djk Posted November 27, 2011 Share Posted November 27, 2011 "What is it that gives out when you go to a higher degree of compression?" First off, I think drivers with high compression ratios sound 'hard' or 'compressed' (go figure). " Is it that the magnetic strength gives out or is the mechanics of the cone and supsension that give out?" The suspension of off-the-shelf drivers is usually too soft, and the cone not hard enough. The cone absorbs HF energy, and ends up moving side-to-side as much as front-to-back (the desired motion). "It's actually 16:1 and is using a tighter suspension so that it doesn't flex under high SPL. " The tighter suspension is a good thing. A 2" entry horn has 3.14 sq in area, so the Sd of this driver is about 50 sq in (0.0322M^2)? That would make it a 10" (nominal) basket (an 8" is about 33 sq in, or 0.0214M^2, or a compression ratio of about 10:1). "It's gonna do the higher frequencies so much better than the 12" midbass it's replacing." I don't know what the driver was like. Many 12" drivers can out perform an 8" driver in a horn. Depends on how said driver is constructed. "My last horn used a lighter compression ratio than the design wanted based on your comments Dennis, and that is one of the few things I regretted. " My remarks are based on models in Hornresp and listening. In general I don't like the sound of high compression ratios, period. "Newer drivers designed for horn loading are so much better these days because they've been engineered to address some of the shortcomings. I'm not saying it couldn't be better, but such blanket claims are ignorant of everything happening within the design." That sounds insulting, I hope you didn't mean it that way. *********************************************************************** The Dunning–Kruger effect is a cognitive bias in which unskilled people make poor decisions and reach erroneous conclusions, but their incompetence denies them the metacognitive ability to recognize their mistakes.[1] The unskilled therefore suffer from illusory superiority, rating their ability as above average, much higher than it actually is, while the highly skilled underrate their own abilities, suffering from illusory inferiority. Actual competence may weaken self-confidence, as competent individuals may falsely assume that others have an equivalent understanding. As Kruger and Dunning conclude, "the miscalibration of the incompetent stems from an error about the self, whereas the miscalibration of the highly competent stems from an error about others" (p. 1127).[2] The effect is about paradoxical defects in cognitive ability, both in oneself and as one compares oneself to others. Dunning and Kruger were awarded the 2000 Ig Nobel Prize in Psychology for their report, "Unskilled and Unaware of It: How Difficulties in Recognizing One's Own Incompetence Lead to Inflated Self-Assessments". Quote Link to comment Share on other sites More sharing options...
djk Posted November 27, 2011 Share Posted November 27, 2011 "What is it that gives out when you go to a higher degree of compression?" First off, I think drivers with high compression ratios sound 'hard' or 'compressed' (go figure). " Is it that the magnetic strength gives out or is the mechanics of the cone and supsension that give out?" The suspension of off-the-shelf drivers is usually too soft, and the cone not hard enough. The cone absorbs HF energy, and ends up moving side-to-side as much as front-to-back (the desired motion). "It's actually 16:1 and is using a tighter suspension so that it doesn't flex under high SPL. " The tighter suspension is a good thing. A 2" entry horn has 3.14 sq in area, so the Sd of this driver is about 50 sq in (0.0322M^2)? That would make it a 10" (nominal) basket (an 8" is about 33 sq in, or 0.0214M^2, or a compression ratio of about 10:1). "It's gonna do the higher frequencies so much better than the 12" midbass it's replacing." I don't know what the driver was like. Many 12" drivers can out perform an 8" driver in a horn. Depends on how said driver is constructed. "My last horn used a lighter compression ratio than the design wanted based on your comments Dennis, and that is one of the few things I regretted. " My remarks are based on models in Hornresp and listening. In general I don't like the sound of high compression ratios, period. "Newer drivers designed for horn loading are so much better these days because they've been engineered to address some of the shortcomings. I'm not saying it couldn't be better, but such blanket claims are ignorant of everything happening within the design." That sounds insulting, I hope you didn't mean it that way. *********************************************************************** The Dunning–Kruger effect is a cognitive bias in which unskilled people make poor decisions and reach erroneous conclusions, but their incompetence denies them the metacognitive ability to recognize their mistakes.[1] The unskilled therefore suffer from illusory superiority, rating their ability as above average, much higher than it actually is, while the highly skilled underrate their own abilities, suffering from illusory inferiority. Actual competence may weaken self-confidence, as competent individuals may falsely assume that others have an equivalent understanding. As Kruger and Dunning conclude, "the miscalibration of the incompetent stems from an error about the self, whereas the miscalibration of the highly competent stems from an error about others" (p. 1127).[2] The effect is about paradoxical defects in cognitive ability, both in oneself and as one compares oneself to others. Dunning and Kruger were awarded the 2000 Ig Nobel Prize in Psychology for their report, "Unskilled and Unaware of It: How Difficulties in Recognizing One's Own Incompetence Lead to Inflated Self-Assessments". Quote Link to comment Share on other sites More sharing options...
Wardsweb Posted November 30, 2011 Share Posted November 30, 2011 While the sound is the same, the esthetics can be improved for home use. These are factory built using double sided South African mahogany cabinet grade plywood (a one time deal they won't likely repeat). The grills I made and are held in place with magents embedded in the frame and cabinet. The next phase will have the horns painted in an automotive finish. Quote Link to comment Share on other sites More sharing options...
Panacea Engineering Posted November 30, 2011 Share Posted November 30, 2011 Your Jubes look fantastic... I'm certainly glad that I am not the ONLY SAE fanatic in the world. I have truly used and enjoyed your site over the years.....! W. C. Quote Link to comment Share on other sites More sharing options...
seti Posted November 30, 2011 Share Posted November 30, 2011 From what I remember PWK was talking about an earlier incarnation of the K510 a k510 prototype when said he wanted a larger one. This was also the horn that Roy showed PWK what the modified tractrix could do. The k403 is an interesting horn as you see PWK and Roy's hand in the creation. It is modified tractrix ala Roy with collapsing verticals as we see in all PWK horns. The k403 sounds and measures great. PWK and Roy did a great job on it. It could only be considered small next to the k402. It is a good sized horn still. Quote Link to comment Share on other sites More sharing options...
kaiser SET say Posted November 30, 2011 Share Posted November 30, 2011 While the sound is the same, the esthetics can be improved for home use. These are factory built using double sided South African mahogany cabinet grade plywood (a one time deal they won't likely repeat). The grills I made and are held in place with magents embedded in the frame and cabinet. The next phase will have the horns painted in an automotive finish. Gorgeous Luther, I'm thinking a nice matallic blue to match those amps would look so Euro. Then we would have to get those bass bin grills in black and Trav may never go for that. Maybe green cloth and that awesome Canary yellow I spoke of for the 402's. Be the brightest Sunflowers in town[] Quote Link to comment Share on other sites More sharing options...
6foot8 Posted December 1, 2011 Share Posted December 1, 2011 I believe the Jubs in Chattanooga are an active 3-way system... Quote Link to comment Share on other sites More sharing options...
Chris A Posted December 1, 2011 Share Posted December 1, 2011 Welcome back, Big Man...How are those Jubs doing? Chris Quote Link to comment Share on other sites More sharing options...
6foot8 Posted December 1, 2011 Share Posted December 1, 2011 Hey Thanks, it has been a while since I have been here. They sound great, still enjoy them as much as ever. Looks like the list of owners has grown quite a bit since I was last here. Quote Link to comment Share on other sites More sharing options...
Chris A Posted December 1, 2011 Share Posted December 1, 2011 Yes [], it has. Word-of-mouth kind of gets around... Chris Quote Link to comment Share on other sites More sharing options...
6foot8 Posted December 1, 2011 Share Posted December 1, 2011 Chris, I was wondering if anyone that you know of has the EQ settings that Roy gave to some forum members for the Jubs. I, like many folks here, spent a long time tuning and tweaking my set to get a balance that was consistently satisfying. I finally stumbled on an article about equal SPL contour lines across the frequency spectrum. I was previously unaware that our hearing was significantly different with respect to frequency (other than the normal rolling off of the extreme low and high fequencies) and subsequently found out that my hearing was significantly different in a few frequency bands than "normal" or the ISO standard. I discovered an online site that produced an equal hearing contour line based on an interactive test. I was amazed at what I found. So based on the results of that test I made some changes to my EQ settings and it made all the difference. My EQ curve looks very different in a couple of the bands than "typical." What I did was compare Roy's Freq\SPL data to that of the test results using 1KHtz as the reference point and calculate the difference. For example, if my hearing at 3KHtz is plus 8 (from the reference) and the speaker is minus 2 then I adjusted that band down 6dB to be flat to the reference. Not sure if this is something anyone else has tried of it it even makes any sense but the results I achieved were very favorable. However, this data from Roy was measured in an anechoic room and I was estimating the numerical SPL at each frequency from the chart, not a table of data. If I had his actual EQ adjustments I could see how that compares to the adjustments I have made based on the charts and my hearing test without the aide of a real time analyzer. It sounds very good to me but I am very curious as to how my adjustments compare to his or other forum members. Quote Link to comment Share on other sites More sharing options...
Wardsweb Posted December 1, 2011 Share Posted December 1, 2011 Gorgeous Luther, I'm thinking a nice matallic blue to match those amps would look so Euro. Then we would have to get those bass bin grills in black and Trav may never go for that. Maybe green cloth and that awesome Canary yellow I spoke of for the 402's. Be the brightest Sunflowers in town Right now the color is leaning more towards a burgundy similar to my MC240. Quote Link to comment Share on other sites More sharing options...
Chris A Posted December 1, 2011 Share Posted December 1, 2011 Eric, you have a PM. Chris Quote Link to comment Share on other sites More sharing options...
6foot8 Posted December 1, 2011 Share Posted December 1, 2011 Chris, Thank you very much. Eric Quote Link to comment Share on other sites More sharing options...
kaiser SET say Posted December 1, 2011 Share Posted December 1, 2011 Gorgeous Luther, I'm thinking a nice matallic blue to match those amps would look so Euro. Then we would have to get those bass bin grills in black and Trav may never go for that. Maybe green cloth and that awesome Canary yellow I spoke of for the 402's. Be the brightest Sunflowers in town Right now the color is leaning more towards a burgundy similar to my MC240. I see what you mean, I'm with you it's out with the SAE blue and Sunflower yellow and in with the '32 Duece Coupe Burgundy[] So gonna run the tops tube and low end solid? By all the listening we've done on them down in Hope I always though leaving strong solids on the bottom would give that quick thump/transient recovery and tube tops decay to die for[] Quote Link to comment Share on other sites More sharing options...
Coytee Posted December 1, 2011 Share Posted December 1, 2011 Hey Thanks, it has been a while since I have been here How's it going! I've moved mine to FL.... I guess I needed to replace your missing pair down here so FL could keep a head count. [] Quote Link to comment Share on other sites More sharing options...
6foot8 Posted December 2, 2011 Share Posted December 2, 2011 Hey Coyote, It's been a rough couple of years for us but we are hanging in there. Wasssup with the move to Florida? Quote Link to comment Share on other sites More sharing options...
Wardsweb Posted December 2, 2011 Share Posted December 2, 2011 I see what you mean, I'm with you it's out with the SAE blue and Sunflower yellow and in with the '32 Duece Coupe Burgundy So gonna run the tops tube and low end solid? By all the listening we've done on them down in Hope I always though leaving strong solids on the bottom would give that quick thump/transient recovery and tube tops decay to die for The advantage of the DX-38 is bi-amping these. The bottom end does well with a lot of extra power on tap. While the horns need very little. Tubes and horns have always been the sweet spot for me. Quote Link to comment Share on other sites More sharing options...
Coytee Posted December 2, 2011 Share Posted December 2, 2011 Wasssup with the move to Florida? Changed firms. Wife is still in Knoxville area (Greenback). I'm heading up that way this next Thursday. I'll toot my horn as I drive through Chattahoochie. Quote Link to comment Share on other sites More sharing options...
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