why are are woofers bigger than tweeters?

Road Runner

This might sound pretty naive, but I'm wondering why woofers are bigger than tweeters. I mean, the thing that determines the pitch is how fast the driver moves back and forth, so if a big driver moves back and forth at the same rate that a little driver does, then the sound should have the same frequency. It seems like the distance between two regions of compressed air in a note made by a big driver would be the same for a little driver because the same amount of time that went by between the driver moving all the way to the front and to the back would be the same. It seems that the bigger driver would just make a bigger soundstage and maybe would be louder from a distance. It's probably different for a vibrating object like a tympani where its pitch depends on its size because it's vibrating, but the driver isn't vibrating - it's just moving back and forth because of the electricity it's being given. So.......it seems like all drivers should be the same size and some should just be given different frequencies, but obviously that's not the best way to do it.

treitz3

Tweeters have a faster frequency than that of a lower range woofer. Not as much movement necessary to perform the function, simply put.

VR3

Yep, but you need displacement for your lower frequencies...

A tweeter would probally have to move a good 4 ft to produce bass...

treitz3

Midrange, if that. lol

Early B.

Super simple answer -- you need space to produce bass.

Here's how you can think about it -- imagine two farts -- one is a wimpy high pitched vegetarian girly **** with hardly any smell. Your hole barely opens up to let it out. Let's call that one a "tweeter ****." Now imagine a huge sulfur smelling "Barry White after a night at the Mexican buffet" ****. Your hole opens up pretty big for that one because there's lots of force behind it. Let's call it a "woofer ****."

So do you understand what I'm sayin'?

Road Runner

Vr3MxStyler2k3 wrote: »

Yep, but you need displacement for your lower frequencies...

A tweeter would probally have to move a good 4 ft to produce bass...

I guess that's another thing I don't get. I figured that displacement just determined how loud the sound was and how fast the driver moved back and forth determined how high or low the sound was. So it seems that if a tweeter moved back and forth relatively slowly it could make a low-pitched sound.

Road Runner

Early B. wrote: »

Super simple answer -- you need space to produce bass.

Here's how you can think about it -- imagine two farts -- one is a wimpy high pitched vegetarian girly **** with hardly any smell. Your hole barely opens up to let it out. Let's call that one a "tweeter ****." Now imagine a huge sulfur smelling "Barry White after a night at the Mexican buffet" ****. Your hole opens up pretty big for that one because there's lots of force behind it. Let's call it a "woofer ****."

So do you understand what I'm sayin'?

I can't even smell what you're smellin'.

treitz3

Early B. wrote: »

Here's how you can think about it -- imagine two farts -- one is a wimpy high pitched vegetarian girly **** with hardly any smell. Your hole barely opens up to let it out. Let's call that one a "tweeter ****." Now imagine a huge sulfur smelling "Barry White after a night at the Mexican buffet" ****. Your hole opens up pretty big for that one because there's lots of force behind it. Let's call it a "woofer ****."

OMG, too funny!!

Read between the lines man. There's humor there but it gets the point across.

Early B.

Road Runner wrote: »

I guess that's another thing I don't get. I figured that displacement just determined how loud the sound was and how fast the driver moved back and forth determined how high or low the sound was. So it seems that if a tweeter moved back and forth relatively slowly it could make a low-pitched sound.

Form follows function.

treitz3

http://en.wikipedia.org/wiki/Frequency

Roadrunner, take a look at this. Follow the links if you do not understand but don't get to in depth or you will never learn if you try to divulge it all tonight. When you read the fundamentals, then read EarlyB's post. Then you will see the humor.

Fongolio

Early B. wrote: »

Super simple answer -- you need space to produce bass.

Here's how you can think about it -- imagine two farts -- one is a wimpy high pitched vegetarian girly **** with hardly any smell. Your hole barely opens up to let it out. Let's call that one a "tweeter ****." Now imagine a huge sulfur smelling "Barry White after a night at the Mexican buffet" ****. Your hole opens up pretty big for that one because there's lots of force behind it. Let's call it a "woofer ****."

So do you understand what I'm sayin'?

That is the by far the funniest explanation of science I've ever heard. Long live Barry and long live the Mexican buffet.Thanks for making me laugh out loud.

wallstreet

Hey, if you can see a tweeter vibrate, you got some good eyes.

Fongolio

Sound travels in waves. Sound waves are measured in hertz. How much treble or bass a sound has is a function hertz. One hertz equals one cycle per second. 5 hertz equals 5 cycles per second. The fewer the hertz in sound the bassier the perceived sound. More hertz equals more cycles per second equals more treble. The average human hears down to about 20 hertz (hz) and to 20,000 hz at the high end. Full range speakers can span this range. Very low bass (20 hz) and very high treble (20 khz). In order to to perceive bass at the very low end a lot of air must be moved because the sound waves are spaced very widely apart. This is why sub placement in a room or car is important and why good subs have a 180 degree phase switch. If the widely spaced waves reflect off a surface and bounce back we may hear the first non reflected wave and the reflected wave cancel each other to some degree and the result is very subdued bass. To correct this sometimes changing the phase switch 180 degrees will make the waves arrive in better time and get more accurate fuller sounding bass. At the other end of the spectrum high treble is produced with with very high hertz (cycles per second). A large speaker is less capable of cycling fast enough to produce the highest trebles. Thus a smaller more capable speaker. High treble waves are spaced very close together and in a cone type speaker tend to beam the waves. So speaker placement is important in order to be "in the beam". The very tight spacing of the waves make the perceived volume louder and thus more volume from a smaller speaker. I have two 12' Alpine type R subs in my car along with two 5 X 7's and two 6 x 9's. If I turn up the volume to what most people consider really loud with the subs pounding and then turn off the 5x7's and the 6x9's and let only the subs play it doesn't sound nearly as loud and most people are amazed that the subs on their own don't produce huge volume.....except because of the subs wide spaced waves the sound travels through the body of the car and easily through walls and someone in a house nearby would complain about how loud my car is even though I can easily carry on conversation with just the subs on. I hope this helps and all Polkinators please correct (I know you will) any wrong science or glaring errors I have made.

RuSsMaN

C is for Cookie, that's good enough for me.
C is for Cookie, that's good enough for me.
C is for Cookie, that's good enough for me.

Oh Cookie Cookie Cookie starts with C.

Road Runner

Fongolio wrote: »

In order to to perceive bass at the very low end a lot of air must be moved because the sound waves are spaced very widely apart.

Well, it seems like with earbuds you can get low bass without moving a lot of air and those are really small drivers, but the bass doesn't really have that deep rich quality and maybe the driver actually is large compared to the space between it and the eardrum, but I still don't get the connection between low pitch and moving more air because low pitch just seems to be fewer cycles per second and moving more air seems to be more about spatial distribution than pitch. If it's just the fact that lower frequencies cancel each other out more than higher ones that sort of makes sense to me, but I don't really see how moving more air solves that problem because it seems the lower frequencies would still interfere with each other the same way. That may be the reason why a woofer should always be in an enclosure: the opposite waves will cancel each out because they have a lower frequency and they have to be contained in a box.

Early B.

RR -- you're over analyzing this issue. Give it up. We've already explained it in the simplest of terms. If you still don't understand, there's nothing more we can do.

Road Runner

Early B. wrote: »

RR -- you're over analyzing this issue. Give it up. We've already explained it in the simplest of terms. If you still don't understand, there's nothing more we can do.

Now that I've thought about what Fongolio wrote, I think what he said makes sense and I think I understand it. No thanks to you.

BottomFeeder

Early B. wrote: »

Super simple answer -- you need space to produce bass.

Here's how you can think about it -- imagine two farts -- one is a wimpy high pitched vegetarian girly **** with hardly any smell. Your hole barely opens up to let it out. Let's call that one a "tweeter ****." Now imagine a huge sulfur smelling "Barry White after a night at the Mexican buffet" ****. Your hole opens up pretty big for that one because there's lots of force behind it. Let's call it a "woofer ****."

So do you understand what I'm sayin'?

Oh my gosh! I understand! I understand! Could you please arrange to answer all of my audio related questions in **** terms? I could learn so much faster!

ShinAce

Actually, the main reason is directionality(or directivity).

A big woofer can be made to produce nearly every frequency, but the higher you go, the more the sound travels like a spotlight instead of a floodlight.

So, you make a smaller driver to pick up the higher frequencies and cross them over.

Likewise, a small driver can play low frequencies, but will not be loud enough to do the job.

reeltrouble1

RuSsMaN wrote: »

C is for Cookie, that's good enough for me.
C is for Cookie, that's good enough for me.
C is for Cookie, that's good enough for me.

Oh Cookie Cookie Cookie starts with C.

hehehehe AND D is for the Dingus with the crumbled cookie

phuz

Road Runner wrote: »

Well, it seems like with earbuds you can get low bass without moving a lot of air and those are really small drivers

True, but you have to jam the earbuds in your ear to hear the bass.

A normal tweeter in a normal speaker is not capable of moving enough air to create low bass frequencies that are audible at any distance. To move enough air to hear bass freqs - at say 3m - you need a driver capable of enough excursion to move enough air to reach your ears at a given distance at the freqs desired.

tcrossma

a Trumpet vs. a Tuba. You can get a trumpet to go low, or a tuba to go high, but it takes a lot more effort and the results aren't nearly as good.

Early B.

Why are y'all still responding to this question? If the OP doesn't understand the **** analogy, it's utterly hopeless.

Road Runner

phuz wrote: »

True, but you have to jam the earbuds in your ear to hear the bass.

A normal tweeter in a normal speaker is not capable of moving enough air to create low bass frequencies that are audible at any distance. To move enough air to hear bass freqs - at say 3m - you need a driver capable of enough excursion to move enough air to reach your ears at a given distance at the freqs desired.

That might be why when someone's listening on their Ipod really loud, for someone at a distance there's no bass and almost no midrange to be heard. Only the highs can be heard. It's different when there's a party down the street and only the bass can be heard. I imagine that would be because walls and other things absorb the highs more than the lows.

Road Runner

Early B. wrote: »

Why are y'all still responding to this question? If the OP doesn't understand the **** analogy, it's utterly hopeless.

The **** analogy just doesn't smell right.

phuz

Road Runner wrote: »

The **** analogy just doesn't smell right.

Try some different pants.

Early B.

Road Runner wrote: »

The **** analogy just doesn't smell right.

:D:D

You're right. I certainly wouldn't want to stroll into the trajectory of a Barry White ****, especially now that he's no longer alive!:eek:

treitz3

Road Runner wrote:

I imagine that would be because walls and other things absorb the highs more than the lows.

You are correct. My neighbor would beg to differ though.