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How To 

How to Bi-Amp Speakers with an external amplifier


Bi-amplifying you speakers will be very helpful when you need to use a really power amplifier for other speakers and sub-woofers. Bi amplifying the speakers involves simple steps of using the RCA splitter to send more than one signal to the speakers. Here is how you can easily Biamp the speakers with an external amplifier.

‘Step 1’
‘Use the RCA splitters for connection’

In order to bi-amplify the speakers, you need the ‘RCA Splitters’ for connection. The RCA splitters will help in sending two signals to each speaker. Make sure any RCA splitter you use have single female and two dual male connectors.


‘Step 2’
Connect the RCA outputs from the AV Receiver’

The first step is to ‘Connect the RCA outputs’ from the AV Receiver. As shown below, the connections are made front left and the front right speakers in the main pre-out section of the AV receiver.


‘Step 3’
‘Connect the two male ends of the splitter’

The next step is to ‘Connect the two male ends of the splitter’ to the ‘first two amplifier inputs’. Make sure to remember which two amplifier inputs you are considering for the left speakers. Similarly notice the ports for the right speakers.


‘Step 4’
‘Connect the second splitter male connector’

Now, ‘Connect the 2nd splitter male connector’ to the 3rd and 4th amplifier inputs which here, is considered as ports for the right speaker. Make sure the wires are plugged in perfectly.


‘Step 5’
‘Connect the speaker wire to the Amplifier’

Now, the next step is very important. ‘Connect the speaker wire to the amplifier’. Make sure to consider the first two outputs for the left speaker and the next two outputs for the right speaker. This must be in sync with the assumption you make in the previous steps.


‘Step 6’
‘Connect the speaker wires to the speaker’

Now, you need to ‘Connect the speaker wires to the speaker’ . Connect one pair of the speaker cable to the low frequency binding posts and connect the other pair of the speaker cables to the high frequency binding posts. Screw the posts to ensure the wires are plugged in perfectly.

‘You can thus easily Bi-amp speakers with an external amplifier by following a series of steps mentioned above’


Well-known member
Oct 30, 2019
The problem is that the above is NOT bi-amping. You're still driving the same passive crossover that's inside the speakers, but now you're doing it with two amplifiers instead of one.

With good amplifiers (ie, enough current to run the full set of drivers in the cabinets), there will be no measurable difference. Both amplifier channels are putting out the exact same signal, it's just that one of them passes very little current at low-frequencies, while the other passes very little current at high-frequencies. A good amplifier will be happy to pass current over the entire frequency range without any loss of quality.

The real improvement that bi-amping can bring is when it's done properly - with an active crossover.

An active crossover means you've bypassed the speaker's internal crossover, and you've got amplifiers connected directly to the drive units. Think about damping factor, and then what a 0.5ohm (DC resistance) inductor in the crossover will do to that. That's just a small part of the problems of passive crossovers. There's inductor saturation (yes, the crossover components can directly add distortion), the often fairly low-quality capacitors, and of course the limited amount of response shaping you can actually do with a speaker-level crossover.

There's plenty of reading to be done online about active vs passive crossovers, but I'll leave it with this: why do you think almost all studio monitors feature 2-4 amplifier channels per box?



Well-known member
Sep 24, 2008
Bi-amping just means using 2 amplifiers for 1 signal (The type of crossover is irrelevant) so it is correct above.
If you have a less capable amplifier and difficult speakers then using a second amp to bi-amp can give a small improvement.
The ideal scenario is replacement of the passive crossover with an active crossover between the pre-amp and amplifiers, which will make a big difference.
In the real world unless the amp and speakers are totally mismatched, 1 run of standard 2.5mm sq OFC copper cable is all you need and then save up for a better amp to drive the speakers.