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Just bought GWIII 50" but im new to speakers and im trying to build a HT but i think i should understand the basics first.


Can you explain to me what are these things i should know like... Whats hz and ohms and watts and db and their relation to each other and receivers? whats crossover? whats too little, whats overkill, whats standard levels for this equipment? stuff like this.


I dont want to get ripped off at the store.


please answer some of this the best you can

OR please point me to a place/forum/site to get good information on basics


go easy on me


thanks
 

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OY! You don't know what you're asking. I don't know if this will help but I'll try to at least give you a start, and hopefully other, more knowledgeable folks can be more specific, and possibly steer you to a tutorial that will do a better job of this than I can.


Hz. stands for Hertz (Hertzian waves), named after the guy who discovered (?) them, and they are what we old folk used to call "cycles per second." Sound is vibration. When I speak, my vocal cords vibrate, which causes the air to vibrate, and when that vibrating air reaches your ears it causes your ear drums to vibrate, and you 'hear" me.


But different sounds vibrate at different rates. Low sound vibrate slowly, say 20 to 200 vibrations (or "cycles," or "Hertz," or Hz.) per second. Actually 20 Hz. is about the lowest sound we humans can "hear." Mid range sounds vibrate at faster rates, say 200 to 5000 Hz., and High sounds vibrate really fast, say 5000 to 20,000 Hz. (20,000 Hz. being about the highest sound we humans can "hear") Don't hold me to those exact ranges, but you get the idea.


You may have noticed that many speakers (meaning the entire wooden box or structure), have 2 or more drivers (meaning each of those round things that make the sounds) in them. Each of those drivers is responsible for reproducing a given range of the sound spectrum. In a "3 way" speaker (a speaker with 3 drivers); the little round driver (usually at the top, and called a "tweeter" because a bird tweet is a high frequency sound, and would be heard coming from that driver) reproduces the "highs," the slightly larger driver (usually in the middle, and called the "mid") reproduces the "mids" (middle range frequencies), and the larger driver (usually called the "woofer," because a dog's "woof" would be a low frequency, and would be heard coming from that driver) reproduces the low frequencies.


Watts and ohms are closely related to each other


A watt is a measure of power and an ohm is a measure of resistance. Receivers (or amplifiers) are rated in watts which indicate how much "power" they have. Speakers are rated in ohms, usually 4, 6, or 8 ohms, and that represents how much resistance they offer to a receiver's power.


If you'll forgive an oversimplification, the higher the resistance, the more power you need. You may have noticed that a receiver's power rating is given in relationship to a speakers resistance. It'll be something like "100 Watts per channel into 8 ohms." That means if you hook up speakers rated at 8 ohms of resistance to that receiver, the receiver is capable of putting 100 watts of power into those speakers. The lower the number of ohms, the lower the resistance. That same receiver. rated at 100 watts into 8 ohms, is capable of putting out more watts of power into a 4 ohm speaker. That's why, when buying a receiver, you should have a reasonable idea of the resistance of the speakers you want to buy. You want to be sure you have enough power to adequately drive your speakers. More speaker damage is caused by an underpowered receiver being driven to hard, than by an overpowered receiver.


Going back to that "3 way" speaker, with the 3 separate drivers, now. When you stop to think about it, you run just one wire from the receiver to the speaker, and that one wire is carrying all the frequencies (highs, mids and low) together. How does the sound get separated into 3 parts (highs, mids, and lows), and then get sent to the appropriate drivers? Enter the crossover (or crossover network). The sound comes into the speaker on that one wire and goes to this little "thingy" (don't you love it when I use those technical terms) that does the job of separating the sound and routing it to the appropriate driver. That "thingy" is the crossover. Speakers aren't the only piece of equipment with crossovers. Receivers can have them too. Sub-woofers have them too. Well, since a sub-woofer is a speaker, that makes sense.


db stands for decibels, which is a measure of loudness. 110 db is VERY loud, 40 db is relatively soft. Somewhere on the internet you can find a chart that shows what the various levels relate to. Like, "110 db is how loud a jachammer is 3 feet away," or something like that.


I hope this helps to some degree. Maybe someone can provide you with better, more understandable info than I've just provided.


Don't be in hurry with this. You're about to spend a LOT of money, so take your time to learn about this before you jump. Move too quickly; repent slowly. Try to find an enthusiast in your area who can help. This is a very complicated subject. I've been working with sound for more than 30 years, and I'm STILL a layman, STILL learning, StILL confused, and STILL making mistakes.
 

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Glad to be of service. Nice TV set, by the way.


Here's a helpful article from Axiom Audio.

http://www.axiomaudio.com/10thingsam.html?1250


I'm a fan of Axiom speakers, but that doesn't mean they would be right for you. There are a lot of highly rated speakers out there. The trick is to find ones that pleases you.


You will find that a lot of manufacturers web sites such as Axiom (speakers), Ascend (speakers), HSU (sub-woofers), SVS (sub-woofers), etc. have forums or message boards like AVSForum. They are worth perusing. And, just like AVSForum, it's a wise practice to take what you read with a grain of salt. What you get on any forum is a lot of conflicting opinions and a variety of opposing facts, which may, or may not be correct. Read a lot, and look for a consensus of opinions and facts. That will help you sort fact from fiction.


I found the article at this web page which just happens to list a ton of articles you might find helpful.

http://www.ecoustics.com/Home/Home_T...eater_Articles


Keep learning. If you need, you can send me a personal message (pm) by pressing the "pm" button at the top of one of my posts, and I'll try to respond as best I can.


Good luck.
 

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You may also want to check out some Home Theater Basics at this website from Aperion Audio who makes great sounding speakers for a great price:

http://www.aperionaudio.com/basics/ba_index.html


You may want to try the direct online purchase route from the manufacturers themselves. This could save you the trouble of haggling and getting burned by sleazy salesmen. Also, these direct merchants are very helpful and they do sell quality products.
 

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Rijax,

That was a great post. It is really nice to see that people care and want to help new folks like me to get the most knowlege possible. Thank you very much for your time.
 

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Quote:
Originally posted by Rijax
OY! (20,000 Hz. being about the highest sound we humans can "hear") Don't hold me to those exact ranges, but you get the idea.

Rijax - I have read a lot of posts here. A lot of people have asked for info in "layman's" terms, but I think yours is the first post I have read. Great job - it should be a sticky for newbies!!!!


Of course, I just had to do some more research, and I came across this little tidbit:


"The pitch of a note is described by its frequency. Frequency is measured in hertz (Hz), or cycles per second. The general range of hearing for young people is 20 Hz to 20kHz. The upper frequency limit decrease with age, and so the older a person gets, the less well they can hear high notes. Also, the male hearing range decreases more quickly than the female, and so women can generally hear higher pitch notes than men of similar age."


The link to this info is here: http://www.npl.co.uk/npl/publication...coustics5.html


in case anyone wants to look it up. This makes a lot of sense, how many times have you seen young children hold their hands to their ears in a loud environment. The female comment also makes perfect sense - how many times does the wife ask you to "turn it down"?
 
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