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How to choose an amplifier for dummies?

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  #16  
Old 05-05-2004, 11:51 AM
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Re: How to choose an amplifier for dummies?

Yes, clipping is just one form of distortion. You could also have something like an engine whine that's a form of distortion but not related to clipping. It's easier to explain clipping with a visual. Here's a normal sound wave



It's a normal, smoothly osciallating shape that the speaker will ride to play back.

Now, if I crank up the volume beyond what the amp can handle, it stops being able to push power at its extremity. The peak of the wave gets "clipped off", and you end up with something that looks like this:



And that's not good for your speakers to try and reproduce!


 
  #17  
Old 05-05-2004, 12:04 PM
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Re: How to choose an amplifier for dummies?

Interesting... so what about the opposite where I am pushing out more than my speaker can handle? Is there a noticeable difference in sound between that and clipping? Or will any quality speaker make me deaf long before it reaches its max?

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  #18  
Old 05-05-2004, 12:15 PM
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Re: How to choose an amplifier for dummies?

If the amp's being pushed beyond its capacity, then you'll get clipping. You'll hear it, though. It's not a pretty sound.

As long as you're getting good sound you're probably not hurting anything.

 
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Old 05-05-2004, 12:16 PM
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Re: How to choose an amplifier for dummies?

I concede. I apologize for the mistake in the wattage/db part. I looked it up myself after I opened my mouth (so to speak). Also I should have been clearer on if the impedance actually changes or is "seen" as half by the amp's bridged channel. Peace.

 
  #20  
Old 05-05-2004, 12:16 PM
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Re: How to choose an amplifier for dummies?

I concede. I apologize for the mistake in the wattage/db part. I looked it up myself after I opened my mouth (so to speak). Also I should have been clearer on if the impedance actually changes or is "seen" as half by the amp's bridged channel. Peace.

 
  #21  
Old 05-06-2004, 09:40 AM
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Re: How to choose an amplifier for dummies?

He's right, I'm an RF engineer and we deal with db all the time.

3db doubles power
10db = 10x the power

That's the quick way to measure dbi antenna gain.

46 dbi, is

original power x 10 x 10 x 10 x 10 x 2 x 2

 
  #22  
Old 05-06-2004, 09:44 AM
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Re: How to choose an amplifier for dummies?

RF Engineer? No kidding. Same here... who do you work for?

Drop me a PM sometime.

 
  #23  
Old 05-06-2004, 08:51 PM
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Re: How to choose an amplifier for dummies?

OK, let me see if I have this down.

4 channel amp to power two 6.5 and two 6x9. The 6.5s are RMS 75w @ 4ohm. The 6x9s are RMS 110w @ 4 ohm. So if I want to overpower, I need a 4 x 120 watt amp?

The 10" sub is RMS 400w @ 2 or 8 ohms. For the sub, I need a mono 420w x 1 @ 2ohm amp?

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  #24  
Old 05-06-2004, 10:51 PM
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Re: How to choose an amplifier for dummies?

It really depends on how loud you like your music. What you've suggested should, in my opinion, be more than adequate. Especially regarding the power for the sub--unless you are into loud, bass-pounding music, or just like to really "crank it".

I have about 300 watts going to my sub, I have the gain turned way down on its amp, and I have <u>tons</u> of bass. (IMO)

The more watts the amps push, the more they're going to cost. If you have the $$, what you've suggested is awesome. If you want to save a little, you could probably drop the specs on the front amp, and drop the sub amp down to 250-350 watts.

I think you ought to find a store, listen to some speakers, tell the salesperson you're going to buy a bunch of product, and play "let's make a deal." They should cut you a deal given what you're suggesting you'd buy. (Friends don't let friends pay retail.)

 
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