Al Klappenberger Posted October 21, 2015 Share Posted October 21, 2015 (edited) A little transformer history: When my "Universal" was under development, I found I couldn't buy a Klipsch T2A transformer from the original source, Universal Transformer of Texas, because it was proprietary to Klipsch, so: I had Universal Transformer make a similar transformer that had an extra tap that was 15 dB attenuation and bifilar wound. At the same time I figured I would make it a bit larger. I really didn't need to. If I was doing it today, I wouldn't have. The T2 is quite large enough. It was designated the 3619. The tap marking pattern followed the T2A, 0 to 5. The extra tap could not be called 6 since that would imply it was near the top of the winding. It's near the bottom, so it became X. The extra tap allowed me to float the K55 between taps allowing intermediate attenuation settings. I let Universal Transformer to sell it to anybody. Later, Bob Crites had a transformer made with extra taps close to the top that would allow 1 dB steps. That was an improvement over the floating K55 scheme of the 3619. In keeping with the same tap numbering scheme, the new taps became X and Y, It didn't have the 15dB tap I called X on the 3619. As with the 3619, calling it tap 6 wouldn't make sense. This became the 3636. It is proprietary to Bob. Only he can buy it. Not long after, I realized that all the letters and numbers was confusing things, so I had Universal transformer add another tap to yield and 18 dB option and actually mark all of them in dB instead of cryptic numbers and letters. This became the 3619-ET that I use now. Only I can buy it. Dean decided that bigger is always better, so he had Universal Transformer simply make an even bigger transformer and keep the new tap marking scheme of the 3619-ET, Of course there's the wax dip. That procedure was replaced long ago by the sealant normally used by everybody else today. $10 per transformer is no big deal. Just pass it on to your customers. Clever! I might add that ALL of these transformers were actually designed by Mark Cooper of Universal Transformer. Al K. Edited October 21, 2015 by Al Klappenberger Link to comment Share on other sites More sharing options...
Al Klappenberger Posted October 21, 2015 Share Posted October 21, 2015 The responses shown in the plot are the K401 and PD5VH. I thought it looked like an old push-pin K55! Link to comment Share on other sites More sharing options...
Deang Posted October 22, 2015 Share Posted October 22, 2015 Mark Cooper's father is still living and they have all of the notes and diagrams. I was told PWK met with him and wanted wax potted units, since wax is thinner than water and only wax can completely permeate the windings. So you don't pass the cost of any of your parts on to your customers? Link to comment Share on other sites More sharing options...
John Warren Posted October 22, 2015 Author Share Posted October 22, 2015 (edited) I was able to "reverse engineer" your network schematic in less than a half hour. That statement, by itself, looks a little silly. Perhaps posting high resolution images of it on the web helped too(?) Anyone can look at the images you posted, draw out the components and follow the connecting wire. Perhaps anyone can but apparently no one cared to, but you of course.... With the exception of an unswamped autoformer, it's a pretty generic design. I never claimed it as being novel. The schematic was then sent to Al who used his software to compute probable component values. Seriously, you two geniuses had to work "together" to do this? If other forum members would like to see the probable component values, I can post it. No one cares For the three other forum members reading this thread. The plot below is the electrical response of a filter for a cone speaker. Load resistors are used and are non-inductive. A couple of variations are shown. The Group Delay of the electrical response is shown on the bottom. Group delay is a measure of phase distortion, units are seconds (ms). It's easy to determine with dedicated tools. Edited October 22, 2015 by John Warren Link to comment Share on other sites More sharing options...
Moderators Travis In Austin Posted October 22, 2015 Moderators Share Posted October 22, 2015 The emoticon should have been a (. Thanks Obama. Lee Is Al an engineer? Always wondered about that, given his company name is ALK Engineering? He stiil think Klipsch designs are "bad." Link to comment Share on other sites More sharing options...
John Warren Posted October 22, 2015 Author Share Posted October 22, 2015 (edited) The reason Al asked you to provide those electrical plots was, (a) to determine if you knew how to measure the parameters in question and, ( if you haven't done the measurements yet, what the heck are you doing in the crossover network business? what can you do other than do what the ALK expects of you? Edited October 22, 2015 by John Warren 1 Link to comment Share on other sites More sharing options...
rebuy Posted October 22, 2015 Share Posted October 22, 2015 I'm not saying the design of my crossover was "bad"--but the parts were pitiful--very low quality. Link to comment Share on other sites More sharing options...
Deang Posted October 22, 2015 Share Posted October 22, 2015 Yeah, but it doesn't matter, because they all sound the same. Stop it Doc, you're killing me. Link to comment Share on other sites More sharing options...
mikebse2a3 Posted October 22, 2015 Share Posted October 22, 2015 (edited) The reason Al asked you to provide those electrical plots was, (a) to determine if you knew how to measure the parameters in question and, ( if you haven't done the measurements yet, what the heck are you doing in the crossover network business? wtf can you do other than do what the ALK expects of you? Funny you guys keep throwing Grenades at John and he just keeps throwing your Grenades back to you... Might be time to "RETREAT" Edited October 22, 2015 by mikebse2a3 Link to comment Share on other sites More sharing options...
mikebse2a3 Posted October 22, 2015 Share Posted October 22, 2015 (edited) Mark Cooper's father is still living and they have all of the notes and diagrams. I was told PWK met with him and wanted wax potted units, since wax is thinner than water and only wax can completely permeate the windings. So you don't pass the cost of any of your parts on to your customers? Hang in there Dean.... I believe they are running out of ammunition.... Edit: Watch Out though if they start throwing crappy "Capacitors" at you.... Edited October 22, 2015 by mikebse2a3 Link to comment Share on other sites More sharing options...
Al Klappenberger Posted October 22, 2015 Share Posted October 22, 2015 what can you do other than do what the ALK expects of you? HUH?? Real filter desingers don't use "Bode plots". We use a "Smith chart". Acceptable impedance match must be inside the small dotted circle in the center. That represents 1.5:1 mismatch limit from the 6 Ohm standard forced on us by the K33 woofer impdeance. The plot is of your network. There's not much of it in there! Would you like to see mine? I would live to show it to you! BTW: The smith chart is used by microwave engineers becasue the outer circle represent 360 degrees down a transmission line. Any inner circle represents all the complex impedance possibilities that are a specific stading wave ratio or impedance mismatch. The usual impedance used at microwave is 50 or 75 Ohms. I have it set to 6 Ohms here. Al K. Link to comment Share on other sites More sharing options...
Al Klappenberger Posted October 22, 2015 Share Posted October 22, 2015 Shucks folks! I just couldn't wait for you to ask! Here's the Smith chart and response of my ES400 + ES5800 set for the Klipchorn. Do you see anything outside the 1.5:1 VSWR limit? Nope.. neither do I. Al K. Link to comment Share on other sites More sharing options...
John Warren Posted October 22, 2015 Author Share Posted October 22, 2015 (edited) BTW: The smith chart is used by microwave engineers becasue the outer circle represent 360 degrees down a transmission line. Any inner circle represents all the complex impedance possibilities that are a specific stading wave ratio or impedance mismatch. The usual impedance used at microwave is 50 or 75 Ohms. I have it set to 6 Ohms here. Al K. Thank you for clarifying (highlight mine). If I could see the benefits of impedance matching in the Bode plot, I'd be a believer, but... Edited October 22, 2015 by John Warren Link to comment Share on other sites More sharing options...
John Warren Posted October 22, 2015 Author Share Posted October 22, 2015 (edited) Shucks folks! I just couldn't wait for you to ask! No one cares. At this stage, If you feel a need for someone to listen to you can just send me PMs. Edited October 22, 2015 by John Warren Link to comment Share on other sites More sharing options...
spezjag Posted October 22, 2015 Share Posted October 22, 2015 I think that at this point, it is safe to say that there are fundamentally different philosophies being applied by the various cross-over network providers, both those represented in this thread, as well as others who have not yet weighed in. That's been the benefit of this thread - we can each see the arguments put forth by these vendors, and hopefully have received enough information for us the make our choices. We as consumers benefit from this, in that we now have numerous choices for our speakers. We can decide from whom we wish to buy from, and for what reasons (reasons that may or may not be entirely rationale - we're consumers, after all). Link to comment Share on other sites More sharing options...
Al Klappenberger Posted October 22, 2015 Share Posted October 22, 2015 John, You are actually quite correct. Microwave engineers do use the Smith chart rather then a Bode plot. Filter designers at any frequency actually use a measurement called "Return Loss". This represents the amount of energy bounced back to the source by an impedance mismatch. It relates directly to VSWR (Voltage Standing Waver Ratio) and mismatch error and combines both the resistive and reactive elements of a complex impedance in a single measurement. It is therefore actually displayed by network analysers and used by technicians to tune filters. The industry standard for most filters is 1.5:1 or 14 dB or more return loss. I adhere to this standard. At audio, the wavelength is so long that the Smith chard is not required. Around its outer circle would represent THOUSANDS of feet. Return loss however is still very convenient. The brown trace on the plots should be BELOW 14 dB. Here's a paste up of my ES400 + ES5800 set and your network. You shouldn't have to look very hard to see the same thing as shown on the Smith chart. The little circle in the middle of the Smith chart is the 14 dB return loss or 1.5:1 mismatch limit. I have added a 14 dB reference line to clarify the 14 dB return loss limit. One of these two networks is just a bit over the line! You are almost correct when you say nobody cares. Customers don't understand this stuff, but YOU SHOULD if you are going to try to design filters! Al K. Link to comment Share on other sites More sharing options...
Al Klappenberger Posted October 22, 2015 Share Posted October 22, 2015 (edited) Flatness 9 dB? Nope.. it's worse, it's more like 9.8 dB p-p including the crossover glitch. That's better than 13 dB with no network! I wonder what's happening below 1 KHz? Al K. Edited October 22, 2015 by Al Klappenberger Link to comment Share on other sites More sharing options...
Arkytype Posted October 22, 2015 Share Posted October 22, 2015 John, You wrote: "what can you do other than do what the ALK expects of you?" I guess someone at Klipsch removed the "double you tee eff" you started that mangled sentence with. While Al & I both suffer fools lightly, neither of us "expects" the other to do anything. Fortunately, we are of like minds on this thread's topic and as a result, our respective posts may overlap with similar sentiments. For those of you who don't know why John posted the two un-captioned Bode plots 10/21/15 @ 8:47, I'll tell you. The Bode plot on the right was a measurement by the late Richard C. Heyser, inventor of Time Delay Spectrometry or TDS. That Bode plot is part of the test report of a Klipschorn which appeared in the November, 1986 issue of Audio magazine. Guess John thinks that because Dick Heyser, PhD, presented his Bode plot, ol' John was in good company by posting his. The only thing you and the late Dick Heyser have in common is that you both have PhD degrees. The primary difference between you and Dick Heyser is that only one of you seems to be educated beyond his intelligence. Lee Link to comment Share on other sites More sharing options...
John Warren Posted October 22, 2015 Author Share Posted October 22, 2015 (edited) John, You wrote: "what can you do other than do what the ALK expects of you?" I guess someone at Klipsch removed the "double you tee eff" you started that mangled sentence with. While Al & I both suffer fools lightly, neither of us "expects" the other to do anything. Fortunately, we are of like minds on this thread's topic and as a result, our respective posts may overlap with similar sentiments. For those of you who don't know why John posted the two un-captioned Bode plots 10/21/15 @ 8:47, I'll tell you. The Bode plot on the right was a measurement by the late Richard C. Heyser, inventor of Time Delay Spectrometry or TDS. That Bode plot is part of the test report of a Klipschorn which appeared in the November, 1986 issue of Audio magazine. Guess John thinks that because Dick Heyser, PhD, presented his Bode plot, ol' John was in good company by posting his. The only thing you and the late Dick Heyser have in common is that you both have PhD degrees. The primary difference between you and Dick Heyser is that only one of you seems to be educated beyond his intelligence. Lee Actually, they happen to be complex impedance plots. Bode plots consist of 2 plots – both have logarithm of frequency on x-axis o y-axis magnitude of transfer function, H(s), in dB o y-axis phase angle ps: Heyser didn't earn a PhD either, U. Arizona BSEE '53, Cal Tech MSEE '54 . Edited October 22, 2015 by John Warren Link to comment Share on other sites More sharing options...
jimjimbo Posted October 22, 2015 Share Posted October 22, 2015 Well, I think that will about kill this thread.....it's been.....interesting..... Link to comment Share on other sites More sharing options...
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