Loudspeaker design in general *novice*

[bob_bsme]

Hi, my name is Hallvard and i'm new here..
i have a few general questions regarding loudspeaker design.

a few friends and myself have been toying with the idea of building our own speakers..
bookshelf monitors actually, à la b&w's cm1.

i've been searching the web for a while now looking for ideas on where to start..

i realize i should probably get a hold of some literature..
i'm looking at vance dickason's cookbook but i'm wondering if there are more in-depth alternatives out there?


this is probably very basic, but what is the recomended design sequence when starting from scratch?

from what i've gather, i need to select the type of speaker, the drivers, the crossovers and finally the enclosure?


i'm also wondering if anyone could tell me what the ideal internal space in an enclosure looks like?

a sphear? tube? cube?

thanks
Hallvard

[JinMTVT]

i'm also wondering if anyone could tell me what the ideal internal space in an enclosure looks like?

a sphear? tube? cube?

thanks
Hallvard

the perfect interior of an encloser is no interior at all





Just wanted to say HI and Welcome

[joe carrow]

For your very first speakers, I suggest building a design that somebody else has already established. There are hundreds of them out there, and dozens of good ones. There are a lot of good websites that will answer many of your questions.

Here's a link to the DIY Website thread in this forum:

DIY web pages

here are some of my favorite places to read about projects, driver testing, and speaker design theory:

http://zaphaudio.com/

http://linkwitzlab.com/

http://www.humblehomemadehifi.com/

http://www.silcom.com/~aludwig/

http://mfk-projects.com/

http://htguide.com/forum/forumdisplay.php4?f=39

http://quarter-wave.com/

http://sound.westhost.com/

After reading these sites, you may still want to design your own from scratch. It's possible that one of these sites contains a design that will meet and exceed your needs- then you just need to build it.

Also, you asked what the idea internal space in an enclosure looks like. In my opinion, it's a tube. B&W makes extensive use of terminated tapered tubes to absorb rear radiation on their speakers, most notably on their flagship speaker.

[Richard Ellis]

You do have a starting point already as you have seemed to have put a general limit on the size of the enclosure.
Now... their is a old-school dimension of the "ideal" box shape, it is refered to as the Acoustic ratio..it is a height to width to length ratio (Can't find the book at this moment) whereby the internal waves inside the box will not pile-up...will not reflect inside in such a fashion as to reflect back and strike the cone to vibrate it.
There is a lot of debate as to the type of "stuffing" that one puts inside...from cotton to wool to fibreglass...etc. Stuffing makes the shape consideration less critical however.
The other wild card is will it be an acoustic suspension design or will it be a ported design?
What are you expecting these speakers to do for you? What type of music do you listen to? How loud to you play music? How much power (Watts) to you have at your disposal?
Lotsa things to consider...narrow things down & you'll find your choices will narrow too.
__________________________________Rick...........

[Klimon]

For the internal dimensions, google 'golden ratio loudspeaker' Keep in mind that unparallel sides will be better and that all in all the internal shape of the speaker is not an issue on most speakerdesigners 'things to worry about'- list, there are other aspects of bigger importance.

Here's some very interesting reading about loudspeaker-schools and history: http://www.nutshellhifi.com/library/...r-design1.html

And a site about the benefits of sphere-shaped speakers for the external diffraction and smooth baffle step: http://www.usenclosure.com/diffracti...ion-graphs.htm

Simon

[sreten]

Hi,

http://www.zaphaudio.com/audio-speaker12.html

or something smaller ?

http://www.humblehomemadehifi.com/HATT-III.html

/sreten.

[demogorgon]

Hei Hallvard!

Now, as sreten allready said, zaph audio is geniouse.

http://www.zaphaudio.com/

i havent encountered any online projects that documents so thoroughly or are so no-nonsense as his, a bigbig+ in my book. that guy know his stuff

http://www.zaphaudio.com/ZD5.html
his scan speak\vifa system.
i cant say i think theres much better options out there for bookshelfes.

as for literature, i do belive www.eltek.no has a pdf of a loudspeaker cookbook out in norwegian thats rather good. i printed it out in school a few years back, and its stilla invaluble source of information for me.

good luck mate
-Marius