Cab question….

[JackBootedThug]

So I got this old USA crate cab but it has a 4 ohm tap. My other cabs are all 8 ohms I believe. One might be 16. I’m not really going to be able to run this with another cab am I? My single has an 8 and two 4 ohm taps but my 6505+ combo has a switch for ohms… while it can drive it by itself it probably will explode and burn my house down if I try and run another cab right? Don’t cross the flow or mismatch ohms right?

 

[311boogieman]

I was wanting to say yes, your boogie can handle the mismatch but I don't want to be that guy. After reading these two (quick read) descriptions I would say don't do it. Running both of those amps into an ABY and separate cabs would be far more enjoyable anyway

good start

diagrams

 

[shar-vell Dan]

4 ohm cab ain't much to work with.

 

[BeZo]

Guitar heads don't go past 4 ohms, so there isn't a safe mismatch with that cab. You could possibly rewire it to 16 ohms depending on what speakers are in there. If all the speakers are 16 ohms and wired in parallel to make a 4 ohm load, just rewire the cab to be 16 ohms.

 

[Rackman]

The only reasonably way you could use that with another cab would be to get another 4ohm cab, make or buy (where?) a custom serial speaker cable, connect the two cabs in serial (8 ohms) and use the 8ohm tap on an amp.

Doable, but probably not worth it.

 

[OldGtrGuy]

My suggestion is to check the speaker ohms. May be possible to rewire the 4ohm cab to 8ohms.

Then run both 8ohm cabs with your 4ohm tap if your amp has one.

Edit: looks like Bezo already said the same thing.

 

[BeZo]

The only reasonably way you could use that with another cab would be to get another 4ohm cab, make or buy (where?) a custom serial speaker cable, connect the two cabs in serial (8 ohms) and use the 8ohm tap on an amp.

Doable, but probably not worth it.

My buddy made one of those. Nobody in their right mind would ever sell you one because if you use it wrong you can blow shit up.

...let's just take that option of the table here.

 

[Rackman]

My suggestion is to check the speaker ohms. May be possible to rewire the 4ohm cab to 8ohms.

Then run both 8ohm cabs with your 4ohm tap if your amp has one.

Edit: looks like Bezo already said the same thing.

If it could be rewired (and it almost certainly can be) it would end up at 16 ohms because you would either be moving 4x 16-ohm speakers from parallel to series/parallel or 4x 4-ohm speakers from series/parallel to series.

So that is an option.

 

[Rackman]

My buddy made one of those. Nobody in their right mind would ever sell you one because if you use it wrong you can blow shit up.

...let's just take that option of the table here.

I mean it's in the category of things that won't work if you don't understand them, but in terms of OT damage risk it's no worse than the risk of just forgetting to connect a speaker.

 

[BeZo]

I mean it's in the category of things that won't work if you don't understand them, but in terms of OT damage risk it's no worse than the risk of just forgetting to connect a speaker.

Oh yeah. It's a really simple circuit. Anyone can build it. But the risks aren't really worth the reward though. If you use quality jacks, like Switchcraft jacks, you have to worry about the jacks grounding to the chassis. So, a durable metal chassis and quality components need to be insulated from each other. We used rubber grommets and painted the thing (inside and out) in rubberized undercoating for good measure.

Other alternatives would be to use plastic jacks that don't ground to the chassis, or an enclosure made of plastic or wood. Even if you made a good wood enclosure with quality metal parts, it still fails if it's used incorrectly.

 

[shar-vell Dan]

Guitar heads don't go past 4 ohms, so there isn't a safe mismatch with that cab. You could possibly rewire it to 16 ohms depending on what speakers are in there. If all the speakers are 16 ohms and wired in parallel to make a 4 ohm load, just rewire the cab to be 16 ohms.

Some 60's Fender amps / cabs were 2 ohms. MESA transformers are spec'd for certian mismatches. Most every amp does not do well with mismatches.
Including solid state amps.

 

[7704A]

You can with a weber z-matcher.

 

[JackBootedThug]

Honestly I heard that the cabs are solid but shit speakers. So definitely will keep and replace with a quad of something eventually. For a 45 yo cab it’s in great shape….

 

[JackBootedThug]

I will try it on its own here sometime soon

 

[ZEEGLER]

I would just rewire it to 16 ohms. It's unlikely that it has 4 ohm speakers, so They are almost certainly 16 ohm speakers, which means you can re-wire it in series/parallel to 16 ohms.

EDIT: Holy shit! 80 watts max for a 4X12? 20 watt speakers? Yeah, they are probably shit.

 

[MadAsAHatter]

3 options off the top of my head:

1: Get a Weber Z-matcher or something similar that can match amp/cab ohms.
2. Rewire it to be 16 ohms.
3. Rewire it to be a dedicated stereo or wet/dry cab at 8 ohms per side.

 

[Rackman]

Oh yeah. It's a really simple circuit. Anyone can build it. But the risks aren't really worth the reward though. If you use quality jacks, like Switchcraft jacks, you have to worry about the jacks grounding to the chassis. So, a durable metal chassis and quality components need to be insulated from each other. We used rubber grommets and painted the thing (inside and out) in rubberized undercoating for good measure.

Other alternatives would be to use plastic jacks that don't ground to the chassis, or an enclosure made of plastic or wood. Even if you made a good wood enclosure with quality metal parts, it still fails if it's used incorrectly.

I was thinking build it as a Y-cable. Keep the plugs physically apart.

Not suggesting doing it for a Crate cab, just that it's a 3x plug, 20ft of lamp cord, heat shrink and a few minutes kind of project.

 

[Rackman]

1: Get a Weber Z-matcher or something similar that can match amp/cab ohms.

Yeah when we run into these oddities in the studio we have an Ironman II that does OK. I go back and forth to what degree it's audible, but we've gotten acceptable results.

 

[IHateRap]

I would just look for a good 8 or 16 ohm IR.

 

[JackBootedThug]

What speakers should I get? I have two cabs with v30’s and one with 75’s.