Speaker's impedance

[ynotamil]

Greetings to all,
I bought a pair of Jamo C 603. The impedance of those speakers is 6 omhs. My Sony 2400es AV can only be set to either 4 or 8 ohms. The suppliers of the speakers told me that I must set it to 8 omhs, but I already read somewhere that I must always set to the lower impedance, in this case to 4 ohms. I just can not find where I read that article, so I am a bit worried if I pick the wrong impedance.
What should I do? 4 or 8 ohms?
Thanks,

Tony
 

[dotVIBE]

set to 8 ohms. your amp will be happy with that.

i could give you the long detailed explanation, but i'm off to bed. sorry. you're gonna have to trust me.

[Ampdog]

If the amplifier is well-designed, it should not matter. Your maximum output will be lower by 3dB on 4 ohm, which also will not make a big difference. Depending on the cabinet design of the loudspeakers, the actual l.s. impedance would be higher than 6 ohms at most frequencies. The 4 ohm recommendation probably came out of worry that strictly speaking you will overload the amplifier by placing 6 ohm across an 8 ohm output impedance. That is true for sine wave signals, but with the low average level of most music that should not be a factor

[dotVIBE]

Right,

If set to 4ohms your receiver will actually lower it's power output to protect itself from clipping, while at 8ohm you will get the full capabilities of the amps.

[ynotamil]

Thank you all that replied.
I was going to ask another question what kind of damage could be done to the A/V or to the speakers,
but that was already answered.
Thanks again.
Tony

[Viagara]

The 4 Ohm/8 Ohm switch on AVR always intrigue me. Why build something that has to be protected against itself? Or is it a case of so many shortcuts being taken with AVRs that you need this kind of protection and I am not talking about the builtin protection against clipping, etc which is found in some stereo integrateds.

Okay, just my bit of rant and rave

[Neil]

i agree surely with todays electronics - it can think for itself - like the cars of todays, the are just super computers on wheels!!

[ynotamil]

The 4 Ohm/8 Ohm switch on AVR always intrigue me. Why build something that has to be protected against itself? Or is it a case of so many shortcuts being taken with AVRs that you need this kind of protection and I am not talking about the built in protection against clipping, etc which is found in some stereo integrateds.

Okay, just my bit of rant and rave

Hang on; I thought that the impedance setting on the AVRs was to protect the speakers. Your post leads me to conclude that the setting is to protect the AVR. Which is which?

Tony

[Viagara]

Hang on; I thought that the impedance setting on the AVRs was to protect the speakers. Your post leads me to conclude that the setting is to protect the AVR. Which is which?

Tony

Exactly what I meant, its not to protect your speakers, but rather your AVR

[Neil]

leave your amp on 8ohms and let it do its thing, these impedance selectors just confuse people, if it was'nt there, this thread would'nt have been created.  if you dont happy, change your amp 

[ynotamil]

Exactly what I meant, its not to protect your speakers, but rather your AVR

It looks like that for you it is a too basic question, but for me it is a big mystery: how can the AVR be damaged if one sets it with a wrong impedance?
Against the comment of dotVIBE above:
""If set to 4ohms your receiver will actually lower it's power output to protect itself from clipping....""
I am more confused: isn't clipping a problem for the speakers? How does the AVR damage itself if it goes into clipping?
Isn't his further comment:
"" .............while at 8ohm you will get the full capabilities of the amps.""
contradict himself and the general recommendation of this thread, in advising me to go to a higher setting?
Sorry to take you back to basics, but my knowledge in this field is close to zero.
 
Tony

[Neil]

i have an idea, experiment, put it on 8 ohms and crank it till it starts distorting, then do the same thing on 4 ohms and see if there is a difference...that's what i would do...

physically test the theory, you aint going to break anything, you just going to find the limit of both speakers and amp.

[Viagara]

It looks like that for you it is a too basic question, but for me it is a big mystery: how can the AVR be damaged if one sets it with a wrong impedance?

My apologies if I oversimplified your question. To me it is an issue that with many(of not most) entry-level AVRs so many corners are cut to bring production costs down, that the manufacturers have include a silly thing such as a 4 Ohm - 8 Ohm switch. The mere fact that there is such a switch confuse people and it can potentially become an issue to them. The best advice thus far is that of dotVibe to leave the switch on 8 Ohm and just enjoy your setup. Neil also has a valid point.

You are quite right that clipping is not good for speakers, specifically your tweeters, but I am sure the AVR will give up before your speakers does.

Now experiment and use your ears to find out what you enjoy Then experiment with speaker placement and enjou even more

[Neil]

on my yamaha rxv450, i also have an impedence switch which i have never touched - i just left it on 8 0hms...in the old days - especially the nad they had these switches - just a gimick really, when you think about all the filters that they used to have on amplifiers back in the 80's, your treble filter, loudness button all sorts of other filters - which if you think about it - never really worked...just gimmicks.

I was happy with an amp with no tone controls (not needed with cd only the days of playing tapes and records would you really think about tweaking it a bit).  I used to run my onkyo a9210 amp with the tone controls bypassed all the time, and loudness button off - and goei volume!

[Viagara]

in the old days - especially the nad they had these switches

The switch on the NADs had nothing to do with impedance, it was to limit clipping. They still have that on their stereo amplifiers, not sure of their AVRs though.