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Finishing a Recession Buster Reference kit.... 11 years later!

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  • Finishing a Recession Buster Reference kit.... 11 years later!

    man, time flies. In September of 2009, Madisound offered a "Recession Buster Reference" speaker kit that used Revelator 5.5" woofers and SB Acoustics SB29 tweeters. When I bought this kit, my son was 3 months old. That fall, I got the cabinets built, stained, and clearcoated. For some inexplicable reason, I decided to use brush-on Poly instead of spraying it with automotive clear like I should have done. I sanded, and sanded, and sanded, then went through, re-brushed, sanded, sanded, etc. Eventually I got preoccupied with other things, and next thing I know, it's been 11 years. I finally decided that enough was enough, and I got back to work on them. I sanded, and sanded, and sanded, then re-cleared with spray-on poly. Once that fully cured, I sanded, and sanded, and sanded...



    I started at 1k, then 1500, 2000, then 2500. I think this pic was while I was still at 1000 grit:


    Once I made it through all the grits, that mind-numbing boredom paid off. It only took me about 20 minutes per speaker to buff them with rubbing compound:


    After the rubbing compound, I did it again with swirl remover, which really added a lot of depth:


    I had to paint the front baffles, and I wanted a matte gray. What I went with was actually a "cast iron" paint from Napa, but despite the odd purpose, it gave exactly the color that I was after:


    One hurdle that I'd never considered was fitting the crossover into the enclosure. The enclosure was built to the original design specifications, but I also added bracing between the stiffening baffles that prevented me from being able to stand up the crossovers along the back wall of the enclosures. Oops.

    Before:


    After an encounter with my chop saw:


    After I installed them into the enclosure with large amounts of hot glue, I realized that I never soldered the driver wires to the crossovers, and I also soldered the input to the woofer filter to the wrong terminal. Doing the solder work with these installed was NOT easy.


    Finally I was able to install the drivers (temporarily) to do a function check! After all of this effort, the woofers are all cut up and both tweeters are pushed in!



    Everything checked out, and I spent just a couple minutes listening to them. Initial impressions are very positive, though there were a couple things that I keyed in on... somewhat diffused imaging, and an apparent lack of bass, perhaps from a crossover that doesn't employ a full 6dB of baffle step. It was just a real quick listen, and at this point I didn't have any of the stuffing materials in the cabinets yet, so hopefully once I really get these finished, some of those concerns won't be an issue any longer.

    I'm getting very close to finishing these, and I'm getting very anxious. Hopefully this week I'll get them put back together for good. I still need to finish the grills, but at least I can be using them while I do that.

    It feels really good to be so close to completion after starting these things 11 years ago.

  • #2
    A blast from the past. Here's mine, since sold. As far as bass, I found mine had loads, no sub needed. 80 watt HK receiver. Yours look very nice.

    Click image for larger version  Name:	rrb2.jpg Views:	0 Size:	45.6 KB ID:	1467412

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    • #3
      Give it some time to loosen up. The revelator has about the best bass you can find in a 5" woofer.

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      • #4
        I'm sure they'll dig deep and provide great bass once they loosen up. I quickly set them up in place of a set of Mission 707 8" 2-way speakers and I didn't reconfigure the sub, so the "bass shy" sound may just have been because the speaker levels weren't well matched. Once I get them done I need to do some proper listening without the sub.

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        • #5
          Tonight I added damping material to the enclosure. It's 1/2" acoustic tile (doubled up on the top and bottom panels) and egg crate foam.

          Just the wool:


          foam top and bottom and behind the midbass and tweeter. No foam behind the port.


          another layer of wool behind the mid.

          Two more layers of foam behind the mid and one more behind the tweeter.

          Comment


          • djg
            djg commented
            Editing a comment
            IIRC, the only recommended and supplied treatment in the kit was Acousta stuf. That's all I used. If that "acoustic tile" material is like thick felt, it will reduce the volume of your enclosure.

        • #6
          Originally posted by jim85iroc View Post
          ...started at 1k, then 1500, 2000, then 2500...
          ...made it through all the grits ... 20 minutes per speaker to buff them with rubbing compound...
          ...did it again with swirl remover...
          Beautiful finish on those.



          "Our Nation’s interests are best served by fostering a peaceful global system comprised
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          A Cooperative Strategy for 21st Century Seapower
          (a lofty notion since removed in the March 2015 revision)

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          • jim85iroc
            jim85iroc commented
            Editing a comment
            Thanks. It's not perfect, but overall I'm quite happy with it.

        • #7
          Beautiful, nice treatment of the darker edges. They came out really nice, baffle too!

          TomZ
          Zarbo Audio Projects Youtube Channel: https://www.youtube.com/channel/UCEZ...aFQSTl6NdOwgxQ * 320-641 Amp Review Youtube: https://youtu.be/ugjfcI5p6m0 *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

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          • #8
            Diffuse image? Short bass? Sounds like a woofer/tweeter could be flipped. Flip cab polarity and see if bass comes in and image is still odd.
            Wolf
            "Wolf, you shall now be known as "King of the Zip ties." -Pete00t
            "Wolf and speakers equivalent to Picasso and 'Blue'" -dantheman
            "He is a true ambassador for this forum and speaker DIY in general." -Ed Froste
            "We're all in this together, so keep your stick on the ice!" - Red Green aka Steve Smith

            *InDIYana event website*

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            My blog/writeups/thoughts here at PE:
            http://techtalk.parts-express.com/blog.php?u=4102

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            • jim85iroc
              jim85iroc commented
              Editing a comment
              That's possible, but I don't think it was the case. I listened briefly to 1 speaker and it was pretty much the same. I think the bass was mostly because the subwoofer is matched to the speakers that are usually in that system, which are much more efficient, so when I swapped these in, the upper bass sounded weak because the sub was overpowering. Once I get them back together I'll listen without the sub. The diffused image could be as simple as not having them positioned properly on the stands, or could be because I had absolutely no damping in the enclosures. I'm not putting much faith in what I initially heard because they were literally just set on the stands, plugged in and listened to for 5 minutes.

              I should be able to get them back together tonight, and as I put them together I'll ring out the wiring to confirm correct polarity. Hopefully tomorrow I'll get a little bit of quality time with them after setting them up properly.

          • #9
            The speakers are finished. I still need to finish the grills, and make new stands. I have stands that I built for them, but I don't like them, plus now one of them will be sitting on top of a subwoofer, so I will need different ones anyway.

            I'm very happy with the damping. Talking into a damped cabinet then an undamped cabinet was like turning the reverb off my guitar amp.

            When I hooked them up, I took care to position them properly, and I shut off the subwoofer so that I was listening to just these. I've only listened to a few songs so far, but the vocals are solidly anchored in the middle, the bass is deep and accurate. I need to spin more tunes before I make any final judgement, but I doubt that I'll be disappointed.







            ​​​


            ​​​​​​

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            • djg
              djg commented
              Editing a comment
              Lovely, should have kept mine.

          • #10
            so, I've had a few days to listen to these, and I've made some observations. The lack of baffle step that I made mention to in my initial listening impression was primarily because I felt that male vocals sounded a bit thin. That remains. I went back and looked at the published frequency response graph for this design and there's a bit of a lower output region between 300hz to about 700hz, followed by a bit of a bump in output at 800hz. I think this is what I'm hearing. I'm getting used to it, but I definitely don't feel that this trait is ideal. Aside from this, I'm very impressed with how these sound. The bass is fantastic, and everything is very clean & detailed. Center imaging is fantastic, and the overall soundstage is too. Damping the speakers seemed to really improve the overall sound and tightened up the midrange a bunch. Now that I've been listening to these for a few days, I want to swap back to some of my other speakers and see how those sound now.

            Oh, and I also made some grills that I hate the appearance of. I need to revisit my grill idea, maybe with a partial roundover to help tie it into the baffle better.


            Comment


            • #11
              Jim, can I ask how you did the dark edges on the cabinet? Rattle can and careful spray angles?

              And could you apply a round over painted black to the grill to spruce it up a bit? I have trouble with grills too, So I really just don't usually do them. Maybe you can save them that way.

              TomZ
              Zarbo Audio Projects Youtube Channel: https://www.youtube.com/channel/UCEZ...aFQSTl6NdOwgxQ * 320-641 Amp Review Youtube: https://youtu.be/ugjfcI5p6m0 *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

              Comment


              • djg
                djg commented
                Editing a comment
                Yes, duplicate the mitered quarter round profile of the baffle.

              • jim85iroc
                jim85iroc commented
                Editing a comment
                Tom, all of the coloring was done with dyes. I did the brown first, then spotted in some yellows and reds which really aren't even visible, then I rubbed the black dye in around the edges. This is a pretty common finishing technique for electric guitars.

                And yeah, I'm going to put a partial roundover on the grills and see how that looks.

                Djg, I don't want that much roundover on the grills because there's not enough material to do that. They're pretty narrow near the woofers. I think I want to try a 3/4" roundover on the 1/2" material.

            • #12
              Thanks Jim. I'm guessing you used the dye before any type of finish, on bare veneer in other words.
              I think I saw a video of a TT member who used rattle cans, and I can't remember if that was pre- or post-finish.

              TomZ
              Zarbo Audio Projects Youtube Channel: https://www.youtube.com/channel/UCEZ...aFQSTl6NdOwgxQ * 320-641 Amp Review Youtube: https://youtu.be/ugjfcI5p6m0 *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

              Comment


              • jim85iroc
                jim85iroc commented
                Editing a comment
                Yeah, dye on bare wood, then clear. If you spray the burst, typically you'd do that after some sanding sealer or after a couple coats of clear.

            • #13
              I was quite tempted to buy the kit for these way back when, definitely the most affordable way to aquire a revelator driver in a design. Thanks for the great pictures, you did a great job all around!

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