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Recording sound

  1. Jun 27, 2005 #1

    I'm aiming to create a device (as small as possible), powered by a battery, that will allow me to record one single sound, and then play that sound back when a button is pressed.

    It's been about 15 years since I took physics in high school, and I've no idea where to start.

    Any help (links?) would be greatly appreciated :)

  2. jcsd
  3. Jun 27, 2005 #2


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    If it's not a complex sound, such as a spoken word, it might be easier to just synthesize it rather than record it. Do you want to be able to change it at will? Is the button to be remote, or part of the package? More details would be helpful. You can get very small digital memo recorders quite cheaply now.
  4. Jun 27, 2005 #3

    One spoken word is my aim. The ability to change it would be nice, but I think it would be better to keep it simple (for now). The button would be part of the package.

    Height is the dimension I am most concerned about. The width and length of the total package could be 5-10 centimeters each, but the height would need to be as small as possible.
  5. Jun 27, 2005 #4


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    Sounds like a practical joke in the making. :biggrin:
    I don't have time or resources right now (have to go to work in a few minutes), but I'll snoop around later and see what's available.
  6. Jun 27, 2005 #5
    Actually, it's for gaming purposes :)
  7. Jun 27, 2005 #6
    so you would be looking for a IC that can take the output from a microphone , digitize it and play it back..
  8. Jun 29, 2005 #7
    If you only need to record spoken words, you have simplified your problem immensely.

    The human voice to be comprehensible only needs a range of between 1Khz and about 5Khz. You don't need superfast slew rates or hi-fidelity microphones.

    The main component can dual as both a microphone and a speaker: Use a piezo-electric disk (found in almost any hobby/electronic supply co.) as both. If you want added quality of recorded sound you can use a second pressure-crystal as is found in acoustic guitar pickups that snaps onto the wood of an instrument.

    Interestingly, you could look at talking dolls to see what they are using these days. I would'nt be surprised to find a pre-made IC chip that does everything and only needs a battery connector and a piezo-pickup and housing designed to work as a mini-speaker cabinet.
  9. Jun 29, 2005 #8


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    These already exist, and you can buy them in greeting cards. You press a button, say a message, and then the card's recipient can play it back. Don't bother trying to make your own.

    - Warren
  10. Jun 29, 2005 #9
    Good idea (greeting cards). Found some for $3.99.

    These Voice Pads might do the trick as well. Found some for $7.99.

    I bet they both use the same kind of system, so I'll try the cheaper greeting card system first and see if it'll work for me.
    Last edited: Jun 29, 2005
  11. Jul 1, 2005 #10


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    Well that's just too cool! The only talking cards ever sold in my town are pre-recorded. Never even heard of recordable ones or the pad things. They're probably available in the city, but I don't go there much.
  12. Jul 2, 2005 #11
    p.s. if you're not satisfied with the bass response of greeting-card kits try gluing one to a small wood box or shoebox. Use a stiff glue like epoxy.
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