Speaker Asylum

Posted by DavidLD (A) on July 13, 2002 at 14:42:50

In Reply to: 16 or 8 or 4 ohms in a speaker output? posted by edu7 on July 13, 2002 at 13:42:43:

That's an approximation of the average load across the speaker terminals. Its somewhat like resistance, but it varies with the frequency of the signal/music. THe actual ohms is nifferent at nearly every frequency.

Most receivers or amps are set up to handle an 8 ohm load, and produce somewhat less power with 16 ohms.

Some amps and receivers arent happy running much lower than an 8 ohm load, and in the owner's manual they will suggest you only use 8 ohm speakers. Amps will generally produce more power with a 4 ohm load, but will stress the power supply if the unit is not built for it.
Manufacturers of inefficient speakers sometimes make them 4 ohms because they know most receivers produce more power at 4 ohms. BUT never hook two pair of 4 ohm speakers and play them at once as this generally is a 2 ohm load which receivers like to blow up with.

If you hook up 2 pair of 8 ohm speakers on a receiver, in most cases the receiver will run them in parallel, making a 4 ohm load. Its not a good idea to use more than 2 pair of speakers and run them at the same time on most amps.

Thats the basics, but there is lots more

David