Announcement

Collapse
No announcement yet.

My MWAF entry... the Summer Winds: Good Grief... How could I be so Stupid???

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • My MWAF entry... the Summer Winds: Good Grief... How could I be so Stupid???

    Click image for larger version

Name:	SW.jpg
Views:	1
Size:	162.4 KB
ID:	1382329

    Boy, am I ever upset with myself.
    As soon as the judges heard the pink noise, they knew something was off. Yeah, me... I was off. :(

    Somehow in my haste to finish these, I managed to wire one of the tiny midwoofers on one of the speakers in reverse phase. The two drivers on that side were effectively cancelling each other out.

    Funny thing is, it wasn't very noticeable with music for some reason. I listened to them for about an hour at home to let the drivers break in a bit before packing them in the car Thursday evening... and I didn't hear anything amiss; though I probably wasn't thinking clearly exactly. My wife only heard the issue this morning at low volume... she's got better ears than me! She IS a lot closer to them than me, though.

    I knew these things had very little chance of actually being competitive, but still I always want to bring my best work and effort, and I really messed up this time. I just wonder how I missed that obvious mistake.

    This is how I found the problem: I hooked up Omnimic and did the short sweep while holding the mic close to each cone. The impulse response graph (the lower one) starts either going up, or down based on the polarity of the driver. Well, all of the front drivers displayed the waveform moving downward initially, except for the upper midwoofer on one speaker. NUTS!!!!! I don't know how I missed that or didn't think to double check this, but I did. Boy do I ever regret missing that. I tried the easy battery test, but the midwoofers didn't move enough with a 1.5 volt cell for me to tell. Of course, once I got the drivers out, I saw that the red wire was hooked to the negative on the upper midwoofer on one speaker... what a sinking feeling.

    After the judges hear something that messed up phase-wise on the pink noise, how could they even take it seriously after that? Nope, I did it to myself this time. Well, that won't happen again!

    Just wanted you guys to know what the issue was and that it wasn't the equipment there, just the equipment in my brain.

    Well like I said, i doubt they would have been competitive given the competition... man, did most of those speakers sound really swell this year.... but I'm sure you guys can understand... you want to do your best and bring your best effort... and I screwed up this time. I'm just shaking my head at this point. Well, at least my niece, Summer will get the 'new and improved' version when I deliver them in a few weeks.

    On a side note, I REALLY enjoyed talking with everyone this year. I hope you guys know that I really appreciate you all and what you add to the whole community. I had a lot of fun and don't regret the outing, even though I borked my entry up royally. My back was killing me by the end and we scooted out quickly after the winners were announced so I didn't get to say goodbye to everyone officially, but I just wanted everyone that I spoke with to know that I enjoyed the discussions. It's nice to hang with fellow speaker-crazies.

    Thanks to PE and the really nice friends/folks who are employed by them for being so kind to us and treating us like kings/queens. Everyone there is really nice all the time. It was another really great MWAF and I'm already looking forward to next year.

    And I wonder.... how is Meredith going to top this year's massive horn-loaded subwoofer project next year?????

    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

  • #2
    Ouch!!!! You spend all that time building and then --- one small, little connection mistake. Wow. I felt kind of bad for you when this happened.

    When I was building the Totally Flat speakers I could not get the final system Z curves to match. Tracked it down to a partially shorted out 2.5mH inductor, of all things!!! So I unwound the inductor and rewound it backwards. It was no longer shorting, but on the re-wind it only measured 2.1mH. So I had to add a small length of 18ga magnet wire to bring it back up to 2.5mH. I was paranoid, so I re-checked the Z curve before loading them into the car. They seemed to work just fine at the show.
    Plumber's Delight: http://techtalk.parts-express.com/fo...notech-winners
    Linehopper: http://techtalk.parts-express.com/sh...Esoteric-build
    Plan-Tanic: http://techtalk.parts-express.com/sh...ght=Plan-Tanic

    Comment


    • #3
      Originally posted by tomzarbo View Post
      Click image for larger version

Name:	SW.jpg
Views:	1
Size:	162.4 KB
ID:	1382329

      Boy, am I ever upset with myself.
      As soon as the judges heard the pink noise, they knew something was off. Yeah, me... I was off. :(

      Somehow in my haste to finish these, I managed to wire one of the tiny midwoofers on one of the speakers in reverse phase. The two drivers on that side were effectively cancelling each other out.

      Funny thing is, it wasn't very noticeable with music for some reason. I listened to them for about an hour at home to let the drivers break in a bit before packing them in the car Thursday evening... and I didn't hear anything amiss; though I probably wasn't thinking clearly exactly. My wife only heard the issue this morning at low volume... she's got better ears than me! She IS a lot closer to them than me, though.

      I knew these things had very little chance of actually being competitive, but still I always want to bring my best work and effort, and I really messed up this time. I just wonder how I missed that obvious mistake.

      This is how I found the problem: I hooked up Omnimic and did the short sweep while holding the mic close to each cone. The impulse response graph (the lower one) starts either going up, or down based on the polarity of the driver. Well, all of the front drivers displayed the waveform moving downward initially, except for the upper midwoofer on one speaker. NUTS!!!!! I don't know how I missed that or didn't think to double check this, but I did. Boy do I ever regret missing that. I tried the easy battery test, but the midwoofers didn't move enough with a 1.5 volt cell for me to tell. Of course, once I got the drivers out, I saw that the red wire was hooked to the negative on the upper midwoofer on one speaker... what a sinking feeling.

      After the judges hear something that messed up phase-wise on the pink noise, how could they even take it seriously after that? Nope, I did it to myself this time. Well, that won't happen again!

      Just wanted you guys to know what the issue was and that it wasn't the equipment there, just the equipment in my brain.

      Well like I said, i doubt they would have been competitive given the competition... man, did most of those speakers sound really swell this year.... but I'm sure you guys can understand... you want to do your best and bring your best effort... and I screwed up this time. I'm just shaking my head at this point. Well, at least my niece, Summer will get the 'new and improved' version when I deliver them in a few weeks.

      On a side note, I REALLY enjoyed talking with everyone this year. I hope you guys know that I really appreciate you all and what you add to the whole community. I had a lot of fun and don't regret the outing, even though I borked my entry up royally. My back was killing me by the end and we scooted out quickly after the winners were announced so I didn't get to say goodbye to everyone officially, but I just wanted everyone that I spoke with to know that I enjoyed the discussions. It's nice to hang with fellow speaker-crazies.

      Thanks to PE and the really nice friends/folks who are employed by them for being so kind to us and treating us like kings/queens. Everyone there is really nice all the time. It was another really great MWAF and I'm already looking forward to next year.

      And I wonder.... how is Meredith going to top this year's massive horn-loaded subwoofer project next year?????

      TomZ
      Well that sucks! At least you found the issue.
      -Kerry

      www.pursuitofperfectsound.com

      Comment


      • #4
        Thanks for sharing. Live and learn. Beautiful speakers, though. You are approaching a master's degree in woodworking.

        I think I hear a difference - wow, it's amazing!" Ethan Winer: audio myths
        "As God is my witness I'll never be without a good pair of speakers!" Scarlett O'Hara

        High value, high quality RS150/TB28-537SH bookshelf - TARGAS NLA!
        SB13/Vifa BC25SC06 MTM DCR Galeons-SB13-MTM
        My Voxel min sub Yet-another-Voxel-build

        Tangband W6-sub

        Comment


        • #5
          ...and we also can't say they were ugly!
          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


          • #6
            Oh that sucks, I can empathize because I’d likely make the same mistake!

            Comment


            • #7
              I use a app called "Speaker Pop" on iPhone to double check polarity on everything.
              Even when you are very sure everything is right, it's a great why to double check
              and rest assured.
              Guess xmax's age.

              My guess: 15. His grammar is passable. His trolling is good.

              Comment


              • #8
                Thomas, are all those speakers in the picture your doing? Really nice work!
                http://techtalk.parts-express.com/fo...khanspires-but
                http://techtalk.parts-express.com/fo...pico-neo-build
                http://techtalk.parts-express.com/fo...ensation-build

                Comment


                • #9
                  Wow Tom, that really stinks. Sorry the judges didn't get to hear your work the way it was meant to be. They look great though.
                  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


                  • #10
                    Tom, don't beat yourself up, and give yourself more credit. I'm sure they sound great. Glad you had fun.

                    Comment


                    • #11
                      One time during my crossover tweaking for the Cabalettas, after making some changes I played some more music and what I had been chasing seemed to be much improved; however, a short time later I realized something sounded odd. It turned out I hadn't solidly reconnected one lead from the woofer to its terminal post on the crossover assembly, so only one woofer was playing. Sure glad it happened then and not right before going to MWAF.
                      Paul

                      Comment


                      • #12
                        Thanks guys for not beating me up more than I've already done to myself. I still feel the need to don the 'dunce' cap for a little longer, though.
                        Kevin, it's so strange, but they sounded good with a nice soundstage even with one of the mids reversed somehow. Better now, but still, It's amazing that they didn't sound awful the way they were.

                        Thanks Kornbread, yup, those are some of the speakers I've built from the past few years. All of the curvy ones I still own are there in that room.

                        Xmax, how does that app work? Does it generate a tone, then use the mic to 'hear' if the driver is moving in or out? They didn't move enough for me to be sure of polarity with a 1.5v AA battery.

                        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


                        • #13
                          Originally posted by tomzarbo View Post
                          Click image for larger version

Name:	SW.jpg
Views:	1
Size:	162.4 KB
ID:	1382329

                          Boy, am I ever upset with myself.
                          As soon as the judges heard the pink noise, they knew something was off. Yeah, me... I was off. :(

                          Somehow in my haste to finish these, I managed to wire one of the tiny midwoofers on one of the speakers in reverse phase. The two drivers on that side were effectively cancelling each other out.

                          Funny thing is, it wasn't very noticeable with music for some reason. I listened to them for about an hour at home to let the drivers break in a bit before packing them in the car Thursday evening... and I didn't hear anything amiss; though I probably wasn't thinking clearly exactly. My wife only heard the issue this morning at low volume... she's got better ears than me! She IS a lot closer to them than me, though.

                          I knew these things had very little chance of actually being competitive, but still I always want to bring my best work and effort, and I really messed up this time. I just wonder how I missed that obvious mistake.

                          This is how I found the problem: I hooked up Omnimic and did the short sweep while holding the mic close to each cone. The impulse response graph (the lower one) starts either going up, or down based on the polarity of the driver. Well, all of the front drivers displayed the waveform moving downward initially, except for the upper midwoofer on one speaker. NUTS!!!!! I don't know how I missed that or didn't think to double check this, but I did. Boy do I ever regret missing that. I tried the easy battery test, but the midwoofers didn't move enough with a 1.5 volt cell for me to tell. Of course, once I got the drivers out, I saw that the red wire was hooked to the negative on the upper midwoofer on one speaker... what a sinking feeling.

                          After the judges hear something that messed up phase-wise on the pink noise, how could they even take it seriously after that? Nope, I did it to myself this time. Well, that won't happen again!

                          Just wanted you guys to know what the issue was and that it wasn't the equipment there, just the equipment in my brain.

                          Well like I said, i doubt they would have been competitive given the competition... man, did most of those speakers sound really swell this year.... but I'm sure you guys can understand... you want to do your best and bring your best effort... and I screwed up this time. I'm just shaking my head at this point. Well, at least my niece, Summer will get the 'new and improved' version when I deliver them in a few weeks.

                          On a side note, I REALLY enjoyed talking with everyone this year. I hope you guys know that I really appreciate you all and what you add to the whole community. I had a lot of fun and don't regret the outing, even though I borked my entry up royally. My back was killing me by the end and we scooted out quickly after the winners were announced so I didn't get to say goodbye to everyone officially, but I just wanted everyone that I spoke with to know that I enjoyed the discussions. It's nice to hang with fellow speaker-crazies.

                          Thanks to PE and the really nice friends/folks who are employed by them for being so kind to us and treating us like kings/queens. Everyone there is really nice all the time. It was another really great MWAF and I'm already looking forward to next year.

                          And I wonder.... how is Meredith going to top this year's massive horn-loaded subwoofer project next year?????

                          TomZ
                          I.had the same problem at the Meniscus event earlier this year.
                          craigk

                          " Voicing is often the term used for band aids to cover for initial design/planning errors " - Pallas

                          Comment


                          • #14
                            Originally posted by tomzarbo View Post
                            Thanks guys for not beating me up more than I've already done to myself. I still feel the need to don the 'dunce' cap for a little longer, though.
                            Kevin, it's so strange, but they sounded good with a nice soundstage even with one of the mids reversed somehow. Better now, but still, It's amazing that they didn't sound awful the way they were.

                            Thanks Kornbread, yup, those are some of the speakers I've built from the past few years. All of the curvy ones I still own are there in that room.

                            Xmax, how does that app work? Does it generate a tone, then use the mic to 'hear' if the driver is moving in or out? They didn't move enough for me to be sure of polarity with a 1.5v AA battery.

                            TomZ
                            You just hold your phone mic (connected to system through the headphone jack) close to the driver and it sends out a "tick" sound, the great thing about the app;
                            It works with tweeters and mids or anythiung else with a hi-pass/band-pass filter or dsp (unlike the battery trick). It's very nice and like 5 bucks.
                            Last edited by xmax; 07-17-2018, 08:47 PM.
                            Guess xmax's age.

                            My guess: 15. His grammar is passable. His trolling is good.

                            Comment


                            • #15
                              We've all had issues at one time or another...
                              I recall Dayton DIY 2004 where I lost a spring for a spring terminal, and a couple attendees and I searched for it while 2 other sets played. After that- no more spring clips for me.
                              At InDIYana 2008, I apparently blew a midrange or it developed a rub in my Icthus towers. I chalked it up to questionable surplus capacitors, and swapped both them and the ill midrange and all was well post-event. The problem I felt was initiated by a test-tone centered around the xover point on the midrange, and maybe both the cap and the mid got more than I bargained for.
                              Fenghuang at MWAF overexcursed with Lorde's Royals, when they really shouldn't play that low anyway. I gave those to Jerry's boy Simon that following November, and they both love that design. It just isn't good for bass.
                              In my Cecropia project with the first woofer CAW634 also had issues with excursion at InDIYana playing that torturing test track from Patricia Barber. The Supreme version was able to handle it.

                              I recall Kevin Kendrick had a wiring snafu on his Gandalfs last year at MWAF.

                              My buddy Steve had a level imbalance in the Unlimited category this year.

                              Javad had disconnected woofers on one channel of the Ceramicos this time. Apparently a coil broke loose internally and severed the connection.

                              Sometimes, it just happens, and with these Drag Races they are usually sending these contestants with issues to rebuild their engines.

                              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

                              Working...
                              X