DIY sites

[getafix]

I've searched this forum and I still can't find any good DIY sites regarding the design of loudspeaker enclosures. Could any of you guys/girls direct me to a site that would help a newbie like me in understanding the intricacies of enclosure design.

[Nappylady]

well, if you hang out here, you'll get earfuls of information from everyone here... Lots of information to be had, though it may take a while to start sinking in.

As far as I know, there aren't really any newb sites for DIY speakers; if you want to learn, your best bet is to get a book. The one I seem to hear about the most is Loudspeaker Design Cookbook, but I don't know anything else about it, as I have never read it or looked it up.

Also, start building simple projects--start with full-range driver projects, or 2-way, or open-baffle, which are easier (IMO) to design and build than more complex designs like 4-way active 18th-order bandpass sub, and 5 of 'em for home theatre... Don't get too ambitious from the get-go. Patience, grasshopper!

Good luck to you, I hope you find all the information you need.

[Nuuk]

If you want an open baffle design with loads of instructions, try THIS

[7V]

Originally posted by getafix
I've searched this forum and I still can't find any good DIY sites regarding the design of loudspeaker enclosures. Could any of you guys/girls direct me to a site that would help a newbie like me in understanding the intricacies of enclosure design.

Start with The Loudspeaker Design Cookbook as has been suggested.

You can try the Madisound forum but I think that this forum (diyAudio.com) is by far the best.

Ask the question and you'll probably get the answer.

Good luck.

[Timn8ter]

Not to be contrary, especially to such knowledgeable fellows but, if the first book I read on loudspeaker design was the Cookbook I may have given up right there. It's very involved and possibly overwhelming to someone just getting started. I usually recommend The Great Sound Stereo Speaker Manual by David Weems to get started. Once you're comfortable with that the Cookbook will be much more enjoyable and understandable.

[7V]

Originally posted by Timn8ter
Not to be contrary, especially to such knowledgeable fellows but, if the first book I read on loudspeaker design was the Cookbook I may have given up right there. It's very involved and possibly overwhelming to someone just getting started.

I think that's a fair point. We forget how long we've been playing this game. I haven't read the David Weems book that you mentioned but I've dug out an older book by the same author and it does seem a little more basic. My version of the Cookbook is from the 80s. I suppose it has moved on a bit since then.

Steve

[Dave Jones]

Originally posted by 7V

Start with The Loudspeaker Design Cookbook as has been suggested.

I can't recommend starting with that book. It's tough going for a complete newbie. I speak from very recent experience. There are far too many terms that he uses without defining, or without defining adequately. It gets very, very frustrating.

For example, on the first page of chapter one, he gives,

Q -- ratio of reactance to resistance (series circuit) or resistance to reactance (parallel circuit)

Qts -- total Q of driver (woofer) at fs, considering all driver resistances

I couldn't figure out what that meant the first time I read it, and if the awful truth be known, I *STILL* don't know what it means. I've now seen enough graphs of low-Q this and high-Q that to have an intuition for what the effect of Q is, but that's about it.

I've read the book three times now, and I still can't understand most of it. Furthermore, the name is deceptive. It's not a cookbook at all. It's more like a sophmore textbook for wannabe cooks. We freshmen can't make heads or tails of it.

[Nappylady]

Q.... *sigh*

I've read tons on Q, and all I know now is this: low Q is GOOD, lower Q is BETTER.

Having built 4 dipole cabinets, I have to say, if I'd had any idea the effect of Q on the final sound quality, I'dve spent the extra $50 per driver to get lower-Q woofers. For dipoles, this is a must. Forget what anyone says about using Q as a crude EQ--just turn up the "bass" knob on your reciever!

Getting into this esoteric and complicated subject is very hard for noobs, and I'm frankly amazed I got as far as I did without burning out, like I do on all my other major goals.

Good luck to everyone anyway, and I hope we can, over time, flatten the learning curve some...

[navin]

Q is not that hard guys. first break it up into electrical and mech.

the mech part simulates a spring. high school spring physics would give you a good idea. remember those expriments eith small weights at the end of the spring? the srpin in this case is the spider, surround etc...

electrical Q is a matter of an electromagnetic ckt with a coil in ca mag gap. this is a little more diffcult to understand as once cannot "see" the operation. one has to visualise it. it is like equating a mech equation like F=ma to a electrical one like P=VI.

before i hijack the thread i think there are sites out there that deal with both springs and compliance and electromagnetiism that can offer detailed explanations.

[7V]

Originally posted by navin
Q is not that hard guys. first break it up into electrical and mech.

the mech part simulates a spring. high school spring physics would give you a good idea. remember those experiments with small weights at the end of the spring? the spring in this case is the spider, surround etc...

electrical Q is a matter of an electromagnetic ckt with a coil in ca mag gap. this is a little more diffcult to understand as once cannot "see" the operation. one has to visualise it. it is like equating a mech equation like F=ma to a electrical one like P=VI.

I think this is what they mean, navin and also what I meant when I said that we have forgotten how long we have been playing this game.

Do your paragraphs above explain Q to complete newbies?
The mech paragraph doesn't link Q with the spring. For instance, what happens if a spring has low Q or high Q?

The electrical paragraph is even more obscure to a beginner.

Also, many people were totally turned off high school physics at school. I suspect that many would-be speaker designers need to relearn the basics of high school physics.

I don't say this as a criticism and I don't say that I could do any better myself. Just that it's not easy describing these concepts so that beginners can understand them.

Can anyone else come up with a simpler explanation of Q or expand on navin's version?