Cab Impedence Switchbox

[PaulyWally]

Does anyone make one? Or will I have to make a set of speaker cables myself?

 

If I have three 4 ohm cabs, and my amp is rated at 4 ohms, I can't piggy-back the cabs cause they'll all be in parallel and the combined load will be under 2 ohms. So I'll need to run them in series.

 

 

Edit:

 

Wait a tic... I'm confused.

 

{censored}... what's the equation for this crap again?

 

OK... got it. The original question stands.

[prosigna]

Running the 3-cabinets in series while possible would not be very practical. What type of cabs are they (410, 412, 210, 112, 115.....)? You may need to re-wire each box to be a higher impedance (sometimes you can, sometimes you can't). Then you would run the three boxes parallel to each other (the normal way).

[PaulyWally]

Running the 3-cabinets in series while possible would not be very practical. What type of cabs are they (410, 412, 210, 112, 115.....)? You may need to re-wire each box to be a higher impedance (sometimes you can, sometimes you can't). Then you would run the three boxes parallel to each other (the normal way).

 

While that's a possibility, I don't always want to run the three cabs together. Plus, some amps are good to 4 ohms... others are good to 2. So rewiring the internal speakers my be good in this instance... but it may not be in another.

 

I need an option that is versatile and stupid easy to make series/parallel changes on the fly.

 

If I have to wire up a set of cables... that's fine. I would just rather have a switchbox that can do it for me.

[burdizzos]

So you're fine with running your amp at 12 ohms in order to run all three cabs, but you don't want to rewire the cabs because some amps are "good" to 2 ohms.

 

 

What are the cabs specifically?

[RyCLB]

Maybe this might work:

 

 

https://taweber.powweb.com/store/zmatch.htm

[PaulyWally]

So you're fine with running your amp at 12 ohms in order to run all three cabs, but you don't want to rewire the cabs because some amps are "good" to 2 ohms. What are the cabs specifically?

 

I don't understand what is so hard about the question. Either someone makes a switchbox like I described... or someone doesn't.

 

 

I've already decided all my options, and I have a degree in Electronics Engineering. I'm not stupid... I'm just picky as to how I want things setup.

 

In answer to your question, maybe I don't want to run all 3 cabs. Maybe I want to run 1... or 2. Maybe I'm going to buy a 4th cab that will present more options. Maybe I don't like one of the cabs and trade it in for one that happens to be 8 ohms. Maybe I don't want to use my 4 ohm head. Maybe I want to use my rack with power amp that is good to 2 ohms per channel... or run it bridged where it's only good to 4 ohms.

 

Options man... options. Internally rewiring the cabs is not going to give me quick options on the fly.

 

The bottomline is, I don't want to be confined to which cabs I can run with which amp. I also don't want to be confined to "needing" to purchase an 8 ohm cab cause a 4 ohm will drop the load too much.

 

It's actually quite logical if you think about it.

[PaulyWally]

Maybe this might work: https://taweber.powweb.com/store/zmatch.htm

 

It would if:

 

A) It wasn't so expensive for what I really need.

 

B) It wasn't bound by a power rating.

 

C) I could plug more than one speaker into it.

 

Thanks for the link. I'm gonna ponder that as an option. Just not sure how much mileage I can get from it.

[RyCLB]

It would if: A) It wasn't so expensive for what I really need. B) It wasn't bound by a power rating. C) I could plug more than one speaker into it. Thanks for the link. I'm gonna ponder that as an option. Just not sure how much mileage I can get from it.

Just tryin' to help.

[burdizzos]

No, it make no sense at all, actually.

 

You want to run more cabs, buy a pre/power amp rig with a 2 ohm stereo power amp. Then you can do whatever the hell you want and never have to worry about hurting anything.

 

I don't think anyone makes a swtichbox like you've described, but if you're a Double EE, like you claim, it should take you all of 2 minutes to design one.

 

It could be built in an afternoon.

[Jazz Ad]

It would also be completely useless, except to fry output stages and waste power.

The way cab impedances work is fine and logical. If you want to alter it, you most likely don't understand it too well.

And, uh, degree in Electronic Engineering but you can't remember Ohm's law ?

[PaulyWally]

 

No, it make no sense at all, actually. You want to run more cabs, buy a pre/power amp rig with a 2 ohm stereo power amp. Then you can do whatever the hell you want and never have to worry about hurting anything.

 

 

OK... I'm really not trying to be a dick. But three 4 ohm cabs in parallel is under 2 ohms. So that option is not going to work.

 

And, like I said, I like to have options. Maybe I don't want to bring the rack? Yes, the rack gives me more options... but I don't want to confine myself to just using the rack.

 

 

I don't think anyone makes a swtichbox like you've described, but if you're a Double EE, like you claim, it should take you all of 2 minutes to design one. It could be built in an afternoon.

 

 

Sure. But why should I if I can just go buy one?!? Just about anyone without an EE degree can make speaker cables too. Why don't they?! Cause they're hanging on a convenient shelf that doesn't require 4 trips to 3 stores to get solder, jacks, wire, etc.

 

Yes... I know I'm picky. But this is what I want. And I said I'm not adverse to making something. I would just rather buy the damn thing and be done with it.

[prosigna]

So you need a box you with (4) jacks:

1 - From Amp

2,3,4 - To the speakers

 

When you hook all thos it together you will gey 3-cabs in series with a 12-ohm load. Is that what you are looking for?

 

As far as other option go - can't you do a series/parallel thing and get all three boxes with a single 4-ohm load? I think you get low power rating if you do that. I have never tried series/parallel just seen it in books.

[Rowka]

Since the dual-jacks in just about every cab are wired in parallel, you don't need a box for that. Just daisy them up and you are set.

 

To make a series box would be easy.

Use a regular tip-sleeve jack for the input from the amp.

then run 3 more jacks in series and back to the input. You've got to have all the cabs inserted (or use "shorting" plugs).

Of course, you might want to use switch-jacks for the cab jacks so you can run one, two or three cabs without having to short the empty jacks - but then make DAMN sure you've got at least 1 cab connected or you will short the amp's output and release the magic smoke.

 

19044

[burdizzos]

I've never seen them commercially available or heard of anything like that.

 

Loopmaster could probably build you one, but it will cost you about $120 for a 4 output box with the ability to put the speakers in series. $150 if you want parallel options as well.

 

A 2 ohm stable stero amp could run four 4 ohm cabs, two per side.

[PaulyWally]

It would also be completely useless, except to fry output stages and waste power.

 

Right... that's exactly what I want to do.

 

The way cab impedances work is fine and logical. If you want to alter it, you most likely don't understand it too well.

 

Well... if you think I'm missing something... then please enlighten me.

 

And, uh, degree in Electronic Engineering but you can't remember Ohm's law ?

 

It's been 10 years and I work with computers. I may need to look up equations once in a while... but I remember fundamentals pretty damn well.

[Jazz Ad]

 

OK... I'm really not trying to be a dick. But three 4 ohm cabs in parallel is under 2 ohms. So that option is not going to work.

You're not being a dick. You're just being wrong.

A 2 ohm capable stereo power amp like Burdi proposed would solve your problem just fine. You can plug 1 to 4 cabs without an issue.

[burdizzos]

 

You're not being a dick. You're just being wrong. A 2 ohm capable stereo power amp like Burdi proposed would solve your problem just fine. You can plug 1 to 4 cabs without an issue.

 

 

If Jazz Ad agrees with me, then it is law.

 

:ptu:

 

 

WTF are these new smilies?

[Jazz Ad]

Phil O'Keefe smilies.

Gotta love them. We also get a few other interesting ones.

[PaulyWally]

 

So you need a box you with (4) jacks: As far as other option go - can't you do a series/parallel thing and get all three boxes with a single 4-ohm load? I think you get low power rating if you do that. I have never tried series/parallel just seen it in books.

 

 

2.6 ohms

[Rowka]

I don't like 'em.

 

:pheek: :ptu: :lem:

 

19045

[rikshaw]

:pheek:

[PaulyWally]

You're not being a dick. You're just being wrong. A 2 ohm capable stereo power amp like Burdi proposed would solve your problem just fine. You can plug 1 to 4 cabs without an issue.

 

Right... I do understand that. But I don't want to be confined to a 2 ohm stereo amp for a given setup.

 

Maybe it's my lack of commitment. I dunno... ask my ex-wife. I just want the options, man... I'm all about having options.

 

 

And if that's what I want, and I have my own reasons for wanting that... how can I be wrong?

[burdizzos]

 

I don't like 'em. :pheek: :ptu: :lem: 19045

 

 

Yeah, they suck.

 

:banana4: would be better

[prosigna]

2.6 ohms

 

No, I don't mean 2 boxes in series and the other parallel to them. (2.6 ohms)

 

I mean series/parallel.

 

[Jazz Ad]

Get a tube amp ? No more wondering about cab impedance, just roll the switch.