Deang Posted May 12, 2006 Share Posted May 12, 2006 Cornwall II response. Quote Link to comment Share on other sites More sharing options...
sfogg Posted May 12, 2006 Share Posted May 12, 2006 "But the frequencies at which those distortions occur is irrelevant of the power (mostly irrelevant anyway). The power/efficiency/watever else mostly just affects the magnitude...the magnitude of the same frequencies. I dunno how to say it more clearly." The frequency is only if you are limiting 'cone breakup' to the 'bell mode' resonance. That are basically other types of cone breakup. Others are not specific to a frequency and more related to power level. "In such a situation the cone-breakup on the hornloaded driver shifts lower in frequency." If you are talking about the bell mode it should drop in frequency... the air is sort of like mass damping the woofer which will lower a resonance frequency. At the same time though the air is acting to damp the woofer... the bell mode may decay faster too. "And talking about these systems in the large-signal world is a bit silly because the issues get swamped by other non-linear factors. (there's about 3 dozen of them...surely nobody wants to start discussing all of them)." We live in both a small and large signal world. If they get swamped by three dozen other non linearities then they are pretty much irrelevant to worry about in this context. "That's my take on it too actually...it's a pretty fundamental rule of speaker building actually - choose a passband for the system where cone-breakup isn't occuring." Yes, that is true but that isn't actually what I was saying. Other types of cone breakup (not bell mode) can generate basically noise that has no simple connection to the frequency the driver is reproducing. For example say you are feeding the driver 500hz and pushing the cone into flexing (not rining). That flexing sort of acts like a different radiator that is doing its own thing. It could be spitting out noise between 2kHz and 3kHz for example. In a case like that that type of breakup would be more audible on the Cornwall. The K'Horns bass bin is an acoustic low pass filter. That noise from the cone breakup will be attenuated greatly just by trying to pass through the bass horn. In the Cornwall there is no acoustic low pass filter that could attenuate that. Shawn Quote Link to comment Share on other sites More sharing options...
Q-Man Posted May 12, 2006 Share Posted May 12, 2006 Before, I just finished building the top and I was still experimenting with the network in that picture. Quote Link to comment Share on other sites More sharing options...
Rockets Posted May 13, 2006 Share Posted May 13, 2006 Q-man the 511b's may indeed be designed for 500 hz, but they will go to 400 hz, maybe even down to 350hz . Granted it's not 300hz, but for some of us the compromise is a necessary evil. BTW, I think I stole this plot from Shawn...hope you don't mind !!! Quote Link to comment Share on other sites More sharing options...
djk Posted May 13, 2006 Share Posted May 13, 2006 You have to allow for some overlap at the crossover point, even if using an extreme slope on the network. Quote Link to comment Share on other sites More sharing options...
formica Posted May 14, 2006 Share Posted May 14, 2006 ... Quote Link to comment Share on other sites More sharing options...
jorjen Posted May 14, 2006 Share Posted May 14, 2006 Just won an auction for a brand new, in the box pair of 2404H's for my CornScala project. Thought I would throw that out there. [H] Quote Link to comment Share on other sites More sharing options...
3dzapper Posted May 14, 2006 Share Posted May 14, 2006 Jordan, []!! Reading this thread is like watching a soap opera, plot, sub plot, another plot..... The doubling distortion of the K-33 in the Cornwall cabinette at 120+/- Hz is very obvious in that plot Dean. Thanks. Do you suppose the standing wave problem that Klipsch discovered while developing the Cornwall III is that dip centered around 50 Hz? Edit: I just ran into a website where any neophites can find definitions of the terms the experts are using here such as "cone break-up" and "bell modes": http://www.webervst.com/spterm.html Quote Link to comment Share on other sites More sharing options...
JJkizak Posted May 14, 2006 Share Posted May 14, 2006 That Corwall II response curve is mighty ratty for such a fine sounding speaker. JJK Quote Link to comment Share on other sites More sharing options...
Coytee Posted June 2, 2006 Author Share Posted June 2, 2006 I just spoke to John with JBL tech. support and he said that the 2404H and the 2404H-1 both use the same diaphragm. The diaphragm # is D16R-2405. His number (818) 895-8157. Was perusing this thread again and noticed this. Just yesterday I ordered replacement diaphragms for my 2404's. I was told there are 8 ohm versions and 16 ohm versions. The 8 ohm version (suggested by Al K) has a part number of "D8R075". The 8 means 8 ohms. I asked if the 16 ohm version was D16R and he said yes. I'm not sure if it matters, but I interpreted your part number above as the 16 ohm version as per yesterday's conversation and just wanted to bring the point up about the part number for the 8 ohm version. Quote Link to comment Share on other sites More sharing options...
Coytee Posted June 2, 2006 Author Share Posted June 2, 2006 Oh, and I ordered the 8 ohm versions from M&L Sound, here in Knoxville ( 865-693-5058) for $82.50 each plus shipping. [] Quote Link to comment Share on other sites More sharing options...
D-MAN Posted June 2, 2006 Share Posted June 2, 2006 Hopefully, you will only have to change the diaphragms once. The 2404H is a nasty little piece of work to take apart and put back together. Watch them teeny little wires, which were broke in one of mine! Dana Quote Link to comment Share on other sites More sharing options...
ZAKO Posted June 2, 2006 Share Posted June 2, 2006 The D8R075 diaphrams are thicker & do not go as high in frequency. They are used in the JBL 075 bullet tweeter & go out to about 15K Although it can be used in the 2404 . The diaphramin the 2404H will go out to 21.5K The true 2404H is 16 ohm. the true 8 ohm lighter diaphram version is no longer available. Quote Link to comment Share on other sites More sharing options...
Guest " " Posted June 2, 2006 Share Posted June 2, 2006 Hopefully, you will only have to change the diaphragms once. The 2404H is a nasty little piece of work to take apart and put back together. Watch them teeny little wires, which were broke in one of mine! Dana know what you mean...years back I used to be able to unwind the coils from both ends a half a turn, and after reversing the mounting polarity, was able to salvage many diaphrams using the teeny weeny wires. now i can barely see the teeny weeny wires. Quote Link to comment Share on other sites More sharing options...
Guest " " Posted June 2, 2006 Share Posted June 2, 2006 Hopefully, you will only have to change the diaphragms once. The 2404H is a nasty little piece of work to take apart and put back together. Watch them teeny little wires, which were broke in one of mine! Dana know what you mean...years back I used to be able to unwind the coils from both ends a half a turn, and after reversing the mounting polarity, was able to salvage many diaphrams using the teeny weeny wires. now i can barely see the teeny weeny wires. Quote Link to comment Share on other sites More sharing options...
Guest " " Posted June 2, 2006 Share Posted June 2, 2006 Hopefully, you will only have to change the diaphragms once. The 2404H is a nasty little piece of work to take apart and put back together. Watch them teeny little wires, which were broke in one of mine! Dana know what you mean...years back I used to be able to unwind the coils from both ends a half a turn, and after reversing the mounting polarity, was able to salvage many diaphrams using the teeny weeny wires. now i can barely see the teeny weeny wires. Quote Link to comment Share on other sites More sharing options...
Guest " " Posted June 2, 2006 Share Posted June 2, 2006 Hopefully, you will only have to change the diaphragms once. The 2404H is a nasty little piece of work to take apart and put back together. Watch them teeny little wires, which were broke in one of mine! Dana know what you mean...years back I used to be able to unwind the coils from both ends a half a turn, and after reversing the mounting polarity, was able to salvage many diaphrams using the teeny weeny wires. now i can barely see the teeny weeny wires. Quote Link to comment Share on other sites More sharing options...
formica Posted June 2, 2006 Share Posted June 2, 2006 know what you mean... dejavue? Quote Link to comment Share on other sites More sharing options...
Rockets Posted June 2, 2006 Share Posted June 2, 2006 No, this is Deja vu... http://www.metacafe.com/watch/50822/criss_angel_deja_vu/ forgive me for going off topic...this just came to mind after your comment! Quote Link to comment Share on other sites More sharing options...
DrWho Posted June 2, 2006 Share Posted June 2, 2006 know what you mean...years back I used to be able to unwind the coils from both ends a half a turn, and after reversing the mounting polarity, was able to salvage many diaphrams using the teeny weeny wires. now i can barely see the teeny weeny wires. ooo, that's clever....Imma have to try that on one of my old voice coils. Quote Link to comment Share on other sites More sharing options...
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