Impedance, current and volume levels

[Swerd]

Sorry Swerd, I think I know what you are trying to say, but for clarity, Ohm's Law applies to both DC and AC system…

Thanks for the clarification.

Perhaps I should have said, "Ohm's Law is a simple equation V=IR when it applies to DC electricity if the resistance (R) is constant. Although it also applies to AC, in loudspeakers impedance (Z) varies with the frequency, and the relationship V=IZ is no longer so simple."

 

[vinnyb]

For argument sake, if you wire two complete speakers (with crossovers) in series, then yes you will double the impedance. As you know the impedance will change with frequency but if the two speakers are identical (including the crossovers), then the impedance of each will vary with frequency the same way. If you do that, as TLS said, your little Onkyo will run out of voltage sooner or later. However, if you simply want to run the Onkyo cooler, it will help as long as you keep the SPL low enough because higher voltage for the same SPL will result in lower current. I know this is just theoretical, not that you, or anyone would use two speakers per channel and wired them in series.

Peng, that makes complete sense. Thanks for adding to the discussion.

 

[PENG]

Thanks for the clarification.

Perhaps I should have said, "Ohm's Law is a simple equation V=IR when it applies to DC electricity if the resistance (R) is constant. Although it also applies to AC, in loudspeakers impedance (Z) varies with the frequency, and the relationship V=IZ is no longer so simple."

Thanks Swerd, again it was not directed at you really because I have been around long enough to know you are electrical tech-savvy. As I said I just wanted it to be clear for those who may take it at face value of take it out of context.

 

[PENG]

Peng, that makes complete sense. Thanks for adding to the discussion.

You do know I was half joking right? As TLSG said, you are obviously very capable of understanding the technical stuff we are talking about here. I know you won't actually do it but I have to say it just to be sure.

 

[herbu]

Unfortunately we have a lot of people wandering through here lately who can not understand any explanation no matter how simple and dumbed down.

Thanks for the shout out! We make a good team. I can provide the dumbed down answers, and you guys can handle the technical stuff.

 

[3db]

Thanks for the shout out! We make a good team. I can provide the dumbed down answers, and you guys can handle the technical stuff.

You must be a manager

 

[fmw]

The thing that audiophiles tend to ignore is that amplifier impedance ratings are based on full output power. If you want a lower impedance rating you just need to lower the power rating. Reality is that few home audio installations dissipate more than about 20 watts per channel. At that level all high fidelity amplifiers will handle a 4 ohm nominal impedance with ease. In my bedroom, I drive a pair of 4 ohm speakers with a bottom of the line AV receiver. It never even occurred to me to worry about it. The problems people have with speaker impedance occur around maximum power dissipation.

 

[highfigh]

Peng, that makes complete sense. Thanks for adding to the discussion.

If you built your own amplifiers, do they have a variable input level control? If so, and if they can drive the speakers without a problem WRT impedance, would it make sense to use the Onkyo for switching and its preamp, leaving the power amp(s) to handle the load of the speakers? If the Onkyo has preamp out, this is moot.