Wiring Cabs, Speaker OHMS all in one thread(possible sticky)

[JakeM]

let us know how you get on and don't be afraid to throw up a diagram or some pics up aswell if you do

jake

[SludgeBurns]

So I have two 2x12's and both are 8 ohm cabs. Both also have two jacks, for daisy chaining I guess. When I use the 8 ohm speaker out on my amp and connect to one of the 2x12's, is it safe to use the other jack on that cab and connect to my other 2x12 or does the load change by doing that?

Both cabs are wired parallel.

[JakeM]

Sludge, that extra jack I assume is for a stereo setup ,ie.if you were using a stereo power amp and wanted to pan left and right. What cab have you got? I may be able to take a look. Does your amp have 2 8ohm outs? if so, I'd run one out to one jack of cab A and the other out the one jack of cab B.

I couldn't tell you for sure without knowing what you have or looking into that particular model.

[SludgeBurns]

One is a Lopo Line cab and one is a Tech 21 cab. They are wired like Dave's Avatar cabs. Here is what he says in his FAQ section:

There are two jacks on the back of the guitar cab. Which do I plug into? On standard mono cabs, the two jacks are tied together in parallel so you can plug into either one and the other would be used as an 'out' to go out and daisy chain to another speaker cab. On a custom stereo cab, the two jacks would be wired both as 'ins' but the majority of cabs are mono.

I guess I'm not sure what that means in regards to the load.

[Big John]

Originally Posted by >Photi G<

For all those man-enough to handle it...

Same goes for this....

[JakeM]

Well in that case Sludge, your golden. The jack will run as an out but I'm not sure if it will change the impedance

[PapaSquash]

Sludge

If the jacks are wired parallel, then the load will be cut in half for a total load of 4ohms (just like two 8ohm speakers wired in parallel would be)


Viva

I'll wire my cabs like this:



http://colomar.com/Shavano/2x12wiring.html

[JakeM]

Papa, that looks fine, call me old fashioned but I just prefer one jack on the back with one choice in ohms. Most amps these days will accommodate for 16ohms or 8ohms

jake

[Grand Pappy]

Great thread. The Boogie Manual tells me it's okay to plug the 16 ohm cab into the 8 ohm jack, but doesn't talk about mixing ohmage. I guess I'll just have to use the 16 ohm cab by it self.
I do have a 1X12 cab loaded w/an 8 ohm EV Force, so I'll be able to use that as an extension cab w/ my 5:25.

[>Photi G<]

Originally Posted by Grand Pappy

Great thread. The Boogie Manual tells me it's okay to plug the 16 ohm cab into the 8 ohm jack, but doesn't talk about mixing ohmage. I guess I'll just have to use the 16 ohm cab by it self.
I do have a 1X12 cab loaded w/an 8 ohm EV Force, so I'll be able to use that as an extension cab w/ my 5:25.

Is your G10 in your Express the 8Ω or 16Ω version, Grand Pappy? If it's the 8, you can plug both it and the EV extension cab into two 4Ω jacks on your amp.

[PunkerJon]

Sweet scored a pair of "cosmetic defect" Black Shadows today for $75 each! Gonna wire that 2x12 expansion for the Rockverb tonight... unless I drink more beer... then tomorrow...

[deepblue]

I think my RV50 may even have 120watt setup... I'll call Orange again and ask them.

Yes, the Orange is 120w's

[Dwin]

I read this all, and I'm still confused.
If I have a 212, and I want it at 8Ω how should I wire the speakers? I want both in and out, so I can daisy chain other cabinets together.

[JakeM]

Originally Posted by Dwin

I read this all, and I'm still confused.
If I have a 212, and I want it at 8Ω how should I wire the speakers? I want both in and out, so I can daisy chain other cabinets together.

I'm not sure about the out, but if you daisy chain an "out" with another identical 212 cab of the same impedance it will half. Does your amp handle 4/8/16?

the in and out is how Sourmash I believe wire their cabs.
To get 8 ohms however you will need 2 16ohms wired in parallel

[LesPauI+SG=Win]

If I were to run 2 4x12 8ohm cabs, would I put my amp on the 4ohm selection?

[JakeM]

not if the amp allows for 2 8 ohm outs, then you will be fine

[Dwin]

Well Its a lopo 212, and it has ins and outs, and is pre wired, my amp has 2 4Ω and 1 8Ω right now the cab has 1 speaker in it, so im using the 8Ω output.

Which Ω speakers should I order? I'm ordering veteran 30's from wcg, should I get 2 8Ω or 2 16 Ω?

[JakeM]

8 ohms and wire them series parallel

[kam4ff]

I want to make a 212 with two 8 ohm speakers at 75 a piece that makes 150 watts. can someone make a wiring diagram so that I can make it at preferably 8 ohms for use with a Marshall head? Also in PapaSquash's post why is there an in and an out on a speaker cab? Do I have to use both?

[JakeM]

Hey KAM, there is a wiring diagram on the first page that allows you to wire your 212 to 8ohms by using 2 8ohm speakers, but ill do a simpler diagram now

jake

[JakeM]

actually Kam, the in out allows you to daisychain cabs but you don't really need that, unfortunately Photobucket are updating their site so my pics on the first page won't work and I won't be able to upload a new one for a while but PM your email and ill send you the diagram

jake

[GitFiddle]

Originally Posted by kam4ff

I want to make a 212 with two 8 ohm speakers at 75 a piece that makes 150 watts. can someone make a wiring diagram so that I can make it at preferably 8 ohms for use with a Marshall head? Also in PapaSquash's post why is there an in and an out on a speaker cab? Do I have to use both?

If you put two 75 watt speakers in your cab it will be a 75 watt cab.
If you put four 75 watt speakers in a cab it will be a 75 watt cab.
If you put two 30 watt speakers and two 75 watt speakers in a cab it will be a 30 watt cab.

[>Photi G<]

Originally Posted by GitFiddle

If you put two 75 watt speakers in your cab it will be a 75 watt cab.
If you put four 75 watt speakers in a cab it will be a 75 watt cab.
If you put two 30 watt speakers and two 75 watt speakers in a cab it will be a 30 watt cab.

No. From my experience, you take the lowest wattage speaker's power handling, and multiply it by the total number of speakers, or

4x75W= 300W

2x75W= 150W

2x30W+2x75= 120W

Total handling will vary ± 20W.

[PapaSquash]

Originally Posted by kam4ff

I want to make a 212 with two 8 ohm speakers at 75 a piece that makes 150 watts. can someone make a wiring diagram so that I can make it at preferably 8 ohms for use with a Marshall head? Also in PapaSquash's post why is there an in and an out on a speaker cab? Do I have to use both?

You can't make 2 8ohm speakers, into an 8ohm cab. your wiring options are series for 16ohms, or parallel for 4 ohms.


You don't need to use both jacks. In fact "input" and "output" are misleading, and for that I apologize. Better labels would be "amp" and "ext" for an extension cab.

The only output of a cab is the noise out the front, the cable completes a circuit that makes that happen (the juice goes into the cab and back out through the same cable) so when I said "output" I wasn't really being helpful.

[BillB1960]

Originally Posted by viva_la_punk

Hey KAM, there is a wiring diagram on the first page that allows you to wire your 212 to 8ohms by using 2 8ohm speakers, but ill do a simpler diagram now

jake

Can't be done. Two 8 ohm speakers will either give you a 16 ohm cab or a 4 ohm cab depending on whether they're wired in series or parallel. With a $1.29 DPDT switch from Radio Shack you can make a cab that you can switch between 4 ohms and 16 ohms but you can't make it 8 ohms.

[BillB1960]

Originally Posted by >Photi G<

No. From my experience, you take the lowest wattage speaker's power handling, and multiply it by the total number of speakers, or

4x75W= 300W

2x75W= 150W

2x30W+2x75= 120W

Total handling will vary ± 20W.

Yup...what he said!

[Mookakian]

I've been thinking...Can a 2x12 bass cab with something like a Mesa Rec 2x12 cab be connected to a 100W guitar tube amp providing watt's an ohm's suit? I lnow how silly this may sound, just not too sure how safe it is on the head or cab

[Dwin]

So, I have a lopo 212, and it has 2 jacks. I believe both speakers are wired in a parallel, its prewired all I had to do was plug my speakers in. Can one jack act to daisy-chain to another cab? Or is it to run the cab in stereo?

[PapaSquash]

Originally Posted by Dwin

So, I have a lopo 212, and it has 2 jacks. I believe both speakers are wired in a parallel, its prewired all I had to do was plug my speakers in. Can one jack act to daisy-chain to another cab? Or is it to run the cab in stereo?

The jack is for adding another cab. I don't like to say "daisy chaining" that seems to imply that the cabs are in series. Cabs connected this way are not like links in a chain, one after another, they are like spokes on a wheel, each connected to the center (your amp's output transformer)

If it were for stereo there'd have to be some sort of switch to separate the speakers when in stereo mode.

It will cut your overall resistance in half (if the added cab is the same as your Lopo. If not, come back with the numbers and we'll talk) Make sure your amp can deal with this.

For this discussion, It doesn't matter how the speakers inside are wired, the Lopo 212, as a unit, has X resistance (ohms) and by adding another path for the signal to travel through you will have lowered that resistance. The signal at that extension jack actually bypasses the Lopo and doesn't pass through it's speakers.

I've never seen a "ext" jack in series, but I haven't seen everything. (and I think you'd have to have some kind of switch for that also, or the jack would cause an open circuit)

[BillB1960]

Originally Posted by Mookakian

I've been thinking...Can a 2x12 bass cab with something like a Mesa Rec 2x12 cab be connected to a 100W guitar tube amp providing watt's an ohm's suit? I lnow how silly this may sound, just not too sure how safe it is on the head or cab

Assuming ohms match I see no reason it wouldn't work. Wattage is immaterial unless you're seriously exceeding the speakers wattage but I'd think with a bass cab that'd be awful hard to do with a guitar amp.