Help with ohms etc 2

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For reasons which have been explained, you would have to change to 100W, 8 ohm drivers to use your two cabinets plus amp combination in the way that the amp manufacturer intends.

You should NOT buy 4 ohm drivers, they must be 8 ohm.

Two 4 ohm cabs in parallel gives 2 ohm - amp is damaged.
Two 8 ohm cabs in parallel gives 4 ohm - amp is OK.

Wiring two 4 ohm cabs in series is not a good option as it needs non-standard cabling.
 
In any case your current speakers are 40W only each and amp is 150W into 4 ohm, so I suggest 2 solutions.

1) to use today, as is, almost zero expense: build an adapter box, with 3 jacks:

Jack grounds must be insulated from each other so use plastic "Marshall/Cliff type" jacks or mount them in a plastic box or use tape and insulating grommets.

2) buy new speakers but 8 ohm 100W each.
 

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Thanks.
I always carry one of them in my toolbag, useful when people want to connect *all* cabinets available to a single amp and don´t get the "2 ohm load bad, 1 ohm even worse" thing.
I actually have a 1 to 4 adapter (4 series parallel jacks) so up to 4 cabinets can be connected to a single amp output.

Anybody can build these adapters: "any" type jacks in a "sandwich" "Tupperware" box, soldering is minimal, holes can be made with a kitchen knife, cover pressure-fits so no need for bolts or screws , the deluxe version is same wrapped in some packing tape, the super deluxe one uses gaffer tape :)
 
In any case your current speakers are 40W only each and amp is 150W into 4 ohm, so I suggest 2 solutions.

1) to use today, as is, almost zero expense: build an adapter box, with 3 jacks:

Jack grounds must be insulated from each other so use plastic "Marshall/Cliff type" jacks or mount them in a plastic box or use tape and insulating grommets.

2) buy new speakers but 8 ohm 100W each.

THANK YOU FOR THIS INFO.DO YOU HAVE A DRAWING OF YOUR 4 TO ONE JACK BOX ? AND DO I NEED TO USE STEREO JACKS ?
 
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In any case your current speakers are 40W only each and amp is 150W into 4 ohm, so I suggest 2 solutions.

1) to use today, as is, almost zero expense: build an adapter box, with 3 jacks:

Jack grounds must be insulated from each other so use plastic "Marshall/Cliff type" jacks or mount them in a plastic box or use tape and insulating grommets.

2) buy new speakers but 8 ohm 100W each.

THANK YOU FOR THIS INFO.DO YOU HAVE A DRAWING OF YOUR 4 TO ONE JACK BOX ? AND DO I NEED TO USE STEREO JACKS ?
 
Here you have the adapter which lets you connect 1/2/3/4 cabinets safely to a single amplifier/powered mixer output.
Sometimes saves the bacon :) , specially at Charity events, Schools, Churches, where there is zero budget, no $$$ involved, and "good Samaritans" in good faith try to "help" you by connecting any random speaker they can find to your cherished amplifier, overheating/blowing it because of the sub-ohm total impedance achieved.

Only instruction given is: "connect speakers to outputs numbered 1-4 in that order" which should be easy enough to follow ..... I hope.
 

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i like that adapter!
provides easy series or parallel connection for mono plugs
correct me if i'm wrong there's on one condition that would result in "no sound" and that would be if someone loaded just J2 and J4 if that's right i would include it in the * list of conditions.
 
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