Mark IV and Bogner cab Impedance Mismatch

  • Thread starter Thread starter peckhart
  • Start date Start date
peckhart":3mvtw39w said:
SpiderWars":3mvtw39w said:
Generally speaking, running like that should deaden the tone dull the top end. At least that's my experience. So if that's the issue then several paths mentioned above. If it sounds fine then you're good.

FWIW, I'd be more inclined to make the cab 8 ohms. Or...better yet...just get a used Mesa Traditional 4x12 with original 8ohm V30s for like $400 or whatever. With the money you might throw at it...you could just have another cab.
The mesa cab thought has crossed my mind. Problem is finding one local, plus then I have 3 4x12s. Do I really need 3 ?
Dude. Seriously..I can't believe you're even asking this. You have 4 amps..you need 4 cabs at LEAST.
This is Rig Talk after all..go big or go home! :lol: :LOL:

I'm down to 2 amps...yet I have 4 cabs. Different flavors for each..G12Ms, H30s, 65s, and early 75s. All sound killer and different from one another.

Just order a used Mesa from GC.com, buy online and they'll charge you 26 for shipping. True story.
 
Just run both of your 4x12's using the two 4ohm jacks on your IV. That's what I do.
 
Haha...I need to update my sig. Down to two heads and I think I'm going to stay there a while.
I go back and forth with the Mesa and Helios and it seems nuts to have two cabs sitting on our trailer to pull out the match based on the head I decide to use. And most of the places I wouldn't have space for two.
 
If you can't match the ohms, just make sure the cab is higher than the head. Simple.

According to the Mk4 manual...

...Speaker mis-matching is not a cause for great concern - unless the combined load is considerably less than the rated impedance. If, for example, you run two 4 ohm cabinets - each plugged into a 4 ohm jack - the amplifier would “see” 2 ohms as the total load. And while this will not cause immediate damage, it will result in shortened power tube life. Mis-matching on the high side is always preferable, if you have no choice.

In other words, 8/amp -> 16/cab is fine with Mesa.

I ran my '68 Bassman (factory hard-wired to 4 ohms like all 60's Bassman heads are) into an 8 ohm cab for over two decades with zero problems. My opinion...don't worry about it.
 
I ran my MarkIVa through a Friedman 4x12 (greenbacks on top, V30's on bottom) which was 16ohms. Sounded great! No issues. It's a safe mismatch per Mesa.
 
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