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wendans
05-29-09, 09:19 AM
I am wiring a Russound Cav6.6 and need to check something out. I am going to need to wire in a series a group of speakers. There will be two in one room and a stereo speaker in another and they need to be wired in series because it is too hard on the amp if wired in parallel. I am using 16/4 speaker wire and just want to reassure myself I am doing it right.
Can anyone tell me or show me how they would do it?
Can anyone tell me or show me how they would do it?
Rick Johnston
05-30-09, 07:14 AM
Parallel wiring means that all + (plus) wires are connected to the + terminals, and all - (minus) wires are connected to the - terminals. A daisy-chain.
Series wiring means the + wire from the amp is connected to the + terminal of the first speaker. The - of the first speaker is connected to the + of the next speaker and so on. The - terminal of the last speaker is connected to the - terminal of the amp. A large loop.
Series/parallel wiring is a combination of both, where multiple loops of series speakers are connected in parallel to other loops.
More info is needed in order to do this right. We need to know the impedance of each speaker, and the output impedance of the amp. This is where it gets tricky, because the power in a series/parallel circuit also has to be balanced or one speaker or set of speakers could get too much power.
Two easy formulas are used to calculate the load on a given speaker circuit. ZT is the total impedance, and Z1, Z2 are the impedances of the individual speakers.
For series wiring: ZT= Z1 + Z2 + Z3 ...
Say you have two 8-ohm and one 4-ohm speakers in series:
ZT = 8 + 8 + 4
ZT = 20 ohms
For parallel wiring: ZT = 1 / (1/Z1 + 1/Z2 + 1/Z3 ...)
Say you have two 8-ohm and one 4-ohm speakers in parallel:
ZT = 1 / ( 1/8 + 1/8 + 1/4)
ZT = 1 / ( .125 + .125 + .25)
ZT = 1 / .5
ZT = 2 ohms
Now say you wanted those three speakers to connect to an 8-ohm amp.
Two 8-ohm speakers in parallel:
ZT = 1 / (1/8 + 1/8 ) = 4 ohms
Connect that parallel circuit in series with the 4-ohm speaker:
ZT = 4 + 4 = 8.
And therein lies a problem: The single 4-ohm speaker will get twice as much power as the two 8-ohm speakers.
Series wiring means the + wire from the amp is connected to the + terminal of the first speaker. The - of the first speaker is connected to the + of the next speaker and so on. The - terminal of the last speaker is connected to the - terminal of the amp. A large loop.
Series/parallel wiring is a combination of both, where multiple loops of series speakers are connected in parallel to other loops.
More info is needed in order to do this right. We need to know the impedance of each speaker, and the output impedance of the amp. This is where it gets tricky, because the power in a series/parallel circuit also has to be balanced or one speaker or set of speakers could get too much power.
Two easy formulas are used to calculate the load on a given speaker circuit. ZT is the total impedance, and Z1, Z2 are the impedances of the individual speakers.
For series wiring: ZT= Z1 + Z2 + Z3 ...
Say you have two 8-ohm and one 4-ohm speakers in series:
ZT = 8 + 8 + 4
ZT = 20 ohms
For parallel wiring: ZT = 1 / (1/Z1 + 1/Z2 + 1/Z3 ...)
Say you have two 8-ohm and one 4-ohm speakers in parallel:
ZT = 1 / ( 1/8 + 1/8 + 1/4)
ZT = 1 / ( .125 + .125 + .25)
ZT = 1 / .5
ZT = 2 ohms
Now say you wanted those three speakers to connect to an 8-ohm amp.
Two 8-ohm speakers in parallel:
ZT = 1 / (1/8 + 1/8 ) = 4 ohms
Connect that parallel circuit in series with the 4-ohm speaker:
ZT = 4 + 4 = 8.
And therein lies a problem: The single 4-ohm speaker will get twice as much power as the two 8-ohm speakers.
wendans
05-30-09, 10:55 AM
I figured it out. Both sets of speakers were of the same brand and same ohms rating. Thanks for all the info anyways.