sunnysal Posted July 6, 2004 Share Posted July 6, 2004 o.k. how about this...let's say I find some 290 drivers and 311 horns (or jbls, etc.)...I build the top hat and get it all together. I am thinking why not "go all the way" and try to fix the last remaining issues that I (or anyone else for that matter) have with the k-horns...the time and phase issues between the drivers on the klipschorn. why don't I buy a DBX driverack 480 electronic speaker management system (http://www.dbxpro.com/ftp_mirror/PDFs/Spec_Sheets/480CutSheet.pdf), this allows me to select crossover points and slope (up to 48db/octave) in butterworth, bessel or linkwitz. (the behringer DX2496 has the same feature set but some people over at AA mention it is noisy and we know that we cannot have ANY noise or it will show up storngly on the k-horn). Most importantly it allows me to add delay to each output (driver). So I triamp the sucker (my PWM amp for the tweeter, my 2A3PP for the mid horn and my dynaco mkIV monoblock for the bass) and add about 1.7ms delay to the mid horn and about 8ms to the bass (these based on the tests run by richard heyser in 1989). If I run mucho slope on the crossover (as al k has suggested and I think is a good idea) and get the time delay from driver to driver corrected should I not have the ultimate k-horn? the unit also allows phase compensation by driver but I am not sure what is needed there. first: am I nuts? and why? second: what are the issues that stand in the way of a perfect k-horn, have I got them straight? third: any opinions about the equipment mentioned? thanks, tony Quote Link to comment Share on other sites More sharing options...
D-MAN Posted July 6, 2004 Share Posted July 6, 2004 Sunnysal, Pretty much all good ideas, I am not familiar with the electronic crossover you mention. The delay length imposed by the bass bin to the midhorn driver diaphragm is certainly less than (approx.) 54 inches (cone to cone, as it were). At 1100 ft per sec. what the actual delay time is I will leave to you... Theoretically, it falls into the range at which the delay it could be discernable by the listener (about 3 ft if I remember correctly). But then that is actually the treble end of things (or higher frequencies) than what is being produced by the bass bin (400Hz and below)... The difference in distance between the midrange and tweeter diaphragms is quite a bit less than 3 ft and that range of frequencies is where the rubber meets the road in noticable time delay anyway and is not discernable by the human ear. I would say go for it on the basis of perhaps gaining a relatively notchless frequency range coverage rather than the (bonus) time-delay correction. The use of electronic crossovers is recommended in some circles as a means to better avoid the insertion losses and frequency notching reportedly associated with passive crossover networks. The reported benefits allow for a more-direct or unaltered "damping" of the amp to the speaker(s). The drawback is that it also means that you have more gear to plug in to the wall and in your case, the added problem of multiple amps and there respective outputs. Things like additional volume controls in the signal path have to add losses as well as decreasing the signal-to-noise, etc. I've read that some theatre setups maintenence personnel recomend the electronic crossover methodology over the passive ones, but the point made seemed relatively unconvincing to me. It came of as a personal preference rather than citing any reasonable scientific references. So at this point, I don't really have any conclusion... I would look primarily at the costs involved. If the cost of a "good" electronic crossover exceeds that of a "good" passive one, then... If you do it, please post your results, I'm sure that there are those here who are quite interested as I am... DM Quote Link to comment Share on other sites More sharing options...
sfogg Posted July 6, 2004 Share Posted July 6, 2004 Why not go full bore and go with the DEQX box for the crossovers? It can do up to 300db/octave crossovers (which would make the time alignment between drivers pretty much irrelevant but it can do that too) as well as general speaker correction. http://www.clarityeq.com/ If they had a three channel version...... Shawn Quote Link to comment Share on other sites More sharing options...
sunnysal Posted July 6, 2004 Author Share Posted July 6, 2004 yup that's the ticket! that unit also adds much of the Tact feature set! wow, triamp with that sucker and heads will roll! I wonder what it sounds like and when it will be available (if ever)? regards, tony Quote Link to comment Share on other sites More sharing options...
sfogg Posted July 6, 2004 Share Posted July 6, 2004 " I wonder what it sounds like and when it will be available (if ever)? " I'm pretty sure it is available now. NHT is using a variant of it in their upcoming DSP speaker. Shawn Quote Link to comment Share on other sites More sharing options...
sunnysal Posted July 6, 2004 Author Share Posted July 6, 2004 I checked with them, nothing shipping for sale to consumers. but they have produced OEM stuff for NHT, though you cannot buy the NHT stuff yet, they just annouced it and showed some pictures. Remember NHT annouced this stuff originally two years ago! you know how this works...in software it is called "pre-announcing", cynics call it "vapor-ware". But I have offered to be thier rep in central america and I truely hope they ship something soon. I will keep you updated on them, tony Quote Link to comment Share on other sites More sharing options...
Deang Posted July 6, 2004 Share Posted July 6, 2004 Once you give up on the drivers and horns, and change them -- they aren't "Klipschorns" anymore. As an advid listener to the "time aligned/phase arrayed" Dahlquist DQ-10 for the better part of a decade -- it's my opinion that dealing with those issues is like chasing a tail. 3ms between the midrange and tweeter? Just make sure you don't move your head an 1/8 of an inch in any direction while you're listening. Also, any "corrected" delay issues are lost after 1st and 2nd order room reflections have their say. It does sound like fun having all that gear to mess around with, and I suppose if you can ever manage to get things set right -- it'll sound dynamite. Quote Link to comment Share on other sites More sharing options...
khorn58 Posted July 6, 2004 Share Posted July 6, 2004 just rember the dbx driverrack converts all audio to digital before cossing over the signal ect. i have one for my big pay. it ok when i am in a hurry and want a ok stereo 3 way cross over. but when i want that anolog punch I just would use it at all. I think a tru anolog crossowver made with high quitly parts would be nice for khorns. the old aAhley crossowvers can be modified for cheap with beter parts for good hifi sound. To me any many other modern dbx is crap. They made some good stuff back in the 80,s. but nother new I like. the old dbx compresser were nice and still are but even they cant reprodusce somthing close. Quote Link to comment Share on other sites More sharing options...
WMcD Posted July 6, 2004 Share Posted July 6, 2004 It will be a monumentous experiment. In theory, you delay the tweeter and mid so get it back in time delay to the woofer. Get all acousitic responses equal. Then, sitting in your easy chair there will be a switch to check the time aligned response versus the raw response. It could be magic. Please invite us over. We'd all like to know for sure. Gil Quote Link to comment Share on other sites More sharing options...
sunnysal Posted July 7, 2004 Author Share Posted July 7, 2004 that is the point, it may just be chasing my tail BUT...I keep remembering john curl and others berating me for keeping my k-horns when they were so convinced that the time alignment/phase issues outweighed the positive aspects of the speakers. this all started when I decided that upgrading the drivers seems like a worthwhile pursuit, if I do this I will need a new crossover... hence consdering an electronic crossover instead of a passive crossover, primarily for the ability to select (and vary) slopes, crossover points and modes without all that component swapping. Installing an electronic crossover opens the possiblity to time and phase correction. (a neighbor here has a system with TacT room correction installed and I can tell you it works wonders in his already very nice system). I come back to the question...what needs to be done to improve the k-horn? improved high and mid drivers? (I have already decided there is room there for improvement) time align/phase correction? The results may be modest or they may be revelatory, I do not know, hence the fishing for opinions. many of you guys have experimented with improving your k-horns. regards, tony Quote Link to comment Share on other sites More sharing options...
Q-Man Posted July 7, 2004 Share Posted July 7, 2004 Tony Some people just can't leave well enought alone! I don't understand you guys. The 290/311/JBL-2404H tweeter and Johns network isn't a modest improvement like you said. It's more of a night and day one. An active crossover is a good way to start, you can make adjustments on the fly. But, if you get the drivers and horns listed above then Johns network would do you fine. Remember the bugs are all ready worked out of this mod. I think once you hear these things you will forget all about the time alingment issue, maybe not? If your like me, once you get something in your head you have to try it. AK-4, They might not be Klipschorns anymore, but to me they still are. To me Klipschorns are all about the bass horn. Quote Link to comment Share on other sites More sharing options...
dubai2000 Posted July 7, 2004 Share Posted July 7, 2004 Tony, interesting question you have brought up. Having three amps at my disposal, I am tempted to triamp my Khorns as well. A friend of mine has got himself a Behringer CX3400 crossover and he is quite impressed with the unit. He also uses high efficiency speakers and has not complained about too much noise. For the price these units sell over here (Eur 140), it's probably worth experimenting. My friend's initial listening reports are very positive. Like others posting here, he is impressed by the added clarity of the sound and finds it difficult to listen to his upstairs system (a pair of Heresys) which sounds kind of 'clogged up' in comparison. I am hoping to audition his active system soon....it might indeed be a revelation. What bothers me, though, is losing the distinct (and cherished) characteristic of each amp, but perhaps this concept is all wrong anyway!?! Perhaps reproduced music becomes so clear (difficult to imagine an upgrade to Khorns in that respect, but diifferent horns/drivers indicate that upgrades are possible!) that the question of amp characteristics will be totally irrelevant. Wolfram Quote Link to comment Share on other sites More sharing options...
sfogg Posted July 7, 2004 Share Posted July 7, 2004 Tony, " when they were so convinced that the time alignment/phase issues outweighed the positive aspects of the speakers. " I can't speak for the K'Horn but on LaScalas I can certainly say that moving from a first order crossover to Al's extreme slope model (around 150db/octave) made a very nice difference in clarity through the vocal range. I'm assuming this is because I no longer have two drivers (that are not in alignment/phase) trying to reproduce the same material which was causing interference effects. Now the otherlap of each driver where they aren't more then 10dB down relative to each other is only about 50hz wide. As such time alignment/phase at the crossover point is much less important since the drivers are barely interacting with each other anyway. If you were near me you would be welcome to come hear them once I finish my dedicated room. Personally the part of the DEQX that interests me the most is its ability to have very high order crossovers. The extra correction it can do is just gravy. Shawn Quote Link to comment Share on other sites More sharing options...
Q-Man Posted July 7, 2004 Share Posted July 7, 2004 Maybe it's because I'm a speaker tweaker, but I believe you first should make the speaker all that it can be before you concern yourself with amps. I don't mean to change the subject, but the University Classic bass horn is cleaner sounding then the Klipschorn, but needs one heck of a good subwoofer because it doesn't go as low as the Klipschorn. This may be a project that needs to be brought up to date. I can't help to think that this might be the end all speaker with a new top end designed for it. But, one thing at a time. Quote Link to comment Share on other sites More sharing options...
sunnysal Posted July 7, 2004 Author Share Posted July 7, 2004 well, q-mans last comment opens up another can of worms. the k-horn bass is certainly the star of the show BUT there is still some bass range not plumbed (namely 18-38hz) so new bass cab or not there is room to shoehorn in a subwoofer...I have no room in my house for a folded (or any other horn-based) bass horn that goes to 18hz SO my only option would be something like the new Velodyne DD-15... first things first; 1st, I must find some 311s and 290s (or jbl equivalents, though the jbl horn is too big to use in a top hat), then I must find some used 2404Hs at a reasonable price (why but altec cheap and pay full/new price for jbl?). then decide on crossover, if I go for electronic I WILL buy something that allows time delay and phase adjustment by driver, it would seem silly to leave that feature out once I go electric. dean, I don´t feel like I am insulting the k-horn, I love mine. but I am aware that there are better drivers out there than the ones placed in the current k-horn, so if I want to improve the k-horn replacing the drivers with better performing units... also, I know there has been a lot of controversy regarding time alignment and phase issues but (PWK would say drivers could be feet out of alignment and the difference would not be audible), as I said after corresponding with a few audio engineers I trust and reading a little about the subject, both in popular literature and industry literature, I have decided that nothing can be hurt by trying to time and phase align the first arrival of signals from different drivers to my listening position. This is technology that is just arriving in the consumer market place from TacT, DEQx, Rivas Audio, Velodyne, NHT, etc. but it has been used in pro audio for years now. I am fully aware that other reflections can and will arrive in many multiples, from many directions. I will be trying this out, even if I do not mod my k-horns. wolfram, if the electronic crossover is transparent enough I should still hear the character of each amplifier, I will potentially be removing several items from the signal chain, my preamp, my outboard DAC, the passive crossover, I suspect I may get more of the sound of the signal and amps. what it brings to my mind though, is perhaps all these efforts should be matched by six channels of amplification with the minimum possible charater of their own...LOL...four channels of low power tripath and two of high power tripath? they were extremely clean and detailed, low distortion and noise amps. I will probaly wait to hear the results of the other changes before deciding on new amplification. thanks to everyone for your input, I suspect this may take me a while to pull together but I will keep y´all informed. (q-man and john will be pestered with questions no doubt constantly, LOL) warm regards, tony Quote Link to comment Share on other sites More sharing options...
sfogg Posted July 7, 2004 Share Posted July 7, 2004 "I know there has been a lot of controversy regarding time alignment and phase issues but (PWK would say drivers could be feet out of alignment and the difference would not be audible)" He might be right if the slope of the crossover is high enough. If it isn't then this would be audible because the difference in phase between the two drivers is going to alter the FR of the blend between the two. It isn't so much the absolute phase you are hearing, it is the changes to the FR of the system from the interaction of the drivers. This is easily audible. Play pink noise on one of your K-Horns. Move up and down vertically standing a few feet in front of one. Notice how the noise changes? That is from the interference between drivers. Your moving vertically is changing the relative path length to your ears between each driver and it is audibly impacting the FR because of the drivers interfering with each other. At your listening position what you hear is a composite of the direct sound from the horns and the reflections from the room. If your off axis response is being screwed up because of driver interference this will impact what you hear even when seated in the prime on axis listening position. Because most horn loaded speakers have different path lengths from each driver to the listener the driver interference happens on axis too. Try playing a 400hz tone through just your midrange horn. Then switch to playing that tone through your speaker and its crossover. Listen to how that tone has change on axis as it is now being reproduced by both your mid-horn and your bass horn. Or if you do it at lower listening levels try pink noise through the mid-horn then through the mid-horn and the woofer. Try and ignore the increase in bass of course but listen to how the tone changes between the two based on the lower end of the noise the mid-horn was reproducing itself. The higher the slope of the crossover the less interaction there is between drivers so the smaller the area these changes occur in. Shawn Quote Link to comment Share on other sites More sharing options...
Q-Man Posted July 7, 2004 Share Posted July 7, 2004 Tony, I have an extra pair of JBL-2404H tweeters that I'm going to put on ebay in a few weeks along with some other stuff. I will sell them for $250.00. New they are $550.00 to $590.00. They arn't a matched pair, the disconnects are different on the back. They work fine and I could take a picture of them for you if you are interested in buying them. No big deal if you don't want them, they will sell easy on ebay at that price. I need to do some house cleaning. Quote Link to comment Share on other sites More sharing options...
sunnysal Posted July 7, 2004 Author Share Posted July 7, 2004 matching not important as long as they are both "matched" operationally, can I pay you via western union payments (results in western union moneygram to you house)? I will be bidding on the 311-60s on ebay too...though I am worried about finding 290 drivers...thanks, tony Quote Link to comment Share on other sites More sharing options...
Q-Man Posted July 7, 2004 Share Posted July 7, 2004 I don't care how you pay. You can even wait untill you find or get the other stuff if you want. I will hold them with just your word on it. This isn't ebay, this is the Forum. I think we should be able to trust each other here. Email me if you want to work out the details, include your address so I can figure out the shipping. Quote Link to comment Share on other sites More sharing options...
sunnysal Posted July 7, 2004 Author Share Posted July 7, 2004 great! you have pm! tony Quote Link to comment Share on other sites More sharing options...
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