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therobby3
12-17-2007, 12:54 PM
I am getting a woofer with a frequency response of 25hz to 2khz. I was wondering if I HAVE to use a crossover. I realize that if I don't the higher pitched sounds won't be produced, anything over 2khz. So if I don't use one but still have higher frequencies above 2khz running to that woofer is that a bad thing for the woofer? I don't care if it doesn't produce the sounds, just if it is damaging.

mlsstl
12-17-2007, 01:44 PM
You will not damage a woofer by not using a crossover. If you had enough high frequency energy to fry the woofer without a crossover, it would also damage a midrange or tweeter.

The primary problem with not using a crossover with a woofer is that it will continue putting out some higher frequency energy. This will interfere with the midrange or tweeter and degrade the sound quality. The purpose of a crossover is to better manage the transition between drivers. (And it also provides protection to the midrange or tweeter which do need to be prevented from attempting the large diaphragm excursions that lower frequencies demand.)

These are general rules. There are many different theories regarding crossover design, however, "protecting" the woofer from higher frequencies is rarely one of them.

therobby3
12-17-2007, 01:58 PM
Ok, thanks you alot. I still need to get the tweeter too. I was wondering another thing with tweeters. The output of the amplifier is 500 watts, and the woofer I am using is a 2500 watt, so that's not the problem it can handle it. But when I'm looking for a tweeter, do I still have to look for a tweeter over 500 watts? Or do tweeter not take the full wattage, so would a 200 watt tweeter be ok then?

mlsstl
12-17-2007, 02:40 PM
Power specifications can be very misleading. An amp's output wattage can range from a RMS or "continuous" spec rated from 20 Hz to 20 KHz, to some very mystical "peak" ratings that would generate much larger numbers. Same thing with drivers. The amount of power a driver will accept will vary with frequency and duration and other factors.

I don't have any idea the basis on which your equipment was rated so I can't help.

Generally speaking, though, tweeters will not handle as much power as a woofer. If it is a cone/dome driver, the tweeter voice coils are much smaller and thus overheat more easily. (They need to be smaller and lower mass in order to respond to the higher frequencies.)

If you are building a speaker system, there are a lot of parameters to consider and juggle. In your case, it sounds like you may be going for sheer loudness. How loud do you listen to your music? How efficient are the drivers you are using? What type of bass cabinet will be used (sealed, ported, horn loaded, etc?)

As you can see, things get very technical, very fast, and the comments above barely scratch the surface. However, step one is to lay out your goals for the speaker. What do you want it to do? After you've settled that question, choose a design and components that support those goals.

Good luck!

N. Abstentia
12-17-2007, 06:29 PM
A 2500 watt woofer? mmmmmkay......

:nonod:

therobby3
12-18-2007, 05:08 AM
Hmm.. Thank you.. Well let's see. Yes, loudness is probably my main objective, mainly bass. Perfect quality isn't my number one priority but that doesn't mean I want it to sound like crud. The was thinking about using a horn type tweeter, probably not a cone oned. As for the woofer, I was probably going to go with a ported box for it. From what I read, sealed cabinets don't sound quite as loud, but they are able to hits the notes better and more exact, as compared to ported cabinets which hit a little louder, allow more excursion (possibly too much?) but don't hit as presicely. Is that correct? With that in mind I was wondering how important it is where the port is made on the box? Does it change depending on the woofer you are using and manufacturer? Thanks again.

mlsstl
12-18-2007, 09:07 AM
Sounds like you are relatively new to the hobby of building speakers from scratch. This is a complex subject with a lot of variables. I'd recommend you spend some time learning the basics of driver evaluation and cabinet design. There are some very good web sites that go from the basics all the way to some very sophisticated material. Try a Google search for "diy speaker design." For drivers, cabinets, parts and complete kits, you also might try www.parts-express.com. Might be easier than reinventing the wheel yourself.

therobby3
12-18-2007, 12:36 PM
Yes I am new to the hobby and have been trying to read up on alot, but I guess there's alot to learn. But thanks, I'll check it out.

bfalls
12-18-2007, 01:01 PM
Parts Express is a good site. You might try this one as well.
http://sound.westhost.com/

Many good articles and DIY projects. Mlsstl is correct, there are many parameters to consider building a speaker from scratch. There are a lot of good kits which make it easier. This is also a good one. I built a high-end subwoofer with parts from this site.

http://www.audioc.com/

basite
12-18-2007, 02:27 PM
A 2500 watt woofer? mmmmmkay......

:nonod:


yeah

I was wondering that too...

I wonder if it would survive 500 watt pure power already...

bfalls
12-19-2007, 06:01 AM
A 2500 watt woofer? mmmmmkay......

:nonod:
The Sunfire True Subwoofer has a 2700W internal amp and capable of 116db peak SPL.

therobby3
12-19-2007, 07:30 AM
Yea, it's 2500 watt's max, and 1500rms. It's an 18" technical pro. Is that to unbelievable?