Impedence setting for my amp and speakers

[t1r12003]

I have a Peavey solidstate amp head that has two outputs for cabinets on the back. It also has an impedence selector switch for 16, 8, or 4 ohms. I have a 2X12 combo amp that doesn't work, but I can use it as a 2X12 cabinet. The speakers are 12" 8 ohm speakers and I plug each into the 2 outputs of the amp.

This is a quote from the Peavey manaul, "If two enclosures of equal impedance are used, the switch should be set at one half of that value (e.g., for two 16 ohm enclosures, set switch to 8 ohms; for two 8 ohm enclosures, set switch to 4 ohms)."

Does each 12" 8 ohm speaker qualify as an 8 ohm enclosure? Should I set my impedence switch for 4 ohms?

Thanks, I just don't want to ruin the amp head.

 

[metalspider]

Re: Impedence setting for my amp and speakers

yes.

 

[The Golden Boy]

Re: Impedence setting for my amp and speakers

NO!!!!

It depends on how the cabinet is wired.

Two 8 ohm speakers wired in series will be 16 ohms but two 8 ohm speakers wired in paralell will be 4 ohms.

 

[metalspider]

Re: Impedence setting for my amp and speakers

he said he is hooking up each speaker separately into the head,so they are in parallel.so in his case its 8 divide by 2 =4 ohm.

 

[Sludgenutz]

Re: Impedence setting for my amp and speakers

he said he is hooking up each speaker separately into the head,so they are in parallel.so in his case its 8 divide by 2 =4 ohm.

+1. I read it wrong the first two times too.

 

[The Golden Boy]

Re: Impedence setting for my amp and speakers

he said he is hooking up each speaker separately into the head,so they are in parallel.so in his case its 8 divide by 2 =4 ohm.

After reading that over... you're right- I think. I'm sorry!

As long as the user has a cable connecting each speaker individually to each jack. One speaker to one jack, the other speaker to the other jack.

 

[t1r12003]

Re: Impedence setting for my amp and speakers

Thanks guys.

Yes, I have one cable connected directly to each 12" 8 ohm speaker and then plug both into the back of the head, 2 outputs/inputs. I will set my switch to 4 ohms then. I just wondered if even one speaker would be considered an inclosure. I found my answer, no blowing up my amp.

 

[The Golden Boy]

Re: Impedence setting for my amp and speakers

Personally, I'd look at the other ways of wiring it, rather than two cords from two jacks to two speakers in one cab.

For 4 Ohms:

For 16 Ohms:

 

[t1r12003]

Re: Impedence setting for my amp and speakers

Thanks for the suggestion. Can you tell me reasons why you'd do it that way?

Since this is basically a converted 2 X 12 combo amp, that I just unplugged the cables from the combo and plugged right into the amp head, it was way too easy to do it this way.

 

[The Golden Boy]

Re: Impedence setting for my amp and speakers

Thanks for the suggestion. Can you tell me reasons why you'd do it that way?

Since this is basically a converted 2 X 12 combo amp, that I just unplugged the cables from the combo and plugged right into the amp head, it was way too easy to do it this way.

It was hooked up that way in the combo?

Usually combos will have the speakers wired in a configuration and connected to the amp.

IE Fender Twin:

 

[metalspider]

Re: Impedence setting for my amp and speakers

well if the amp has a chorus effect then the speakers would be hooked up separately so they are working in stereo instead of mono(when they are hooked up like you suggested).

 

[The Golden Boy]

Re: Impedence setting for my amp and speakers

well if the amp has a chorus effect then the speakers would be hooked up separately so they are working in stereo instead of mono(when they are hooked up like you suggested).

AH-HA!!!

A stereo combo! I hadn't even thought of that!!

 

[t1r12003]

Re: Impedence setting for my amp and speakers

Yes, it was/is a stereo combo amp with chorus.