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some vocab

Discussion in 'Amps and Cabs [BG]' started by MCR, Mar 6, 2004.


  1. can anyone please tell me what a tweeter and an horn are??? what about an attenuator??
     
  2. nonsqtr

    nonsqtr The emperor has no clothes!

    Aug 29, 2003
    Burbank CA USA
    Hi MCR. A tweeter is a speaker that handles (only) high frequencies. It's the opposite of a "woofer", which handles (only) low frequencies. Inside the speaker cab, there's usually an electronic gadget called a "crossover", that divides the signal into high frequency and low frequency components. It takes the unified input signal that comes in on the speaker cable, and splits it up into high frequency and low frequency components. The highs feed the tweeter, and the lows feed the woofer.

    Tweeters are usually (physically) small. Many of them are only an inch or two in diameter, as distinct from the woofers which are usually "big" (12 or 15 inches, or whatever). The "horn" is an attachment that fits on the end of the tweeter, and it's kind of the audio equivalent of a "waveguide". It guides the high frequencies so they "disperse" better out into the audience. You could say that a horn "focuses" the high frequency output from the tweeter.

    There are also "midrange horns" (you can find these on a lot of high end audio speakers, like the Klipsch's often have midrange horns). In general, the higher the frequency, the smaller the speaker, so tweeter horns may be very small, perhaps a couple of inches across, while midrange horns tend to be bigger (maybe 6 or 8 inches across). If you have a three way speaker (with woofer, midrange, and tweeter), then your crossover will have three outputs instead of two.

    The crossover is usually a pretty simple electronic circuit, consisting mainly of coils and capacitors. Basically they're "filters" in the audio sense, so the low pass filter feeds the woofer, and the high pass filter feeds the tweeter, and so on. There are also "electronic crossovers", that you can use "before" the power amp, instead of "after" it. This arrangement might be found in "bi-amp" systems. If you use an electronic crossover, you'll need two power amps, one for the low frequencies and one for the high frequencies. Some bass amps, like the GK 800rB, have both power amps built into the same box, so what you do is use two separate speaker cables, one feeding the woofer and the other feeding the tweeter. Bi-amps are most useful (IMO) when you're using subwoofers. In that case, you can set your electronic crossover to around 80-100 Hz, and use a big gigantic power amp to drive your subs. But bi-amps are also useful in other situations, for instance if you have an 18" speaker cab and a 4x10 speaker cab, you can run the lows through the 18 and the mids and highs through the 4x10. Generally, the lower frequencies need more power, so for instance in the GK 800rB, there's a 300 watt amp for the low frequencies and a 100 watt amp for the high frequencies.

    An "attenuator" (also sometimes called a "pad") is basically just a volume control. You use it to adjust the "amount" of high frequencies, relative to the low frequencies. Typically these are found in speaker cabs that have a built-in tweeter (like the SWR Son of Bertha, for instance, has a 15" woofer and a small tweeter, and there's an "attenuator" on the back that adjusts the volume of the tweeter). You just dial up the tweeter volume that sounds best to your ear.
     
  3. thanks a lot that really helped
     
  4. ojthesimpson

    ojthesimpson

    Jul 21, 2003
    Draper, UT
    K now my turn. I know was GAS means persay but I don't know what G A S stands for?
     
  5. Lockout

    Lockout

    Dec 24, 2002
    Illinois
    It stands for Gear Acquisition Syndrome. :)