If an amp is rated at a minimum of 2 Ohms, is it feasible to hook it up to 1 4 Ohm cab and 1 8 Ohm cab? Is it bad for the amp and/or the cabs. My intuition tells me that 2/3 of the current will go through the lower resistance 4 Ohm cab, so I assume if it's rated to handle 2/3 of the amps output that would be OK. Will the volume of the 8 Ohm cab be totally drowned out by the other and therefore useless?
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resistance question
- Thread starter lomo
- Start date
It will work.
You will have a 2.76 ohm load.
And your right, the 4ohm cab will recieve 2/3rds and the 8ohm cab will recieve 1/3rd.
However, if the cabs are different, you will probably not notice much difference, and will be louder overall
You will have a 2.76 ohm load.
And your right, the 4ohm cab will recieve 2/3rds and the 8ohm cab will recieve 1/3rd.
However, if the cabs are different, you will probably not notice much difference, and will be louder overall
Yep. Plus if one cab is getting double the power of the other (assuming they are equally efficient) it will be 3 dB louder, which is only 23% louder according to Invalid Link Removed
If the 2 outputs are in parallel they would see a 16 Ohm load (8+8) and a 4 Ohm load in parallel, which is a 3.2 Ohm load. The 4 Ohm load would get 4 times the (8+8) Ohm load, so it would be 8 times louder than each 8 Ohm cab.
Unless you are sure it is a stereo amp, no. The outputs are most likely in parallel. What amp is it?
And just to nitpick, the measurements for cabs/speakers are the impedance, not the resistance. Resistance is DC, impedance is AC. That is why an 8 ohm speaker never measures 8 ohms with an ohmmeter.
Oops, I read this wrong. Are you sure you are running the cabs in series? It requires a very special cable. If so, than that is ok as GaryM said.
The situation is an Ampeg PB800 through a pair of Phil Jones 4 B ext cabs. 550 watts into 4 Ohms and 8, 4 inch drivers. The tone and definition are exquisite, but in order to get over a pair of reasonable guitars and a drum kit (at rehaersal in my laundry room , I'm cranking the input control to 9 and the main gain to 7 or 8-even with an active bass. I don't like that. The larger PJ cabs are too heavy. I'm wondering about getting hyper-modular and adding a 2x10 or 4 Ohm 12 or 15 to move the extra air. The sensitivity of the PJ cabs is 95dB. Any suggestions?
, I'm cranking the input control to 9 and the main gain to 7 or 8-even with an active bass. I don't like that. The larger PJ cabs are too heavy. I'm wondering about getting hyper-modular and adding a 2x10 or 4 Ohm 12 or 15 to move the extra air. The sensitivity of the PJ cabs is 95dB. Any suggestions?
