Help identifying this Mesa Boogie Amp

[diydidi]

Hi All.
Please see attached pics. Any idea what model this is??
I got it for repair today, so a schematic will also be appreciated.
Thanks in advance

[mort]

Looks like a mid 80's Mark IIB. Not 100% sure, there were variations within each model number too, iirc.

[Jazz P Bass]

Sure looks like a Mark IIB.
The Mark II was the Simul-class. The effects loop makes it a B.
Here is a MB page: UG Community @ Ultimate-Guitar.Com - The Only Boogie Mark Thread!!!!!!
And Wiki: Mesa Boogie Mark Series - Wikipedia, the free encyclopedia
Repair info: http://www.mesaboogie.com/manuals/Ma...int-Repair.pdf

[Jazz P Bass]

Oh, and here is the Rev B schematic.
Watch out for the possible Fetron.

[Enzo]

It has a pull switch on every control. I thought the MkIII started that. Did the MkIIC+ have pulls on ALL? I used to have a chart based on pull switches as a model identifier spotting guide.

[mort]

It has a pull switch on every control. I thought the MkIII started that. Did the MkIIC+ have pulls on ALL? I used to have a chart based on pull switches as a model identifier spotting guide.

I think most of the Mk III's had an EQ, but that's not to say they didn't make one without. That whole Mark series was just one mod after another, and options abound.

[diydidi]

Wow. You guys really know your amps. This one only has two 6L6 output tubes. Maybe not a IIB?

[Jazz P Bass]

Well, after reading Enzo's post, it may very well be an Mk III.
The Rhythm 2 footswitch was added as well as all of the pull pots.
The 2 6L6 tubes is an odd duck.
Most where 100 watt/ Simul_Class.
The EQ thing was an option.
Manual: http://www.mesaboogie.com/manuals/Mark%20III.pdf

[bob p]

as others have mentioned, the Mark series amps were highly customizable. back when Mesa first started off with the Mark I, all of the amps were made to order and all of the options on the amp could be ordered ala carte. because the EQ was a pretty expensive option, they made lots of the early Mark series amps without EQ. (I still have an original Mk I product packet, including a brochure, price list, and order form that I obtained by mail from the factory back in the Dark Ages.)

I'm thinking that you could order the Mark series amps with ala-carte features all the way through the Mark III models. I think that when they made the Mk Iv, all of what used to be available as options became standard equipment on the amps.

The variability of options in the MK I, II and III makes identification really difficult. As far as ID'ing this amp goes, It's possible that someone might have custom-ordered a Mk III with a 50-watt option and no EQ, but then i think it's also possible that Mesa might have also offered some of the stripped-down mark series amps under different model designations in later years. It can get really confusing.

One thing that you might try doing is calling Mesa customer support with the serial number that's on the back of the amp. They'll be able to tell you the exact model, and they should be able to provide you with a schematic. That'd remove all of the guesswork.

[JGP500]

Hi All.
Please see attached pics. Any idea what model this is??
I got it for repair today, so a schematic will also be appreciated.
Thanks in advance

diydidi, sorry I'm late to the party but I just ran across this thread. This amp is without a doubt a Mark 3. It's a purple stripe which it the 1st revision of this amp. It's either very late 1985 or early 1986. The first Mark 3's were "no stripe" then they went purple-red-blue-green each time slightly changing the unit and doing improvement mods on them. Your amp is a 60 watt model that's identifiable by only having 2 power tubes (6L6's). 100 waters have 4 power tubes, again 6L6's and simulclass has 4 power tubes but 2 are 6L6's (inside sockets) and 2 are EL34's (outside sockets) although you can use 6L6's in the outside sockets as well it's just a matter of tone preference. You also have the "export" power transformer which you need in countries where 117 volt isn't the norm. It's been said that the export transformer helps to produce a better sound but that generally applies to the simulclass heads and some say it's more noticeable in the Mark 2 C+'s But givin the choice, I'd take the export transformer over the the stock 117 volt as I feel it makes for a better tone, even in a 60 watt mark 3. All in all you have you a nice amp there, I feel the mark 3's are under rated, I can get mine to sound fairly close to my mark 2 C+'s and the C+'s are considered the holy grail of boogie Mark amps. ENJOY

[JGP500]

Hi All.
Please see attached pics. Any idea what model this is??
I got it for repair today, so a schematic will also be appreciated.
Thanks in advance

diydidi, sorry I'm late to the party but I just ran across this thread. This amp is without a doubt a Mark 3. It's a purple stripe which it the 1st revision of this amp. It's either very late 1985 or early 1986. The first Mark 3's were "no stripe" then they went purple-red-blue-green each time slightly changing the unit and doing improvement mods on them. Your amp is a 60 watt model that's identifiable by only having 2 power tubes (6L6's). 100 waters have 4 power tubes, again 6L6's and simulclass has 4 power tubes but 2 are 6L6's (inside sockets) and 2 are EL34's (outside sockets) although you can use 6L6's in the outside sockets as well it's just a matter of tone preference. You also have the "export" power transformer which you need in countries where 117 volt isn't the norm. It's been said that the export transformer helps to produce a better sound but that generally applies to the simulclass heads and some say it's more noticeable in the Mark 2 C+'s But givin the choice, I'd take the export transformer over the the stock 117 volt as I feel it makes for a better tone, even in a 60 watt mark 3. All in all you have you a nice amp there, I feel the mark 3's are under rated, I can get mine to sound fairly close to my mark 2 C+'s and the C+'s are considered the holy grail of boogie Mark amps. ENJOY