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Al Klappenberger

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Everything posted by Al Klappenberger

  1. 616gc, Those two drivers are direct radiators. I will bet they have higher distortion than the Khorn woofer. Mixing direct radiators and horns is not wise. Bad enough that a direct radiator woofer is usually employed. I don't think there is much need to crossover lower. You just need a bigger mid-range horn and crossover with larger parts and more loss. I found that a woofer that goes higher , like the Belle or LaScala, gives you a much better choice of top end. All you loose is some deep bass. Al K.
  2. Mark, I think the HF200 is available in 8 or 16 Ohms. I have never seen a test on the TAD low frequency performance but I wold bet it's good! They have an excellent reputation. The big price tag is what stops most of us. I just realized there will soon be a Faital Pro 204 that costs even less then the 200. It's not released yet. Al K.
  3. I think I'm throwing cold water on the fire, but look at a comparison with the K55 driver on a 1-inch horn. The HF200 wins but It's close. The K55 won't go to 20 KHz though! Al K.
  4. FYI: I just got through testing the Faital Pro HF200 driver. It's a winner and looks like to will make a clean low distortion 2-way Khorn! Look at the other thread. I think it makes the B&C DCX50 and 9 KHz crossover a moot point for a time-aligned high end. It has about 1.26% harmonic distortion at 400 Hz at 105 DB SPL at 2 feet and goes clear to 20 KHz. The IM distortion is a squeak higher than the DCM50, but not by a significant amount! Al K.
  5. US Speaker is asking $300.00 each for them. I think that's pretty reasonable! Al k.
  6. Rudy, No.. I don't plan to distribute the HF200. Dave got this one from US Speaker, I think. I haven't looked around to see where else you can get them as yet. I think it looks like the one to beat if you are wanting to go 2-way though. Al K.
  7. CALLING Mr KLIPSCH .. I THINK WE JUST MIGHT HAVE A 2-WAY KHORN FOR YOU! Here's a direct comparison of intermodulation distortion between the B&C DCM50 and the Faital Pro HF200 drivers. The B&C wins by a nose! But the extended frequency response of the HF200 makes it a clear choice! The levels were tested by using a B&K 4220 pistonphone and a B&K 4133 mike. I think the levels are accurate to 0.5 dB. The plots look a bit different because the B&C curve was scanned off a paper printout. The HF200 plot was direct off a computer screen dump. Al K.
  8. I have started the distortion tests and I AM IMPRESSED! Here's two plots. I set up the mike 2 feet from the mouth and ran the level up to 105 dB SPL with a 400 Hz tone. The analyzer computed the harmonic distortion at -38dB. That's only 1.26% harmonic distortion. Next I reduced the level need to make 105 dB at 2 feet by 10 dB and lowered the tone to 200 Hz. That is roughly what the level would be through a 12 dB / octave filter with the woofer generating the tone at 105 dB. The level out of the driver doped to 63 dB SPL with the second harmonic down about 15 dB lower. That's 17.8 % distortion but the level is so low it would not be noticed! This driver looks like a winner unless I have done something wrong! I plan to do a intermod test duplicating the condition I used on the B&C DCM50 for a direct comparison. That was with 450 Hz and 4400Hz tones. Al K.
  9. I started with the stock K500 horns in my Belles. The first change was to sit a pair of Altec 511b on top and listen. The difference was a jaw-droper! I moved to the 811b later with a 700 Hz crossover. That horn will fit inside the Belle. The bottom line is get rid of the K400. ANYHTING is better! Al K.
  10. Lee, Thanks. I didn't know that! All I knew was that it increased. I didn't realize it was to that degree! This illustrates how tough it is to go from 400 Hz to even as high as 15KHz with a single driver. I'm hoping with the right driver and network it might be possible. Al K.
  11. I connected the driver through the squawker channel of a 12 dB / octave network and set the attenuation to 9 dB. This is the response. I plan to run harmonic distortion tests with a signal into the driver at 200 Hz 12 dB below the level it takes to generate 110 dB SPL at 400 Hz. This should be similar to the Klipsch stock AK-3 network slope. The distortion generated should tell if an extreme-slope network is required. To say that another way. I will see what level it takes into the driver at 400 Hz to generate 110 dB SPL then use a level 12 dB lower at 200 Hz. The difference would normally go to the woofer. The distortion at 400 Hz while generating 110 dB SPL will tell me if this driver is usable at all. I will probably not do this until tomorrow. It will require that I use ear-plugs and my wife will be home soon and will not tolerate that sort of noise for long! Al K.
  12. JC, It's 30 Deg off center of the horn mouth. The distance is 1 meter from the driver rather then the mouth.Yes, this is a wide range driver. It will be good for 2-way operation only of the distortion at and below 400 Hz is low enough. Al K.
  13. Here's the frequency response. It looks good all the way up and looks usable below 400 Hz. The distortion down there remains to be seen though. Testing for that requires changing to my B&K mike and checking a lot of levels and other details. Stay tuned.. Al K.
  14. Here's a driver that I think has potential. It's another Italian job like the B&C. I will be doing distortion tests later, but here some frequency response testing. Al K.
  15. I received the sample Faital Pro HF200 driver a while ago. I'll be starting a new thread about it. Al K.
  16. Rudy, "Why does the spec sheet recommend a crossover of 900Hz minimum? I see it seems to be able to go well below that" This is the key to what this is all about. A lot of these drivers will specify the crossover with an asterisk * footnote. When you read it, it will tell you something like 12 dB / octave minimum filter. This is telling you that it can't handle even moderate low frequency energy without distorting. The alternative is cross it over higher with a gentle slope filter or use a steeper slop if you need to go down in frequency. The fact that it will have good response down to 400 Hz doesn't tell you what will happen when a sound at 200 Hz (an octave down) that is 12 dB down the filter slope hits it! It can even crash the diaphragm into the phase plug! Most likely it will just generate distortion consisting of harmonics that don't belong there that you can hear. Not everybody is going to run the driver down to 400 Hz with a filter that nails 350 Hz by 20 dB like my ES400. A typical 2nd order filter (12 dB / octave), the filter in the stock Khorn AK-3 network for example, won't hit 20 db until you get down to 130 Hz! That is why drivers that seem to go low in frequency really can't be used very low. They will just distort. Other drivers, like the 1-inch JBL 2426h that I use on my Belles will distort even at 400 Hz. This is what I will be testing for. It needs to be clean at 400 Hz to even be considered. That means it will operate down to 400 Hz with a better chance of handling the extreme lows. A steeper slope filter my still be required, That is the reason I recommend the B&C DCM50. It is designed to go down to 400 Hz with a 12 dB / octave filter. Al k. EDIT: I just remembered that I made up a series of overlaid computer plots showing the relationship between filter slope and how low a driver can be operated. It's below.
  17. Well..... The first candidate I plan to test is the Faital Pro HF200. Dave has arranged to have one sent to me, The spec sheet is attached. It's only rated down to 500 Hz but Dave was told it will work well down to 400 Hz. I plan to test the IM distortion. I think that is going to be the main factor in the choice. Frequency response extremes up high on it look good, but for a 3-way system with it mounted on a horn big enough to go down to 400 Hz, it's not very important! Al K. faital_hf200.pdf
  18. The B&C drivers all look like they are intended to be crossed over much higher than 400 Hz. The DE82 looks like it starts down way above 400 Hz on the official curves. Just because it's response will go that low doesn't mean it will do it without distortion. I found that out the hard way with the 1-inch JBL 2426h. I would need to test one and I think there are more logical candidates to consider first. I may have an unwarranted bias against the P-Audio driver. I think I heard talk about them being inconsistent. Al K.
  19. Thanks Dave. That driver doesn't look to bad but I am not sure the P-Audio version will have consistent quality. We need to do a serious search for good alternatives. With the ease of expanding the Eliptrac correctly down to 1.4 inch drivers the field is much more open than just 2-inch possibilities too. Here's one I think deserves a serious look at: http://www.greatplainsaudio.com/downloads/390series.pdf AL K.
  20. Guys, I did a series of test on the P-Audio K69 equivalent driver a while ago with a loaner driver. I can't remember who loaned it to me though. I don't have the results here any more either. Drat! I think I posted them here, but I can't remember that either! 64 years old an a bad case of C.R.S.! Anyhow, we need to find another driver that will handle a 400 Hz crossover. It turns out the B&C DCM50 I like is back-ordered until April with the distributor! Al K.
  21. I shouldn't have mentioned that "absorb" thing. It is relevant only to a network designer, like me. Forget I said it. The lows will be generated into your room the same way they are now, by the main speakers or the sub. Only the highs are really important to focus the center. That's how PWK got away with using a Heresy between Khorns as a center. He even had a network option for the Heresy for a while that had the highs up full. A full-range center is obviously best, that's why the Belle or Cornwall was the later preference for the center. but you don't really need the extreme lows. Al K.
  22. I'm saying you don't need the bass bin at all! A simple load resistor on the network absorbs everything below 400 Hz to keep the center amp happy. The flank speakers will make all the bass you need. Al k.
  23. Dean, I don't know. Lend me the drivers for a couple of years and I'll try it! [8-|] Al K.
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