i have a pair of 6x9 coaxial 4-way speakers (well its more really 2 way but it has 2 extra tiny piezo tweeters that don't really do anything so lets just call it a 2 way)
they say they are rated for 75W RMS and 300W peak but somethings not right
I started tuning my amp and at just under 60 watts RMS I smelled something when i put my nose next to the speaker and so i turned it back down to about 30 watts RMS (about 10 to 11v AC going into the speakers) and they seem fine at 30 watts RMS doesnt smell or get too hot
but they seem to be fine now i don't hear any weird mechanical noises
i want to know if they are no good anymore cause they started smelling like cooked speaker a little bit for a second
I didn't see any smoke though.
they are each in an 0.5 cubic feet per speaker sealed boxes with polyfill stuffing. is the box too small or something?
they weren't even close to reaching mechanical limits. when testing them free air they flex like crazy but in the box they barely move a few millimeters at the same power
they say they are rated for 75W RMS and 300W peak but somethings not right
I started tuning my amp and at just under 60 watts RMS I smelled something when i put my nose next to the speaker and so i turned it back down to about 30 watts RMS (about 10 to 11v AC going into the speakers) and they seem fine at 30 watts RMS doesnt smell or get too hot
but they seem to be fine now i don't hear any weird mechanical noises
i want to know if they are no good anymore cause they started smelling like cooked speaker a little bit for a second
I didn't see any smoke though.
they are each in an 0.5 cubic feet per speaker sealed boxes with polyfill stuffing. is the box too small or something?
they weren't even close to reaching mechanical limits. when testing them free air they flex like crazy but in the box they barely move a few millimeters at the same power
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Just a test tone of -0dB from my computer. i was using a digital multimeter to measure the true RMS AC voltage from the amplifier going into the speakers
My other set of speakers rated for 40W RMS have no problem being set up the same way with 40W RMS going to them playing a test tone they dont even get hot they could play it all day long.
but these speakers seem to be 50% overrated or something because i didnt think they would already start smelling before they even reach 70W of power. i just want to know if the speakers are going to be useable still. the impedance measures correctly. and i dont hear any scraping or weird mechanical noise. but i dont know if they are going to stay that way with some normal usage.
My other set of speakers rated for 40W RMS have no problem being set up the same way with 40W RMS going to them playing a test tone they dont even get hot they could play it all day long.
but these speakers seem to be 50% overrated or something because i didnt think they would already start smelling before they even reach 70W of power. i just want to know if the speakers are going to be useable still. the impedance measures correctly. and i dont hear any scraping or weird mechanical noise. but i dont know if they are going to stay that way with some normal usage.
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Amplifying a test tone (you don't say what frequency) to this extent is one way to overheat a speaker.
The 75W RMS rating is more likely to apply to an everchanging music signal and, even then, is probably inflated by the loudspeaker manufacturer. I would derate this rating by at least half.
Looks like you've heated up the voice coils of the speakers sufficiently to get the whiff of warm enamel. Fortunately, it appears you've reduced the power in time to avoid permanent damage. Keep on enjoying them, but on music program!
The 75W RMS rating is more likely to apply to an everchanging music signal and, even then, is probably inflated by the loudspeaker manufacturer. I would derate this rating by at least half.
Looks like you've heated up the voice coils of the speakers sufficiently to get the whiff of warm enamel. Fortunately, it appears you've reduced the power in time to avoid permanent damage. Keep on enjoying them, but on music program!
I always like to enjoy super bass heavy music. but I guess this means i have to stick to half their rated power for them to handle it.
they smelled bad for just a few seconds like 2 or 3 then it went away completely.
they smelled bad for just a few seconds like 2 or 3 then it went away completely.
Use Pink Noise. That's what manufacturers do.
It's approximate to music, since it usually covers the whole spectrum.
It's approximate to music, since it usually covers the whole spectrum.
Turn ‘em up until they start to sound bad... then turn ‘em down a little. That’s your maximum power handling level.
I'm not following terrible advice like that!
and I dont have a way to generate pink noise anyways. plus my ears would be dying i'd need hearing protection for that.
My ears would die
and I dont have a way to generate pink noise anyways. plus my ears would be dying i'd need hearing protection for that.
My ears would die
Speakers are damaged when a powerful amp pumps more wattage through a speaker than it can handle, or when an underpowered amp clips when it’s asked to put out more wattage than it easily can. In either case, you should be able to hear it before it does permanent damage... and back off the volume until you don’t hear the distortion anymore.
That’s going to give you a practical idea of how loud you can play your music on your system through your speakers. It won’t give you a number.
The advice to go by the sound is far better advice than seeking to define a power number.
Using a sinewave for power test is asking to smoke the voice coil. The IEC standard for power ratings for loudspeakers uses pink noise with a 6dB crest factor.
The practical limitation on power handling is a function of thermal limits and excursion limits which in turn are heavily affected by the enclosure the driver is in.
Best advice.... use your ear.
Using a sinewave for power test is asking to smoke the voice coil. The IEC standard for power ratings for loudspeakers uses pink noise with a 6dB crest factor.
The practical limitation on power handling is a function of thermal limits and excursion limits which in turn are heavily affected by the enclosure the driver is in.
Best advice.... use your ear.
The unit is good as long as it works. You say these started to smell like burned, so do not perform such tests if you care to keep these alive. I have a rule of thumb that says, the unit has got an ability to withstand continuously 1/10 of the power rating stated by the manufacturer.
(Our US power grid is sine wave) - How hot does a 30 watt soldering pencil get? When the cone's movement is restained there's little movement and little air flow for cooling. I once let some magic smoke from a 3" voice coil doing LF sine testing. (transform eq was "on" but very little useful output)
in free air they already seem to reaching very close to mechanical limits at 30 watts of power going to them. i don't hear any bottoming out or really bad noises but the surround looks a bit stressed and the cone doesnt move very linear/accurately i can tell just by looking at it.
i have given them plenty of break in though for sure. really played them a lot until their FS dropped below 40hz
at first their FS was above 50hz so thats quite an impressive drop in FS. they sound a lot better than fresh out of the box. less muddy and less boomy sounding. more smooth/rich sounding.
i just wish the tweeters had a tiny bit more sparkle to them but that could be just be personal preference and not a fault of the speaker design.
i have given them plenty of break in though for sure. really played them a lot until their FS dropped below 40hz
at first their FS was above 50hz so thats quite an impressive drop in FS. they sound a lot better than fresh out of the box. less muddy and less boomy sounding. more smooth/rich sounding.
i just wish the tweeters had a tiny bit more sparkle to them but that could be just be personal preference and not a fault of the speaker design.
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😱 You can't do that! You WILL burn up the speaker being tested.
You can use tone bursts. Use short bursts followed by long off intervals. Measure fast.
Somewhere on youtube there's all kinds of speaker testing signals.
how come ive seen plenty of speakers and subwoofers take their rated power in real time and more. continuously. playing a test tone for over 5 minutes straight and barely get warm?
are some just too over rated to handle their rated power continously?
are some just too over rated to handle their rated power continously?
You may be interested in this information on testing speaker power handling.
Speaker power handling
It covers pink noise, crest factor and the various testing standards.
Speaker power handling
It covers pink noise, crest factor and the various testing standards.
how come sundown audio and other good speaker/subwoofer manufacturers subwoofers can handle their full rated RMS power running a sine wave of like 30 to 50hz for like 5 minutes straight and even higher than rated power with no problem at all?
nobody in their right mind would test a 12" subwoofer with pink noise! that would also destroy your ears if your within a 100 foot radius of it. they aren't meant to play frequencies above like 100hz at most and pink noise consists mostly of higher frequencies above 100hz for sure. and if the low pass filter is enabled. a lot of the signal is being lost anyways if you were to try to play pink noise into a subwoofer. it would just make a deep irritating rumbling noise and probably blow the subwoofer up.
My 40 watt RMS dayton audio MK402 bookshelf speakers can handle their rated 40W RMS playing a 50hz sine wave all day long with real 40 watts RMS going to them. so that must mean other speakers are either overrated or not rated properly if they cant handle their rated power continuously. isn't that the whole point of an RMS rating. the continuous average power the speaker can handle.
nobody in their right mind would test a 12" subwoofer with pink noise! that would also destroy your ears if your within a 100 foot radius of it. they aren't meant to play frequencies above like 100hz at most and pink noise consists mostly of higher frequencies above 100hz for sure. and if the low pass filter is enabled. a lot of the signal is being lost anyways if you were to try to play pink noise into a subwoofer. it would just make a deep irritating rumbling noise and probably blow the subwoofer up.
My 40 watt RMS dayton audio MK402 bookshelf speakers can handle their rated 40W RMS playing a 50hz sine wave all day long with real 40 watts RMS going to them. so that must mean other speakers are either overrated or not rated properly if they cant handle their rated power continuously. isn't that the whole point of an RMS rating. the continuous average power the speaker can handle.
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Section 2.a. of the article to which I referred mentions pink noise being applied over a bandwidth of one decade.
It suggests that the bandwidth for testing a bass speaker could be 50-500Hz.
Presumably a bandwidth of 10-100Hz would be suitable for a subwoofer.
It suggests that the bandwidth for testing a bass speaker could be 50-500Hz.
Presumably a bandwidth of 10-100Hz would be suitable for a subwoofer.
Perhaps this will help you understand what does happen when you have a power input of 30W ( 10.1Vrms into a dcr=3.4) Driver parameters are made up by myself. It is no problem for a driver to withstand a single sine wave aimed at resonant frequency of the unit in the box, or the one free air.
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