Merging cabs?

[YnJ]

I have this little gadget I find very useful, the Palmer Cab Merger. You can merge two cabs having the same impedance and plug it into a single output from the amp. I'm just wondering if you can use more than a single cab merger in the same set up? If I have two 2x12s, each rated at 16 ohm, I use the cab merger and plug the cable from the amp into the parallel input on the merger and the 8 ohm output on the amp. Then if I want to use a 4x12 8 ohm cab as well, can I plug the cable from the first merger going to the amp into a second merger together with the 4x12, and plug the cable from the series input into the 16 ohm output on the amp?

Just to take it a step furter, can I use four cabs with three mergers, two cabs each into a merger, and then into a third merger which goes to the amp?

[BertKoor]

Yes. Just follow the diagram on the box.

2x 16 ohm in parallel is 8 ohm indeed.
That in parallel with another 8 ohm cab requires 4 ohm output of the amp. Or put in series it's 16 ohm again.

But you only have two ears

[YnJ]

Thanks! Two ears are a good reason to get the sound in stereo though

Anyway, to put it simple, can an amp run as many speakers as you want without blowing something?

[BertKoor]

I'd rather call that configuration "dual mono".

Matching the impedance is most important - with tube amps.

Power of the amp is sinply distributed, so I don't expect anything blowing up. There's no big warning on the cab merger, right?

[mystran]

Just remember that connecting more cabs like this won't magically give you more power.

The total is what the amp can drive into the combined impedance and it'll just get distributed between the cabs.

[YnJ]

Do you mean I can't take power over Northern Europe with four cabs?

It's not about getting louder, it's about mixing different cabs to get different sounding results. And it's at least a tad stereo when you use different cabs, isn't it? And the most important reason I ask btw, is because I have converted a couple of my cabs to permanent stereo cabs. So if I want to us them as regular 4x12 cabs I have to use the merger, or buy a chassis plate with a switch. The merger is cheaper, and I don't have to worry about forgetting to flick the switch. If I want to use these cabs in a two 4x12 set up I need at least a second merger though

[BertKoor]

I have converted a couple of my cabs to permanent stereo cabs.

Are there separate input jacks for the left & right channel?

If yes, you can probably wire a (switching) connector so you get the same signal to both speakers when only one plug is inserted.



(image from digikey.com)

[YnJ]

Yes, there are separate inputs. They are for all practical purposes two 2x12" in the same cab

I don't want a switch, so I don't have to worry about forgetting to flick it to the right position. I disconnected the switch on the cab which had a switch. I use these cabs primarily when using two ampheads at the same time, so I can connect them to same cab, not the same speakers. Sometimes I want to use them with a single amp though, and sometimes I want to use two cabs with a single amp

[Uncle E]

As long as the combined impedance doesn't go below what your amp's transformer is rated for, you'll be fine.

[zerocrossing]

As long as the combined impedance doesn't go below what your amp's transformer is rated for, you'll be fine.

I can't tell you how many times I've explained to people with blown amps that higher impedance is better for the amp than lower impedance. It's like talking to Nigel about amp volume.

[multree]

And it's at least a tad stereo when you use different cabs, isn't it?

No, it’s not.

The soundstage will be bigger though. Especially when you space both cabs further apart.

For stereo you would need a difference between the left and the right cab, but they’ll get the exact same signal.

[YnJ]

For stereo you would need a difference between the left and the right cab, but they’ll get the exact same signal

Doesn't matter when using different cabs with different speakers, which is what I have to work with anyway. The sound will come out different

[mystran]

For stereo you would need a difference between the left and the right cab, but they’ll get the exact same signal

Doesn't matter when using different cabs with different speakers, which is what I have to work with anyway. The sound will come out different

To get meaningful stereo effect, it isn't really sufficient to just have slightly different frequency response. While this will do "something" in the sense that it'll essentially pan different ranges of frequencies in different ways, sort of like you were using different EQ on different channels, as long as it's static, it'll mostly just sound sort of "off balance." In order to have actually interesting "stereo" effects, you generally need to "uncorrellate" the signals by means of different delays, modulations or some such on each channel.

[YnJ]

Perhaps, I wrote "it's at least a tad stereo when you use different cabs, isn't it?" though, and the definition of mono is the sound mixed in to a single channel, so it's not mono

How meaningful it is in the sense of being stereo is subjective, I would say. You can take a mono track, add stereo effects and call that stereo, so why not two different sounding tracks without effects? When does it become meaningful? Some people just copy and paste the same guitar track, EQ and pan them and call that stereo

[BertKoor]

There's a difference between "stereo" and "double-mono"
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