What driver specs to prioritize for nearfield listening?

Discussion in 'Computer Audio' started by viivo, Nov 12, 2017.

  1. viivo

    viivo Gawd

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    I'd like to build a pair of basic powered bookshelf speakers for PC use, but I know many drivers are not made for nearfield listening. What should I look for when shopping for the drivers? Also I'd love to be able to use one of PE's pre-built crossovers - would they work or is a different design needed for this application?
     
  2. B00nie

    B00nie [H]ardness Supreme

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    It's not as simple as just choosing drivers. You have to look at the finished product as whole and design it around your needs. If you're going passive you'll have big challenges adjusting the impedance and crossover tuning to get proper results. Active is way superior as you can use 24db/oct linkwitz-riley and often also DSP features. And have the benefit of not having to handle multiple driver impedances with your crossover.

    You should choose your drivers so that their directivity fields are about equal at your crossover frequency (the side radiation is matched at frequency).
     
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  3. westrock2000

    westrock2000 [H]ardForum Junkie

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    You could do all that stuff, but you would have to buy a calibrated measuring microphone as well as software to use the mic to measure response, the Dayton kit is good (I have that) or you can use REW (have used it, but prefer the Dayton suite for ease of use). And by measuring and using MiniDSP you can get the response just perfect. You also get the advantage of driver each with it's own amplifier channel because the crossover is being done at line level.

    But.....

    You aren't going to notice if you don't go that route. You can use a proven design, and get results that will sound just fine. Usually near field necessitates a bookshelf (don't see people using towers in near field very often). You can look at PE's pre-designed kits. The Overnight Sensation is popular, but the bass is going to be weak. The TriTrix has more bass, but is larger. These kits come with pre-made enclosures. Is that ideal, or were you planning on building the enclosure as well?

    But that is just the passive part. Do you already have something for the amplification, or will that need to be considered in the project as well?

    And I assume you are using "near field" in the more colloquial meaning of a desktop application and not in terms of commercial mastering application?
     
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  4. B00nie

    B00nie [H]ardness Supreme

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    A coaxial driver is the easyest to get to work in near field. In near field the distance between the tweeter and the bass becomes a concern (polar patterns become bad in vertical axis) so if you can find a kit speaker based on let's say Seas T18REX/ACG in a closed box https://www.hifitalo.fi/uploads/files/products/aw7[1].pdf it's going to work better than average in near field.
     
  5. Rifter0876

    Rifter0876 n00bie

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  6. cageymaru

    cageymaru [H]ard|News

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    Oh you like Parts Express already. They have lots of information on speaker building in their forums. Click the Resources link on their page at the top right.

    Tech Talk is the place to go for the Parts Express forums. Really good information in there and guides like this.
    http://techtalk.parts-express.com/forum/tech-talk-forum/38661-the-speaker-building-bible

    Project Gallery is a collection of various projects that users have submitted. I love looking at stuff that other people are doing even if I never try it. Some people are truly talented!
    http://projectgallery.parts-express.com/

    I would like to go active like everyone was suggesting earlier. MiniDSP seems like a worthy investment as others have mentioned. For $100 you get active crossovers and time alignment so you can tweak all year long without having to buy new parts. ;) $100 is close enough to the price of assembled crossover that I'd go with that. Maybe one of the guys here can explain the difference in features of the $200 version and the $100 version as I have only read about them but never used one.
    https://www.parts-express.com/brand/minidsp/646
     
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  7. B00nie

    B00nie [H]ardness Supreme

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    MiniDSP requires two amps though so it's going to be more expensive than a passive crossover.

    99% of cases a ready designed kit is the way to go with DIY. A successful self build requires a proper measurement device and a huge study in practical theory.
     
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  8. IdiotInCharge

    IdiotInCharge Not the Idiot YOU are Looking for

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    'Build'

    If you want to experiment, awesome. If you want to just get great nearfield sound, grab a pair of JBL DSR 305's and call it done :D.
     
  9. B00nie

    B00nie [H]ardness Supreme

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    The 305:s are great in near field but aren't so suitable in far field. Their performance degrades a lot outside nearfield.
     
  10. IdiotInCharge

    IdiotInCharge Not the Idiot YOU are Looking for

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    Sure! And good to point out, as they're not necessarily 'universal', which I may have implied with 'call it done'. However, for the nearfield purpose of the OP, I bet they'll surprise :).
     
  11. N4CR

    N4CR 2[H]4U

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    PMPO is critical.


    /s

    Boonie knows his shit. I nearly started a sub manufacturing company and would not DIY loudspeakers for all the reasons he lists and more. Put a year of study in and you might do an acceptable job from scratch..
     
  12. viivo

    viivo Gawd

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    Thanks for the replies. I think I will go with one of PE's bookshelf kits. I've only ordered sub kits from them in the past, but I can't see speakers being much more difficult to assemble unless extremely precise soldering is required.
     
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  13. B00nie

    B00nie [H]ardness Supreme

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    I don't know how much those PE kits cost but you probably could skip the building part and match the price by purchasing a pair of Pioneer BS-22-LR:s or the Elac debut B5:s.

    Those two speakers are built by a world renown designer Andrew Jones and probably are far better than the PE set.