Hi,
When you listen to typical 2 channel setup, regardless speakers size, be it towers or small bookshelf speakers, the low end could be 20Hz-80Hz.
If the smaller speaker cannot play anything lower than 80Hz by design, how would it get damaged?
Or does this only apply to home theater system where you set speakers to Large for full range but speakers can only gown down to 80Hz?
I thought anything below the 80Hz, the speakers just cannot play it due to the crossover cutting off those lower end frequencies?
When you listen to typical 2 channel setup, regardless speakers size, be it towers or small bookshelf speakers, the low end could be 20Hz-80Hz.
If the smaller speaker cannot play anything lower than 80Hz by design, how would it get damaged?
Or does this only apply to home theater system where you set speakers to Large for full range but speakers can only gown down to 80Hz?
I thought anything below the 80Hz, the speakers just cannot play it due to the crossover cutting off those lower end frequencies?
There isn't necessarily a "crossover" (filter) preventing low frequencies from going to a speaker.
As there typically is no crossover to cut out bass but still forcing a small driver to play 30Hz loud, which it cant due to small area and max movement, it will break mechanically or have its (thin) voice coil burned. So yes, LF caused the damage.
"Cannot play" doesn't mean it wont try... and fail.
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"Cannot play" doesn't mean it wont try... and fail.
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In a full range signal, low frequencies are not attenuated. Most passive and a lot of active loudspeakers have no protection against full range and high level. Mainly because the low frequencies cause excessive woofer movements and following failure.
This gets worse when only low frequencies are applied btw, like LFE. That is partly because your ears do not notice the high levels correctly.
This gets worse when only low frequencies are applied btw, like LFE. That is partly because your ears do not notice the high levels correctly.
The damage to speaker with low freq. is at excessive volumes then? If listening to low or moderate levels, it should be ok?
If the speaker is ported, then below tune excursion skyrockets as the driver is effectively unloaded from the enclosure. So if there's no xover, then they can be easily damaged with high level signal below tune.
I had a 10" woofer fail infinite resistance in a KLH23 2 way with a 1 part crossover. I was using a ST70 35 w/ch tube amp. KLH23 had only a small film cap series the tweeter. I sometimes walked across the wood floor with a phono arm on the LP. This could have caused the flexible ribbon in the center of the woofer to rip. The thud of my feet caused LWEIII with visible 10" woofer to bulge out ~1".
In home CD+radio use, there is not much chance of super subsonic frequencies. I've donated the KLH23 with a new Parts-Exp grs-10-8 woofer to a church for the organ. Original Allen speakers had rotted foam surrounds. I have added a mixer between organ generator & power amp, to mix in microphone or electric instruments for live performers. There is a significant risk of a dropped microphone or a RCA cable pulled part way out causing a 100 W blast of 60 hz noise. Because of this, and an annoying 60 hz hum at 1/10 W I can't get rid of, I'm putting a crossover in the speaker to trap 60 hz, and resist anything at 60 hz below with ~12 db rolloff. The organ player never uses the pedals anyway, so no need for 30 hz that the organ could produce.
Organ amp is class AB 100 w @ 4 ohms, +-36 v rails, so possibly 20 v peaks of dangerous low frequencies. Direct coupled no DC protection. Series the woofer will be a 330 uf 50 VNP capacitor. Nichicon UVP1H331MHD. 7 ohms impedance @ 60 hz. Parallel the woofer will be a murata 22 mf 7 ohm coil, series 2 10 ohm 5 w resistors. 27 additional ohms parallel impedance @ 60 hz, 23.5 ohms @ 30 hz, 21 ohms 15 hz. Reason for the resistors, the murata coil is limited to 400 ma. Also 330 uf series 22 mf resonates at 60 hz. The murata coil is $4. Next 20 mf coil up is 18ga at P-E for $50. I didn't see that as necessary to protect a $29 woofer. I will short one of the 10 ohm 5 watt resistors with a 330 ma trip PTC resistor to maximize hum reduction at the 1 watt the organ player uses (17 ohms parallel), but protect the 22 mf coil if a disaster blast of low frequency signal occurs.
In home CD+radio use, there is not much chance of super subsonic frequencies. I've donated the KLH23 with a new Parts-Exp grs-10-8 woofer to a church for the organ. Original Allen speakers had rotted foam surrounds. I have added a mixer between organ generator & power amp, to mix in microphone or electric instruments for live performers. There is a significant risk of a dropped microphone or a RCA cable pulled part way out causing a 100 W blast of 60 hz noise. Because of this, and an annoying 60 hz hum at 1/10 W I can't get rid of, I'm putting a crossover in the speaker to trap 60 hz, and resist anything at 60 hz below with ~12 db rolloff. The organ player never uses the pedals anyway, so no need for 30 hz that the organ could produce.
Organ amp is class AB 100 w @ 4 ohms, +-36 v rails, so possibly 20 v peaks of dangerous low frequencies. Direct coupled no DC protection. Series the woofer will be a 330 uf 50 VNP capacitor. Nichicon UVP1H331MHD. 7 ohms impedance @ 60 hz. Parallel the woofer will be a murata 22 mf 7 ohm coil, series 2 10 ohm 5 w resistors. 27 additional ohms parallel impedance @ 60 hz, 23.5 ohms @ 30 hz, 21 ohms 15 hz. Reason for the resistors, the murata coil is limited to 400 ma. Also 330 uf series 22 mf resonates at 60 hz. The murata coil is $4. Next 20 mf coil up is 18ga at P-E for $50. I didn't see that as necessary to protect a $29 woofer. I will short one of the 10 ohm 5 watt resistors with a 330 ma trip PTC resistor to maximize hum reduction at the 1 watt the organ player uses (17 ohms parallel), but protect the 22 mf coil if a disaster blast of low frequency signal occurs.
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