Speaker ohm and cab wiring questions

[EAdanikDG]

Hi, just a couple of questions. When wiring two cabs to one head, do you need to use a stereo cable (two jacks on one end, one on the other?) Also do amp companies specially design speakers for individual cabs as two cabs from the same company can be a 4X10 with 8 ohm impedence and a 2X10 with 8 ohm inpedence. Would 3 speaker cabs have a decimal number impedence? Thanks

[SurferJoe46]

Most (not all?) heads have twin outputs - or most that I have seen anyway.

If so, use two separate cables and NOT stereo cables as you might be upsetting the ground on a stereo cable and carrying both grounds back on one cable - and that's just wrong.

Then again, many cabinets also have dual INPUT jacks and you can just daisy-chain cabs that way with a cable between them and the back of the amp feeding one of the cabs at the same time.

Pay strict attention to the load capacity of the amplifier though and never drop below it's rated Ohms or things will go rapidly, if not instantly, downhill.

Ohms are odd to figure for a n00b.

8 + 8 = 4 (see?)
4 + 4 = 2

[Jaco who?]

Originally Posted by EAdanikDG

Hi, just a couple of questions. When wiring two cabs to one head, do you need to use a stereo cable (two jacks on one end, one on the other?) Also do amp companies specially design speakers for individual cabs as two cabs from the same company can be a 4X10 with 8 ohm impedence and a 2X10 with 8 ohm inpedence. Would 3 speaker cabs have a decimal number impedence? Thanks

You either run both cables from two outputs from the head, or if there is only one, you daisy chain the second from the first cab to the other. The impedance is the same either way.

4x10 cabs usually have each pair of speakers wired in series, and then those two pairs are in parallel. A 4Ω version would have 4Ω speakers, and a 8Ω version would have 8Ω speakers.
OR, the 4Ω might have 16Ω speakers all in parallel.


2x10 cabs are usually parallel, so a 4Ω version would have two 8Ω speakers and an 8Ω version would have two 16Ω speakers.

Three speaker cabs are often 5.3Ω, like the Epifani UL310 with three 16Ω speakers in parallel.

http://colomar.com/Shavano/4x12wiring.html Poke around there, there are other examples too.

[EAdanikDG]

Originally Posted by Jaco who?

You either run both cables from two outputs from the head, or if there is only one, you daisy chain the second from the first cab to the other. The impedance is the same either way.

4x10 cabs usually have each pair of speakers wired in series, and then those two pairs are in parallel. A 4Ω version would have 4Ω speakers, and a 8Ω version would have 8Ω speakers.
OR, the 4Ω might have 16Ω speakers all in parallel.


2x10 cabs are usually parallel, so a 4Ω version would have two 8Ω speakers and an 8Ω version would have two 16Ω speakers.

Three speaker cabs are often 5.3Ω, like the Epifani UL310 with three 16Ω speakers in parallel.

http://colomar.com/Shavano/4x12wiring.html Poke around there, there are other examples too.

Thanks, this helped a lot