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  • #16
    Originally posted by tomzarbo View Post

    That's a really cool looking speaker sir! Lots of performance packed in a smallish space. Those standoffs are sharp looking. I tried to cheap out making my own once, but those look really sharp.

    I bet a half-thickness of 'Ultra-Touch Denim insulation (2" split in half to 1" thick) placed in the mid chamber would do a lot to calm down internal reflections, that stuff has really good sound-absorbing properties in my observation.

    This looks like a high-end version of a 'desktop 3-way' but I really like the look of your other, Peerless desktop 3-way too.

    TomZ
    Thanks Tom! I'll give the Ultra-Touch Denim a shot, I think it's the same things as the "Eco-Core" that Meniscus carries, right?

    Yea, this would be considered the "high-end" version of the two. The driver cost on this one is twice the Peerless version, but it should excel in a few areas, or at least I hope it does. Still working on the Peerless version, it's almost time to decide on the veneer and cut the final cabinets. I liked your suggestion for the veneer on it, a burl sounds perfect.

    My "No-Name" CC Speaker
    Kerry's "Silverbacks"
    Ben's Synchaeta's for Mom
    The Archers
    Rick's "db" Desktop CBT Arrays
    The Gandalf's

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    • #17
      Very cool use of that woofer. I love a good boundary loaded design.

      Comment


      • #18
        Originally posted by Kevin K. View Post

        Thanks Tom! I'll give the Ultra-Touch Denim a shot, I think it's the same things as the "Eco-Core" that Meniscus carries, right?

        Yea, this would be considered the "high-end" version of the two. The driver cost on this one is twice the Peerless version, but it should excel in a few areas, or at least I hope it does. Still working on the Peerless version, it's almost time to decide on the veneer and cut the final cabinets. I liked your suggestion for the veneer on it, a burl sounds perfect.
        Yes, I looked and it looks to be exactly the same stuff. It's actually nice they sell it by the foot, that stuff is expensive!

        You like burl for that other speaker too? Hey, I had a good idea! It happens every once in awhile.

        Regarding changes from front- to down-firing, I didn't even check frequency response that I recall, just box tuning or Fs of the driver since it was a subwoofer. The other time I did that was with the Classic Tension Headaches with a down-firing port setup just like your woofer would be aiming towards a bottom base plate. Same deal there, just a bit lower tuning was all, but only by a few Hz.

        You take good pics. I used to but since I started using my phone they've gotten worse, not focused right. Gonna have to get my real camera out again!

        TomZ



        *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 *Cello's Speaker Project Page

        *Building the "Micro-B 2.1 Plate Amplifier -- Part 1 * Part 2 * Part 3 * Part 4 * * Part 5 'Review' * -- Assembly Instructions PDF

        Comment


        • #19
          OT... my wife orders big boxes of frozen bone broth from someplace. They come stuffed with soft touch denim insulation to keep the dry ice going for shipment.

          I've been hoarding it... the lady thinks I'm nuts

          Edit, on topic: Those look super cool Kevin. I love the sneaky 3 way and the use of those stand offs. I have a box of those in the basement too, just need something to use them on.
          Electronics engineer, woofer enthusiast, and musician.
          Wogg Music
          Published projects: PPA100 Bass Guitar Amp, ISO El-Cheapo Sub, Indy 8 2.1 powered sub, MicroSat, SuperNova Minimus

          Comment


          • Kevin K.
            Kevin K. commented
            Editing a comment
            Thank you Sir! Exactly, these will be sneaky. Looking forward to cranking the volume for someone that doesn't know about the woofers, should be fun to watch their facial reactions.

        • #20
          Not that you can change it now but I wondered if it would help to cut the PVC asymmetrically so one side is deeper than the other. It would change the angle internal to the mid so the reflections were not all focused back at the cone. Then damping down what is left.

          Not sure if that would help but it was on my mind laying in bed

          Comment


          • Kevin K.
            Kevin K. commented
            Editing a comment
            Thanks for sharing the idea Stephen. I'm thinking we'll be ok after lining the PVC with the Sonic Barrier, plus the added benefit of the Eco-Core. Am setting up as we speak to start taking measurements. Hoping to have a preliminary crossover by tomorrow evening. If I suspect something doesn't sound right after that, I'll start exploring options.

        • #21
          Originally posted by stephenmarklay View Post
          Not that you can change it now but I wondered if it would help to cut the PVC asymmetrically so one side is deeper than the other. It would change the angle internal to the mid so the reflections were not all focused back at the cone. Then damping down what is left.

          Not sure if that would help but it was on my mind laying in bed
          Yes- this would help immensely!
          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*

          Photobucket pages:
          http://photobucket.com/Wolf-Speakers_and_more

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

          Comment


          • #22
            Originally posted by Wolf View Post

            Yes- this would help immensely!
            Wolf
            Stephen's idea is the front runner for the midrange compartment change for now. Any of you ever use these? Thinking of bringing a pair in for a closer look.

            https://www.parts-express.com/eminen...sure--290-5506

            My "No-Name" CC Speaker
            Kerry's "Silverbacks"
            Ben's Synchaeta's for Mom
            The Archers
            Rick's "db" Desktop CBT Arrays
            The Gandalf's

            Comment


            • #23
              I haven't used one, and have not seen anyone use one, but these have not been for sale all that long.

              Later,
              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*

              Photobucket pages:
              http://photobucket.com/Wolf-Speakers_and_more

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

              Comment


              • #24
                Might have to use RTV for a gasket and a plug for the hole in back?

                Comment


                • Kevin K.
                  Kevin K. commented
                  Editing a comment
                  Yes Sir, thanks for the suggestion. Not sure if I'll be able to use them, but ordering a pair today. Listened to the speaker last night for the first time with a crossover, didn't hear anything alarming about how the mid sounded. Even so, I'll be making some kind of change to the shape of the chamber, there's room for improvement.

              • #25
                Preliminary crossover put together last night. Measurements taken at .5 meter, 1/24 smoothing, gated at 5ms. There will likely be some minor tweaks to the crossover to improve the horizontal off-axis performance, minor changes though. After the crossover was built, took some quick measurements to confirm and then went to work on the woofer's DSP. Nearfield measurement of the woofer after the low-shelf PEQ adjustment shows an F3 right around 40hz.

                Assessment of the midrange so far: Have recently been working on another 3-way that uses the paper cone Peerless SLS-85S25CP04-04 as the mid. The Ceramic driver sounds a little different too me, but not in a bad way. I'm thinking the difference I'm hearing is more related to driver quality and cone material than the possibility that the midrange chamber is effecting the sound. Can't say for certain due to my inexperience, because of this, I'll make some changes to the mid chamber in hopes of ruling that out.

                First impressions: This is going to be a fun little speaker!! Immediately after firing it up and throwing a little juice at it, my son came down from his upstairs room to see what was going on. He and I both were astonished at the output from this little guy. The mids and highs, IMO, are fantastic! The bass.....well, it's just ridiculous this much can come from something this small. Looking forward to sharing these with you guys at an upcoming event and getting your opinions.

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                Last edited by Kevin K.; 01-17-2020, 02:26 AM.
                My "No-Name" CC Speaker
                Kerry's "Silverbacks"
                Ben's Synchaeta's for Mom
                The Archers
                Rick's "db" Desktop CBT Arrays
                The Gandalf's

                Comment


                • #26
                  Very cool Kevin. I bet it will end up being a great speaker.

                  Comment


                  • #27
                    Can't argue with that, except your squiggly line doesn't have any squiggles to it!

                    If you managed to rouse Kole from the teen den upstairs, you must have been making some nice noises.

                    Just thinking about what you said about the ceramic mid sounding different than the peerless... it always amazes me how different my speakers sound from each other, though they all measure within a few dB of each other.

                    I just realized that you even did little recesses for the rubber 'anti-vibration' pads on the bottom where the bolts are. Nice touch.
                    TomZ
                    *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 *Cello's Speaker Project Page

                    *Building the "Micro-B 2.1 Plate Amplifier -- Part 1 * Part 2 * Part 3 * Part 4 * * Part 5 'Review' * -- Assembly Instructions PDF

                    Comment


                    • Kevin K.
                      Kevin K. commented
                      Editing a comment
                      Couldn't have said it better myself. If you can manage to get a teen to leave his den at his own will, you're on to something, lol. I think you're right, each speaker can have it's own signature sound based on many different variables, yet measure very close to each other. You know me, a detail freak, can't help myself. Thanks for noticing.

                  • #28
                    I agree with Tom, your squiggly meter might be broken since it wasn't really squigglying This is one of the most interesting projects I've seen in awhile. Looking forward to your progress.

                    Comment


                    • Kevin K.
                      Kevin K. commented
                      Editing a comment
                      You guys could be right, I might have a broken squiggly meter. Have tried this Omni-Mic on more than one computer to make sure the computer wasn't introducing anything into the measurements, it measured the same on both. Will see if I can borrow another mic from someone else long enough to confirm I'm getting good readings. Thanks for the kind words on the project, I'll keep you guys posted on the progress as it moves forward.
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