Anyone Else notice this on the Mesa Website

[litesnsirens]

On the Mark V page if you look at the "Features" section, it says that in 45 watt mode the Mark V runs in class A/B but on the "Full Story" section it says that 45 watts runs class A, pretty sure the manual says class A as well.

 

[SteveO]

Pretty sure that only 10W is class A, 45W is A/B.

 

[litesnsirens]

Well 10W is definitely single ended class A. 90 Watts is simulclass which is a mix of class A and class A/B, perhaps 45W generated in class A and then doubled in class A/B or vice versa. Which leaves the 45W mode, which is cutting 2 of the power tubes out of the circuit, so it's either cutting the tubes that are running class A or the tubes that are running class A/B... There are two opposing explanations on the mesa site... I haven't had the chance to call and ask.

 

[ifailedshapes]

I know this manual backwards and forwards. The 45 watt power section is class A, but not the "true" single-ended class A.

 

[phyrexia]

There were two versions of the manual - one calls it "Class A" the other calls it "Extended Class A".

It can't be any sort of Class A if it's really 45w :lol: Close enough for rock and roll though.

 

[wil]

Hi,

Yep, different versions of the manual. Just take a look at page 31 (35 in the PDFs).
Here is an old version of the manual:
http://bugfactory.org/~wil/mesa/MkV_090423.pdf
and the current one:
http://bugfactory.org/~wil/mesa/MkV_090813.pdf

Wil

 

[litesnsirens]

And neither one of the manuals says what it says here on the website.

Simul-Class™ Power Amp (Patents 4,532,476 & 4,593,251) featuring Multi-Watt™ (Patent Pending) and Duo-Class™ (Patent 7,173,488) technologies which provide three power and three operating class options that are channel assignable via 10/45/90 Watt Power Switches: Choose 2 power tubes operating in pure vintage Class A (single-ended), producing 10 Watts - 2 tubes running in time-honored Class A/B producing 45 Watts or 4 tubes running in Mesa’s legendary, patented Simul-Class Power that blends the best of Class A and Class A/B simultaneously to produce 90 Watts of pure tonal magic / 4x6L6 (or 4xEL-34), 7x12AX7, 1x5U4

Above quote taken from this webpage
http://www.mesaboogie.com/Product_Info/Mark_Series/mark5/mark5.html#p7GPc1_2

I was originally just noticing the misprint on the website... It's been my belief from the get go that the manual is most likely correct and the webpage is a misprint.

Wouldn't it be great to have one more switch on the back of the amp to use either the inner 2 tubes or outer 2 tubes and choose between 50 watts of A/B or 45 watts of "extended class A" Not that there isn't enough flexibility with this amp as it is... just saying....