Greg Oshiro Posted February 11, 2012 Author Share Posted February 11, 2012 I did discover that the position of my head (inches!) makes a huge difference in imaging. This makes me more interested in measuring polars.Yes - that's largely true for small-room corner horn imaging performance in my experience. In fact, it's been my experience for all speakers in small rooms - even worse for planar speakers which usually cannot be toed-in in small rooms. The K-402s have a sweet spot of about +/- 1-2 feet laterally with the room's acoustic tiles in place. Without the acoustic tiles, there really isn't a sweet spot in my room. Chris That sweet spot is significantly wider than mine. My rig *might* have +/- 6 inches. My next audio accessory might be: Quote Link to comment Share on other sites More sharing options...
mikebse2a3 Posted February 11, 2012 Share Posted February 11, 2012 K402 Horiz Polar Data Open the PDFs and magnify to see data in greater detail.. mike tn 402_hor.pdf Quote Link to comment Share on other sites More sharing options...
mikebse2a3 Posted February 11, 2012 Share Posted February 11, 2012 K402 Vert Polar Data again open and magnify for best resolution 402_ver.pdf Quote Link to comment Share on other sites More sharing options...
mikebse2a3 Posted February 11, 2012 Share Posted February 11, 2012 K510 Horiz Polar Data Open the PDFs and magnify to see data in greater detail.. 510_hor.pdf Quote Link to comment Share on other sites More sharing options...
mikebse2a3 Posted February 11, 2012 Share Posted February 11, 2012 K510 Vert Polar Data Open the PDFs and magnify to see data in greater detail.. 510_ver.pdf Quote Link to comment Share on other sites More sharing options...
Greg Oshiro Posted February 11, 2012 Author Share Posted February 11, 2012 Mike-- I'm fairly unfamiliar with the Klipsch line. What's a K510? I did a search from the Klipsch home page and got "no results". --Greg Quote Link to comment Share on other sites More sharing options...
mikebse2a3 Posted February 11, 2012 Share Posted February 11, 2012 Is the Y-axis degrees, not dB? Yes What was the measurement setup? These were supplied for us by Roy as far as setup details he would have to answere that. The plots I posted were also supplied by Roy mike tn Quote Link to comment Share on other sites More sharing options...
mikebse2a3 Posted February 11, 2012 Share Posted February 11, 2012 It's a modified tractrix horn used in the cinema line. You can see it used here on the KPT-904 and in association with the K402 on the KPT-Jubilee-535 and various others. Some running Jubs and LaScala and KPT-904 are using the K510 and K402 horns in there home systems http://www.klipsch.com/cinema-speakers?n=1 Quote Link to comment Share on other sites More sharing options...
Greg Oshiro Posted February 11, 2012 Author Share Posted February 11, 2012 Is the Y-axis degrees, not dB? Yes What was the measurement setup? These were supplied for us by Roy as far as setup details he would have to answere that. The plots I posted were also supplied by Roy mike tn I don't suppose Roy provided a Directivity Index vs. frequency plot? --Greg Quote Link to comment Share on other sites More sharing options...
mikebse2a3 Posted February 11, 2012 Share Posted February 11, 2012 I don't suppose Roy provided a Directivity Index vs. frequency plot? --Greg I've not seen one. mike tn Quote Link to comment Share on other sites More sharing options...
Chris A Posted February 17, 2012 Share Posted February 17, 2012 Measuring polars in my world means taking the device under test (DUT) and mounting it on a motorized turntable in the parking lot and making ground-plane measurements. The DUT polar behavior will depend on the size and shape of the baffle in which it's mounted. So an adapter has to be made that somewhat mimics the speaker system in question *and* readily adapts to my turntable.I am sure that the plots that I referenced were taken from anechoic data gathered in the Hope, AR chamber, with the driver+horn either placed on a turntable or simply rotated between measurements by hand, thus eliminating effects from a turntable. I would guess that the driver used was the K-69-A or the K-69, which is a slightly better driver. Chris Quote Link to comment Share on other sites More sharing options...
Chris A Posted February 17, 2012 Share Posted February 17, 2012 That sweet spot is significantly wider than mine. My rig *might* have +/- 6 inches.Let me not overstate: the range in which there is a clear "stereo effect" is what I stated; the range in which there is a centered phantom image directly on centerline is like +/-6 inches.Without the acoustic tiles, the image sounds everywhere out-of-phase or monophonic from one speaker. Chris[] Quote Link to comment Share on other sites More sharing options...
Greg Oshiro Posted February 17, 2012 Author Share Posted February 17, 2012 I've been listening in the big room for a while now and it feels better. It might just be that I can get good imaging and be further from the front wall. One thing that I can't get over is that the equilateral triangle of speaker-listener-speaker doesn't seem to hold true with these K-horns. I'm hypothesizing that the off-axis response of the speakers at the equilateral triangle listening position falls off in the upper mids and highs, so imaging suffers. I also discovered that the plant-ons (the picture-framey things) on the walls prevent a good seal with the woofer horn. Now I have to take some measurements and see what's up. It looks like I have k-horn backs in my future... Quote Link to comment Share on other sites More sharing options...
Greg Oshiro Posted February 17, 2012 Author Share Posted February 17, 2012 Let me not overstate: the range in which there is a clear "stereo effect" is what I stated; the range in which there is a centered phantom image directly on centerline is like +/-6 inches. <snip> Chris That pretty much describes what I'm hearing. <snip> Without the acoustic tiles, the image sounds everywhere out-of-phase or monophonic from one speaker. Chris I haven't started down the path of fuzzy stuff yet. What I want to do is get the speakers right from a measurement perspective first, then do room treatment. Unfortunately, I think the next step is a constant directivity top hat. I'll start with a tweeter, either a JBL 2404H or Beyma CP-25. After that we get into squawkers, which will be a big step. I've heard rumors of the K55's low distortion, so I'll have to start measuring that in addition to transfer function and polar behavior. It's going to be a long journey. Quote Link to comment Share on other sites More sharing options...
Moderators dtel Posted February 17, 2012 Moderators Share Posted February 17, 2012 I'm hypothesizing that the off-axis response of the speakers at the equilateral triangle listening position falls off in the upper mids and highs, so imaging suffers. I would think you are right with that, it's the same thing I thought when in Hope seated off to the side a good bit from center trying different models. It really gives you a different picture of each design when seated really off axis a good ways. It was not intential where I sat, more of an accident really but in a good way in the long run. Quote Link to comment Share on other sites More sharing options...
Moderators dtel Posted February 17, 2012 Moderators Share Posted February 17, 2012 Now I have to take some measurements and see what's up. It looks like I have k-horn backs in my future... It would probably be a huge help, you would still be more or less in the corner so I would guess you would keep that Khorn bass but greatly improve the overall sound, that room would sound completely different, i would think. Quote Link to comment Share on other sites More sharing options...
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