gheth54 Posted August 30, 2022 Share Posted August 30, 2022 Morning, I’ve been chasing a speaker problem in my system that I really could use some expert help. A few weeks ago I noticed the stereo staging collapsed and the center moved about 2 feet to the right of my optimal listening position. In 2 channel stereo mode the only speakers running are a pair of original 2001, Klipsch, RF-3s. A little investigation found the black ground wire of the left speaker’s upper 8 inch woofer came loose. The metal clip crumbled when I attempted squeezing it tighter, so I had to replace the spade clip. Now I find even when my RAT Shack meter shows the two speakers are equal, when I play music it still favors the right speaker. First move was to swap the left and right with the center channel, and substituting the interconnects, but no change. I don’t know how long the woofer was disconnected, could it have caused some kind of damage to the crossover or other drivers? Over the weekend I disassemble the pair and had a close look at the drivers and crossovers. All 4 woofers read around 6 ohms and both tweeters are around 3 ohms. But a red flag is the crossover of the speaker that had the ground wire come loose has a slight “cooked” smell of over heated electronics. That prompted me to dig deeper, removing and testing all of each board’s 3 caps, and testing the 3 coils and resistor while on the boards. None of the components looked obviously bad and all the caps and resistors tested well within their marked values. I do wonder about the health of the inductor coils. According to the schematic and testing: Schematic Value Right Left Woofers 0.75mH, 5%, DCR<0.3 ohms 0.59mH, 0.7ohms 0.59mH, 0.6 ohms Tweeters 0.25mH, 5%, DCR<0.50 ohm 0.24mH, 0.9 ohms 0.25mH, 1.0 ohms 0.30mH, 5%, DCR<0.55 ohm 0.19mH, 0.9 ohms 0.20mH, 0.9 ohms While the two 0.25mH coils look good, the tested values of the 0.75mH and 0.30mHs look way out of spec. Do these numbers show they are “cooked” and need replacing? Any other observations or help will be greatly appreciated! Thanks Quote Link to comment Share on other sites More sharing options...
Deang Posted August 30, 2022 Share Posted August 30, 2022 You measured everything in circuit, so I wouldn't expect the values to match the schematic. Since the values measure the same on left and right, I would say you're fine, and the shift in balance is being caused by your room. Quote Link to comment Share on other sites More sharing options...
gheth54 Posted August 30, 2022 Author Share Posted August 30, 2022 Thanks for the quick reply! I removed all 3 caps (18uF, 4.5uf, and 12uf) from the boards and tested them separately. Removing the caps also had the benefit of isolating the coils and resistor. So, while they were still on the board, there shouldn't have been any errors from the other components. Quote Link to comment Share on other sites More sharing options...
Deang Posted August 30, 2022 Share Posted August 30, 2022 The values in both speakers match, so I wouldn't worry about it. Maybe Klipsch made a silent change. Quote Link to comment Share on other sites More sharing options...
jjptkd Posted August 30, 2022 Share Posted August 30, 2022 1 hour ago, gheth54 said: A few weeks ago I noticed the stereo staging collapsed and the center moved about 2 feet to the right of my optimal listening position. In 2 channel stereo mode the only speakers running are a pair of original 2001, Klipsch, RF-3s. Now I find even when my RAT Shack meter shows the two speakers are equal, when I play music it still favors the right speaker. First move was to swap the left and right with the center channel, and substituting the interconnects, but no change. First thing I would do is swap left and right speakers leaving everything the same, this will isolate the problem to the speaker if it follows the speaker. I have seen RCA cables just stop working or create problems like you describe, I've also seen Receiver / amp channels suddenly develop similar problems. From the sounds of it from all your testing it would appear as though the speakers themselves are fine. 1 Quote Link to comment Share on other sites More sharing options...
gheth54 Posted August 30, 2022 Author Share Posted August 30, 2022 I figured the values being consistent between the two speakers might be a good indicator everything is OK. But then figuring in their age is over 20 years old, it wouldn't be surprising if they are ready for some refreshing. Thinking back I seem to remember one of the tweeters not sounding as loud as the other. Besides whether it actually making sound and its resistance, is there any other way of telling if one of the tweeters has a problem? Quote Link to comment Share on other sites More sharing options...
Deang Posted August 30, 2022 Share Posted August 30, 2022 The plastic horns are sonically welded. Make sure they are both still firmly attached. Quote Link to comment Share on other sites More sharing options...
billybob Posted August 30, 2022 Share Posted August 30, 2022 (edited) 8 minutes ago, gheth54 said: I figured the values being consistent between the two speakers might be a good indicator everything is OK. But then figuring in their age is over 20 years old, it wouldn't be surprising if they are ready for some refreshing. Thinking back I seem to remember one of the tweeters not sounding as loud as the other. Besides whether it actually making sound and its resistance, is there any other way of telling if one of the tweeters has a problem? Could use a paper roll to listen to each tweeter, and then swap entire speakers from left to right exact position, and listen to each again using the same source and music as the first time before speaker swap. Unless you are unable to manipulate the physical size and weight. Edited August 30, 2022 by billybob Quote Link to comment Share on other sites More sharing options...
billybob Posted August 30, 2022 Share Posted August 30, 2022 And, make certain that connection on rear of speaker cabinets is tight including strap that is removed for bi-amp. Just as a maintenance check. Quote Link to comment Share on other sites More sharing options...
gheth54 Posted August 30, 2022 Author Share Posted August 30, 2022 I just got off the phone with MidwestSpeaker asking about their aftermarket replacement titanium dome tweeter. Figured I'd check them out just in case I need a replacement. Anybody here have any experience with their aftermarket replacements? Also had a look at both tweeter's diaphragm and coils. While both look nice with no evidence of burning, the ferrofluid was chunky, looking like the caked oil you see on an old, neglected motor. Brian from Midwest told that happens over the years and replacement isn't a difficult job. So, I guess I'll order a couple of 1" tweeter ferrofluid packets. The other issue is any recommendation for a good adhesive for attaching the components back on the board? Usually I just use hot glue, but I've read on several DIY sites it looses its adhesion in around a month. I have a lot of experience with how destructive vibrations can be to electronics, so I want to get it right the first time! Billybob, the paper roll is a great idea, almost ashamed I didn't think of it myself. The speakers are bi-wired, so disconnecting the woofers wire should make it easier hearing if one is lower than the other. Would just running the tweeters by themselves possibly cause any problem in the tweeter circuit? I've already visited the "loose post" and had to tighten all 8 post's 8mm nut. 1 Quote Link to comment Share on other sites More sharing options...
Deang Posted August 30, 2022 Share Posted August 30, 2022 I've tried them all. Don't laugh - Goop Marine. Make sure the leads go back through the holes before you drop the cap. Don't press flush to the board, just tap it down a bit. Quote Link to comment Share on other sites More sharing options...
billybob Posted August 30, 2022 Share Posted August 30, 2022 (edited) 54 minutes ago, gheth54 said: I just got off the phone with MidwestSpeaker asking about their aftermarket replacement titanium dome tweeter. Figured I'd check them out just in case I need a replacement. Anybody here have any experience with their aftermarket replacements? Also had a look at both tweeter's diaphragm and coils. While both look nice with no evidence of burning, the ferrofluid was chunky, looking like the caked oil you see on an old, neglected motor. Brian from Midwest told that happens over the years and replacement isn't a difficult job. So, I guess I'll order a couple of 1" tweeter ferrofluid packets. The other issue is any recommendation for a good adhesive for attaching the components back on the board? Usually I just use hot glue, but I've read on several DIY sites it looses its adhesion in around a month. I have a lot of experience with how destructive vibrations can be to electronics, so I want to get it right the first time! Billybob, the paper roll is a great idea, almost ashamed I didn't think of it myself. The speakers are bi-wired, so disconnecting the woofers wire should make it easier hearing if one is lower than the other. Would just running the tweeters by themselves possibly cause any problem in the tweeter circuit? I've already visited the "loose post" and had to tighten all 8 post's 8mm nut. No, it would not hurt. @Crankysoldermeister ☕ Edited August 30, 2022 by billybob Quote Link to comment Share on other sites More sharing options...
gheth54 Posted September 1, 2022 Author Share Posted September 1, 2022 Yesterday I got some time to reassemble the crossovers and speakers. Crankysoldermeister; thanks for the tip on Goop, Marine. It was perfect for adhering the caps to the board. Just oozed some on a Q-tip and spread it over the contact area. Testing the system with a few CDs found nothing really changed, still favored the right speaker. So I used Billybob’s (Thanks Billybob) tip to listen to each driver through a paper tube. While the tweeters sounded about equal, I noticed the woofer that was still connected while its speaker mate was disconnected, sounded lower than all the other woofers. Early this morning I swapped it with its counterpart in the other speaker and I’m waiting for my neighbor to leave for work before I see what happens. As a mech. engineer I have a fairly basic electronics knowledge, so please feel free putting me right if my analysis is off. Both woofers are wired in parallel, the signal is seeing the inductance of both speakers equally. But with one woofer not in the circuit, the connected driver was seeing the full power (load?), rather than it being split between it and the other driver. Could that result in some kind damage, like over heating the connected driver and/or the crossover? 1 Quote Link to comment Share on other sites More sharing options...
Deang Posted September 1, 2022 Share Posted September 1, 2022 You would really have to be jacking on the volume. Those woofers are pretty robust. Quote Link to comment Share on other sites More sharing options...
billybob Posted September 1, 2022 Share Posted September 1, 2022 @gheth54 Quote Link to comment Share on other sites More sharing options...
Deang Posted September 1, 2022 Share Posted September 1, 2022 You need to measure the DCR and inductance of a known, working woofer - and then measure the suspected bad one. Quote Link to comment Share on other sites More sharing options...
gheth54 Posted September 8, 2022 Author Share Posted September 8, 2022 Sorry for not getting back right away, but an emergency popped up at work that required a bit of travel and my total attention. The silver lining is it earned more audio and cat food money! LOL Deang; how would I measure the DCR of a speaker? I have one of those electronic component testers (M8 Transistor Tester or Electronics Tester For Dummies), would that give an accurate value? A few of the audiophile EEs and Elec. Techs in my research unit told me after over 20 years they had no doubt the crossover's caps were in need of refreshing. Especially considering Klipsch probably sourced them from the lowest bidder. If I use the 1%, Dayton caps the total costs for both speakers, including 2 packets of ferrofluid, should be around $50. Cheap, compared to the usual expenses associated with this addiction! The stock Klipsch crossovers came with 5% caps, and I've read a post here claiming that Dayton 5%s actually test much better than they're rated. Any thoughts on this would be a great help. Thanks All Quote Link to comment Share on other sites More sharing options...
billybob Posted September 8, 2022 Share Posted September 8, 2022 @deang Quote Link to comment Share on other sites More sharing options...
gheth54 Posted September 8, 2022 Author Share Posted September 8, 2022 A quick question about how this forum works. Why are there 2 replies in this thread from billybob that I don't see any text? Quote Link to comment Share on other sites More sharing options...
billybob Posted September 8, 2022 Share Posted September 8, 2022 7 minutes ago, gheth54 said: A quick question about how this forum works. Why are there 2 replies in this thread from billybob that I don't see any text? Because the first one was tagging you. The second is tagging the one you are asking questions of. You can quote the member which does this for you automatically or the former. Another is, you are not following your own topic thread. Look at the bottom where it shows the follow. When a member is following, they will be notified of activity. I simply am notifying the parties by... @gheth54 Quote Link to comment Share on other sites More sharing options...
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