Announcement

Collapse
No announcement yet.

Philips 10100-8 10" woofer replacement in Transmission Line cabinets

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

  • #46
    Re: Philips 10100-8 10" woofer replacement in Transmission Line cabinets

    Amazed that no one was able to come up with a driver replacement for the Philips. Scan Speak had a 10" driver from their classic series that is now discontinued, I believe. I think Madisound only offers it in the version that is appropriate for a sealed cabinet. A version of the 25W/8565. The sealed version is -00 and I think the one that would be a good replacement for the Philips would be the -01. They sometimes show up on Ebay. As I recall, Martin became interested in transmission lines after being impressed with a Focal 10C01 in a 9' line. At that time, I'm guessing 25 years ago, Martin asked me if I thought that the wool stuffing in the line moved. I already had been experimenting with Sonotube and I could say without a doubt that I observed the wool moving at the end of a 6' tube with the driver mounted at the other end. Now, I have built transmission lines using both old and new math, and I prefer those with the longer lines. From my listening the shorter lines work fine producing low frequencies but they never seem to be as quiet. Several years ago I built a version of the 9' line with a Seas 8" aluminum driver. I didn't think it worked all that well and stored it in the basement, blamed the driver. Cleaning out my basement a few days ago I contemplated trashing the two rather large enclosures, but decided to give them a last listen. Initially, my observation was the same as before, but I found some organ music that was recently given to me and was amazed with the sound pressure produced by the lowest notes and rattling in my sound room. This is the quietest of the transmission lines that I have built by far. It's one thing for a transmission line design to go deep, another for it to be well behaved when there is nothing going on. I recently built a compound loaded sealed subwoofer and although it goes deep it is more busy compared to the transmission line. Setting all the math and wool stuffing aside, it should be intuitive why a longer line will work, provided that there is the right driver. Just sit in a quiet space, forget about the math and think about it. The Philips was one of those drivers. The Focal 10C01, although working well in a sealed cabinet, worked extremely well in a transmission line, not that hard to understand. Getting to the long fiber wool, it only works if it is properly prepared. The synthetics are impossible in a transmission line. I had been using Sonotube since it became first available. Fantastic material for a line. We had built 15 foot lines using the Philips drivers, fantastic. But, my favorite was two compound loaded drives loaded into the smallest reasonable tube with that tube loaded into a larger tube, so that he back wave exits just below the drivers. This is ultra quiet as the odd order harmonics, especially when playing vinyl are quieted. Overall, my experience is that the longer lines are easier to get right with the right drivers, and if you know how to prepare the wool, they are certainly quieter. You can play with the math all you want, I can do that. You're all entrenched in the security of certitudes, unable to offer your help to Mr. Keilau.

    Comment


    • #47
      Re: Philips 10100-8 10" woofer replacement in Transmission Line cabinets

      As a non-engineer, this has been a fun read!
      It seems Mr.bailey is now to TLs what Rube Golberg is to mouse traps.:D

      Comment


      • #48
        Re: Philips 10100-8 10" woofer replacement in Transmission Line cabinets

        Originally posted by biscuitbarrell View Post
        As a non-engineer, this has been a fun read!
        It seems Mr.bailey is now to TLs what Rube Golberg is to mouse traps.:D
        That's a bit harsh. Engineering, like all science, progresses with time. Many famous and unquestionably talented engineers and scientists had their share of erroneous beliefs and conclusions, it's just part of the process.

        Francis
        Francis

        Comment


        • #49
          Re: Philips 10100-8 10" woofer replacement in Transmission Line cabinets

          http://meniscusaudio.com/eclipse-w1038r-p-567.html

          Comment


          • #50
            Re: Philips 10100-8 10" woofer replacement in Transmission Line cabinets

            Like Face said, things have progressed a bit since the 60s. The fact that you're stuck there isn't our problem, it's yours.

            You insist that the wool is the magic and that the driver parameters don't factor in. Using your own logic, that means the woofer doesn't matter, not even a little.

            Now if you say that it does, and that somehow the Phillips woofer was an adequate substitute for the original KEF unit, what about them made them suitable for that particular line? Remember, we're talking about the range below 200Hz here, right in the region where TS parameters define the behavior of the cone, suspension, and motor assembly as a unit.

            It's not the wool that defines the behavior of the line. It's the wool's density and placement along the line that determine its effect on the line and how it affects the driver impedance and acoustic impedance that the driver sees.

            keilau, the fact of the matter is, you're wrong when you state that driver parameters don't matter, and deep down, you know it. Otherwise, you wouldn't be asking about a substitute woofer for the old Phillips. There's only one way to determine if a driver will match the Phillips performance in that line, and that's to know its Qts, Fs, and Vas. Those parameters will determine the low frequency behavior of the woofer in that line. Those parameters determine the low frequency performance of every woofer, regardless the enclosure. Those parameters work for sealed, open baffle, transmission line, passive radiator and bass reflex enclosures.

            What Bailey and Radford did can be modeled with Martin King's worksheets. The mathematical treatment Martin has applied to the system is repeatable, and verifiable, and has been proven over, and over, and over, and over, in the real world, with myriad woofers in a variety of lines.
            All the KEF (B139) drivers were not the same. They were made to spec. When we ordered the B139 there was another numerical designation. I believe they could be spec'd out to work in sealed or ported enclosures. As in the ScanSpeak 25W/8565-00 and-01. There's more to using wool than than placement or density. Because of the way that you're using it placement and density must be consistent. If you're using the wool in the "traditional" line preparation of the wool is specific. Using the wool as so many do using Martins worksheets will not work in the "traditional' line. It's in the literature, but I think most have missed or ignored it.

            Comment


            • #51
              Re: Philips 10100-8 10" woofer replacement in Transmission Line cabinets

              Thanks for posting this. I hope Mr. Keilau reads this. It's the help he was looking for.

              Comment


              • #52
                Re: Philips 10100-8 10" woofer replacement in Transmission Line cabinets

                Originally posted by fpitas View Post
                That's a bit harsh. Engineering, like all science, progresses with time. Many famous and unquestionably talented engineers and scientists had their share of erroneous beliefs and conclusions, it's just part of the process.

                Francis
                I read nothing harsh. Too many people seem to get pleasure from taking a bite of Mr. Bailey. Remember he helped get us started and we are only building on his ideas. If Bailey were in our time with the idea and with the resources we have available you would be talking about him differently. People have been harsh with their criticisms toward Mr. Bailey, but we owe him. I've taken his ideas and built on them with longer lines and they work perfectly, no humming, no bottoming out, etc... I've built transmission lines using the new math and they have been a disaster. A close friend built two 14' lines with 24" Hartleys and they are magnificent. Seems like too many people want to dismiss Mr. Bailey and make the transmission line exclusive to this era. There are a enough young people floating around that think Steve Jobs invented the computer.

                Comment


                • #53
                  Re: Philips 10100-8 10" woofer replacement in Transmission Line cabinets

                  Originally posted by biscuitbarrell View Post
                  As a non-engineer, this has been a fun read!
                  It seems Mr.bailey is now to TLs what Rube Golberg is to mouse traps.:D
                  Now, I think Mr. Bailey would appreciate your comment.

                  Comment


                  • #54
                    Re: Philips 10100-8 10" woofer replacement in Transmission Line cabinets

                    Originally posted by billfitzmaurice View Post
                    He's quoting pretty much verbatim from Bailey circa 1965. It's been proven time and time again to be simply wrong. The speed of sound in a fiber filled tube can be slowed, by a few percentage points, but that's all. He keeps referencing theory as it existed nearly fifty years ago. It's no more accurate than another prevailing theory of that era, that the smallest sub atomic particles were the electron, neutron and proton. Comparing Bailey's methods of speaker design to today's is about the same as comparing a cloud chamber to the Large Hadron Collider.
                    And 50 years from now someone will laugh at our transmission line theory. The broom is old and it still works.

                    Comment


                    • #55
                      Re: Philips 10100-8 10" woofer replacement in Transmission Line cabinets

                      Originally posted by martin View Post
                      I just looked back in my personal notes and found that I have been working on transmission lines for over 25 years. I have the articles you referenced and all the copies of Speakerbuilder. I analyzed many TL's using the methods in the referenced articles and compared the results against measured electrical impedance and SPL plots. The methods did not correlate, the calculated results based on these theories were wrong. I was not alone in this conclusion, check out the paper by Bullock and his experience with TL modeling.

                      So I designed and built a test TL and took many careful measurements, revisited all of my equations and fixed the mistakes resulting from following the articles you provided. The biggest mistake is the belief that the fibers move and slow the speed of sound. This was a fundamental error made by Bailey and Bradford in their AES articles.

                      At the same time I was formulating my models George Augspurger approached the problem with a different method of modeling and reached the same conclusions. Our two different calculation approaches produce the same answers for a given TL geometry. Both of us have produced excellent correlations between predictions and measured electrical impedance and SPL responses. Everything I have done is on my site for people to review and form an independent opinion. George Augspurger's work is presented in AES papers and in the Journal of the AES. Over the past 10 years many TL's have been designed by different users of my MathCad worksheets and after building them the measured results matched the predictions. Sounds pretty well wrapped up to me.

                      Don't like or believe in the newer more modern TL design theory and want to stick with the work from the late 60's and early 70's is fine by me. Can you show calculated results with enough detail that they can be checked and then produce a build with measurements that correlate against the predictions? I can. Since I have not seen any real work from you in my opinion your posts do not carry a lot of weight. Bring something to the table for people to chew on, more then just words telling others with years of successful experiences that they are wrong. Not much point in continuing a one sided conversation. Your move.
                      The fibers may not slow the speed of sound, but they do move.

                      Comment


                      • #56
                        Re: Philips 10100-8 10" woofer replacement in Transmission Line cabinets

                        But the theory of the past was proven incorrect. Nothing against Bailey or any of the audio pioneers. We are thankful for their ideas and spirit. But just as in other areas we have advanced. Martin and others have developed the models that with accurate input have time and again to be correct. Why is this so hard to understand? The old is better because?????
                        https://www.facebook.com/Mosaic-Audi...7373763888294/

                        Comment


                        • #57
                          Re: Philips 10100-8 10" woofer replacement in Transmission Line cabinets

                          New troll is more polite than the original troll.

                          Comment


                          • #58
                            Re: Philips 10100-8 10" woofer replacement in Transmission Line cabinets

                            Originally posted by djg View Post
                            New troll is more polite than the original troll.
                            +1
                            Francis

                            Comment


                            • #59
                              Re: Philips 10100-8 10" woofer replacement in Transmission Line cabinets

                              I don't believe it's fair to call him a troll. He has said nothing but his own opinion. Let the discussion continue.
                              https://www.facebook.com/Mosaic-Audi...7373763888294/

                              Comment


                              • #60
                                Re: Philips 10100-8 10" woofer replacement in Transmission Line cabinets

                                Originally posted by isaeagle4031 View Post
                                I don't believe it's fair to call him a troll. He has said nothing but his own opinion. Let the discussion continue.
                                Agree,and this has been a very informative discussion for me as well as entertaining
                                I Started Out with Nothing and I Still Got Most of It Left ...

                                Comment

                                Working...
                                X