Rear speakers (1 Viewer)

[richard_v]

I have a 6.1 receiver. I've been told that two (2) back speakers are better. Is it OK to connect two rear speaker out of the receiver's single rear speaker terminal?

 

[Wayne A. Pflughaupt]

For that it’s best to check your manual and see what the manufacturer recommends, Richard. However, off the top of my head I’d say that if the receiver was designed to accommodate two rear speakers, there would be two sets of speaker terminals.

Regards,
Wayne A. Pflughaupt

 

[Iver]

It depends on the way you wire the speakers and the ratings of your receiver.

For example, if you connect two 8 Ohm speakers in series (positive connection of speaker A to positive sixth-speaker connection on receiver, negative connection of speaker A to positive connection of speaker B, negative connection of speaker B to negative sixth-speaker connection on receiver), you will create a 16 Ohm load for the sixth-speaker amp output connections on the receiver.

You need to know if your receiver can handle the 16 Ohm load. This might be labeled on the back of the receiver or the information might be in the owners manual. Some receivers have slide switches on the back that let you set them for different resistance levels.

On the other hand, if you connect two 8 Ohm speakers in parallel, joining the two positive leads together before connecting the combined line to the positive sixth speaker connection and joining the two negative leads together before connecting the combined line to the negative sixth speaker connection, you will create a 4 Ohm load.

For the parallel approach, you need to keep an eye on the lowest resistance, in Ohms, with which the manufacturer rates operating the receiver. As a general rule, you would probably be safer going with the series approach and the 16 Ohm load but it all depends on the manufacturer's rating for the receiver.

If you want to calculate the speaker resistances for other values, here are the formulas. This site also shows you how to figure the resistance for a circuit with a combination of series and parallel resistances, if you should wish to do so.

 

[Wayne A. Pflughaupt]

Neither of these scenarios is very desirable.

For the series connection, the resulting 16-ohm load will reduce maximum power output by one half. So, your 100 watts will be reduced to only 50 watts. Then your 50 watts is essentially divided between the two speakers, so you end up with each speaker getting only 25 watts max.

Few multi-channel receivers can effectively handle the parallel connection and the resulting 4-ohm load. The loading switch on the back can make the receiver handle 4-ohm loads better, but it accomplishes this by loading the connection with a resistor network, so that the receiver “sees” a more optimal load. The result is that power output is limited once again.

Regards,
Wayne A. Pflughaupt