Impedance and the Concerto

[IVB]

I was just looking up what the impedance needs of my Concerto is. It claims 6 Ohms. I have homerunned all my speaker cable, and connected each pair of 8Ohm speakers directly into each zone.

So...is this considered parallel wiring, given that they terminate directly into the Concerto speaker block? If so, that's 4 Ohms, which is below the minimum. But, that doesn't sound right, as I can't see how anyone would run wiring any other way, esp if you only have a pair of speakers in a given zone.

I was hoping to be able to combine 2 rooms into a single zone, but given that the speaker wiring is all already run, I can't actually put it in series now at the head-end. Or am I just too tired, and need to go to bed?

 

[tmbrown97]

Since all your speakers are homerun, you can do all kinds of tricks with your impedance. Depending on series vs. parallel, you either cut the resistance in half, or double it. Or technically, you could do a combination of both, allowing you to hook up 4 speakers and not change your resistance (just lose power to each speaker).

Also, 6 ohms is generally the lowest you can go... You should be fine running at 8ohms or higher all you want. If you have 2 rooms with 2 speakers each, series one set, series the other set, then parallel the two onto one zone (or vice versa) - and you have 8ohms.

Even using 2 speakers per zone - if you series them, you're at 16 ohms, so still safe. Parallel is what'll overheat your amp if used at the wrong time.

 

[charliebarns]

Hey IVB I'm essentially in the same boat as you, sorry I hope I'm not hijacking. I have a room that will have 4 speakers, 8ohms each, using the Concerto P2100 that has a nominal impedance of 8ohms at 70W. I'm trying to determine how to best wire these and I assume it's a combination of series/parallel. the one place I'm confused is the amp is a two channel amp (left and right) and I think to use both channels I need to use positive from left channel and negative from right channel, with the series/parallel wiring in between. Am I correct of way off base here? this should give me 8ohm load in total with 4 speakers....

Thx

Charlie

 

[WayneW]

I have a room that will have 4 speakers, 8ohms each, using the Concerto P2100 that has a nominal impedance of 8ohms at 70W.

Is that 4 speakers = 2 stereo pairs? or 4 mono speakers?
The P2100 supports 4 ohm loads, so you could put 2 8ohm speakers in parallel on each channel.

the one place I'm confused is the amp is a two channel amp (left and right) and I think to use both channels I need to use positive from left channel and negative from right channel, with the series/parallel wiring in between.

That technique is known as amp "bridging" and should only be done on an amp that supports it. Typically amps that support this have a mode switch to enable bridging. You also need to consider getting the same signal into both amps when bridging as a bridged amp provides a single larger mono signal, rather than two smaller stereo signals.

 

[charliebarns]

Yes 4 speakers, 2 stereo pairs. I'll have to contact Nuvo about bridging but I suspect it's a no no otherwise wouldn't they have it listed in the specifications? I suppose I could also put 2 speakers in series on one channel, with a 16ohm load correct? From what I've read it's ok to go higher on the ohm load on an amp, just not lower. Which is better, series or parallel?

Thanks!

 

[WayneW]

Yes 4 speakers, 2 stereo pairs. I'll have to contact Nuvo about bridging but I suspect it's a no no otherwise wouldn't they have it listed in the specifications? I suppose I could also put 2 speakers in series on one channel, with a 16ohm load correct? From what I've read it's ok to go higher on the ohm load on an amp, just not lower. Which is better, series or parallel?

Welcome to CT, Charlie!

Yes, I agree that bridging the NuVo is probably not supported since they assume you are interested in stereo. For the P2100, You could put 2 8ohms in parallel (net 4 ohms) or 2 8ohms in series (net 16 ohms). A 4 ohm load will draw more power from the amp, allowing it to play louder if needed, but it will also run warmer and be stressed more. For normal modest/background music listening levels, I don't think it matters much about series or parallel. IIRC, the GC doesn't support 4 ohm loads, so you would want the series wiring to produce a 16ohm load.

 

[charliebarns]

thx for the feedback Wayne. I've decided to wire in series to reduce the amp loading, and use an external amp where I have more than 4 speakers. I appreciate your advice.

Charlie

 

[CalypsoCowboy]

I have the Simplese, does anyone know if it will harm the system to run different impedance on different zones?

For example,
Zone 1: 1 8 ohm left channel and 1 8 ohm right channel
Zone 2: 2 8 ohm speakers in series for 16 ohms on the left, and 2 8 ohm speakers in series for 16 ohms on the right side?

 

[WayneW]

I have the Simplese, does anyone know if it will harm the system to run different impedance on different zones?

For example,
Zone 1: 1 8 ohm left channel and 1 8 ohm right channel
Zone 2: 2 8 ohm speakers in series for 16 ohms on the left, and 2 8 ohm speakers in series for 16 ohms on the right side?

You should be fine, the zones will be slightly different in volume is the only downside.