Home Forums DIY Speakers and Subwoofers DIY Speaker Project – the correct order!?

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    deadeye
    Member

    Hi all

    I’ve been researching DIY speakers for about 10 days as I want to see if I can build something better than my PMC OB1s.  So forgive the dumb questions at this stage.

    I’ve rightly or wrongly already designed and started to prototype the cabinets and it’s time to choose drivers so I can start calculating internal box sizes and port legnths etc.

    I’ve downloaded all the software I seem to need but there are two issues.  Obtaining FRD and ZMA files vs choosing drivers.

    I’m leaning towards Morel as their tweeters seems to handle a lot of power and they seem to have a naturally nice flat curve.  But it appears to model the tweeters with some drivers, I need to buy them first and create my own files.  But then isn’t it better to model them when they’re in the box they are goin got be installed in?

    My project isn’t about building the cheapest speakers, it about building something myself that sounds (to me I guess) better at higher volumes than my PMCs.

    For eaxmple, this is the tweeter I’m considering: https://www.morelhifi.com/product/st-1108/

    They come in a matched pair which I like.

    I’ve emailed Morel about the FRD and ZMA files but no response.

    So:

    a) Can someone point me in the right direction to obtain the files for Morel’s later speakers so I can plug them into XSim and PCD

    or…

    b) Do have to buy them, measure them myself and risk wasting a serious amount of cash.

    or…

    c) Can Morel be trusted in that their Frequency response chart is perfect and I should just buy them!?

     

    Thanks in advance.

    DIY Speaker Project – the correct order!?

  • DIY Speaker Project – the correct order!?

  • tvor-ceasar

    Moderator
    February 11, 2021 at 12:37 pm

    I can’t speak to Morel’s customer support and willingness to supply data, but if they have graphs available showing the Frequency response and impedance, you can use a graph tracer to create the FRD and ZMA files. There’s a thread a while back where a few are recomended, all you need to do is a forum search. IIRC, “FPGraph tracer” would probably be a term that would take you right there. While not the absolute best way to get the info, it’s good enough to get started to see if you’d at least consider the drivers.


    DIY Speaker Project – the correct order!?

  • deadeye

    Member
    February 11, 2021 at 4:28 pm
    Posted by: @tvor-ceasar

    I can’t speak to Morel’s customer support and willingness to supply data, but if they have graphs available showing the Frequency response and impedance, you can use a graph tracer to create the FRD and ZMA files. There’s a thread a while back where a few are recomended, all you need to do is a forum search. IIRC, “FPGraph tracer” would probably be a term that would take you right there. While not the absolute best way to get the info, it’s good enough to get started to see if you’d at least consider the drivers.

    I have done this but the graphs on their datasheets are very poor quality which makes this difficult.

    I wonder if this is deliberate!?

  • tvor-ceasar

    Moderator
    February 11, 2021 at 5:44 pm

    @deadeye

    You would think that if a manu is selling a driver, they’d want to give you high enough quality information to entice you to buy their products. ¯_(ツ)_/¯

    Now that you are above 5 posts, you should be able to share links. If you would go back to your original post and update the link there, we can look at it to see what’s going on. 


  • deadeye

    Member
    February 12, 2021 at 3:39 pm

    I’ve updated the link.

    I’ve actually been able to model the tweeter pretty well and it’s amazingly easy design a high-pass for it although I suppose I’d like to not atteniate the whole thing and left the > 15khz where it is.

  • 123toid

    Administrator
    February 15, 2021 at 8:05 am

    @tvor-ceasar

    You would think that.  But it also is where there is some misleading information due to this. But what can you do?  That is why I like to look for drivers that zoom in on the graph.