Wanted to add does it matter to the amp if it runs at 8 ohms or 4 ohms???
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Depending on the amplifier. If the amp has an output transformer than theoretically it delivers the same wattage to the both loads if the transformer designed so.
If the amp is direct-coupled and has also rating to lower wattage(s) than it's also OK to take lower impedance speaker.
Usually direct-coupled SS amps are even better with lower-impedance loads and cripples on the high impedance loads. The opposite with direct-coupled tube amps(OTL).
Most higher powered amps will not be affected by dropping to a four ohm load. Generally amps output ratings double as the load halves but that is not always the case. A four ohm load is not usually difficult for and amp to drive. I don't think in your case it would make any difference, unless there is something about your amp that I don't know.
Actually, it should only matter if you are going to connect more than 1 pair of speakers to the amp. Usually ... each pair of speakers that you will add will half the total overall resistance of the line and when you get below 2 ohms, it begins to get risky (blowing fuses, etc.). For example, if you have 2 pair of 8 ohm speakers connected to your amp, the line would check in at 4 ohms, which is OK. Now, a lot of speakers rated at 8 ohms are usually operating nominally at 6 ohms, so your line is really at 3 ohms, still OK. Try this with 2 pair of speakers rated at 4 ohms and you can see where you will get closer to the 2 ohms limit. Now, there are also amplifiers that can safely operate at 2 ohms. So ... if you are planning to run more than 1 pair of speakers, you have to be aware of the math. Regards, Rich
First of all, it's not 8 ohms "normal" resistance, its 8 ohms "nominal" resistance, and the word nominal in audio means something like: This is an even less meaningful spec than the others.
Resistance varies with frequency, and the more valuable figure is the minimum load, since that's a better indication of how the speaker will tax your amp.
Also, the fact that your amp specs give a power rating into 8 ohms means nothing. The manufacturer could also have given a power rating into 4 ohms (which would probably be higher).
If you're going to pay attention to specs, you have to know what they mean--and even more important, what they don't mean. In this case, they don't mean much. Buy the speaker that sounds best with your amp, in your room, and you'll be fine.