kwingylee Posted July 24, 2011 Share Posted July 24, 2011 Well, I want to give everyone an update on my efforts to get my Jubilee clone monsters to sound similar to my Harbeths. My initial effort included using a highly damped ALTEC 511B with the 808-8B drivers biamp using EV/DX38. This was covered in another thread. Dr. Who did magic balancing them with the horns configured vertically (similar to some current JBL models). He did a fantastic job and the system had wonderful mids. But they did not image the way I am accustom to (especially depth) and the extreme highs and transient response were lacking somewhat. I tried solving the HF problem by swapping the 808-8B with a TAD TD2001. The highs are better but I simply cannot get this combination to sound right. Way to much SSSSSSSSSSSSSSS and the imaging shortcomings persist. Just for a point of reference, my other speakers are Harbeth M40s and Newform R645s: both image spectacularly. I have the same concerns when I heard Klipsch manufactured Jubilees with the K402 horn. They created excellent lateral image but little depth. Then someone from the Chicago horn club loan a set of JMLC350 LeCleac'h horns with JBL 2435HPL drivers attached, and suggested I use a simple 6dB slopes on the DX38. This kind of make sense because Bruce Edgar in one of the interviews he gave, suggested that 6dB/Oct filters sound the best with horns and that Paul Klipsch learned the same years earlier... I figured its worth a try and set the crossover point at 920Hz. I also like the fact that the horn is circular, can go down to 350Hz and much thought has gone into reducing reflection at the horn mouth. The results far exceeded my expectations. My system now has depth in spades..... I will be staying with this combo for a long long time. The person that loan me the horns and drivers, the check is in the mail... This horn is at the moment for me, the best one to use with the Jubilee bottom. I do ultimately want to go to a passive. I got the sound I wanted with all of the HF horn equalization removed. With a 6dB slope, all I would need is a 20uF capacitor.....maybe I can do down to one amplifier. A rebuild BAT VK60 is driving the top. Kwing Quote Link to comment Share on other sites More sharing options...
mark1101 Posted July 25, 2011 Share Posted July 25, 2011 It appears you have an extreme amount of room treatments. I'm thinking your room must be pretty damped (dead). Quote Link to comment Share on other sites More sharing options...
Cornman Posted July 25, 2011 Share Posted July 25, 2011 "A rebuild BAT VK60 is driving the top.", oh yea,,now we are singing [8] [8], but as all know I am a bit biased,, [:$]. Would love to hear your system. Quote Link to comment Share on other sites More sharing options...
kwingylee Posted July 30, 2011 Author Share Posted July 30, 2011 Mark: My room is extremely small - as attested by those on this forum who managed to squeeze in there. The treatments are needed for my Harbeth M4os. The also sound good with the setup in the picture. The back wall is lined with atsacoustics 4" thick sound absorbing panels. I also have same panels on the side walls at the first reflection points. The panels are very reasonably price and are well worth the $$ I spent. Without them, my system is almost unlistenable. Quote Link to comment Share on other sites More sharing options...
kwingylee Posted July 30, 2011 Author Share Posted July 30, 2011 The VK-60 is a steal in the use market. I picked mine up from a buddy who knows Victor Khmenko personally, he sent it back to BAT to have it recalibrated, upgraded and voice for Harbeth M40s.Its an incredible sounding amp. Quote Link to comment Share on other sites More sharing options...
Taz Posted July 30, 2011 Share Posted July 30, 2011 It appears you have an extreme amount of room treatments. I'm thinking your room must be pretty damped (dead). Looks like a Candidate for my "Martha Stewart Collection" of room treatment, as someone called it. It wouldn't take any more room. Quote Link to comment Share on other sites More sharing options...
PrestonTom Posted July 30, 2011 Share Posted July 30, 2011 The original post indicated that you were crossing form the bass bin (jubilee copy) at 920Hz with a shallow filter. If this what you are doing, then your crossover point is close to an octave too high. -Tom Quote Link to comment Share on other sites More sharing options...
DrWho Posted July 30, 2011 Share Posted July 30, 2011 Btw, I agree about the SSSSSSHHH on the TAD driver - by far the hardest driver I've ever tried to voice. I think the TAD 4002's have a similar sound to them too, but not quite as dramatic. Are you doing any delay on the HF horn to time-align it with the bassbin? With such a shallow slope, I'd be curious how good the xover summation is between drivers. Quote Link to comment Share on other sites More sharing options...
kwingylee Posted July 30, 2011 Author Share Posted July 30, 2011 Dr. Who: I left the delay exactly the way you set them with the TAD/ALtec Combo. Its probably wrong but the results are so good that I am not messing with them. kwing Quote Link to comment Share on other sites More sharing options...
kwingylee Posted July 31, 2011 Author Share Posted July 31, 2011 Probably, but the results speak for themselves. I am not in themood to change anything just due to theorectical benefits, What do you suggess should be the ideal crossover ffequency? Quote Link to comment Share on other sites More sharing options...
Rudy81 Posted July 31, 2011 Share Posted July 31, 2011 Glad I stumbled on your post. Those JMLC horns look very nice. I have a pair of DIY Tractrix horns and love the depth, imaging and 'space' they create in my room. I am going to have to look for a set of those to try out. I'm sure my DIY project does not measure up to a professionally made set. Enjoy. Quote Link to comment Share on other sites More sharing options...
PrestonTom Posted July 31, 2011 Share Posted July 31, 2011 Probably, but the results speak for themselves. I am not in themood to change anything just due to theorectical benefits, What do you suggess should be the ideal crossover ffequency? I assume you addressing this toward me. I will also ignore the tone of your comments about "theoretical benefits". One can argue back and forth about the ideal crossover point. The elements to be considered are 1) a spectral region where the amplitude and phase of the two drivers are well-behaved and not changing rapidly. Ultimately this is required so the transition region (where the spectra overlap) has a predictable and even freq respsonse. BTW, this is why Dr Who asked about time alignment since this would produce a rpaidly change in phase and you could get peaks and dips on the crossover region. Other criteria, and these are frequently ignored, misunderstood or simply under-valued, are the consideration of whether the two drivers are still in their linear region (eg, a HF driver being forced to more air then it was designed for and the consequent distortion). The other is whether the dispersion of the two drivers is comparable at the candidate crossover point. This later criterion is strongly weighted by designers in pro-sound. There is a nice JAES paper by some of the JBL engineers (DB Keele was one of the authors) when one of the better JBL monitors was designed and released. If this criteria (comparable dispersion at the crossover point) is valued, then you will have a smoother crossover transition (among other things). This is why I suggested that you were about an octave too high. It is also a criteria that is highly weighted by the at least some of the enginering staff at Klipsch. BTW, problems with all these issues (mis-behaving amplitued and phase spectra, over-driving HF driver, and dispersion, can be minimized to an extent by using a steeper crossover filter. A 6 dB roll off may not mask these problems. But that is only part of a larger argument and certainly there is room for different trade-offs when using these ctriterial to choose a crossover point. Good lluck, -Tom Quote Link to comment Share on other sites More sharing options...
Rudy81 Posted July 31, 2011 Share Posted July 31, 2011 Since you are using a shallow crossover slope, have you encountered any problems at or near the crossover region due to time delay and phase with the folded horn? I am currently using a 24dB/oct slope and crossing near 800Hz. Granted, I am using a DBB ported bass bin, but was wondering if you have run into any of those issues. Quote Link to comment Share on other sites More sharing options...
PrestonTom Posted July 31, 2011 Share Posted July 31, 2011 Rudy, Have you measured or do you have a guess on what the difference in propogation delay is between the DBB bass bin and you HF section is? My guess, and it is only a guess, is that it is much smaller than what the OP has with his Jub-clone bass bin. Quote Link to comment Share on other sites More sharing options...
Marvel Posted July 31, 2011 Share Posted July 31, 2011 Then someone from the Chicago horn club loan a set of JMLC350 LeCleac'h horns... Cool! Do you know how much a pair would cost? Where was this pair made? I have some papers that JML wrote, and they look to be very good horns.Bruce Quote Link to comment Share on other sites More sharing options...
Rudy81 Posted July 31, 2011 Share Posted July 31, 2011 I don't have the exact time delay numbers I measured, but IIRC they were near 0.2 ms. Pretty much non-existent. The drivers are practically lined up vertically, so it is negligible. I know the delay with a folded horn needs to be taken into considerations due to the big time difference, which is why was curious what the OP had experienced. I have had various two way setups that used either Khorns or a La Scala bass bin. I used my Ashly crossover to compensate for the difference. Quote Link to comment Share on other sites More sharing options...
DrWho Posted August 1, 2011 Share Posted August 1, 2011 0.2ms is 1/4 wavelength at ~1kHz, which certainly isn't negligble. I would prefer to be in the 1/10 wavelength at a bare minimum... Quote Link to comment Share on other sites More sharing options...
Rudy81 Posted August 1, 2011 Share Posted August 1, 2011 0.2ms is 1/4 wavelength at ~1kHz, which certainly isn't negligble. I would prefer to be in the 1/10 wavelength at a bare minimum... Negligible relative to the delay difference when using a Khorn or La Scala bass bin. I currently have them aligned with the Ashly crossover. Quote Link to comment Share on other sites More sharing options...
kwingylee Posted August 1, 2011 Author Share Posted August 1, 2011 Marvel: They are $400 per pair,4 standard colors: green, black, blue or white. Custome colors are 10% higher I think. You can get them in 1", 1.5" or 2" throats. They are made in Poland by a company called autotech. I ordered mine through a group buy and AVSforum.com. I can find the link if you are interested. I can take a risk for $400. The wood horns are too expensive to buy .... sound unheard. Kwing Quote Link to comment Share on other sites More sharing options...
kwingylee Posted August 3, 2011 Author Share Posted August 3, 2011 Tom: I didn't mean to sound rude, but am merely attempting to reflect the journey I travelled with these speakers: having started from the theorectical ideal to admittedly non-ideal first order crossover. I started at around 700Hz with second order filters and am frankly surprise at where I ended up. Sometimes, the theorectical ideal simply does not sound as good as my current settings. Thanks for the comments.I am sure there will be changes in the future. I expect Dr. Who will come over and straighten me out LOL! Kwing Quote Link to comment Share on other sites More sharing options...
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