Need help designing a speaker box

Discussion in 'Audio Visual' started by Constructacon, Oct 3, 2018.

  1. Constructacon

    Constructacon Member

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    I managed to acquire some 6.5" splits (see attached image) a number of years ago from Jaycar when they were discontinued and they have sat on the shelf until now. I'm looking to make a small bluetooth boombox out of them using a cheap Chinese amp and a battery pack. I know there are a million box design programs if you have the TS parameters of the speakers, but alas they don't come in the box, nor were they listed in the catalogue at the time (I found an old PDF copy). Bluetooth audio and not ultra high end speakers mean I'm not needing this to be absolutely perfectly designed, but I want to give it a good shot.

    Does anyone know a rough box size that is suitable to a 6.5" driver? Would I be better making it sealed (easier) or ported (designed for what frequency?????).
     

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  2. oculi

    oculi Member

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    sealed, make it as big as you can without being silly.
     
  3. OP
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    Constructacon

    Constructacon Member

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    Thanks. That will be the challenge I think: keeping it as small as possible.
     
  4. neRok

    neRok Member

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    There's a fair bit of info on the wayback machine, but the page for these particular speakers has no more info, see: https://web.archive.org/web/20091028090959/http://www.jaycar.com.au/productview.asp?ID=CS2338

    There's also a bunch of similar but different 6-ish inch kevlar speakers they were selling at that time, so you can't just presume the specs for a random one will be the same. Have you tried opening the box and seeing if the speaker has a code/mark indicating the specific model it is?

    You can use the "filter results" box at the following link to try find more products: https://web.archive.org/web/*/https://www.jaycar.com.au/productView.asp*
     
  5. sebbyreddan

    sebbyreddan Member

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    https://trueaudio.com/win_abt1.htm

    Edit....Not Free only trial version. ($40usd for full Version)

    Try this...a few years I was all keen to make a DIY sub, using Bass Box for the design, but the one above seems to have all the relevant features, for loudspeakers as well.
     
    Last edited: Oct 4, 2018
  6. samus

    samus Member

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    http://www.scan-speak.dk/datasheet/archive/18w-16531g1.pdf

    This is a datasheet for a similar driver, you could probably use that it it would be fine.

    Those speaks though are designed for a car door, and will work on a plate, with infinite baffle. if you want to go ultimate ghetto mod, just a single 18mm sheet of MDF will work with 4 holes cut out of it.

    If you want to make a small bluetooth boombox, note that they need a few watts being 89db/W sensitivity. Consider making something with about 30 litres (each) of internal volume, and pad the crap out of it to make it seem bigger. Consider feeding them at least 30W RMS each.
     
  7. Ratzz

    Ratzz Member

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    Does this help you? I'd enlarge the speaker enclosures to 6 litres or so for your speakers. Sometimes simple is best.

    Just a sealed box, any dimensions, of about 6 litres in volume with some polyester fibre fill from Spotlight. I guess it really depends on how audiophile you want to go. I'm pretty happy with the sound of these.. listen to the video with headphones for best effect, obviously a sound demo is only as good as the speakers/headphones you are playing it with.

    https://forums.overclockers.com.au/posts/18003009/
     
    Last edited: Oct 4, 2018
  8. gdjacobs

    gdjacobs Member

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    Any Thiele Small data for the drivers? There's lots of tools to predict frequency response for sealed/ported/bandpass enclosures.
     
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  9. OP
    OP
    Constructacon

    Constructacon Member

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    30L each? That's quite a bit larger than what I'd consider portable. That's public address territory there.

    Alas no. Not in the box, nor online. No one seems to have been able to find any, so I'm just doing to do a generic box and hope for the best. I'm now trying to work out what a "generic box" actually is.
     
  10. Bold Eagle

    Bold Eagle Member

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  11. gdjacobs

    gdjacobs Member

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    That's a bit of a pain. If you want to roll up your sleeves, you could measure them (plus Vas). If you don't have much instrumentation, you could use a PC with a decent sound card for measurement and signal generation.
    http://sound.whsites.net/tsp.htm
     
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  12. Sarsippius

    Sarsippius Member

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    I was going to do something like this but as samus mentioned car speakers aren't necessarily good for this sort of application as they're made for unsealed car doors. I went another direction but it probably still sounds pretty good. The video also has a link to his instructable page

     

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