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Speakers to be wired Parallel or Series?

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Rob Swain:
Hello, I'm helping out with a very simple Sound System in a very old church, built in 1922, with high ceiling etc, seats around 600 people. System uses only two Mic's,  one Lector Mic, and the other a Headset Countryman E6 used with a wireless PGXD Shure.  They have a mixer with a Feedback Terminator, Digital Eq and a Yorkville CR5 Dual channel Amp. Main speakers  2 Yorkville  8 Ohm's, which run on one channel of the Amp. The Monitor speakers, also Yorkville 8 Ohm,  run off the other channel.  Although the church seat 600 people, its never usually filled to capacity, therefore controlling sound volume with the Unman-ed Sound system can be a problem.  I find to get any kind of decent gain structure, the Amp needs to be turned way down, so that everything in front of the Amp can be turned up ( which is not much) to produce a clean sound. Now to my question, because the speakers  are parallel on one channel, and they will be running at 4 Ohm's and double the power, is it feasible or possible to connect them in series, to bring them back to  8 Ohm's, therefore making it possible to turn up the Amp?   I should mention that the speakers are hardwired to the Amp, but use 1/4 phone connection on the speakers. Thanks!

Rob

Stavross (Sam Buck):
When you say clean sound what do you mean? Are you getting hum, static, or crackeling?

I'm going to say that you are going to be fine running the speakers the way they are, but you may have something amiss ahead of them.

Art Welter:

--- Quote from: Rob Swain on February 16, 2011, 09:18:44 am ---Main speakers  2 Yorkville  8 Ohm's, which run on one channel of the Amp. The Monitor speakers, also Yorkville 8 Ohm,  run off the other channel.  Now to my question, because the speakers  are parallel on one channel, and they will be running at 4 Ohm's and double the power, is it feasible or possible to connect them in series, to bring them back to  8 Ohm's, therefore making it possible to turn up the Amp? 

Rob

--- End quote ---

Two eight ohm speakers in series are 16 ohms. Your amp will only produce about 1/4 the power at 16 ohms as at 4 ohms, which would reduce your noise (and headroom) by about 6 dB. Reducing headroom makes it easy to clip the amp, which sounds a lot worse than noise.

The correct way to get optimum S/N is as you have done, by reducing the amplifier gain, and running the upstream gear close to 0 VU.

If you are concerned with people raising the amp gain knobs, you could put in attenuator pads prior to the amp, which would do almost as well for S/N as reducing the amp inputs, and allow the amps to be run wide open.

Rob Swain:
Yes, your right! Thanks for the clarification, will leave things as they are!
Rob

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