recently acquired DC5 to get the 50 watt output power down to about 20 watts. If you're looking to get less watts then you could do the same. If you are just interested in Simul-Class then you will have to get one of the Simul-Class Mark series amps.

Chris... 8)

 

[VJIII]

Hi all,
How would you describe the sonic difference created by the Simul-Class option? Is this a drastic difference? Is it always heard, or only at really high volumes?
I have got a Mark III Super Sixty Combo and would like to ask whether it is possible to convert it into a SimulClass amp? Does Mesa offer a kit to qualified technicians for doing this? Would you think it would be worth to invest into getting this option?
Thanks in advance for your opinion!
mac

Hi Mac. I own two Mark III heads: a red stripe 60/100 and a blue stripe with simulclass. There is definitely a difference with simulclass, personally I think it's mostly because of the EL34's used in simulclass models. My favorite is definitely my red stripe with no simulclass, but remember that's just my opinion, not yours . (I think it's mostly because I really don't like the sound of EL34 tubes, I sometimes substitute in 5881's in the EL34 slots.) I would really recommend trying to hear a similar simulclass amp before spending something like $300 plus $100 shipping to mod your amp. Be sure you really want it! 60 watters rock too 8)

 

[JazzRules]

Hi all,
How would you describe the sonic difference created by the Simul-Class option? Is this a drastic difference? Is it always heard, or only at really high volumes?
I have got a Mark III Super Sixty Combo and would like to ask whether it is possible to convert it into a SimulClass amp? Does Mesa offer a kit to qualified technicians for doing this? Would you think it would be worth to invest into getting this option?
Thanks in advance for your opinion!
mac

Not worth the trouble vs buying a Simuclass amp. You'd need an entire chassis, electronics to support the 2 extra tubes, larger transformer, more caps etc etc.

Simul-Class means the inner pair of tubes run "Class AB" and ONE triode of the outer pair run in "Class A".

You'd have to audition a Simul-Class Mark III for a few hours (with the same speaker configuration!!!) to evaluate if it's worth it to you. Nobody can tell you "it's worth it". Well perhaps, if you're easily manipulated.

I have a Simul-Class Mark IV and a 60 watt Mark IIC+. I never use the Simul_Class feature, as I opt for Class A, Full Power, Triode mode.

 

[Kgry]

Yeah I guess you'd have to test it out but I love Simul-class and always run my Mark III that way. I like both qualities of EL34's and 6L6's and together I think they sound great.

 

[Joey707]

I use 6L6's in all four sockets of my MK III simul's. After using 60 watters and 100 watters I settled on the simul-class models. It's a somewhat softer sound. I also think they sing a little more than the other models. If you use 6L6's in all four sockets it's a very fat sound. Just my opinion of course, your results may vary.

 

[Grandor]

Simul-class is a feature which enables you to either use 2 el34s and 2 6l6s in Class A blended with A/B.

Or 4 6l6's (ie. petrucci, metallica etc) with 2 running at a different plate voltange. This runs two in an approximation of Class A, and 2 in class A/B.
Thereby capturing the best of both worlds.

 

[MesieBooga]

Or 4 6l6's (ie. petrucci, metallica etc) with 2 running at a different plate voltange. This runs two in an approximation of Class A, and 2 in class A/B.
Thereby capturing the best of both worlds.

So they're running 4 6L6's in Simul-Class mode?

 

[Grandor]

From my understanding...

Yes.

 

[Joey707]

One other thing that should be mentioned, in the simul-class MK II's and MK III's the outer pair of tubes is running in triode. Starting around 1990 the outer pair is wired in pentode. This would pertain to green stripe MK III's and all MK IV's. This ups the power to 85 watts.