How should I install properly more than two loudspeakers connected to a radio player?
I want to install one loudspeaker in each room of my flat. All of them should be connected to the same device. How can I calculate the characteristics of the loudspeakers, how should I wire them? Thanks
The best thing to do is to get an amplifier with multiple speaker outputs. You connect one pair to each set of terminals and a switch on the front panel will allow you to independantly control the speakers.
Another way (if your amp only has one set of outputs) is to wire them in a matrix to keep impedances the same. Note that this method requires you to use speakers all of the same impedance - this is given in ohms and is written on the back of practically every speaker made. 2 speakers in parallel halve the impedance; two 8 ohm speakers will therefore appear as a 4 ohm load to the amplifier. Those same two speakers in series will add up 16 ohms. You therefore need to connect two series pairs of speakers in parallel to keep the whole resistance up/down to 8 ohms.
Of course, this is only for one channel so with a stereo amp you’ll end up with eight speakers - a matrix of four for each channel. If you want only four speakers in total, you can normally get away with two speakers in series for each channel.
If you don’t use all the exact same model/brand and mix speakers, some will be louder than others as sensitivity changes from speaker to speaker. This is given in decibels per watt at 1m; eg. 86db 1w/m. This means if it is fed 1 watt of pink noise, it generates 86db measured from 1 metre away. Try to get all your speakers to be of similar ratings to avoid big differences in volume.
The best thing to do is to get an amplifier with multiple speaker outputs. You connect one pair to each set of terminals and a switch on the front panel will allow you to independantly control the speakers.
Another way (if your amp only has one set of outputs) is to wire them in a matrix to keep impedances the same. Note that this method requires you to use speakers all of the same impedance - this is given in ohms and is written on the back of practically every speaker made. 2 speakers in parallel halve the impedance; two 8 ohm speakers will therefore appear as a 4 ohm load to the amplifier. Those same two speakers in series will add up 16 ohms. You therefore need to connect two series pairs of speakers in parallel to keep the whole resistance up/down to 8 ohms.
Of course, this is only for one channel so with a stereo amp you’ll end up with eight speakers - a matrix of four for each channel. If you want only four speakers in total, you can normally get away with two speakers in series for each channel.
If you don’t use all the exact same model/brand and mix speakers, some will be louder than others as sensitivity changes from speaker to speaker. This is given in decibels per watt at 1m; eg. 86db 1w/m. This means if it is fed 1 watt of pink noise, it generates 86db measured from 1 metre away. Try to get all your speakers to be of similar ratings to avoid big differences in volume.
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