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Credit due, better late than never!

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  • Credit due, better late than never!

    Approximately ten years ago, I built a pair of RJB Audio, (Roman Bednarek), "Alpheus MkII" speakers. Thought it was about time to give Roman a bit of praise and thanks.

    You can find his write up and build here.

    In my build, the cabinets have a gradual curve to the back. The baffles are 1 1/2 inch thick, as are also the top and bottom. I used two layers of flexi-ply to achieve 3/4 inch thick curved sides.

    The cabinet is braced with a shelf brace between the upper and lower cabinet spaces, a window brace between the tweeter and mid-woofer, a window brace directly behind the woofer and a window brace above and below the woofer, asymmetrically spaced. The crossover was out-boarded for convenience sake as they are quite large.

    The veneer is cabinet grade walnut, finished with medium walnut Danish oil and tung oil, hand rubbed.The baffles are covered with "Marshall" style vinyl cabinet covering. The speaker grill covers are held in place with neodymium magnets, counter sunk into baffle and speaker grill frames.

    Much of the misc parts were sourced from PartsExpress: XT19 tweeter, caps, inductors, resistors, sonic barrier, neodymium magnet disks, grill cloth, vinyl cabinet covering, polyfill, port.

    These speakers are solid performers, tight and extended base, mid-range is smooth, natural, etch free, voices and any string instrument are spot on and luscious. The ring tweeters just do their thing, light, airy with right amount of sparkle. .Good imaging and sound stage with lead singers stepping out and front n center.


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  • #2
    Very nice. I have made RJBs Microbes and Cerberus sub 2.1 in the past. I have enjoyed his designs.
    Well executed.


    • #3
      Thanks Andy!

      It was a fun but challenging build. Only real issue was the baffle vinyl covering pulling away from the driver counter sink.
      RJB has some nice designs, although my build is a NLA with regards to the Peerless Exclusive HDS Mid-range driver.
      Have really enjoyed these speakers!!



      • #4
        The relief detail at top and bottom is a nice addition. It adds definition. Great overall presentation! It seems like that Seas woofer is a good value.


        • #5
          These are stunning! Love the chamfers.
          Break in period = The time it takes for the new speakers to break in. And the time it takes for you ears to get adjusted to the new speakers.


          • #6
            Classically good looking cabinets, really beautiful. Great grills as well.
            The rear easily accessible crossover compartment is really a great idea too.

            Good work Sir!

            Zarbo Audio Projects Youtube Channel: * 320-641 Amp Review Youtube: *Veneering curves, seams, using heat-lock iron on method *Trimming veneer & tips *Curved Sides glue-up video
            *Part 2 *Gluing multiple curved laminations of HDF