Mark III- Simul-class??????

[LUCRETIA]

Hey guys is the MK III combo(Black DOT) is a simul-class amp??I'm quite confused with this thing?How to know if its simulclass? :?

 

[screamingdaisy]

If it has a switch on the back that says "Simul-Class / Class A" on the back, it's a Simul-Class amp.

 

[Boogiebabies]

 

[Scotland]

If it has a switch on the back that says "Simul-Class / Class A" on the back, it's a Simul-Class amp.

Yep, without that switch it's either a 100/60 or a Super 60 with only two output tubes.

 

[tim6string]

Boogiebabies is correct, I contacted Mesa on this. A Long chasis with a simul-class sticker on the back and a 100/60 switch on the front is probably a simul-class even through it does not have the simulclass class "A" switch. So your best bet beyond that is to check the part numbers.

 

[LUCRETIA]

Thxs for reply.I'm still waiting for the amp,and the owner only said its 75watts.And its combo black dot.

 

[Boogiebabies]

 

[Wico]

Hey Guys!
I've recently bought a used Mesa/Boogie Mark III long head. My Mark III head is blue striped and has the "MB" letters written by ink-pen on the chassis. It is export version, there is a main voltage selector on the back.

I was not quite sure if it's a simul-class or non sim-class amp, because there is not a simul class switch on the rear and there are 4 switches on the front panel inlcuding full pwr - 1/2 pwr switch. Although there is a sticker saying "Simul-class power" on the rear side, I was still unsure. Thanks to this board I finally assured myself, that it IS a Simul class amp - I found this written on the output transformer - thank to you guys!

:?: Does anybody know, if the full pwr - 1/2 pwr switch has the same function as the sim class/class A switch used on other Mark III's?
I bought the amp with two pairs of JJ 6L6's - I wanna try to exchange the outer pair by EL 34's - is there anything I should be worried about, or I can just simply pull out the 6L6's and put in the EL 34's?
And last question - is it possible to find out the year of amp production by it's serial number? (SN#24375)

Thank you,

Erik

 

[triodal]

Some of those early Black Dots came with the big 105 power tranformer.
Let us know.

Hey Boogiebabies,how do i know if the amp has that 105 transformer?

 

[Elpelotero]

look for a "105" on the power transformer number, which will be the big black squarish thing on the left if you look at the amp from the back.

 

[triodal]

so what if the mk3 happen to have that transformer?more like a iic+ sound?

 

[Elpelotero]

well....depends what sound you're after. typically people like a C+ with the 105 because it sags less and creates that classic tight thrashy metallica sound. this, IMO, is the sound the C+ is famous for. However, if you like your vintage sound a little more and appreciate Class A, you may be more interested in the smaller transformers because they sag some and are a bit "smoother" or "squishy." the 105 can do these sounds as well tho, and the smaller transformers can do the tight sounds also. the differences are there though for those who want to exploit them.

 

[LUCRETIA]

The Mk3 that i got is indeed 105 transformer.

 

[Wico]

Does anybody know, if the full pwr - 1/2 pwr switch on my Mark III long chasis head has the same meaning (function) as the sim class - class A switch used on other Mark III's?

Can I change the outer pair 6L6's for EL 34's without no worry?

Is it possible to find out the exact year of amp production by it's serial number? (SN#24375)

 

[Boogiebabies]

 

[Scott K]

Some MK III long chassis did not come a simul class sticker and had a half
power switch on the front. To really know you need to look at the part number on the output tranfsformer. It should be SC152019B or 562300.
If not, it's a 60/100 non simul.

The one I've been looking at has the number:

562003

and EIA606-845
Was yours a typo, or is this a different OT?

 

[pmb]

I'm not sure about my mark III. It does have a sticker on it with simul class. But there isn't a switch with something about simul-class. I do have a half-power switch. It's a blue stripe version with six power tubes.
Is it simul-class and does someone know if it's the type of amps called the colliseum amps??
Thanks in advance dudes

 

[Boogiebabies]