Doubt about the 4, 8 ohns connection to my 4x12 8,16ohns Cab

[Metallicaseeker]

Hello. I'll will buy tomorrou a 4x12 Cab that has two options : 8ohns in stereo mode or 16 ohns in mono mode:

We know that in the back of our Mark V, we have 2 outputs of 4ohns and 2x 8ohns ...


1) What is the difference between the two 4 ohns outputs of my amp, if it exists ?
2) What is the difference between the two 8 ohns outputs of my amp, if it exists ?
3) Can i plug my amp anyway to the 16 ohns Cab mode ? How can i do that if i do not have a 16 ohns output ?
4) Wicth would be the better wiring to me, the better way to connect the amp to my cab , to get a punchier and chunkier sound of my rig ?

PS : I know that it's not a Mesa Cab, sorry about taht, here in Brazil mesa cabs are very rare, but i tested it using the 8ohns output and it sound wonderfull, but i think that i can get more of it...i have 2 eminence the governor here to trade in to bugera speaker, and i'm planing buy other two the governor or v30 to make it better soon...

Thank you all for the answer, you have help me a lot since i bougth my Mark V!

Pedro.

 

[screamingdaisy]

1) What is the difference between the two 4 ohns outputs of my amp, if it exists ?
They're identical. The reason they have two outputs is so that you can plug into two cabs if you run a fullstack.

2) What is the difference between the two 8 ohns outputs of my amp, if it exists ?
Same as #1.

3) Can i plug my amp anyway to the 16 ohns Cab mode ? How can i do that if i do not have a 16 ohns output ?
Plug a 16ohm cab into the 8ohm jack. It won't hurt anything. Your amp will run slightly cooler and sound a little darker than an 8ohm cab, but other than that it won't hurt anything.

4) Wicth would be the better wiring to me, the better way to connect the amp to my cab , to get a punchier and chunkier sound of my rig ?
8ohm cab into the 8ohm jack.

 

[Metallicaseeker]

1) What is the difference between the two 4 ohns outputs of my amp, if it exists ?
They're identical. The reason they have two outputs is so that you can plug into two cabs if you run a fullstack.

2) What is the difference between the two 8 ohns outputs of my amp, if it exists ?
Same as #1.

3) Can i plug my amp anyway to the 16 ohns Cab mode ? How can i do that if i do not have a 16 ohns output ?
Plug a 16ohm cab into the 8ohm jack. It won't hurt anything. Your amp will run slightly cooler and sound a little darker than an 8ohm cab, but other than that it won't hurt anything.

4) Wicth would be the better wiring to me, the better way to connect the amp to my cab , to get a punchier and chunkier sound of my rig ?
8ohm cab into the 8ohm jack.

If i choose 8 ohms on the cab, it means that it's on stereo mode...so do i have to plug two cables to my amp like :
Amp 8 ohms output nº1 ---------- Left Cab conector
Amp 8 ohms output nº2 ---------- Right Cab conector

or just One cable ? My doubt is that 8 ohms is stereo, i do not know how to plug is estereo...

 

[LPJunky]

If i choose 8 ohms on the cab, it means that it's on stereo mode...so do i have to plug two cables to my amp like :
Amp 8 ohms output nº1 ---------- Left Cab conector
Amp 8 ohms output nº2 ---------- Right Cab conector

or just One cable ? My doubt is that 8 ohms is stereo, i do not know how to plug is estereo...

This is incorrect!! Do not do this because you have now a 4 ohms load connected to the 8 ohms OT tap! You will fry the OT if you push your amp!!!

The connectors on the back of the amp are in parallel! You connect a single 8 ohms in one outputs or you connect 2 16 ohms speakers (1 in each 8 ohms) to get a overall 8 ohms load to get a perfect match.

In your specific case your cab in stereo should be connected with two wires (Speaker wires only) to both of the 4 ohms outputs.

If you need more convicing have a look at the MkV schematic.

Happy rocking

 

[Metallicaseeker]

If i choose 8 ohms on the cab, it means that it's on stereo mode...so do i have to plug two cables to my amp like :
Amp 8 ohms output nº1 ---------- Left Cab conector
Amp 8 ohms output nº2 ---------- Right Cab conector

or just One cable ? My doubt is that 8 ohms is stereo, i do not know how to plug is estereo...

This is incorrect!! Do not do this because you have now a 4 ohms load connected to the 8 ohms OT tap! You will fry the OT if you push your amp!!!

The connectors on the back of the amp are in parallel! You connect a single 8 ohms in one outputs or you connect 2 16 ohms speakers (1 in each 8 ohms) to get a overall 8 ohms load to get a perfect match.

In your specific case your cab in stereo should be connected with two wires (Speaker wires only) to both of the 4 ohms outputs.

If you need more convicing have a look at the MkV schematic.

Happy rocking

So the correct mode is :

Stereo Mode 8 Ohms : Run two speaker cables out of the four ohm outputs into the eight ohm inputs on the cab.

Mono Mode 16 Ohms : Plug one 8 ohms jack of the amp to the imput 16ohms of the cab ? Or my amp did not allow a 16 ohms connetion to any cab ?

Thanks!

 

[LPJunky]

So the correct mode is :

Stereo Mode 8 Ohms : Run two speaker cables out of the four ohm outputs into the eight ohm inputs on the cab.

Mono Mode 16 Ohms : Plug one 8 ohms jack of the amp to the imput 16ohms of the cab ? Or my amp did not allow a 16 ohms connetion to any cab ?

Thanks!

Yes that's it. The MarkV is capable of handling a higher load than what the output is labeled for. The manual discuss all kind of situation like that they call them "SAFE MISMATCH". So you could connect your cab in MONO 16 ohms in the 8 ohms output or even the 4 ohms without any harm. I think it would sound a slightly louder in the 8ohms than the 4 ohms. Reasoning here is that the 4 ohms output has more internal resistance that the 8 ohms so the overall load (internal+speakers) respect limits dictated by the out put tranny. But I could be off the mark on the last ramblings ....

 

[HeadlessAxeman]

Dude...Pedro..

just grab the Mesa Boogie Mark V Manual man...its even available on their website...the last section in the manual has all the pictures and the correct/tolerable/incorrect ways of connecting diff speaker cabs across different impedances.(8/4 ohm)

You'll see what connections are correct and what won't work for you

 

[>Photi G<]

You are NOT using a Pukera cabinet with a Mark V. No Way. Like another forum member said, It's like putting Ketchup on a Kobe Meat Steak. You're mixing top-of-the-line equipment with the worst piece of **** China can offer up. I can understand maybe if you are on an extremely tight budget, and need the horesepower, but if you can afford an even marginally better cab, I say, make the switch. Chances are, you aren't playing an outdoor arena, so you won't need the 412 anyways. :roll:

 

[LPJunky]

The manual is good except that it never quite clarify how those outputs are connected to the output transformer. The little diagrams show a generic amp with a number of outputs never the exact layout of the Mark V. Just remember that the 8ohms output has 2 connectors attached to it in parallel (so you can't connect two 8ohms cabs with two cables). Same comment for the 4ohms output (so you can't connect two 4ohms cabs with two cables).

As a final side note. The manual does not show an example where a 4ohms cab is connected to a 4 ohms output AND an 8ohms cab connected to an 8ohms output. One would think it looks like a perfect match. According to a response I received from Mesa a few month ago it is not supported. Only the cases described in the manual are allowed!