how does a sub play more than one sound

[nauc 10+ year member]

like a bass drum beat and a bass guitar riff

someone showed me a pic of the sound waves, basically the drum sound waves on top of the bass guitar sound waves or vice versa

but if you did that, say a 40hz tone and a 60hz tone and laid the waves over one another, wouldnt that cause a 3rd sound, like a 90hz tone or something

bet i lost you //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

Click to read more...

 

[revrider1 5,000+ posts]

Yes you did????

 

[Fast1one 10+ year member]

I have no idea how to answer your question...but I understand what your asking....

 

[nauc 10+ year member]

Yes you did????

if the sub is creating the bass drum sound and the bass guitar sound, theres gonna be a time when the bass drum and the bass guitar are making sounds at the same time

and if you looked at the sound waves on a scope, you wont just see the bass drum sound waves, youll see the bass guitar sound waves too, one on top of another

but

if that happens, why doesnt it create a higher tone, since the more waves there are, the higher the pitch, the more the sub moves

 

[jaycross 10+ year member]

i get what ur sayin...... i just dont know the answer lol

 

[mtdewelf 10+ year member]

magic,

 

[nauc 10+ year member]

like in this picture

say the black line is the bass drum sound waves and the red line is the bass guitar sound waves

if the sub moves out every peak, why doesnt it sound like a higher fq because the sub will be moving a lot more than if was just creating the bass drum waves or the bass guitar waves

 

[wilzyx 5,000+ posts]

squeak should now, hopefully he chimes in

 

[helotaxi 5,000+ posts]

Sounds of different freqs don't sum in the way that you seem to think that they do. 30hz + 60hz = 30hz and 60hz not 90hz.

Notice that the various sine waves don't align but every few cycles (and that's only for harmonics or partial harmonics). At the points where they align, even partially, there is constructive interference and at the point where they are out of phase there is destructive interference. The resulting sound is what is known as a beat frequency. What it sounds like is an increase and decrease of the louder of the two original sounds with the rate that the volume changes being the beat frequency. If you want an example of what it would sound like with basically plain sine waves set two noisy fans next to each other running at different speeds with both of them pointed at you. The rising and falling droning sound you hear it what I'm talking about.

Music is never a pure sine wave though. No instrument will produce one. I creates the fundamental freq and then several harmonics (multiples of the fundamental). The number and relative volume of the harmonics are what add texture to the sound and give an instument its characteristic sound. What this looks like in the o-scope is the basic shape of the the fundamental freq with ripples in it representing the harmonics. The sub gets this as a signal and the large movement is at the freq of the fundamental. For the reproduction of the harmonics, the position of the sub while playing the fundamental can be seen as the rest position and the movement goes from there.

 

[Fast1one 10+ year member]

^^^Great response...

 

[yacob.naif 10+ year member]

i've often wondered the same thing

especially with midrange drivers and tweeters, since they're usually producing TONS of different frequencies at once

i've always (and will continue to) tried not to think about it

 

[CBFryman2 5,000+ posts]

And you cant hear anything less than 7 beats...IE 7Hz seperation. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

As far as how the sub moves? Look at the wave of a song...it is very jumpy and eratic, not like a sine wave. Constructive and destructive "interference" in the reording is what makes some songs have 20db+ crest factors. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[CBFryman2 5,000+ posts]

Oh and read up on what exactly doppler distortion is, most of the papers on the net will explain how the speaker playes multiple frequincies at once.

 

[GordonW 10+ year member]

Sounds of different freqs don't sum in the way that you seem to think that they do. 30hz + 60hz = 30hz and 60hz not 90hz.
Notice that the various sine waves don't align but every few cycles (and that's only for harmonics or partial harmonics). At the points where they align, even partially, there is constructive interference and at the point where they are out of phase there is destructive interference. The resulting sound is what is known as a beat frequency. What it sounds like is an increase and decrease of the louder of the two original sounds with the rate that the volume changes being the beat frequency. If you want an example of what it would sound like with basically plain sine waves set two noisy fans next to each other running at different speeds with both of them pointed at you. The rising and falling droning sound you hear it what I'm talking about.

Music is never a pure sine wave though. No instrument will produce one. I creates the fundamental freq and then several harmonics (multiples of the fundamental). The number and relative volume of the harmonics are what add texture to the sound and give an instument its characteristic sound. What this looks like in the o-scope is the basic shape of the the fundamental freq with ripples in it representing the harmonics. The sub gets this as a signal and the large movement is at the freq of the fundamental. For the reproduction of the harmonics, the position of the sub while playing the fundamental can be seen as the rest position and the movement goes from there.

The absolutely CORRECT answer. //content.invisioncic.com/y282845/emoticons/thumbsup.gif.3287b36ca96645a13a43aff531f37f02.gif

Regards,

Gordon.

 

[nauc 10+ year member]

Here's a visual of what Squeak is describing ... In this case, it's a 30 Hz tone and a 300 Hz tone ...

As you can see, the 300 Hz tone plays "on top" of the 30 Hz tone ...

got it, thanks...........