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Dale M
09-22-2004, 07:33 PM
Hi, A friend of mine asked me today what would happen if he spliced the left and right front speakers wires from his receiver and used 4 speakers instead of 2,, and I said ummm I dont know but Id ask some people that do. So is this ok to do? does it cut the output to his front speakers in half?,
Thanks
Dale M

cam
09-22-2004, 07:50 PM
That would be running your speakers in parallel. If you run two 8 ohm speakers from one output your receiver will see it as 4 ohms. Your amp will shut down if listened to at loud levels. Low to moderate volume would be fine. You can lessen the load the amp sees by running your speakers in series, one positive to positive of speaker 1, negative to negetive to speaker 2 and then join the left over pos and neg together. Then repeat this for the other side. Your amp will now see two 8 ohm speakers as 16 ohms which your amp will easily be able to drive. I don't know how accurate the speakers will sound together considering that these are your front speakers, but I know people do it with their surrounds with success but then total accuracy would be less crucial or even noticable with your surrounds.

Lensman
09-22-2004, 09:35 PM
You can lessen the load the amp sees by running your speakers in series...Your amp will now see two 8 ohm speakers as 16 ohms which your amp will easily be able to drive.

Does that do anything the power load on the speakers? I'd actually considered doing that with 4 old Minimus 7 speakers I've got lying around as an experiment to see how dipoles would sound in my positionally challenged room, but fear I it might make it easier to blow them as they're only rated to 40 watts and my receiver puts out 70.

cam
09-23-2004, 02:15 PM
Does that do anything the power load on the speakers? I'd actually considered doing that with 4 old Minimus 7 speakers I've got lying around as an experiment to see how dipoles would sound in my positionally challenged room, but fear I it might make it easier to blow them as they're only rated to 40 watts and my receiver puts out 70.
When you run a pair of speakers in series you would not be creating a di-pole effect. A true di-pole has the forward facing speakers in phase and the rearward facing speakers out of phase. If anything you would be creating a bi-pole. Hook them up and experiement, you might like it or not. Once you have two speakers run in series off of one channel you will now have to up your volume to achieve the same db's.

E-Stat
09-23-2004, 02:18 PM
Hi, A friend of mine asked me today what would happen if he spliced the left and right front speakers wires from his receiver and used 4 speakers instead of 2,, and I said ummm I dont know but Id ask some people that do. So is this ok to do? does it cut the output to his front speakers in half?
"Doubling" speakers is not a new concept. Audiophiles doubled the famous KLH 9 electrostat back in the 60s for greater output and bass response. The Double Advent system of the early 70s was quite popular and there was a particular synergy with using a stacked pair. The usual way to double bookshelf speakers is to invert the top pair in a quasi D'Appolito fashion.

As suggested by cam, paralleling speakers drops the nominal impedance in half and a number of receivers are not well suited for such loads. On the other hand, there are quite a few power amps that can handle lower impedance loads and usually their power output is higher at those lower loads. All things being equal, you will generally get an additional 3 db of output using a double pair of speakers.

rw

Geoffcin
09-23-2004, 03:22 PM
Hi, A friend of mine asked me today what would happen if he spliced the left and right front speakers wires from his receiver and used 4 speakers instead of 2,, and I said ummm I dont know but Id ask some people that do. So is this ok to do? does it cut the output to his front speakers in half?,
Thanks
Dale M

And it can be done. But I would not recommend it with just a receiver, as you could easily overload it, and wind up with a toaster instead.

The way I do it is I split off the preamp out from the receiver, and send it to a dedicated amp for one of the speaker sets. If I just tried to hook then all into the receiver there might be problems. I've got too much invested in this gear to play around and find out.

kfalls
09-24-2004, 05:30 AM
You guys are making way too much out of this. Just connect the additional pair of speakers to the 'B' speaker terminals on your receiver. Many, if not most receivers give you options to to have either 'A' speakers on, 'B' speakers on, or both on. In general with both selected the speakers are in parallel.

The limitation of how much you can drive both pairs is determined by how robust a power supply you have. If it's a high wattage receiver (90W+) and the outputs can handle the current of a 4ohm load you should be able to listen at moderate levels. It also depends on how efficient your speakers are. A +3db difference in speaker efficiency (90db over 87db)would take half as much power for the same listening level.

Look at the power supply specs. many give their maximum continuous output in 8ohm, 4ohm or in the case of most Onkyo receivers 6ohms. Having a selection for both 'A' and 'B' speakers is not a guarantee you can drive both pairs at once, since efficiencies vary. But if you have a higher wattage receiver it should be safe to run both pairs at moderate levels.

eqm
09-24-2004, 07:54 AM
Hi, A friend of mine asked me today what would happen if he spliced the left and right front speakers wires from his receiver and used 4 speakers instead of 2,, and I said ummm I dont know but Id ask some people that do. So is this ok to do? does it cut the output to his front speakers in half?,
Thanks
Dale M

the main questions should be "why? what do you want to get out of doing this?" your receiver can only send so much power without adding a lot of distortion. Can your receiver hookup A+B speakers without a drop in volume from either set of speakers? If not, stick with the single set and realize that's the best you'll get until or unless you upgrade your power amp. Experimentation is always fun, but in this case it may bring more harm than good!