John Warren Posted October 9, 2015 Author Share Posted October 9, 2015 (edited) <SNIP> Edited October 14, 2015 by John Warren Link to comment Share on other sites More sharing options...
John Warren Posted October 9, 2015 Author Share Posted October 9, 2015 I won't start by criticizing your numerous grammar or spelling errors in your forum post and web site; instead let's start with how your "top-section baffle insert" is going to sound based upon your published data. But you just did. Need to keep an eye on you. Link to comment Share on other sites More sharing options...
Wolfbane Posted October 9, 2015 Share Posted October 9, 2015 We now have three different ways of upgrading the top section of a Heritage Loudspeaker. I understand that John's is specific to the Klipschorn, but still ... If I were a complete novice, it would be difficult for me to examine these various solutions and make an informed choice, since the vendors haven't done anything to help me understand what the differences are, why they matter, and why one should be chosen over another. Just an observation. I see your point Dean. However, it is very difficult to point out differences, deficiencies, or points of interest, without attacking each others products. Dave I depend on my ears to tell me what I like better. Works for me. Link to comment Share on other sites More sharing options...
Wolfbane Posted October 9, 2015 Share Posted October 9, 2015 Good for killing mechanical vibration. Another one of those things -- are film and foils microphonic? That's why I use oil filled caps, I don't have to worry about it, and no poo! Why not just use thick 2 sided tape between things? The good stuff comes in white, doesn't get brittle for decades and is easily removed with some bare wire if used Luca Brasi style. 1 Link to comment Share on other sites More sharing options...
John Warren Posted October 9, 2015 Author Share Posted October 9, 2015 (edited) So, either the Selenium horn or your network is causing an unacceptable dulling of vocals where our hearing is most sensitive. Lee But is sounds pretty damn good and no dulling as you're inferring. Edited October 14, 2015 by John Warren Link to comment Share on other sites More sharing options...
John Warren Posted October 9, 2015 Author Share Posted October 9, 2015 (edited) Good for killing mechanical vibration. Another one of those things -- are film and foils microphonic? That's why I use oil filled caps, I don't have to worry about it, and no poo! Why not just use thick 2 sided tape between things? The good stuff comes in white, doesn't get brittle for decades and is easily removed with some bare wire if used Luca Brasi style. One could use double sticky but tape gets messy with dust, cat hair and other things floating around the room. Keep the ideas coming however. Edited October 9, 2015 by John Warren Link to comment Share on other sites More sharing options...
John Warren Posted October 9, 2015 Author Share Posted October 9, 2015 """I don't like parts rubbing into each other when handled""" I thought we were talking about crossovers? That didn't even cross my mind. Am I that far gone? Link to comment Share on other sites More sharing options...
jimjimbo Posted October 9, 2015 Share Posted October 9, 2015 Good for killing mechanical vibration. Another one of those things -- are film and foils microphonic? That's why I use oil filled caps, I don't have to worry about it, and no poo! Why not just use thick 2 sided tape between things? The good stuff comes in white, doesn't get brittle for decades and is easily removed with some bare wire if used Luca Brasi style. You could also use a knife, Sollozzo style..... Link to comment Share on other sites More sharing options...
Wolfbane Posted October 9, 2015 Share Posted October 9, 2015 Good for killing mechanical vibration. Another one of those things -- are film and foils microphonic? That's why I use oil filled caps, I don't have to worry about it, and no poo! Why not just use thick 2 sided tape between things? The good stuff comes in white, doesn't get brittle for decades and is easily removed with some bare wire if used Luca Brasi style. You could also use a knife, Sollozzo style..... Luca used to say 'never bring a knife to a gun fight'. It was the garrote that did him in. Sadly Sonny wasn't listening. Link to comment Share on other sites More sharing options...
Arkytype Posted October 10, 2015 Share Posted October 10, 2015 John, I and some other forum members have no objection to using this venue to "hawk your wares". Having said that, the one hawking their wares is fair game for praise or criticism. I won't start by criticizing your numerous grammar or spelling errors in your forum post and web site; instead let's start with how your "top-section baffle insert" is going to sound based upon your published data. There are two frequency response graphs posted under KLIPSCHORN MIDRANGE, TWEETER AND NETWORK SOLUTIONS on your web site. They are annotated as 8-23-2015 11.34.23 AM and 8-23-2015 11.40.50 AM. Both response curves show a 6-7 dB droop in the measured response between 2 kHz and 4 kHz. What gives? The B&C data sheet for the DCM-50 shows no such droop; instead, the amplitude is seen rising starting at about 2 kHz and has a 4 dB or so peak just below 3 kHz. Granted, the B&C DCM-50 was tested with a 320 Hz exponential horn. So, either the Selenium horn or your network is causing an unacceptable dulling of vocals where our hearing is most sensitive. Lee The plot below is this crossover region in question. As you can see the red plot is the horn without the network and the blue, purple and green are various topologies considered in the design. Also, not shown is how the mid and the tweeter integrate to "smooth" this response. Hmmmm... how is the tweeter's acoustic output gonna fill in the response pothole at 3 kHz? In keeping with your pledge to "...measure everything we sell and provide response plots to you.", how 'bout showing us a frequency response of the combined output of one of your two-way systems with either the Faital or K-77 HF. Quite apparent however is the dip in the response of the system without the network. I do thank you for bringing this to my attention and I will revise the webpage to make this clear. Why did you remove that plot from your website? Are you confirming that the Selenium HM3950 horn + B&C DCM50 driver exhibit the 6-7 dB droop without a network? Regarding the data sheet for the B&C. How is that applicable? My plots have the B&C on a Selenium horn and, as such, the reflections, responses etc. will not be the same. I prefer to see a driver's plane wave tube response; that way we can compare apples to apples without the influence of a horn which may not be optimized for the driver as it appears is the case for the Selenium you chose. And while on the subject of response peaks and dips, anyone that has any experience measuring horns knows that a response within about 10dB is pretty GD good! Well, maybe a 10 dB swing is pretty "GD good" for your stuff, but take a closer look at the B&C DCM50 data sheet. The frequency response is within plus or minus 2.5 dB from say 450 Hz to 6 kHz with their 320 Hz exponential horn; a 5 dB variation. Yours? Plus or minus 5 dB, a 10 dB variation. Lee Link to comment Share on other sites More sharing options...
Arkytype Posted October 11, 2015 Share Posted October 11, 2015 John, I've posted a schematic of your "autotransformer based crossover network" based upon images on your web site. Feel free to correct it. Better yet, why not post the schematic of the network you use for say the K-77 tweeter? What kind of warranty repair service are you prepared to offer your customer when they fry the voice coil in their B&C DCM50 driver? Your network has a fatal flaw in that you failed to heed B&C's specifications regarding the protection of the driver from excessive low frequency energy. It clearly states that you must use a "12 dB/octave or higher slope high-pass filter." Your network has but a single capacitor (labeled C1 on my schematic) which offers, at best, a 6 dB/octave slope. For those of you in Rio Linda, that means at 200 Hz, the B&C driver will have to absorb twice the power B&C recommends. Hey, he even brags about it by stating, "Low frequencies that would distress the midrange compression driver are attenuated by a single series capacitor..." That statement is disingenuous at best. After reading "We're not adverse (sic) to showing response plots. That's what engineers do, they measure things that guide design changes and decisions.", I thought, great! maybe ol' John will show us electrical plots of his network if I asked him nicely. Well, upon further reading on his web site, he contradicts that "show and tell" attitude by writing, " We do not publish electrical performance of networks because, to the end user, that data is really just bullshit and of no real value. It might look great but how the loudspeaker chain interprets the signals is all that matters." Next time, we'll discuss the "new autotransformer". Lee Lee Link to comment Share on other sites More sharing options...
John Warren Posted October 11, 2015 Author Share Posted October 11, 2015 (edited) The Selenium horn was selected because it's one of a few that will actually fit within the constraints of the top-section so, in some regard, it's an engineering compromise. I also was sensitive to cost. My initial target was $1500 for a complete packaged pair, I missed it but not by too much. I didn't remove any plots from the webpage, I added the one below, a comparison between the Klipschorn stock unit and the Selenium-B&C. Below about 5kHz they're similar but the similarities end there. The Selenium- B&C combinations produces far greater output levels without distress. To put it bluntly, the setup blows the stock unit away. Are the responses perfect? No. Can I eliminate that response anomaly?Yes but it will add to the package and that adder is about $200 to the overall cost. Maybe I'll add it as another network option. FWIW, I've measured a lot of horns including ones made by folks that post on this site. I've also measured the response on networks made by others. From where I'm at, this setup can compete with any of them. That said, I'd be more inclined to provide additional information to you but I really don't see the point. From the get-go you seem to have made it clear that you were really in this for a fight, nothing more. So from my perspective why bother trying to engage in a dialogue with you. Edited October 14, 2015 by John Warren Link to comment Share on other sites More sharing options...
Arkytype Posted October 11, 2015 Share Posted October 11, 2015 As ad addendum to my previous post, I've labeled the components on John's "Autotransformer Based Crossover Network" so you can more easily follow the schematic. The two "solder rails" to which the capacitors are connected are labeled as A1 thru A10 (at the top of the capacitors) and B1 thru B10. The screw terminal block is labeled 1 thru 8. Lee Link to comment Share on other sites More sharing options...
Al Klappenberger Posted October 11, 2015 Share Posted October 11, 2015 :P Link to comment Share on other sites More sharing options...
John Warren Posted October 11, 2015 Author Share Posted October 11, 2015 (edited) Your network has but a single capacitor (labeled C1 on my schematic) which offers, at best, a 6 dB/octave slope. For those of you in Rio Linda, that means at 200 Hz, the B&C driver will have to absorb twice the power B&C recommends. Hey, he even brags about it by stating, "Low frequencies that would distress the midrange compression driver are attenuated by a single series capacitor..." That statement is disingenuous at best. The B&C is capable of 80W dissipation with short term exposures to 160W. At 20W it's deafening you can't even stay in the room with it on, plenty of margin. The 12dB/oct is conservative and assumes 80W continuous 400Hz and up. We're about 1/4 of that dissipation level here and that's a maximum. Power levels are well within reason at 200Hz, no issues. Edited October 11, 2015 by John Warren Link to comment Share on other sites More sharing options...
Al Klappenberger Posted October 11, 2015 Share Posted October 11, 2015 Link to comment Share on other sites More sharing options...
John Warren Posted October 11, 2015 Author Share Posted October 11, 2015 (edited) network schematic basic.jpgJohn, I've posted a schematic of your "autotransformer based crossover network" based upon images on your web site. an hour of your life you'll never get back. Feel free to correct it. Better yet, why not post the schematic of the network you use for say the K-77 tweeter? I'm not going to correct it. You can buy one and read them or measure them yourself however. The reality is that the mod is a good one. If you wish to continue to tear into it, have at it. I however replaced the O2 sensor on my 03 Tacoma today. Edited October 11, 2015 by John Warren Link to comment Share on other sites More sharing options...
John Warren Posted October 11, 2015 Author Share Posted October 11, 2015 Well, maybe a 10 dB swing is pretty "GD good" for your stuff, but take a closer look at the B&C DCM50 data sheet. The frequency response is within plus or minus 2.5 dB from say 450 Hz to 6 kHz with their 320 Hz exponential horn; a 5 dB variation. Yours? Plus or minus 5 dB, a 10 dB variation. Add for the record, lets recall what a Klipschorn response looks like. Apparently 10dB is being generous. Link to comment Share on other sites More sharing options...
John Warren Posted October 11, 2015 Author Share Posted October 11, 2015 And I get it, smooth responses are great and preferred- Iwata 300 on Radian 950Be with TAD ET700 tweeter on custom net. The mids alone set you back $3k/pr. Link to comment Share on other sites More sharing options...
erik2A3 Posted October 11, 2015 Share Posted October 11, 2015 Sifting through some of the chaff here, it seems there was at least one reference to the use of silicone rubber/sealant as one possible choice for reducing mechanical interaction and vibration between crossover components. Although I didn't own any Klipsch until we bought our first pair La Scalas in about 2002 (when I first started posting here under what at that time was a different handle), I began building speakers and crossovers around 1990. Back then, silicone was the go-to material -- preferred to hot glue and other gunk - for its adhesive qualities and flexible yet very tough vibration control. Crossovers have no interest in aesthetics, and I had never been able to perceive any sonic compromise between the somewhat-more-homely-looking chokes I wound myself and the exceedingly more expensive (not to mention decidedly more glamorous) air cores I sometimes bought when I was too lazy to play with enabled wire, but clear silicone (applied beneath, between, and around those caps, coils, and resistors) might be a bit easier on the eyes than some other options if "easier on the eyes" is important. Link to comment Share on other sites More sharing options...
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