Cab re-Wire - 8ohm to 2ohm

[Franz Jr.]

Fellas,

I have a 4x12 bass cab that is 8ohms. I have confirmed it could be re-wired to a 2ohm cab. How would I got about this? Could someone point me in the right direction? Any help is appreciated!!

[Tracebassplayer]

What is the Minimum Load Rating of your amp. most are 4 ohm some are 2 ohms. If you go lower than your amp's MLR it will be come unstable and damage WILL happen.
If you rewire to 2 ohm you will not be able to add another cab.
Look at the VC on the speakers, what is the impedance?

[steveksux]

Depending on how its wired currently and the ohms rating of the speakers you can go from 8 to 2 ohms.

Say if you have 4 8 ohm speakers, 2 in series, the other two in series, and those pairs in parallel with each other.

Like this currently:
+
|---O----O---| -
|---O----O---|

Then just hook all 4 in parallel

+
|---O---| -
|---O---|
|---O---|
|---O---|

Randy

[Downunderwonder]

+1

Depends on the driver impedance. Most likey they are 8 ohm and not 32 ohm. If they are 32 then you're stuck with 8 ohm.

If they are 8 ohm then you put all the + and all the - to the respective terminal at the input, 2 ohm badboy, job done.

Right now they will be parallelled pairs of series or a series of pairs of parallel, so you'll have a bit of rewiring to do.

[steveksux]

The important question is what is your amplifier? Can it support a 2 ohm load.

You definitely won't be able to add a second cab unless you have an amp that supports parallel mono operation, NOT bridge mode. No bridged amp I have ever seen supports a 2 ohm load, only 4. There aren't very many amps that support parallel mono either.

Randy

[Jim Campbell]

Originally Posted by Franz Jr.

Fellas,

I have a 4x12 bass cab that is 8ohms. I have confirmed it could be re-wired to a 2ohm cab. How would I got about this? Could someone point me in the right direction? Any help is appreciated!!

i'm not sure the re-wire will buy you anything.......much more would be gained with another identical cab,methinks

[iiipopes]

+1 to all the above. You're flirting with disaster, since most heads are made to drive 4 ohm loads. Even the venerable SVT runs a 2-ohm load by having two of the 8 X 10" cabs. Please follow the above advice and simply get another cab.

[Tracebassplayer]

Originally Posted by Jim Campbell

i'm not sure the re-wire will buy you anything.......much more would be gained with another identical cab,methinks

+1 more speakers

[Franz Jr.]

Originally Posted by steveksux

The important question is what is your amplifier? Can it support a 2 ohm load.

You definitely won't be able to add a second cab unless you have an amp that supports parallel mono operation, NOT bridge mode. No bridged amp I have ever seen supports a 2 ohm load, only 4. There aren't very many amps that support parallel mono either.

Randy

Thanks guys the amp is a Mesa Titan V12. and I will never use another cab, No need for one. The speakers are all 8ohm, so I know the cab can be wired to 2ohms. This is from the builder.

Again, appreciate the advice

Brandon

[Jim Campbell]

Originally Posted by Franz Jr.

Thanks guys the amp is a Mesa Titan V12. and I will never use another cab, No need for one. The speakers are all 8ohm, so I know the cab can be wired to 2ohms. This is from the builder.

Again, appreciate the advice

Brandon

but do you know from said manufacturer that wiring your cab at 2 ohms will buy you any improvement in performance.....and lets assume that it does.....will the time ever come when you need to use a different head,as in a back up,which may not be stable @ 2 ohm....or is this just one of those exercises in doing something just because you can.....iirc just because you can does not always mean you should....

if the goal is more volume,a second identical cab @ 8 ohms will combine with the first for a 4 ohm load and the extra speaker area will yield more volume largely due to the increase in speaker area.........adding more power to the existing cab via less resistance may or may not.....

[billfitzmaurice]

Originally Posted by Franz Jr.

Thanks guys the amp is a Mesa Titan V12. and I will never use another cab, No need for one. The speakers are all 8ohm, so I know the cab can be wired to 2ohms. This is from the builder.

Again, appreciate the advice

Brandon

Find out from the builder what the displacement limited power handling of the cab is. That's not the same as the thermal rating, and it is what limits output. If your amp has enough power to drive the cab to full output at 8 ohms then there's nothing to be gained from rewiring to 2 ohms. Besides, Mesa lists the amp as 650 watts into 8 ohms, 840 watts into 2 ohms, and that is about a 1dB difference, which is inaudible.

[babebambi]

the Titan is 1200 Watts @ 4 Ohms, 840 Watts @ 2 Ohms, 650 Watts @ 8 Ohms

power different between 2 and 8 ohm is too small to have a noticeable effect in volume

[Tracebassplayer]

Originally Posted by babebambi

the Titan is 1200 Watts @ 4 Ohms, 840 Watts @ 2 Ohms, 650 Watts @ 8 Ohms

power different between 2 and 8 ohm is too small to have a noticeable effect in volume

+1
not for the work involved to rewire....
Plus, the closer you get to minimum load, the easier it becomes unstable and damages the output amp section

[BassmanPaul]

Originally Posted by Tracebassplayer

Plus, the closer you get to minimum load, the easier it becomes unstable and damages the output amp section

Errr, No. If an amplifier was designed to be able to handle a 2Ω load then it will be perfectly stable driving that impedance. It's not stability that causes problems when going below the minimum impedance, it's too much current passing through the output devices taking them out of their SOA and destroying them.