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codra-callsign
12-03-2005, 08:49 AM
I was wondering if anyone could help answer some questions for me? I am wanting to build a nice set of speakers but i dnt know what any of the specs mean? :confused: i do understand the frequency part though. What would be better to use 8 ohm speakers or 16 ohm speakers? if anyone can help thanks!!

markw
12-03-2005, 09:42 AM
I was wondering if anyone could help answer some questions for me? I am wanting to build a nice set of speakers but i dnt know what any of the specs mean? :confused: i do understand the frequency part though. What would be better to use 8 ohm speakers or 16 ohm speakers? if anyone can help thanks!!That's like saying you know what a nail is and now you want some help designing and building a house.

Try reading a few books on the subject or hanging out in the DIY forums at www.madisound.com before jumping into the water.

Bertter yet, pick up a kit from www.partsexpress.com.

Florian
12-03-2005, 09:52 AM
Yup, speaker building is a LOT more compley then that. You can write GoneFishin, he has build his own horn speakers!

Flo

N. Abstentia
12-03-2005, 10:44 AM
Just curious..why are you wanting to build your own speakers? I mean it's not just something you wake up one morning and decide to do, is cost a concern? Are you just wanting to learn?

Florian
12-03-2005, 11:20 AM
A never ending amount of knowledge and legends are in here

http://www.diyaudio.com/

codra-callsign
12-03-2005, 11:21 AM
Just curious..why are you wanting to build your own speakers? I mean it's not just something you wake up one morning and decide to do, is cost a concern? Are you just wanting to learn?



well see im starting to get into the electronics study. and yes i would like to learn but i thank it would be a cool project. plus the speakers i have now are blown and crapy.

N. Abstentia
12-03-2005, 01:35 PM
Well that's cool, you gotta start somewhere. I was lucky and worked at a stereo shop through high school and college so I had the luxury of being able to tear stuff apart to see what made it tick. I also had a full woodworking shop (and luckily the skills) at my disposal. The toughest thing to learn is probably crossover design. A simple crossover is not that hard, but to do it right is something that takes some time.

So I'm gonna agree with markw, start out with a Parts Express kit and build/modify/upgrade from there.

codra-callsign
12-03-2005, 01:56 PM
Well that's cool, you gotta start somewhere. I was lucky and worked at a stereo shop through high school and college so I had the luxury of being able to tear stuff apart to see what made it tick. I also had a full woodworking shop (and luckily the skills) at my disposal. The toughest thing to learn is probably crossover design. A simple crossover is not that hard, but to do it right is something that takes some time.

So I'm gonna agree with markw, start out with a Parts Express kit and build/modify/upgrade from there.


ok i might just do that thanks for the help

hifitommy
12-03-2005, 04:02 PM
http://www.madisound.com/

for a lot of what you need.

Lensman
12-04-2005, 09:14 AM
Building speakers is not as straightforward as many initially think. First, it requires combining woodwooking skills with basic electronics. This, of course, means you must also have access to the tools and workspace needed for each. Then you'll have to choose from a vast array of drivers, material characteristics, crossover designs, enclosure types, etc. to create your speaker project. You'll also have to realize that the combination of parts and the box you choose will change the rated characterisics of the individual components and be prepared to compensate. Add to this the fact that while great strides have been made in sound theory and mathematics in the last couple of decades, not everything is known about the hows and whys of sound reproduction. Though extensive and detailed, there simply is no comprehensive set of formulas for creating absolutely perfect speakers - at any level or any price. Plus none of the science takes into account the fact that individuals perceive sound differently. Speaker building formulas also can't tell you exactly how speaker designs will actually react to the acoustics in the room you place them in.

The result is that speaker building is as much an art as a science and your ears will have to be the final determining factor in whether a creation is pleasing or not. Where one might find the highs produced by a set of speakers to be pleasing, extended and full of air, another will find them bright, harsh and fatiguing, and still another may think they're too laid-back and lifeless. All of which are reasons there are so many different companies building so many different types of speakers at virtually every price point and why audiophiles will always insist that buying professionally produced speakers must start with auditioning them - regardless of how impeccable the company's reputation. This is also the inherent danger in building speakers from someone else's DIY plans - they may look great on paper and sound excellent to your friends, but not to you.

If you're not deterred any by this, then speaker building can be a fascinating and tremendously rewarding hobby. But is it truly this hard? It can be if you're wanting to do it because you have a discerning ear, a drive for perfection, and a relentess desire to understand as much as possible about the field of sound reproduction. Those who have been bitten buy the bug will tell you there's no thrill quite like researching, desgning, constructing and tweaking a design and having the end result come out right. If you're not so critical, just want some fun, and have a desire to take pride in something you made with your own two hands, building a kit can be just as rewarding and much simpler. It all depends on your level of expectations so I didn't want you to start with a false set of impressions of the complexities of the hobby.

As others have stated, there's some basic theory you should know before you begin - even if you're just wanting to choose a kit to build. In addition to the other links, I'd recommend getting a copy of the Great Sound Stereo Speaker Manual by David Weems. It's a bit dated and you'll probably want to look elsewhere for DIY projects. But the book provides a great introduction into the hobby for those who need to start with the basics. You can also check out the Loudspeaker Design Selection Guide here:

http://ldsg.snippets.org/idx.php3#S1

I'd recommend beginning with Appendix A

The website for Paradigm loudspeakers also has a section that provides a very simple overview of some of the audio terminlogy you'll find DIYer's using when talking about the overall sound qualities of their designs:

http://www.paradigm.ca/Website/AllAboutSound/Compare.html

Finally, I'd recommend you check your phone book for high-end audio dealers in your area. Then take some CDs of music you're very familiar with and go listen to some different designs and hear what all the things you've read about really sound like.

Even if you ultimately decide not to build anything, the knowledge you'll learn from your pursuit will give you a much better understanding of sound reproduction and forever enhance your ability to choose speakers to maximize your listening pleasure.

codra-callsign
12-05-2005, 06:55 PM
Lensman,

Your response was quite in-depth and informative. I will take your suggestions to heart. My father (an industrial electrician) and I are interested in learning not only about building speakers but the electronic theory and mathematics behind it. I figure that through out a project like this I would develop a thorough basic understanding of the electronic principles, devices, and theory. Not only is this project an educational endeavor, but it also would produce some satisfaction in knowing that I had built the speaker system by my self from scratch. The purpose of my post here was an attempt to seek reference from all of you as to recommendations of texts books, web sites, or other sources that I could acquire the basic and developing knowledge of this area that I hope to peruse. My father works extensively with PLC’s. I thought that basic speaker building would start me in the right direction. Thank you for you’re input again and I will continue to monitor and post this site.
:D

codra-callsign
12-05-2005, 07:15 PM
I do have a question. I have read and I think I understand "inductive reactance" and "capacitive reactance". I do not understand "Impedence". I have several speakers that I have gathered. Most of them say 8 ohm. Is this the impedence. I took an ohm meter and checked the coil. It actually read 8 ohms. Where does the impedence ohms come in?

Lensman
12-07-2005, 09:39 PM
I do have a question. I have read and I think I understand "inductive reactance" and "capacitive reactance". I do not understand "Impedence". I have several speakers that I have gathered. Most of them say 8 ohm. Is this the impedence. I took an ohm meter and checked the coil. It actually read 8 ohms. Where does the impedence ohms come in?

The impedance tells you how much current will flow through a speaker. A speaker's impedance is affected electrically by resistance, inductance and capacitance. It's also affected mechanically by the driver's stiffness, mass and damping. So not only will the way you wire up a driver affect the impedance, the type of enclosure you put it in and even by the type of room you place the speaker in will affect the impedance value.

The impedance rating you see printed on the driver is referred to as the nominal impedance and reflects the area the driver will stay in throughout most of the audio bandwidth. In reality, the actual impedance varies with frequency and may range from 4 or 5 ohms to over 50. When you measure the DC resistance across the voice coil of a bare driver, you'll get an ohm value that's the lower impedance bound of the driver. This is typically an ohm or two short of the nominal impedance. Measuring the nominal impedance more accurately requires the use of a signal generator or test CD.

Impedance is important for matching speakers up with the amplification they need. A lower impedance driver will accept more power from a receiver or amplifier. But a low impedance places more stress on a receiver or amp by requiring it to put out more current. If the amplifier can't put out the current demanded it can compress the audio, clip, or even destroy the speakers. On the other hand, impedance that's too high restricts the flow of current needed by the speaker to play at requested volume levels.

For the vast majority of audio equipment, nominal impedance ratings in the 6-8 Ohm range represent a good compromise between current and voltage flow while higher end audio can operate comfortably in the 4 ohm range. Higher end amplifiers can double their available power as the impedance reduces by half.