Home Forums DIY Speakers and Subwoofers My first DIY speaker project Reply To: RE: My first DIY speaker project

  • deadeye

    Member
    November 5, 2021 at 10:16 am

    So… I finished them but it was a rocky road.

    This was the 2nd main prototype

    [IMG]http://development.crm-uk.com/images/speakers/beforecrack.png[/IMG]

    The 3rd which was to match split very quickly and badly – I hadn’t completely covered the outside so the MDF shrank – I think it was 10mm shorter than the one above!

    [IMG]http://development.crm-uk.com/images/speakers/split1.jpg[/IMG]
    [IMG]http://development.crm-uk.com/images/speakers/split2.jpg[/IMG]
    [IMG]http://development.crm-uk.com/images/speakers/split3.jpg[/IMG]

    Gutted

    Eventually, the 2nd started to split too – when I took the drivers out, the inside must have dried out and shrunk.

    [IMG]http://development.crm-uk.com/images/speakers/crack.jpg[/IMG]

    I’m all in at this stage, I’ve spent about £1000 on drivers and about £400 on crossover parts.

    I went back to the guy I’d found to CNC the slices for me and he suggested moisture resistant MDF.

    So I did 4 things (which is never great when diagnosing a problem):

    1) Used MR MDF
    2) Left every slice to acclimate in my living room for 2 weeks.
    3) Sprayed Shellac-based primer inside and out of every slice (64 in each speaker)
    4) Built each speaker in sections

    However, I used the threaded rod again and clamped all the sections together to bodywork the whole speaker in one go.

    [IMG]http://development.crm-uk.com/images/speakers/sandingbeforesplitting.jpg[/IMG]

    When they were perfectly sanded (about a months work) I undid the rod and split them:

    [IMG]http://development.crm-uk.com/images/speakers/splitinprimer.jpg[/IMG]

    Then I put based coat and clear coat while they were together again, then split them for colour sanding and machine polishing.

    [IMG]http://development.crm-uk.com/images/speakers/basses.jpg[/IMG]

    I used some 2mm foam sheet cut to match the profiles. Here you can see the rounded over joins as I’m building them upside down in the kitchen!

    [IMG]http://development.crm-uk.com/images/speakers/inprod.jpg[/IMG]

    Here’s the top after some colour sanding and machine polishing:
    [IMG]http://development.crm-uk.com/images/speakers/shinytop.jpg[/IMG]

    In situ side view
    [IMG]http://development.crm-uk.com/images/speakers/InSitusideview.jpg[/IMG]

    Both done:
    [IMG]http://development.crm-uk.com/images/speakers/InSitu.jpg[/IMG]

    I’ve started prototyping the centre speaker:
    [IMG]http://development.crm-uk.com/images/speakers/centreprototype.jpg[/IMG]

    They sound epic. I had to give them a nice new amp so a 400W/channel Lyngdorf 2-channel was purchased.

    They were built to be non-ported and tuned to about 45Hz but with some Dirac Live DSP, they’re able to drop to 32Hz

    Reply To: RE: My first DIY speaker project