4 ohm with 8 ohm

[FrankieG44]

We have two passive subs with built in crossovers running at 4 ohms each, we are connecting two mid/tops to them which run at 8 ohms each.
Is there any problem this will cause to the power amp or will the crossover in the subs combat any problems.?

 

[americanaudiophile]

Your amp will have to be stable into 3 ohms to be able to drive this combination in parallel. If the subs have both inputs and outputs then you would need to know if there is some compensation to keep the impedance up built into the high pass output.
If you connect them in series that will give you a 12 ohm load but this will compromise the damping factor of the amp making the bass quality suffer.

 

[rexter]

Are you connecting one 8 ohms speaker to the 4 ohms sub per channel?

Parallel connecting 8 ohms plus one 4 ohms = 2.6 ohms which closer to americanaudiophile estimate. At this low impedance, check if your amp is capable for bridge setup. But this will bring the system to mono.

But if you are connecting Two 8 ohms plus 4 ohms sub then the best way to connect them is series the two 8 ohms together and parallel 4 ohms sub and this will equates to 3.2 which is closer 4 ohms rather than 2.6 ohms if all is parallel. Good thing about it too is you don't need to change anything on the amp.