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Discussion Starter · #1 ·
Okay, for some reason I'm not getting this (maybe early morning without coffee).


In summary, I'm installing a Russound CAA66L system, which outputs 20w at 8 ohms (each connection supports four wires).


I'm using Phoenix Gold ATC6DM speakers, which have a 16/8 ohm selector. These are a single speaker with four wires, but can output stereo or mono. In this case, I'm using them in a single room with stereo.


Per the FAQ/Manual, I'm supposed to set the selector to 16 for single room/stereo mode. This will result in 16ohms being split between two tweeters.


"Why is your “Dual Mono” speaker unique?

The ATC6DM / ATC8DM models are unique because they are dual-function speakers. They can be used as “summed” mono speakers as well as in conventional stereo pairs (when two are used). This is achieved by setting the 16/8 ohm switch on the back of the unit. The switch is set to the 16 ohm position if you are using it as a summed mono speaker (both L&R channels connected). The switch is set to the 8 ohm position to use as “single mono” speakers in a standard two-speaker stereo format."


Now, here's my dilemma. How do I wire TWO of these speakers (in separate rooms) both with stereo sound that use the same 16/4 speaker wire and connect to a single input on the Russound system? And, what would I put the switch on - 16 or 8?


Is there some sort of formula for calcuating this stuff, and then telling me if it should be wired in series or parallel?
 

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I'll try to simplify this as much as possible


When connecting speakers in "Series" is by connecting a speaker positive terminal to the amps positive terminal, then the negative terminal to the next speakers positive terminal...daisy chaining them. At the last speaker in the chain, its negative terminal will then return to the amps negative terminal. By doing this if looking at the resistance as seen by the amplifier, each speaker will be adding its resistance into the total, as there is only one path for electrical current to flow. So the total resistance as seen by the amp (Rt) is R1+R2+...+Rx, where R is speaker resistance (Rt is speaker total resistance).


Now connecting in "Parallel" is by connecting all the positives together (amp and speakers) and connecting all the negatives together. This will yeild a total resistance (as seen by the amp) as a fraction of the individual speaker resistance. Example, take two 8 ohm speakers and wire them in parallel, you will measure a total resistance of 4 ohms.


Keep in mind that by reducing the resistance seen by the amplifier will drive the amp harder.


Now with all that being said, in your application, if you have one run of 16/4 from the amplifier, then jump from the first speaker to the second speaker with another 16/4 run. Just match wire color to speaker terminals at both speakers and that the wires you connect the speaker positive terminals go to the amplifier positive terminal, and wire going to speaker negative terminal go to the amps negative terminals. If you flip the switch of each speaker to the 16 setting, then the amp should see an 8 ohm load, and that 20w will be distributed across the two speakers, so in theory each speaker will be driven by 10W.


If the amplifier can handle a 4 ohm load, then you could switch the speakers settings to 8, and it should all still fall within the limits of the amp.


Here's a good image of the difference between Series connection to Parallel connection:



Parallel connection made at speakers (I think this is your type of setup)



Sorry for the long winded post, but in the end...I hope it all helps.
 

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I have a related question... I'm setting up a Nuvo Essentia system and decided to put in speaker terminals in each room so that i can tap into them with a powered subwoofer.


According to your diagram, I'll be wiried in Parallel, using the speaker level inputs on the sub.


Since the sub is powered, does is still have a resistance?


Thanks,

Chris
 

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Most likely in the powered sub there is a buffer circuit, as well as a filter (to keep it simple). The buffer will bring the signal from speaker level down to line level (~2Vp-p), and then a filter to get rid of the high frequencies. The buffer should be high impedence on the input, so in comparison to other speaker connections as seen by the amp, it will be somthing like a 10kohm load in parallel to an 8 ohm load (speaker). So according to Kirchoff's Law of electrical resistance the equations is Rt=(Ra*Rb)/(Ra+RB) or (10k*8)/(10k+8)=7.99 ohms resistance seen by the amp.


A quick check is easy to do, by taking a resistive measurement at the sub's speaker inputs. Or make all your connections at the speaker end, then take a multimeter and measure the resistance at the amp end. Depending on your other speaker connections, I think you will find that the resistance will be close to the indicated speaker value on your external speaker from the powered sub


I can do a quick check when I go home tonight, as I have a couple of amps that have the option of accepting speaker-level connections (car audio days)...though I have never used those connections.
 

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thanks, this is helpful. sounds like i'll be ok wiring this way.


i dont have the tools to measure the resistance, so i will try it out this weekend and see if it blows up



Chris
 

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Hello,


i am installing a nuvo essentia eg and I want to put 4 of the 6.5" accent plus 1 speakers on one zone. Is this going to work and should I wire parellel or series?


Thanks
 
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