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Audio/Video DIYaudio, Parts Express, Madisound, any audiophiles out there?

  1. Oct 28, 2013 #1
    What goes through an Engineer's mind upon designing a loudspeaker? Surely there must be some general guidelines, no? Perhaps. Although this is most likely dependent upon the circumstances (cost, enclosure, available power, etc).

    If these guidelines do exist, what are they. If you could order them, how would you go about doing it?

    I need to design a loudspeaker around these circumstances:

    Cost: FREE
    Frequency Response: 20hz-20khz
    Enclosure: Infinite Baffle (is it baffle or baffled?)
    Available Power: .5 RMS

    Okay, so this is a bit unrealistic. A full range driver capable of playing the whole spectrum? I'm not sure if that exists. Why IB? This speaker will be for a demonstration, so no enclosure! The .5 wrms is from the LM386. I'll just drive it with my Ipod.

    Okay! So I need a loudspeaker with great sensitivity. Wait though, I thought sensitivity was how loud a drive could play without audible distortion (vaguely speaking). When people say "I need a driver that's really sensitive," does that mean they need one that's like 90db+ or a speaker rated at like 5wrms?

    I'll stop here. I have no idea how large to make the cone, what angle should it have, what material to make it out of, etc. I assume that last part is up to the individual's taste (I prefer paper!). Btw, I have no idea why cone material affects the sound. I just see sound as a vibration of a medium. Regardless of how they're pushed & pulled, atoms are atoms, right? I have no idea how many turns I need, what AWG to use, the size of the voice coil. I have no idea what magnet to use, & what type (neo or that other one). I don't know whether I need a dust cap or not. I'm not sure how large to make the pole piece (or vent if you will).

    ^& why stop at the geometry of the cone in relation to the desired frequency response? You don't want a 40oz magnet with a 2" cone. ...lol, a ratio of a ratio.

    Maybe I should just start with whatever kind of relation I need between the voice coil & the magnet?

    I'm lost!


    *It seems to me that there are a LOT of give & takes when it comes to designing loudspeakers. For instance, you don't always need a 15" cone to get 30hz. Enclosure type plays a role here. I know there are 5" drivers capable of 30hz in the correct enclosure (like transmission line).
    Last edited: Oct 28, 2013
  2. jcsd
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