Connecting Speakers in Serial Connection - dangerous? Performance?

sashak

Hello

I was hoping someone can help me with a fairly basic question I have.

I need to find a way to push out signal to two speakers from a single amplifier output. I've been reading up on my options. As amp is not mine ( :-) ) , I need to be carefull. My questions are around consequences.....

1. I likely can't connect the speakers in paralel connection. Each one is 4 ohms and the amp (Yamaha HTR-5730) is rated at 'min 6 ohms' at the back.

2. I am looking at serial connection. My question is what will happen to the 'power' (or realistically, the sound) if I connect the speakers in serial connection. Will (or how much will) the sound 'drop' if I do it.

I understand that paralel connection can damage the amp if the resulting 'ohmage' is low (say below 2 ohms). How risky is the serial connection or is the sound quality (or strength) the only unwanted effect?

Thanks so much in advance

Sasha

rallyshark

I'm sure someone with much more knowledge will chime here, but here's my 2 cents. I believe you mean series(instead of serial). It you connect the two 4ohm speakers in series it should in no way harm the Yami. I don't think it will hurt your sound at all. However, the amp will not put out quite as much power in 8ohms vs 6ohms. Without knowing your exact speakers and use I can't say for sure if it would suit your needs, but I think it probably will work just fine for you. A receiver pushing 8ohms is always better than a receiver that pushes nothing because it got fried:D There are many factors here, so I suggest you list a few more details about your set up if you want much more specific info than this. Good luck:)

F1nut

Each one is 4 ohms and the amp (Yamaha HTR-5730) is rated at 'min 6 ohms' at the back.

You shouldn't use that AVR to drive 4 ohm speakers, period.

comfortablycurt

Keiko wrote: »

+1...That AVR isn't designed to handle a 4 ohm load. Get a capable amp.

+2

Especially since you said the AVR isn't yours. That would be putting a lot of undue stress on it. You don't want to risk that, especially with equipment that isn't yours.

TNRabbit

....he's saying use it at 8 ohms (two 4 ohm speakers wired in series for 8 ohm overall impedance)...

sashak

Thanks a lot for super fast responses guys.

The speakers are not mine either, but I don't have them handy to verify they are indeed 4 ohm.

What if they are 6 ohm each, meaning the resulting impedance of serial connection of 12 ohms? Will that significantly reduce the power? And from the answers above, it looks like it is fairly safe to do it this way, right?

Thanks

Sasha

sashak

Btw...this is a one night setup only....for a bday party only...it won't stay like this for long time :-)

WilliamM2

sashak wrote: »

Thanks a lot for super fast responses guys.

The speakers are not mine either, but I don't have them handy to verify they are indeed 4 ohm.

What if they are 6 ohm each, meaning the resulting impedance of serial connection of 12 ohms? Will that significantly reduce the power? And from the answers above, it looks like it is fairly safe to do it this way, right?

Thanks

Sasha

If you connect them in series, there will be no danger to the AVR. Forget the better safe than sorry comments, it doesn't apply in this situation. As far as power, connecting them in series will cut the power in half.

shadowofnight

As long as the full range speakers used in the series array are identical and share the same crossover design you are fine...otherwise you can run into phase differences/cancellations/etc if their crossover designs are not alike ( 6db per octave/12db/18db etc as well as the many many different implementations of each of those depending on design ( Butterworth/Bessel/Linkwitz-Riley/etc )

Of course impedance changes with frequency, but a quick and dirty general rule for individual speakers ( Re ) works pretty well for full range assembled speaker assemblies in series/parallel .

Basically read the DC resistance in ohms and it will be around 75% of the load it will present to the amplifer for your purposes ( Again, this is not exact as impedance plots vary with frequency, but for series/parallel hookups it is just fine ) . So examples would be 8 ohm rated speakers reading 6 ohms on a multimeter......4 ohm rated speakers reading 3 ohms on that same meter.....2 ohm rated speakers ( Common for my subwoofer build multiple voice coils ) reading 1.5 ohms....etc.


The window for mass produced speakers receiving an 8 ohm rating is huge....I have measured some that never dipped below 5 ohms at any particular frequency on the plot, and others that dropped all the way to just over 2 ohms at certain frequencies :eek: But since this happens for such a small frequency/time period...well built amps ...even those only rated for 8 ohm speakers ...wont complain. Now hook up those types of "8 ohm " speakers to a cheap AVR and you might run into trouble. Most good speaker reviews will include this information in their review.

One just recently, a Polk in fact...surprised me....the RTi A3 that we in the bay area did a demo on. Its measured DC resistance was 3.2 ohms :eek: ....I did not have the equipment at home to get a full frequency plot , but I am guessing it never drops below 5 or so ohms for much of its useful frequency range . It was also discussed on a couple of other forums as well ...




" Axiom rates the M80 as having 4 ohm impedance, but Sound & Vision's Tom Nousaine rated the M80 as 3.0 ohms minimum and 9 ohm nominal impedance.

Polk say its RTi A3 has an impedance of 8 ohms, but Nousaine rates the RTi A3 as 4.0 ohms minimum and 6 ohms nominal.

Don't the results of Nousaine's testing mean that the Axiom speaker is actually an 8 ohm speaker (not 4 ohms), and the Polk speaker is actually a 6 ohm speaker (not 8 ohms). "



Could somebody ( Cmon Bear...I saw/heard your LSi9's ) measure the DC resistance of a 4 ohm rated polk speaker ? I would like to see how it compares to the RTi A3 at DC measurement as well as see both impedance plots for them.


Oh well, I guess it was the strong coffee I made this morning ....but as for the OP....you will be fine hooking those up in series for your party.

Just remember , Take the amps positive to the first speakers positive....then the first speakers negative to the second speakers positive....then the second speakers negative back to the amps negative and you are good to go

WilliamM2

Keiko wrote: »

Yeah, just forget it. If it ends up damaging the gear, William will be happy to pay for it. :rolleyes:

Please explain how hooking two 4ohm speakers in series will damage the amp? It will be an 8 ohm load.:rolleyes::rolleyes::rolleyes::rolleyes:

comfortablycurt

I assume that you're going for big volume here? I've never tried this myself...but I would assume that your volume level here would remain roughly the same. As others have said, connecting them in series would cut the power to each speaker in half...so none of the speakers would be getting driven as hard as they would be with a single pair. My guess is that your volume level wouldn't really be increased.

I'm gonna agree with Keiko on playing it safe though, as it's not your gear. You don't want to take the chance of f-ing up someone elses gear if it can be helped.

comfortablycurt

Keiko wrote: »

Curt gets it. :rolleyes:

And I'm even a newb.

WilliamM2

Keiko wrote: »

I already explained my thoughts and gave an opinion William. Go back and re-read what I said. Apparently you missed it the first time.

You mean this?

+1...That AVR isn't designed to handle a 4 ohm load. Get a capable amp.

It's an 8 ohm load.

Or did you mean this?

I have a vague idea of what your asking as to how to set up these speakers, but I've never tried it and have no experience.

WilliamM2

Keiko wrote: »

Typical of you William. Go look for your Drama somewhere else.

You seem to be the one looking for drama. It is safe to hook an 8 ohm load to that avr, whether it's an 8 ohm speaker, or two 4 ohm speakers in series.

comfortablycurt

WilliamM2 wrote: »

You seem to be the one looking for drama. It is safe to hook an 8 ohm load to that avr, whether it's an 8 ohm speaker, or two 4 ohm speakers in series.

The fact that the gear belongs to someone else comes into play though. Accidents happen. They're more prone to happen when you're using slightly more unorthodox methods of achieving your results.

The way I'm seeing it here...no one is trying to argue with you that it "can't be done", just that in this specific situation, it may be best off to avoid it anyway.

As said before, there aren't going to really be any advantages to this method anyway...

Face

A serial connection will be safe, it just won't sound as good.

Mike21

On paper, what the OP wants do should not be a problem.

However, home audio components, unlike pro components, are not designed for series operation.

Accordingly, I would not freak around w/ someone else's stuff.

ben62670

Face wrote: »

A serial connection will be safe, it just won't sound as good.

+1 If you hook up 2 speakers in series that have crossovers in them the second set will sound like crap if not both. It won't hurt them, but...
Ben