Newbie Mark IIC+ question

[mdog]

I have a Mark IIC+ and I have a question about Simul-Class vs. Class A and how it relates to watts and speaker ohms.
It has Simul-Class/Class A switching, i believe 100W due to the 4 6L6 tubes.
First of all is Simul-Class/Class A the same as 100/60W? I don't believe it is but am not sure.

the manual says for 100/60 watt models they recommend using the 60W switch and plugging into the 4 ohm jack when running just a single 8 ohm speaker. They also say with just 60W models, when running a single 8 ohm speaker use the 8 ohm speaker jack.

My main question is what if you have the Simul-Class/Class A version, of which I believe is 100W, when running thru just a single 8 ohm speaker which position (simul-class or class A) and which speaker jack should I be running thru, 4 or 8 ohms.

 

[JOEY B.]

Read this site and you will gain much C+ knowledge.

http://homepage.mac.com/mesaboogie/welcome.html

 

[mdog]

I have read that site, but could not find an answer to my question. Any other mark iic+ users with simul-class 100 w versions?

 

[JOEY B.]

If you have a standard Simulclass C+, (not the series 300 Coliseum model) then your power ratings are 75 watts in simulclass mode and 15 watts in Class-A mode. When using a single 8 ohm speaker, either speaker jack can be used safely. Although Class-A with the 4 ohm jack sounds very sweet. 8)

 

[Boogiebabies]

That passage in the manual is about not blowing up speakers, not impedance matching. Mesa was assuming the user was not using a speaker rated to handle the power. With the C+, it only came with two speaker options. The EV-12L at 200W or the Eminence MS-12 at 150W. Many of us have more than one original example of each speaker type that has lasted since the amp was new. They have surely seen an idiot or two who have just cranked the amp without blowing the speaker.

 

[Buddy]

I would'nt worry about the impedence mismatch with a 4 or eight ohm load in simul or class "a " with these amps .

Go for the tone . 8)

It's 17 to 25 (watts) in class a . Dependin' ....with a used amp .
85+ with simul .

But 85+ BOOGIE watts is a lot different than

other amps 100 W .

BIG .

 

[mdog]

My C+ has a 12" Black Shadow MC-90 made by Celestion. Has a power capacity of 90 watts at 8 ohms. I was just a little concerned about what the manual says about the different versions of the amp. I would not want to blow a speaker. I have been using the 4 ohm jack and Class A when just using the one speaker. I do have a matching extension cab with a 15" EV speaker at which point I use both 4 ohm jacks and switch to Simul-Class.

And thanks for everyone who weighed in with reply's, i really appreciate it. boogie on