Multiple Amp Splitting

[Bfeeney]

Hi everyone. I have a question about hooking up multiple amp heads. I have a Blackstar HT5 on a 4x12 now but I want to try others like a DIY Mojotone 5E3 kit, a Joyo amp and my work buddy has said he might give me his Vox Night Train. I'm going to get another 4x12, so I'll have two separate 4x12's with two amps per cabinet and a small chain of pedals. My question is, If I'm only going to run one amp at a time, can I make a Y splitter for the speaker cables and a 4 to 1 for my pedal output out of jacks in series? I know it wouldn't work great for running two amps at a time, you need a buffered splitter for that. Would it mess with the signal having three dead-ends in the circuit? My goal is to just plug my guitar in and flip on whatever amp and be at 100%. I have a boatload of jacks so if I can do this free that would be awesome. Thanks everyone

 

[jeremy]

you can run four amps through two 4x12 cabs, assuming you can split each 4x12 (mono/stereo switch), i dont know about the y splitter speaker cable idea. that seems fraught with potential issues. clearly spell out what your plan is

 

[Securb]

Every product I have seen that does this disconnects the signal from the unused amp. It sounds like you will only have one head on at a time, but I would not do a Y cable. One head feeding into another on or off seems like a recipe for disaster. Most of the products designed for this function cost hundreds of dollars. I am in the same boat, and I connect and disconnect heads as I use them.

 

[Mincer]

There is Stompmix 4, and it gets great reviews.

 

[AdrianSD]

If something goes wrong and you end up with the amp running without speaker load, well, that might hurt.

 

[Bfeeney]

Thanks for the replies. I drew a quick picture to show you what I'm thinking. Only one amp will be on at a time with this passive setup

 

[Artie]

You absolutely can not do that. Doesn't matter if the amp is on or off. One will be feeding power into the output transformer of the other amp.

Electrons don't know where they're supposed to go. You must use an A/B switch that's designed for amp power, and the unused amp must be at zero volume. Standby, would even be better.

 

[Securb]

I think the most inexpensive safe way to do this is to put in a stereo/mono switch on the cabs and run each head into 2x12

 

[Artie]

^^^ Yup. That would be a good plan.

 

[Bfeeney]

I think the most inexpensive safe way to do this is to put in a stereo/mono switch on the cabs and run each head into 2x12

So is that basically the same as my idea but with switches in there?

 

[Securb]

So is that basically the same as my idea but with switches in there?

Yes. You are isolating each circuit so the amps are not feeding energy back into each other. Also in this configuration you can run all 4 at the same time or in any combination.

 

[Animal]

Provided you're splitting the guitar signal before it goes to each amp and each amp has their own discrete speaker load, this is absolutely possible. You cannot however just turn each amp off after each amp output, at least without some expensive dummy load gizmo system. Rather you would be silencing the split guitar signal into each amp so they produce no sound whilst still having a speaker load.

The stereo switch as shown above would have the same possibility as having two separate mono speaker cabinets. In your case, two stereo cabs could be used as 4 discrete speaker loads.​

 

[Bfeeney]

I think I'll make up a test rig with switches to isolate things and see how that goes. If it works then I'll redo the test rig to a more final product version, if it doesn't then I already have the JHS buffered a/b/y and buffered splitter bookmarked. Thanks everyone for your help

 

[Artie]

I think I'll make up a test rig with switches to isolate things and see how that goes. If it works then I'll redo the test rig to a more final product version, if it doesn't then I already have the JHS buffered a/b/y and buffered splitter bookmarked. Thanks everyone for your help

This changes everything. Apparently, you have electro-mechanical skills. (You probably own a Dremel tool or two.)

Buying a custom built switcher, like from CAE, (Custom Audio Electronics), could set you back a grand or two. But if you build it yourself, now we're talking a buck or two.

The pic I'm posting is for reference only. Someone, in a vintage audio forum I frequent, wanted a switcher so that they could select between four different stereo amps, and four different stereo speakers. (Using Neutrik stereo connectors, which will work great for a guitar/amp switching system.)

It's a little more simple for guitar, because everything is mono. But it's also a bit more difficult, because you probably want foot switches. Desktop switches, (pic enclosed), will pop out when you push the other. Foot switches won't do that. It can be "wired" in by careful relay switching. It just makes that schematic a bit more tricky.

Gimme a sec. (If you're interested.)

My "sec" is a day or two. Or three.

 

[Artie]

I can't edit that post. It's not too difficult to add load resistors so that an amp won't see "no-load." They don't need to be large, because the unselected amp will be muted. When you build it yourself, the sky's the limit.

 

[Bfeeney]

This changes everything. Apparently, you have electro-mechanical skills. (You probably own a Dremel tool or two.)

I do have an Electro-Mechanical Associates that I don't use much working on engines. When Securb posted about the speaker cabinet switch my mind immediately went to a DPDT type switch. I said in my original post that I would like to just flip an amp on and be good to go, if I have to also push a button it wont kill me. I just don't want to unplug wires to change amps. I think I'm on to something here. Thanks everyone