Behavior of Woofers at and around tuning.

[SpeakerBoy 64]

Hi guys, i am writing a paper about the behavior of woofers tied in with resonance, tuning and such, the behavior of a woofer under stress (i.e. during use) and a detailed diagram of all the parts of the average woofer.

i am focusing on these main topics:

A) resonance/tuning

1) movement at and around the tuning frequency

2) the uses and benefits of diferent tunings, uses; musical and competitions

B) Behavior under stress

1) impedance rise

2) thermal compression

3) box rise + the effect of tuning on it

C) mechanical parts

1) Moving parts

2) suspension/soft parts, and effects of different styles of suspension materials

3) cooling technologies

Thanks for taking the time to read this, If anything needs to be clarified, let me know.

Edited November 11, 2009 by DeepSubBoy

[topgun 262]

*edit* not needed

[SpeakerBoy 64]

Do you have a real question to ask? If not this thread is getting locked...

sorry did you only see "hi" ? i accidentally hit enter while typing, my bad.

[topgun 262]

What class is this for?

The reason I ask is because these topics aren't quite something that can be summed up well in a paragraph.

[slim2fattycake 85]

I doubt you're going to be able to answer all those questions in your paper. That shit goes in depth with physics and electrical/acoustical studies. But yeah, what class is this?

[SpeakerBoy 64]

What class is this for?

The reason I ask is because these topics aren't quite something that can be summed up well in a paragraph.

Just a research paper on a topic of your choice.

I don't need to go super detailed, more of a basic explanation, for the average joe. My teachers wouldnt know the difference anyway

I just want to write a basic explanation of each, as i do understand how crazy complicated it can get. In laymans terms, i would like to write up the effects of these properties on a speaker, each one individually. Gotta do the whole notecards thing, so i thought i would try and make it easier by including it in one thread (as opposed to 10 different ones).

[slim2fattycake 85]

http://bcae1.com/

some info can be taken from there.

[BKOLFO4 29]

You need to just go buy "The Loud Speaker Design Cookbook" by Vance Dickason

[SpeakerBoy 64]

You need to just go buy "The Loud Speaker Design Cookbook" by Vance Dickason

Where could i buy that? And how much $?

[todd.brust 29]

It's about 40 bucks, but you will find tons of good factual information.

http://www.amazon.com/Loudspeaker-Design-Cookbook-Vance-Dickason/dp/1882580478/ref=sr_1_1?ie=UTF8&s=books&qid=1257976188&sr=8-1

On of the better books to have on hand when you want to know anything about speakers and how they work in different situations(enclosure, crossovers, etc.)

You can answer most if not all from this book.

[SpeakerBoy 64]

It's about 40 bucks, but you will find tons of good factual information.

http://www.amazon.co...57976188&sr=8-1

On of the better books to have on hand when you want to know anything about speakers and how they work in different situations(enclosure, crossovers, etc.)

You can answer most if not all from this book.

Sweet, I think i'll pick it up around my birthday..... 12 days

[SpeakerBoy 64]

It's about 40 bucks, but you will find tons of good factual information.

http://www.amazon.co...57976188&sr=8-1

On of the better books to have on hand when you want to know anything about speakers and how they work in different situations(enclosure, crossovers, etc.)

You can answer most if not all from this book.

Sweet, I think i'll pick it up around my birthday..... 12 days

Ordering the book soon,

Could someone throw me a quick idea of what the woofer does at tuning? why does it move less, but produce the same, if not more sound? I understand it a little, but i don't know how to say it quite right.

Thanks,

Chris

[BKOLFO4 29]

http://en.wikibooks.org/wiki/Acoustics/Bass-Reflex_Enclosure_Design

"This forms a Helmholtz resonator (click here for more information). Physically, the port functions as the “neck” of the resonator and the enclosure functions as the “cavity.” In this case, the resonator is driven from the piston directly on the cavity instead of the typical Helmholtz case where it is driven at the “neck.” However, the same resonant behavior still occurs at the enclosure resonance frequency, fB. At this frequency, the impedance seen by the loudspeaker diaphragm is large (see Figure 3 below). Thus, the load on the loudspeaker reduces the velocity flowing through its mechanical parameters, causing an anti-resonance condition where the displacement of the diaphragm is a minimum. Instead, the majority of the volume velocity is actually emitted by the port itself instead of the loudspeaker. When this impedance is reflected to the electrical circuit, it is proportional to 1 / Z, thus a minimum in the impedance seen by the voice coil is small. Figure 3 shows a plot of the impedance seen at the terminals of the loudspeaker. In this example, fB was found to be about 40 Hz, which corresponds to the null in the voice-coil impedance."

[TechSys 3]

^^ What he said.

I've got the loudspeaker cookbook. When I started studying it I was pretty much overwhelmed by it. Lots of info and yes, you could get all your questions answered out of it. There are a couple other books that you could still get info from, but I can't remember the names.