ZAKO Posted August 19, 2005 Share Posted August 19, 2005 The K77 problem Even gets worse... When you consider the mass of the diaphram. They were inconsistent. Some were a gram heavier than others. causing high frequency roll off. Nothing to do with the type of magnet used. The flux across the gap was the same. I found the diaphram thickness was not consistent from batch to batch. That why I still state the K77 or EVt35 should be retired & a better tweeter should be installed. There are several out there. Why are we going over & over on this old problem, wringing our hands & loseing sleep. A couple of years ago a suggested to BEC a new diaphram/voicecoil should be made for the K77, maybe aluminum to reduce mass. The TAD tweeter 703 uses Be. The horn on the TAD is a diffraction style like the K77/T35. So it costs a thousand bucks. About the cost to run your truck for a couple of months these days. I dont know why the Klipsch Co keeps putting phenolic junk in that K77. The have the funds to tool up and improve that tweeter. After all they claim to be as big a company as JBL.. But JBL still tools up to make better drivers & tweeters. A case in point the new 045Be pure beryllium Tweeter. The diaphram is .0016 inch (0.04mm) thick.& weighing just 0.0035 oz. with a smooth response out to 50k hz It has a high magnetic flux density of 2 tesla. Klipsch Co can do this if they put some of there money back into research. Dont get me started on the K55 problem ...Why did they run back to Atlas for the K55X what was the Klipsch co thinking of? They can design design a better driver than that. But no put that Atlas in & we will work around it with a new EQ. Crossover as big as your front door. Quote Link to comment Share on other sites More sharing options...
sfogg Posted August 19, 2005 Share Posted August 19, 2005 What.... this isn't considered a good tweeter.... Shawn Quote Link to comment Share on other sites More sharing options...
colterphoto1 Posted August 19, 2005 Share Posted August 19, 2005 your point Dean? Quote Link to comment Share on other sites More sharing options...
Deang Posted August 19, 2005 Share Posted August 19, 2005 You were worried about the 4100Hz response of the PD-5 -- I gave you a plot showing how far out it goes on a K-400. Certainly beaming quite a bit at that frequency, but the tweeter starts to come in around 4500 or so, and by the time we hit 6000, the tweeter is well into doing its thing. Quote Link to comment Share on other sites More sharing options...
colterphoto1 Posted August 19, 2005 Share Posted August 19, 2005 From the plot you posted, it looks like the Atlas is far inferior to any K55. Is that what I am reading? Seems like the driver's response should extend smoothly well PAST the crossover point. Doens't the tweeter just start to come into play at 6000, or is well on it's way at a much lower frequency? At a 6 db/octave slope, the tweeter would still be at like -3db at 4000 or so. Is this making any sense? Is the Atlas PD5Vh an inferior driver? Michael Quote Link to comment Share on other sites More sharing options...
BEC Posted August 19, 2005 Share Posted August 19, 2005 ---------------- On 8/19/2005 10:10:23 AM Maron Horonzak wrote: The K77 problem Even gets worse... When you consider the mass of the diaphram. They were inconsistent. Some were a gram heavier than others. causing high frequency roll off. Nothing to do with the type of magnet used. The flux across the gap was the same. I found the diaphram thickness was not consistent from batch to batch. That why I still state the K77 or EVt35 should be retired & a better tweeter should be installed. There are several out there. Why are we going over & over on this old problem, wringing our hands & loseing sleep. A couple of years ago a suggested to BEC a new diaphram/voicecoil should be made for the K77, maybe aluminum to reduce mass. The TAD tweeter 703 uses Be. The horn on the TAD is a diffraction style like the K77/T35. So it costs a thousand bucks. About the cost to run your truck for a couple of months these days. I dont know why the Klipsch Co keeps putting phenolic junk in that K77. The have the funds to tool up and improve that tweeter. After all they claim to be as big a company as JBL.. But JBL still tools up to make better drivers & tweeters. A case in point the new 045Be pure beryllium Tweeter. The diaphram is .0016 inch (0.04mm) thick.& weighing just 0.0035 oz. with a smooth response out to 50k hz It has a high magnetic flux density of 2 tesla. Klipsch Co can do this if they put some of there money back into research. Dont get me started on the K55 problem ...Why did they run back to Atlas for the K55X what was the Klipsch co thinking of? They can design design a better driver than that. But no put that Atlas in & we will work around it with a new EQ. Crossover as big as your front door. ---------------- Maron, Have you tested any of the K-77 (EV T-35) diaphragms made in the last 20 or so years? The phenolic is now very uniform and the leads are copper-beryllium. Guess it is time to post this response graph I did of three types of diaphragm material in a K-76. Hard to fault the phenolic in this one when compared to titanium. Bob Quote Link to comment Share on other sites More sharing options...
ZAKO Posted August 19, 2005 Share Posted August 19, 2005 BEC....Now thats what I like to see!!!!!Thats a heck of alot better than 20 years ago. Hot damn. You got my ol whiskers a twitchen. Quote Link to comment Share on other sites More sharing options...
BS Button Posted August 19, 2005 Share Posted August 19, 2005 Bob, From the looks of that graph, the mid could start falling off at around 3000 and you'd still be OK, eh? BS Quote Link to comment Share on other sites More sharing options...
Deang Posted August 19, 2005 Share Posted August 19, 2005 Bob -- your T35 at one meter with my RTA and microphone. Quote Link to comment Share on other sites More sharing options...
colterphoto1 Posted August 19, 2005 Share Posted August 19, 2005 ---------------- On 8/19/2005 7:42:17 PM BS Button wrote: Bob, From the looks of that graph, the mid could start falling off at around 3000 and you'd still be OK, eh? BS ---------------- Todd, I might not know what I'm talking about, but that would hold true ONLY if the crossover was set to 3000. As it is, we have 6000 Hz crossover between mid and tweeter. Now what? Michael Quote Link to comment Share on other sites More sharing options...
ZAKO Posted August 19, 2005 Share Posted August 19, 2005 DeanG....could be mic differences. Quote Link to comment Share on other sites More sharing options...
mikebse2a3 Posted August 20, 2005 Share Posted August 20, 2005 Hey Dean What are the differences in your and Bob"s test setups besides equipment? I believe you would have to setup the K77 test the same as Bobs to actually compare his and your test. Also using different resolution measurement systems can be tricky comparing results.I also couldn't tell what the graduation lines of yours or Bob's test are but looks like both are +/- 5db? Looks like your K77 measurement includes the response of the K55 also and if thats the case that and any differences in setup like if your K77 has grille cloth in front of it and any crossover differences that were used between your and Bobs measurement setups could effect the readings also. I would be curious to see your measurement made with the K55 replaced by a resistor to eliminate its acoustical output while leaving the electrical crossover response undisturbed as much as possible. Then we would see the K77 response without any interferance from the K55 for comparison in your test. mike Quote Link to comment Share on other sites More sharing options...
BEC Posted August 20, 2005 Share Posted August 20, 2005 Mike, There are a couple of different topics going on here at once. I was posting a comparison of diaphragm materials for Maron to show that phenolic is not inferior when compared to titanium and poly in a K-76. I can't do that same test with a K-77 because I don't have the three types of diaphragms for a K-77. Bob Quote Link to comment Share on other sites More sharing options...
mikebse2a3 Posted August 20, 2005 Share Posted August 20, 2005 Thanks Bob I should have read a little closer. The phenolic does seem to hold its own. Did you do listening test also? If you did were you able to perceive any differences between the diaphrams? mike Quote Link to comment Share on other sites More sharing options...
colterphoto1 Posted August 20, 2005 Share Posted August 20, 2005 Guys, can we get back to the Atlas issue please? If it's rated and measured to around 4kHz and the crossover is set to 6kHz, isn't there a problem with using the Atlas as a replacement for K55? Michael Quote Link to comment Share on other sites More sharing options...
BEC Posted August 20, 2005 Share Posted August 20, 2005 Sorry Michael. Mike, I can't hear a difference between the phenolic and the titanium in a K-76. I can easily hear the difference between either of those and the poly diaphragm. Bob Michael, I think you are missing the point of the horn used for testing. The horn has a lot to do with the drivers frequency response. Bob Quote Link to comment Share on other sites More sharing options...
sfogg Posted August 20, 2005 Share Posted August 20, 2005 "If it's rated and measured to around 4kHz and the crossover is set to 6kHz, isn't there a problem with using the Atlas as a replacement for K55" The K55s don't get up to 6k all that well either. Look at the measurements I posted earlier of actual Klipsch badged drivers. Probably why Klipsch changed the crossover to 4500 on later units. Shawn Quote Link to comment Share on other sites More sharing options...
colterphoto1 Posted August 20, 2005 Share Posted August 20, 2005 OHHHHH, that changes everything. So when I upgrade/modify crossovers, the new mid/hi point should be 4500 Hz? Bob, Dean- does this sound like the right thing to do? Quote Link to comment Share on other sites More sharing options...
sfogg Posted August 20, 2005 Share Posted August 20, 2005 Not if the tweeters can't handle that crossover point. (Welcome to the world of speaker design/modification) There are other drivers that can get to 6k easily. This goes higher then the K77s I had in my system. So much so that I use it as a two way. Shawn Quote Link to comment Share on other sites More sharing options...
colterphoto1 Posted August 20, 2005 Share Posted August 20, 2005 So what are we to do, just live with it??/ Quote Link to comment Share on other sites More sharing options...
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