capo72

It is my plan to use this midhorn/driver combo to crossover at approx 300 hz. It all really depends on what kind of results I get from my DR bass bin. It may sound like $hit having the mid driver playing that low, but I want to hear it for myself. I think having more of the vocal range covered by that big phenolic diaphragm is going to be a good thing. I do not own k-horns, but my understanding is one of their flaws is the bass bin's inability to play well up to the 400 hz crossover point. If that is true would this horn/driver not be a good solution? My thought as a DIY'er is anytime we can extend the frequency range of any driver to tweak crossover points, why not try it. you may hit on something eventually, right? You are likely to solve a problem by being unconventional and determined as you are by being brilliant. I'm very rarely brilliant so I have to take the other route which generally involves alot of trial end error, and i'm fine with that as long as I learn something from my errors. Jeremy

Dean, do you know if that can be done on the PCB or do you need to build a bread board to fit a 68uF Solen in there? Thanx, Jeremy

I would love to see someone develop an Extreme Slope Network for the Cornwall II's. I have always wanted to build Al K's design for my Cornwall I's, but I just do not listen to them as much as I listen to my Cornwall II's. Cornwall II ESN is something I would be very interested in. Jeremy

I had the problem with mine and my wife's both. All you had to do was let the battery run out then wait a day for the calender to get caught back up and then recharge and everything was back to normal. I can't believe how many people freaked. It was like it was the end of the world if they did not have their Zune's. IMO if you can't go a day without it then you have bigger problems. Jeremy

I'm really pleased with your results. It is all I had hoped for. My plan for these drivers on my horns is to cross them over at around 300hz to JBL 2245H in a 12 cu. ft. ported bass reflex enclosure. On top I plan to crossover at around 4500hz to Bob Crites CT 125 tweeters. I still need to finish the enclosures and design a passive network. I would like to use an extreme slope design, but have no experience with that yet. Anyway the results you have posted have solidified my confidence in my driver selection. And this horn design should be the cat's a$$ with that JBL 2482 driver. I am impressed with the off axis plots. I expected worse. I'm never too concerned with off axis results for my listening room and habits. Again thanx a ton for doing this jc. Jeremy

Looks like you dig the LFE []

Yes jc I did it the way you explain. Knowing the height of the cross section at any given point allows you to compensate the width (curve) to get the correct area. I'll dig out my paper work tonight and see exactly what I did. It's been well over a year ago since I did the layout. I'm going to try to plot some curves from the calculator via Autocad today and then i'll compare them to what I did by hand. But I agree with you that the curve (width) should be plotted based on the area with a known height and constantly adjusted to remain tractrix from the throat to the mouth. Jeremy

Thanx Edgar, I guess I don't need to draw this up now. What you've shown proves Greg's point. So is this not accounted for in the calculator? I guess not according to Bruce's conversation with Erik. I'll see if I can run some new curves and compensate for the stretch and plot them out. I had other plans for this long holiday weekend, you guys have screwed that up [] Now I'm going to have to get back to the shop. BTW I sent jwcullison a JBL 2482 driver to test on the horns GotHover built. It will be interesting to see how this horn tests. If it tests well and sounds good, then are we wasting our time here? Jeremy

When I get home tonight, I will stick my wood template inside my horn to see how it matches up. I understand where you are coming from. I think that because we sand the edges of the top and bottom back square to the sides we have the same curve although it may be shifted back toward the mouth. I would really like to draw this stuff up 3-D to test some different ideas, but my boss just gave me a big design project, so my free time at work is going to be at a minimum for the next few weeks. Jeremy

I understand the point you are trying to make, but I think you are only taking into account one factor of the expansion, the curve. I always look at the tractrix expansion as an area measurement. The square throat being 0, at any givin point away from 0 and toward the mouth you should be able to take an area measurement (cross section) and verify a true tractrix expansion. Since the top and bottom expansion is fixed because of its constant angle, only the side to side (curve) can be changed to correct the area at any given point. When checking the width dimension of the area you would be using a point on the curve you layed out straight across to the midpoint of the curve on the other side. I'll see if I can draw something in my 3-D design software to illustrate what I mean. You are correct in thinking that the curve we plot is in the middle of the curved side, but its purpose is to set a horizontal width for an area measurement that calculates out to a tractrix expansion. When you draw a tractrix curve as you have shown on your template, then you tip it at the angle needed for vertical expansion and redraw by tracing your curve with a fixed vertical pencil, as I assume you have done on your piece of wood, you no longer have a tractrix curve as the area has increased in the horizontal axis of your area measurement. Hopefully i'll have time today to draw up what i'm trying to explain. I hope this all makes sense. I think you raise a point that is confusing for many people, so my intent is trying to explain my take on this, not to prove you wrong Greg. I respect you talents and can't wait to see what you come up with for a horn. BTW, as an engineer, this is the part of the hobby that I enjoy. Jeremy

Not much to tell yet. GotHover built some of these horns and sent one to JWCullison for some testing. You can read about it in his thread about 2" 223 HZ Tractrix horns. I just sent him one of my JBL 2482 drivers to do some testing on that horn. He should be getting it tomorrow and probably have some results within a week or so. I have some testing equipment, but have had no success getting good data. I gave up for a while but the fire has been relit recently. This project has moved down the priority list for me, but I may get back to it soon. I just need to figure out how to add a few more hours to the day. Jeremy

fini, you are killing me! I almost fell out of my chair! Jeremy

My system always sounds better after the tubes warm up, and then even better after i've finished a Beefeater martini. Jeremy

I will gladly split the shipping cost with you since you are willing to do this. These things must weigh a good 30 lbs. Send me a pm with your info and i'll try to get one off to you tomarrow. Thanx for doing this. I really need to get back to my speaker project. I've got the wood about 90% cut and one speaker is clamped up. Jeremy

I have scanned my graph paper plot and printed out copies full scale. I could mail copies to someone who might want to work off my plot. Mine is done in mm and has hundreds of points. I also could do an Autocad plot when I get back to work Monday. Jeremy

I don't know if you have seen it or not before Greg, but I have attached a link to the thread I posted when I went through this build. I think you should be able to see the way I handled a couple of the questions you are dealing with. Your skills are way beyond mine so this should be no problem for you. http://forums.klipsch.com/forums/t/93132.aspx Jeremy

When I first learned you were testing these horns for Gothover, I was thinking I should send you mine as well for comparison. Not you've got me thinking I should send you one of my horns and a JBL 2482 driver. They are supposed to reproduce pretty well down to 300Hz with the phenolic diaphrams. Let me know what you think. Jeremy

Man those RB-75's sure got around! Glad they found a good home with you Jim, and you're enjoying them. I miss them every once in a while. They do alot of things right. Here is a pic of my sweet sounding Pioneer SX-650 that I refurbed. Jeremy

This is a project i'm very familiar with. You have done a good job. I too am anxious to see the test results. I have never got around to using or testing mine. Maybe one of these days Jeremy

I have the same issue and didn't realize until Mark's post, that the phono stage does go through the V4. Now that I know that is most likely the problem I may send it for the 6H30 upgrade. I need to get the cream option anyway after I stepped up to a Zu DL-103. Can you add the remote to a 1st gen BBX Mark? If so I really need to send her off for an update! Jeremy

Dern it! I recently paid $269 for a Zu 103. I should have waited and purchased the 103R for $30 more. Oh well, If I wait fir the best price, i'll be waiting forever. Jeremy

Beautiful grain, very nice sheen, a very good score indeed. I would argue that you have one of the best man caves on this forum, Pete. If you ever decide to get rid of these Corns, put me on the list. That is some of the nicest walnut grain I have seen! Jeremy

I never had any problems with ours. Maybe everything is backwards since you are "down under." The toilets flush in the opposite direction below the equator right? [] Jeremy

Definatley got to keep those Acids separate []

CAO-gold CAO-America CAO-Sopranos "The Boss" Hoyo De Monteray-Excaliber Oliva-V Arturo Fuente-Grand Reserva Ashton-(Some Maduro) Rocky Patel-(can't remember) Cruz Real Cohiba-(Dominican & Cuban) Helix-(Love those Conneticut wrapers) Te Amo-(Another nice Mexican brand) I'm sure i'm missing a few, this is just from memory. Jeremy