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1Hz on a normal speaker?

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zimble01
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Hello all

I have a small program, Audacity, which can generate very low frequencies such as 1Hz. I am curious, but much too scared to try playing such a frequency on my system. Would this damage an ordinary speaker at all (ie. one whose response is technically upwards of 43Hz, such as mine)?

Hmmm...

Ashley James
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Re: 1Hz on a normal speaker?

I doubt it would do any harm, but you'll probably not see or hear anything because there will be a filter in your amplifier below about 5 Hz at least to make sure you don't put DC through the speakers, which will damage them.

A typical 6.5" Bass driver's output starts to reduce at a little over 100 Hz and goes on getting quieter as the frequency lowers. How much bass it produces is dictated by it's size alone and it's ability to pump air. Because you're listening in a room you'll find that some lower frequencies sound louder and others quieter or sometimes not audible at all and when you move your speakers around, you change these nodes. Because your ears are not very discerning in this region, you're usually able to get what sounds pretty good to you. The bottom end varies from room to room, so two people with the same speakers may get get completely different results - You need to remember this when reading reviews.

Ash

zimble01
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Re: 1Hz on a normal speaker?

Thank you, Mr. James, for your reply. The thing is, a friend of mine told me he had played a ridiculously low frequency through his Hi-Fi system (not a mini-hi-fi -- a system), and had seen the cones moving at 1Hz. I understand your point about direct current into speakers, and 1Hz being very close thereto might have damaged the loudspeakers. I apologise if I am harping on pointlessly, but this has made me very curious.

Ashley James
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Re: 1Hz on a normal speaker?

It's possible that he did, but usually designers put filters in at about 5 Hz to prevent the amp outputting DC.

These lower frequencies don't usually harm speakers until clipping occurs, but where it can be done is playing high frequency sine waves through tweeters. They may not appear very loud but they might damage them, so it's OK to do a sweep but best not to sit on one frequency.

Ash