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[rabidgerry]

Hi guy's, I have been thinking about this for a while now due to some amplifiers only have single speaker outputs on the back of them.  I play in stereo so the amps I use will have a left and right.  However some amps will have dual left and right allowing more cabs to be hooked up and of course the load will change and the possibility of more volume becomes available.

Like say if I have an amp that can take 4ohms into one output, and I have 2 x 8ohm cabs, but I can only hook one up at a time there for only giving about half the output of what the amp is capable off, would there be any way that I could couple the cabs?  So they could run parallel into the one output?

I have often wondered if someone ever designed a speaker coupling box for this kind of purpose but I have never come across one.  So I figured if there is no device that does this for you is it possible to fit a cabinet with a coupling input that allowed your cab to have another cab run into it and therefore change the overall?

Anyone any ideas about this feel free to fire them down 

[MarshallJMP]

There are some possibility's ,the easiest way is to add a jack in one of the speakers cabinets so you can daisy chain 2 cabs.Or you can use a small box with 3 jacks,one input and 2 outputs.And last you can add a jack in the power amp if possible.

http://www.youtube.com/watch?v=y_HVgxUAVIU

[rabidgerry]

What is the box option Marshall?  Are these for sale or would it be a device I would have to construct?  Suppose constructing would be easy enough.  Hell it would give me another project (do I have the bloody time though?).

I could even add a series parallel wiring switch hmmmmmm you got me thinking. 

[MarshallJMP]

Well maybe you can buy something like that but you can also DIY,it's quite easy,a box and 3 jacks wired in parallel.

[rabidgerry]

well this is failry easy to make on of these but palmer have already done it

http://www.palmer-germany.com/mi/en/CAB-M-Passive-Cabinet-Merger-PCABM.htm

I'm just going to buy it cause I'm lazy sometimes and it's cheap

[rnolan]

Hey Gerry, this is cabs 101 stuff, you don't need to get fancy. But you do need to stay cognitive of the impedance. If only one jack out on the amp you can (easiest as MJMP says) daisy chain a second box (in parallel or serial depending on desired ohms). another common way is the amp has 2 output jacks wired together in parallel. So 2 x 16ohm speakers (cabs?) in parallel = 8 ohms (nominal) So parallel halves impedance, 2 x 8 ohms  in series = 16 ohms etc.
Parallel: = + <> + and -<>-
Serial = amp +ve > +(sp1) _(sp1) > +(sp2) -(SP2) > amp -ve

[rnolan]

The ADA split stacks have both parallel and series coupling jacks BTW - to get the impedance right

[rabidgerry]

Hey Gerry, this is cabs 101 stuff, you don't need to get fancy. But you do need to stay cognitive of the impedance. If only one jack out on the amp you can (easiest as MJMP says) daisy chain a second box (in parallel or serial depending on desired ohms). another common way is the amp has 2 output jacks wired together in parallel. So 2 x 16ohm speakers (cabs?) in parallel = 8 ohms (nominal) So parallel halves impedance, 2 x 8 ohms  in series = 16 ohms etc.
Parallel: = + <> + and -<>-
Serial = amp +ve > +(sp1) _(sp1) > +(sp2) -(SP2) > amp -ve

hey man, understand all that. The device below does exactly what I want, and this is just for scenarios when I am using cabs that are not my own but I would like to couple them in such a way that I can get their impedance to some up to something compatible with my amps.  The amps I use at the moment only have a left and right speaker output.  The new amp I wish to buy has 2 speaker outs for each side, so this is obviously parallel coupling.

I would have built something similar had I not discovered this

http://www.thomann.de/gb/palmer_cab_m_merger.htm

[rnolan]

I don't know, You can just work out the various impedance of the boxes you get to plug into. They are going to be 8 Ohm cabs typically. If they are less i.e. 4 Ohm cabs you'll get a bit more from the amp, if they are more a bit less (very unusual to have a cab that isn't 4, 8, or 16 Ohm)

[rabidgerry]

I don't know, You can just work out the various impedance of the boxes you get to plug into. They are going to be 8 Ohm cabs typically. If they are less i.e. 4 Ohm cabs you'll get a bit more from the amp, if they are more a bit less (very unusual to have a cab that isn't 4, 8, or 16 Ohm)

I tend to run into cabs at 16ohm or else 4ohm with a 16ohm option also.

The reason this cab coupler box would be handy would be in a scenario where an amp only has 1 speaker output and you have 2 cabs and you want to use both so as you can get the full amount of output.  So an amp runs full power at 4ohm, but you have 2x8ohm cabs.  So that's completely sorted if you have the cab coupler because you stick the cabs into the coupler unit in the parallel inputs and make a load of 4, then run that to the speaker out of the amp and hey presto you have 4 ohm load delivering maximum output from the amp which is always a good thing.

I just remembered I will not need the cab coupler now because them amp I am looking at has 4 speaker outputs!  2 for each side left and right, however when I was looking at a marshall it only had 2 speaker outputs 1 for each side and this would have been an issue with the 4 speaker cabs I use.  I still might pickup one for emergencies.  Good little invention.

[rnolan]

Hey RG, most cabs have an additional parallel jack on the back so you can daisy chain 2 x 8 ohm cabs to get 4. ADA cabs also have a series extension option. If the cabs only have 1 jack, then you need to use the splitter for amp with single jack.

Most solid state amps seem happy with 4, 8 or 16 ohm loads (more impedance = less output). But remember that 16 ohm speakers are typically more efficient/more sensitive (more coils/turns of copper around the voice coil). Tube amps use an output transformer between the amp and cab so you select the correct "tap".

[Dante]

BUMP THE NECRO THREAD:

I have two 1x12 cabs, which is fine for my ADA stuff. However, I sometimes use a H&K head (and sometimes a Peavey) that only has one output. I'll be rewiring one of my cabinets by adding a parallel jack. That way, i'll be able to use both cabs with an 8 ohm load from the two 16 ohm speakers

This seems like a better option than getting a 2x12 cabinet and costs me nothing (I have a jack in my parts bin)

[Systematic Chaos]

You could also get a Palmer Cab M for ~30$. Tiny box and Gadget for exactly the purpose you’re looking for

[Dante]

You could also get a Palmer Cab M for ~30$. Tiny box and Gadget for exactly the purpose you’re looking for

I didn't know somebody made those, but I did have that idea. I even have an old footswitch box for 2-buttons that I could put some jacks into...but then I thought to myself "what about this little box? Where does that go when you have it all plugged in?

It just seems cleaner to install one jack in the back of the cab and not have to carry the little box around.

All I need to do is wire up a couple jumpers and I'm done (pic attached if you don't wanna watch the video):

[Systematic Chaos]

That’s also a neat way to do it, absolutely. My old Boogie 2x12 Halfback cab actually came like this…but with two 8ohm speakers, so 4ohms when going mono. I rewired it to serial when in mono > 16ohms. Safer and more common (even if I use an 8ohm amp out it’s a safe mismatch)