Mark III stuff

[King Tone]

Ohm load question...
I have a green stripe mark III simulclass head. If I want to run a 16 ohm 1x12 cab will that work? The mark III has only 4 and 8 ohms listed. Do I need to run it at the class a setting and will that change the load. I have read the manual but it is a little vague.

What is the actual wattage of the mesa green stripe simulclass? 100/60? I have read that the power drops to either 25 or 15 watts if the switch has been turned to class a...I thought it was 100 going down to 60..?

One more, I am confused about the serial number. Mine has a green stripe but maybe a different serial number than what I thought it would. Any ideas? Thanks!

 

[CoG]

Ohm load question...
I have a green stripe mark III simulclass head. If I want to run a 16 ohm 1x12 cab will that work? The mark III has only 4 and 8 ohms listed. Do I need to run it at the class a setting and will that change the load. I have read the manual but it is a little vague.

yeah, plug it into the 8 on any class setting. It'll be fine. This is called a "safe mismatch." In a perfect-simulated-circuit-world this is bad for the amp, though not nearly as bad as mismatching the other way (output ohms >cab ohms.) They probably fudged it in the manual to avoid pedantic complaints from guys who are technically correct, real-world irrelevant

In the real world the transformers on Mesas and other commercially built amps are perfectly capable of handling this for hundreds or thousands of hours without any ill effects you'd notice; in fact, one of the Mark-series "tone recipes" is to plug an 8-ohm cab into the 4-ohm out to get a little bit of compression and a slightly darker tone.

 

[King Tone]

Ohm load question...
I have a green stripe mark III simulclass head. If I want to run a 16 ohm 1x12 cab will that work? The mark III has only 4 and 8 ohms listed. Do I need to run it at the class a setting and will that change the load. I have read the manual but it is a little vague.

yeah, plug it into the 8 on any class setting. It'll be fine. This is called a "safe mismatch." In a perfect-simulated-circuit-world this is bad for the amp, though not nearly as bad as mismatching the other way (output ohms >cab ohms.) They probably fudged it in the manual to avoid pedantic complaints from guys who are technically correct, real-world irrelevant

In the real world the transformers on Mesas and other commercially built amps are perfectly capable of handling this for hundreds or thousands of hours without any ill effects you'd notice; in fact, one of the Mark-series "tone recipes" is to plug an 8-ohm cab into the 4-ohm out to get a little bit of compression and a slightly darker tone.

Having said that, do you think my tone would be a little brighter if the ohms were "perfectly" matched? What about louder with that match? I have another amp (different brand) that sounds just right if matched but sounds a little bit odd mismatched. Just wondering how this affects the mark III. To be honest, with the cab I am trying, it probably sounds the best I have heard it, so far.

 

[edward]

Yup. With a certain cab, I plug that (8ohm) into the 4ohm jack of my III Simul head ...shaves off the top end for a specifically bright guitar and cab combination.

Edward

 

[King Tone]

So guys, what about the wattage ratings?

Oh yeah, and the serial number..?

 

[AustinK]

i believe it is 25 watts in class a as it is in pentode not triode.

For the serial number try the search function. I remember someone having a thread on it.

 

[edward]

AFAIK, the Simul greens are 85/25watts because the outer pair are wired Pentode; previous stripes are 75/15w because of triode.

Edward