Specific question regarding amp/cabs/ohms

[xJBFx]

Hi everybody this is my first post:

So I have a Sovtek Mig100 which has 3 inputs (4 ohms, 4 ohms, 8 ohms). I have been running an 8 ohm Sovtek 4x12 with it and of course hooking it up to the 8 ohm input. So the other day I picked up another 8 ohm Sovtek 4x12 and I'm wondering how to hook it up. I've done some research and frankly am more confused than before. I *think* I can run both cabs by hooking them to the 4 ohm inputs?

Is this correct? Or do I need to wire the speakers together? And what are advantages and drawbacks of either option?

Thanks for reading!

 

[mrkmas]

2 seperate 8 ohm cabinets will be 4 ohms total when they are ran in parallel. You are correct. use the 4ohm speaker outputs on the back of the amp and you should be good to go.

Note: If you decide to use only one cabinet after hooking both of them upto the 4ohm jacks, the amp/cab will be mismatched and you will need to plug the cab back into the 8ohm speaker output on the amp.

 

[xJBFx]

Thank you!

 

[mrkmas]

Thank you!

Not a problem, that is what we are here for. And welcome to the forum!

 

[GtarLover]

The info you have is correct. One 8ohm cab, use 8 ohm output...Two 8 ohm cabs, use 4 ohm outputs.

There is no reason to wire the cabs any differently. No advantage in this case. There may be advantages if you had 16 ohm cabs, but with your set-up, you are golden just the way you have it.

Have fun with your FULL STACK

 

[blackba]

Its interesting that your Mig 100 has 2 4ohm outputs and one 16ohm output. I had a mig 60 about 10 years ago and it had a 4, 8, and 16ohm output. I would have thought they would have kept this consistent over the mig models, but I guess not.

 

[xJBFx]

Its interesting that your Mig 100 has 2 4ohm outputs and one 16ohm output. I had a mig 60 about 10 years ago and it had a 4, 8, and 16ohm output. I would have thought they would have kept this consistent over the mig models, but I guess not.

It's actually two 4s and an 8 but yeah they made them differently, not only from 50/60 to 100s but also some of the 100s have the same inputs as yours did. No idea why but I'm guessing they probably just changed it at one point so models from the same time period have the same inputs even across wattages.

Thanks for the input everybody!

 

[Les Zombie]

i got a question since we are talking ohms and cabs, say i had (2) 1x12 cabs at 16 ohm each and want to run both with a mark v, would i plug them into the 8 ohm outlets.

 

[mrkmas]

i got a question since we are talking ohms and cabs, say i had (2) 1x12 cabs at 16 ohm each and want to run both with a mark v, would i plug them into the 8 ohm outlets.

That would be correct. 2 separate 16 ohm cabinets in parallel would be 8 ohms total. use both the 8 ohm speaker outputs on the back on the mark V and you should be all set.

note: The minute you unplug one cabinet and only have one running you will be at an impedance mismatch.

 

[threadkiller]

Welcome to the best forum on the net.

 

[Les Zombie]

i got a question since we are talking ohms and cabs, say i had (2) 1x12 cabs at 16 ohm each and want to run both with a mark v, would i plug them into the 8 ohm outlets.

That would be correct. 2 separate 16 ohm cabinets in parallel would be 8 ohms total. use both the 8 ohm speaker outputs on the back on the mark V and you should be all set.

note: The minute you unplug one cabinet and only have one running you will be at an impedance mismatch.

thats what i thought, i ran this setup for a show and used my dual rect a couple months back and i used the 8 ohm speaker outs, but then when i got home i was thinking i hope i didnt make a mistake.
i usually i just use a 4x12.

 

[mrkmas]

i got a question since we are talking ohms and cabs, say i had (2) 1x12 cabs at 16 ohm each and want to run both with a mark v, would i plug them into the 8 ohm outlets.

That would be correct. 2 separate 16 ohm cabinets in parallel would be 8 ohms total. use both the 8 ohm speaker outputs on the back on the mark V and you should be all set.

note: The minute you unplug one cabinet and only have one running you will be at an impedance mismatch.

thats what i thought, i ran this setup for a show and used my dual rect a couple months back and i used the 8 ohm speaker outs, but then when i got home i was thinking i hope i didnt make a mistake.
i usually i just use a 4x12.

sure thing man, good to have the peace of mind

 

[Charvel1975]

Got a show coming up this Saturday and me and other guitarist are running full stacks. We're doing a show prep at practice today and my question is I'm going to be using my Marshall 1960 angled cab and he's letting me borrow his Marshall 1960 bottom cab and he said because on both jack plates being switched to Mono that in each cab will use the 4 ohm inputs so on my Mesa Tremoverb head I have 2 4 ohm speaker outs do I just run one speaker cable from each into 4 ohm inputs on the cabs?

 

[cardinal]

Punctuation!

Modern Marshall cabs are either 16 or 4 ohm stereo. If you're running two, set them for 16 ohm and plug each one into an 8 ohm speaker jack.

 

[Charvel1975]

Punctuation!

Modern Marshall cabs are either 16 or 4 ohm stereo. If you're running two, set them for 16 ohm and plug each one into an 8 ohm speaker jack.

Well at practice earlier today I hooked my Mesa Tremoverb head to both Marshall 1960 4x12 cabs (mine is the angled one you see in my Sig) and the other one is a 1960 bottom cab. On both cabs the Mono/Stereo switch was set to Mono and I ran 2 Monster speaker cables: 1 going from 4 ohm speaker out on Mesa to 4 ohm speaker input on Marshall 1960 angled cab and 1 going from 4 ohm speaker out on Mesa to 4 ohm speaker input on Marshall 1960 bottom cab. Was I running it right?

 

[tubortski]

Punctuation!

Modern Marshall cabs are either 16 or 4 ohm stereo. If you're running two, set them for 16 ohm and plug each one into an 8 ohm speaker jack.

I would run it like cardinal explained.

Running both at 4ohms equals a 2 ohm load.

This is from the Tremoverb manual:
SPEAKERS: Two 8, two 4 and one 16 Ohm jack are provided for speaker interfacing. The
TREM-O-VERB
is not very sensitive to
speaker mismatches and will not be damaged by them, except that very low ohmage loads will cause the power tubes to wear faster
.
A single twelve-inch 8 Ohm speaker should generally be connected to the 8 Ohm output. When using two 8 Ohm speakers, connect
them both to the 4 Ohm outputs provided (because the total load is 4 Ohms in that case.) If you have the
TREM-O-VERB
Combo,
your two 16 Ohm speakers are wired in parallel producing an 8 Ohm load

 

[Charvel1975]

Punctuation!

Modern Marshall cabs are either 16 or 4 ohm stereo. If you're running two, set them for 16 ohm and plug each one into an 8 ohm speaker jack.

I would run it like cardinal explained.

Running both at 4ohms equals a 2 ohm load.

This is from the Tremoverb manual:
SPEAKERS: Two 8, two 4 and one 16 Ohm jack are provided for speaker interfacing. The
TREM-O-VERB
is not very sensitive to
speaker mismatches and will not be damaged by them, except that very low ohmage loads will cause the power tubes to wear faster
.
A single twelve-inch 8 Ohm speaker should generally be connected to the 8 Ohm output. When using two 8 Ohm speakers, connect
them both to the 4 Ohm outputs provided (because the total load is 4 Ohms in that case.) If you have the
TREM-O-VERB
Combo,
your two 16 Ohm speakers are wired in parallel producing an 8 Ohm load

So I should've ran 1 speaker cable out of one of the 8 ohm speaker out's on Mesa into the 16 ohm input on Marshall cab and the same for the other Marshall cab?

 

[cardinal]

^ yes. Use two speaker cables. Take one: plug one end into an 8 ohm jack on the head; plug the other end into one of the 1960 cabs set to 16 ohm mono. Do the same for the other cable and cab.

Once you add more than one cab, you can't simply match up the number on the cab with the number on the head. With two cabs of the same impedance, you need to divide that impedance by two to figure out which amp output to use. So two 16 ohm cabs use 8 ohm amp jacks (16/2). Two 8 ohm cabs use 4 ohm amp jacks (8/2). Two 4 ohm cabs need 2 ohm amp jacks (4/2).