Question about Cabs with different Ohms on a Mark V

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4406cuda

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I won a couple of auctions for Bogner 1x12 Cube Cabs. They both have vintage 30s in them, but one is a 16 ohm cab and the other is an 8 ohm cab. I haven't received them yet. I have several questions for you all.

Would you guys sell one of them and get another one that matches the other?

If I keep them, should I run them both out of the 8 ohm outs?

Have you guys tried both the 8 and 4 ohm outputs to see if you prefer one over the other? If so, which one do you prefer?
 
If you make them both 16 ohms, you have to run them together all the time (for a total of 8 ohms), but if they're both 8 ohm cabs, you can run one or both. Food for thought.
 
The impedance of a 16-ohm cabinet and an 8-ohm cabinet in parallel is 5.33 ohms.

My guess is you would run those in the 4-ohm jacks.

jbw
 
In the manual it says you can run a 16 ohn cab in the 8 ohm jack and a 8 ohm in the 4 ohm jack for a safe mismatch. I have run it that way. A 16 ohm Orange 2-12 and a open back 8 ohm 1-12. It does sound different running it that way. A little darker a little spongy.

I agree with the above post. Buy one 16 ohm speaker. Daisy chain them for a 8 ohm load.

Nice score on the cabs. Have heard good things on those cabs.
 
Thanks, I will be purchasing a 16 ohm speaker. Any suggestions on the best/cheapest place to get one?
 
4406cuda said:
Thanks, I will be purchasing a 16 ohm speaker. Any suggestions on the best/cheapest place to get one?


www.warehousespeakers.com

Still made in the US of A and a drop in replacements for Celestion's which are now made in China. Half the price too!

Steve
 
steve_k said:
4406cuda said:
Thanks, I will be purchasing a 16 ohm speaker. Any suggestions on the best/cheapest place to get one?


http://www.warehousespeakers.com

Still made in the US of A and a drop in replacements for Celestion's which are now made in China. Half the price too!

Steve

Thanks Steve, I have heard about them on the Triaxis forum.
 
what i don't get is why it's got 2 8 ohm outputs in the first place. if you're plugging in 2 8 ohm cabs the actual, correct connection according to the manual is into the 2 4 ohm jacks, like the mark iv.

why the 2nd 8 ohm output then? one is labelled "combo" so that means you have maybe the combo speaker connected to it at all times, but then when you get another 8 ohm cab connected, you have to switch over to the 4 ohm jacks. i can take a guess about the internal connections to the output transformer, but this setup doesn't make sense to me. do/would you ever connect the 2nd 8 ohm jack to anything with another 8 ohm already connected to the 1st jack? would this be for when you have 2 16 ohm cabs to connect in parallel?
 
Quote:
would this be for when you have 2 16 ohm cabs to connect in parallel?


thats my thought. IMO every amp should have two 16, 8, and 4 ohm jacks.
would this be for when you have 2 16 ohm cabs to connect in parallel?
thats my thought. IMO every amp should have two 16, 8, and 4 ohm jacks.

i would think the real bottlenecks in that respect would be the transformers with all that many taps and the multitude of jacks. sometimes i wonder why mesa doesn't implement an impedance selector switch, but that's just another mechanical boondoggle to break/repair. there is what i would call "more" space than usual on the back panel of the v, but i have not seen inside the chassis, so i don't really think routing another jack for 16 ohm would be feasible (maybe it is, though i don't know how important that really is). ultimately, i think we are fine just living with the (safe) mismatches. if you have a 16 ohm, into an 8 ohm jack will probably the best mesa will ever both to do. not to say it's bad, cause it works fine.
 
i believe, 2 x 16 ohms is used in the 2 8 ohms (cause its 8 total load) one 16 is in 16, 1 - 8 is in 8. 2 x 8s is in both 4s, and 1 four goes to 4.

its more straight forward to have the 2 x16 jacks for 2 x16 ohm cabs but mathmatically and in the circuit it works the way they did it.. i've never seen a 32 ohm cab which would need the 2 - 16 ohm cabs.
 

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