Current Questions

More and more, I see the word “current” in audio reviews. The reviewers warn me that I’ll “need lots of current” for a given speaker but they don’t explain exactly what it is I need or how many “lots” is. I’ve looked at a few “Electronics For Dummies”-type sites but I’m still confused. A few questions:

—What is current?

—When someone writes, “These speakers need a lot of current,” what do they mean? Is sensitivity involved? Impedance?

—On the amplifier end, what specification measures current?

—Are there subjective considerations at work in that spec? The number of watts doesn’t tell me everything about loud an amplifier sounds. Does the number of [whatever measures current] similarly leave things unexplained?

—Everyone asks, “How many watts?” No one asks, “How much current?” Is it really so important?

paul600103-25-2022 6:22am

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twoleftears Details Discussions Posts This discussion Message User 5,320 posts 03-25-2022 at 05:20pm Copy Comment URL Report Comment Edit Delete
carlsbad Details Discussions Posts This discussion 1,551 posts 03-25-2022 at 10:25pm Copy Comment URL Report Comment Edit Delete So far this thread doesn't have electrical misinformation in it. It will soon. I like homes' explanation. I is current. R is resistance. Someone will eventually point out that a speaker isn't a purely resistive load but his explanation is a good way to look at it. if you halve the resistance (R) you will approximately double the current (I). In my first physics class I asked why C wasn't used for Current and never got a good answer. i have a physics degree from the University of Chicago. So we will keep using I for current. I'll add one more thing: many good amps will provide double the power to a 4 ohm speaker as it is rated for an 8 ohm speaker. but some can't. That is generally a current (amps) limitation. Jerry
audition__audio Details Discussions Posts This discussion Message User 1,580 posts 03-25-2022 at 10:52pm Copy Comment URL Report Comment Edit Delete True about power doubling, but the real issue is not many amps sound nearly as good driving a 4 ohm load as they do driving a 8 ohm load or higher. This isnt just true of tube amps.
jjss49 Details Discussions Posts This discussion Message User 6,612 posts 03-25-2022 at 11:52pm Copy Comment URL Report Comment Edit Delete more grist for the mill
invalid Details Discussions Posts This discussion Message User 1,262 posts 03-26-2022 at 12:16am Copy Comment URL Report Comment Edit Delete Technically speaking no amp can really double it's power when resistance is halved, the manufacturer underrates the 8 ohm power output to come up with that figure.