Hi all,
Happy holidays to everyone!!
I'm not sure if this is the right place to post this, but I thought there might be some knowledgeable people out there who could provide a kind of "2nd Opinion" for me.
Here's the background...
I have a 12-13 year old (bought it new) Klipsch KSW150 subwoofer (10" @ 150W) connected to the LFE output of a Sony STR-DE835 receiver (5.1 @ 100W/ch). About 6-9 months ago I noticed a noise coming from the sub. It wasn't a "scritchy" sound which might indicate voice coil problems and it wasn't a buzzy or fuzzy noise typical of a torn cone or separated edging. It was more of a "clackety" sound, which I thought might be distortion issues. I noticed at that time the noise was obvious only during surround sound (movie, DVR, etc.) and not while a 2 ch. source (CD, tuner) was selected. Also, the sub had to be set at 25% level (volume) or higher for the noise to be heard. As a result, I assumed the receiver's decode circuitry might be the problem.
Just in case, I did do some cursory checking of the sub: pressed the cone a bit to listen for any voice coil rubbing (heard nothing), scanned the speaker for any obvious tears or material separation (nothing obvious). I focused mainly on the receiver. I scoped the output of the LFE at the input of the sub using surround sound, 2-channel and a low freq tone source. I saw no clipping issues and the signal did not appear distorted (at least as much as one can tell on a scope). I concluded I wasn't sure what was causing the noise and decided I would keep the sub level down below 25%.
Fast forward to a couple of weeks ago...I decided I was tired of missing the rich, low end (and rumble) when I could turn up the level of the sub. I flipped the sub over and examined it more closely this time. The "press" test made no noise. In fact, when I reached 1/4"-plus depression on the speaker cone, I felt I might actually poke finger holes in the cone. It felt fairly firm and strong. Visually, other than a bit of dust, there were no tears or separations in the cone or rubberized edging and the speaker looked as if it was brand new.
I also redid my listening test and discovered the problem does exist during 2-ch source material, as well. It turns out the sub needed to be at 50% level or higher to hear the same "clacketing" sound as could be heard on surround sound material at lower levels. While the receiver may not be completely in the clear, it seems the sub may truly be the source of the problem. I plan to check (scope, voltage, etc.) the sub amp and power supply (be nice if I could find a schematic so I knew what normal readings should be
and see (actually hoping to find) if there is a clipping issue (bad filter cap, resistor value change, etc.) in the amp circuitry.
This is where I could use some 2nd opinion feedback.....
I decided to reach out to some Klipsch experts so I posted about this problem on the Klipsch forum. I received feedback from an individual who seems to be fairly knowledgeable about this. What I was told is that this problem could be related to age. The material used for the speaker suspension may have weakened over time (something about the fiber structure?) and this could be allowing the speaker to "bottom out". Logically, it would make sense. However, I would think in a good, quality speaker, there would be margin in the design to allow for aging and prevent this kind of thing from happening. Then again, maybe because it is a good, quality speaker, there can be no room for margin.
Anyway, has anyone else experienced this? Is it a fairly common problem? I have Klipsch KG 2.5s for my front speakers. They're about 1-2 years older than the sub and show no signs of any kinds of problems. Then again, I may be trying to compare apples with oranges.
I am interested and appreciate any insight, comments, suggestions in sorting this out.
Thanks in advance and cheers....Steph
Happy holidays to everyone!!
I'm not sure if this is the right place to post this, but I thought there might be some knowledgeable people out there who could provide a kind of "2nd Opinion" for me.
Here's the background...
I have a 12-13 year old (bought it new) Klipsch KSW150 subwoofer (10" @ 150W) connected to the LFE output of a Sony STR-DE835 receiver (5.1 @ 100W/ch). About 6-9 months ago I noticed a noise coming from the sub. It wasn't a "scritchy" sound which might indicate voice coil problems and it wasn't a buzzy or fuzzy noise typical of a torn cone or separated edging. It was more of a "clackety" sound, which I thought might be distortion issues. I noticed at that time the noise was obvious only during surround sound (movie, DVR, etc.) and not while a 2 ch. source (CD, tuner) was selected. Also, the sub had to be set at 25% level (volume) or higher for the noise to be heard. As a result, I assumed the receiver's decode circuitry might be the problem.
Just in case, I did do some cursory checking of the sub: pressed the cone a bit to listen for any voice coil rubbing (heard nothing), scanned the speaker for any obvious tears or material separation (nothing obvious). I focused mainly on the receiver. I scoped the output of the LFE at the input of the sub using surround sound, 2-channel and a low freq tone source. I saw no clipping issues and the signal did not appear distorted (at least as much as one can tell on a scope). I concluded I wasn't sure what was causing the noise and decided I would keep the sub level down below 25%.
Fast forward to a couple of weeks ago...I decided I was tired of missing the rich, low end (and rumble) when I could turn up the level of the sub. I flipped the sub over and examined it more closely this time. The "press" test made no noise. In fact, when I reached 1/4"-plus depression on the speaker cone, I felt I might actually poke finger holes in the cone. It felt fairly firm and strong. Visually, other than a bit of dust, there were no tears or separations in the cone or rubberized edging and the speaker looked as if it was brand new.
I also redid my listening test and discovered the problem does exist during 2-ch source material, as well. It turns out the sub needed to be at 50% level or higher to hear the same "clacketing" sound as could be heard on surround sound material at lower levels. While the receiver may not be completely in the clear, it seems the sub may truly be the source of the problem. I plan to check (scope, voltage, etc.) the sub amp and power supply (be nice if I could find a schematic so I knew what normal readings should be
and see (actually hoping to find) if there is a clipping issue (bad filter cap, resistor value change, etc.) in the amp circuitry.This is where I could use some 2nd opinion feedback.....
I decided to reach out to some Klipsch experts so I posted about this problem on the Klipsch forum. I received feedback from an individual who seems to be fairly knowledgeable about this. What I was told is that this problem could be related to age. The material used for the speaker suspension may have weakened over time (something about the fiber structure?) and this could be allowing the speaker to "bottom out". Logically, it would make sense. However, I would think in a good, quality speaker, there would be margin in the design to allow for aging and prevent this kind of thing from happening. Then again, maybe because it is a good, quality speaker, there can be no room for margin.
Anyway, has anyone else experienced this? Is it a fairly common problem? I have Klipsch KG 2.5s for my front speakers. They're about 1-2 years older than the sub and show no signs of any kinds of problems. Then again, I may be trying to compare apples with oranges.
I am interested and appreciate any insight, comments, suggestions in sorting this out.
Thanks in advance and cheers....Steph
I appreciate that and understand how it can happen (I would expect some fairly serious distortion if it got to that point). However, Klipsch speakers are supposed to be good quality and had been doing fine for a long time playing pretty full surround sound material, so I would have expected this to happen a long time before now.
Thanks for the suggestion. I have not yet pulled the speaker from the box to check for any physical issues and to look at the signal to the speaker, but I'll keep the tinsel leads in mind to check them closely.
I too would be willing to bet that the spider on this particular model has loosened up dramatically, and combined with playing ultra-low LFE effects from movies, might be encountering a hard physical limit rather quickly in an enclosure that is likely not tuned low enough. Klipsch is good, but if you've ever seen the actual speaker drivers that are used in entry-level systems, makes you wanna slap yourself; very thin spiders, stamped steel frames, cheap terminals (usually spade type connectors).
Thanks much for the input and feedback, everyone!
I pulled the driver out of the enclosure to get a better look at it (I'm still amazed at how "new" it appears!). I cannot see anything from the outside that would indicate a physical problem. Cone, spider, etc. all look firmly attached. If the spider has become disconnected from the former, it's not obvious to me. I did gently shake the speaker and heard nothing that I could say was a problem (Not that I'm sure I could hear anything like that anyways). I redid a "press test" and everything still feels firm. I did carefully push the cone in and found that something did bottom out, but that was 3/4"-1" excursion of the cone into the basket/vc area.
However, I may have discovered something of importance. I reinstalled the driver, left the sub upside down and ran some fairly heavy surround sound source material to listen if the sound was coming specifically from the speaker or if there might have been something loose in the cabinet generating the noise. It was the speaker. What I did notice was that during fairly full lo-freq passages, the speaker did just fine. The bass was firm and solid. However, when these low freqs weren't playing and slightly higher freqs were, that's when I noticed the noise (now I'm not so sure it was actually a "clacketing" sound...maybe more "crackling"). Also, absence of any source input, I heard what could be a considered a fairly constant low-level pink or white noise coming from the speaker. The level control had no effect on this noise.
This may be wishful thinking, but I'm now back to wondering if the problem is a leaky cap (bypass, maybe), noisy resistor or marginal transistor (hopefully not a custom IC in the amp circuit (schematic, please I can't remember if I mentioned it, but at one time I had a noise (can't remember if it was the same as this one) that seemed (as in I was never sure) to be related to a dirty level control. I turned the control (and the cross over control) a few times and it appeared to go away. Maybe just coincidence. Also, I've had to resolder a cold connection on one of the ps filter caps).
If I can't find a schematic, I may just bite the bullet and replace any and all caps that could be possible sources of this. I'll get into it with a scope first, of course
In the end, it may still turn out to be the speaker/driver. However, by comparison the amp should be fairly easy (and, hopefully, cheap) to fix.
I'll keep you posted on my progress. Thanks again.
Cheers....Steph
I pulled the driver out of the enclosure to get a better look at it (I'm still amazed at how "new" it appears!). I cannot see anything from the outside that would indicate a physical problem. Cone, spider, etc. all look firmly attached. If the spider has become disconnected from the former, it's not obvious to me. I did gently shake the speaker and heard nothing that I could say was a problem (Not that I'm sure I could hear anything like that anyways). I redid a "press test" and everything still feels firm. I did carefully push the cone in and found that something did bottom out, but that was 3/4"-1" excursion of the cone into the basket/vc area.
However, I may have discovered something of importance. I reinstalled the driver, left the sub upside down and ran some fairly heavy surround sound source material to listen if the sound was coming specifically from the speaker or if there might have been something loose in the cabinet generating the noise. It was the speaker. What I did notice was that during fairly full lo-freq passages, the speaker did just fine. The bass was firm and solid. However, when these low freqs weren't playing and slightly higher freqs were, that's when I noticed the noise (now I'm not so sure it was actually a "clacketing" sound...maybe more "crackling"). Also, absence of any source input, I heard what could be a considered a fairly constant low-level pink or white noise coming from the speaker. The level control had no effect on this noise.
This may be wishful thinking, but I'm now back to wondering if the problem is a leaky cap (bypass, maybe), noisy resistor or marginal transistor (hopefully not a custom IC
in the amp circuit (schematic, please I can't remember if I mentioned it, but at one time I had a noise (can't remember if it was the same as this one) that seemed (as in I was never sure) to be related to a dirty level control. I turned the control (and the cross over control) a few times and it appeared to go away. Maybe just coincidence. Also, I've had to resolder a cold connection on one of the ps filter caps).If I can't find a schematic, I may just bite the bullet and replace any and all caps that could be possible sources of this. I'll get into it with a scope first, of course
In the end, it may still turn out to be the speaker/driver. However, by comparison the amp should be fairly easy (and, hopefully, cheap) to fix.
I'll keep you posted on my progress. Thanks again.
Cheers....Steph
What you need to do is use a function generator (sine wave) and do a slow sweep from 20Hz on up. If you don't have a function generator there are free software versions for computers using your sound card from your computer. Not the best but useable for this kind of testing.
You can do that with the speaker in free air (speaker sitting upright on a bench or table out of the box). If you hear the noise, you can start to figure out the cause.
If it sounds good in free air then place it back into the box and run the same test.
If it still sounds good, then start looking at your source material or receiver noise.
Hope that helps
You can do that with the speaker in free air (speaker sitting upright on a bench or table out of the box). If you hear the noise, you can start to figure out the cause.
If it sounds good in free air then place it back into the box and run the same test.
If it still sounds good, then start looking at your source material or receiver noise.
Hope that helps
I appreciate your suggestions. Months ago I had used a tone generator (NCH, limited shareware version) and ran that thru both the receiver and directly into the sub. However, since I kept the freq below 100Hz I never heard/saw any issues either aurally or on the scope (However, I also never looked at anything beyond the signal at the input of the sub). This new info may explain why. If I could get a hold of a sub or receiver with LFE out for temp loan, that would help localize the problem source. However, neither is an apparent option at the moment. For now, I'm more convinced it's in the sub rather than in the receiver (opinion always subject to change and that's where I'll focus my troubleshooting for now. I'll test first as a complete system, driving the sub "LFE" input directly from the s/w sweep gen. Hopefully, I can then use the scope to look at signals (where I can best figure out they exist w/out a schematic), see if I can replicate the problem and hope I can determine where, if anywhere, the problem originates. Gut says it's an "iffy" component (i.e bad cap) since it's more of a sporadic problem. That just may make it a challenge in reproducing the problem consistently enough to be able to track it down. Can't really tell at the moment if it's tied to a specific freq, set of freqs/range or doesn't seem to be dependent on freq at all. Time to be technician Any thought on whether the auto-turnon circuit could be a source? It is tied to the input somewhere up front and, while it's not supposed to inject anything back into the audio circuitry, it wouldn't surprise me if a diode or cap was allowing it (again, a schematic would be of great help). I'll post back what I do (or do not) find. Thanks again and cheers...Steph
and that's where I'll focus my troubleshooting for now. I'll test first as a complete system, driving the sub "LFE" input directly from the s/w sweep gen. Hopefully, I can then use the scope to look at signals (where I can best figure out they exist w/out a schematic), see if I can replicate the problem and hope I can determine where, if anywhere, the problem originates. Gut says it's an "iffy" component (i.e bad cap) since it's more of a sporadic problem. That just may make it a challenge in reproducing the problem consistently enough to be able to track it down. Can't really tell at the moment if it's tied to a specific freq, set of freqs/range or doesn't seem to be dependent on freq at all. Time to be technician Any thought on whether the auto-turnon circuit could be a source? It is tied to the input somewhere up front and, while it's not supposed to inject anything back into the audio circuitry, it wouldn't surprise me if a diode or cap was allowing it (again, a schematic would be of great help). I'll post back what I do (or do not) find. Thanks again and cheers...Steph
OK, so I planned to do a thorough test, but ended up not doing it I had some time today and decided to pull the amp/ps and just do visuals of the boards ahead of testing/troubleshooting. With the amp out of the box, I ran some recorded surround sound material and the crackling/clacketing sound wasn't there, even at fairly loud volumes. So, either a part was intermittent, or there was an intermittent connection on the board.
I pulled out a magnifying glass and did a close-up visual. What I saw reminded me that I when I had a noise problem some time ago (I mentioned this is a previous post), I must have gone in and done some resoldering then, mostly on the ICs (primarily 4558 op amps). I poked around a little, counted ~10 small value caps. Thought briefly about just replacing all the caps (most likely noise sources) and decided since the problem noise had disappeared, maybe I can just resolder parts of the board I had not yet done. My visual exam didn't turn up any obviously bad connections, but there were a few that seemed like possible candidates. Pulled out the soldering iron and went at it.
Put the sub back together and the good news: problem gone, at least, for the moment. Bad news: not clear to me what I actually did to fix it so I'll have to keep using it to see if this is just another coincidence of the problem going away after I did some repair work or if I actually solved the problem (might end up replacing all the electrolytics anyway). I'm happy it's not the speaker. Didn't want to think about having to replace it.
I have seen this kind of problem numerous times, but I never want to believe in bad production quality, especially from a company like Klipsch. Obviously, I'm in denial It's more common than I care to admit. About 6 months ago, I finished with having to resolder quite a bit of my Sony receiver (mostly the main board where a lot of heat is generated). There were numerous places (some very obvious even without any magnifying glass) where the connections were cracked. In fact, I was surprised the unit wasn't going into protection mode. I had to go into the receiver 3-4 times to fix all the bad connections It's now working solid, but only time will tell if I got them all or if no more show up.
So, thanks again to everyone for their suggestions and patience as I sorted this out. May all your problems in 2012 be solved so easily Happy (and safe!!) New Year to all. Cheers....Steph
I had some time today and decided to pull the amp/ps and just do visuals of the boards ahead of testing/troubleshooting. With the amp out of the box, I ran some recorded surround sound material and the crackling/clacketing sound wasn't there, even at fairly loud volumes. So, either a part was intermittent, or there was an intermittent connection on the board. I pulled out a magnifying glass and did a close-up visual. What I saw reminded me that I when I had a noise problem some time ago (I mentioned this is a previous post), I must have gone in and done some resoldering then, mostly on the ICs (primarily 4558 op amps). I poked around a little, counted ~10 small value caps. Thought briefly about just replacing all the caps (most likely noise sources) and decided since the problem noise had disappeared, maybe I can just resolder parts of the board I had not yet done. My visual exam didn't turn up any obviously bad connections, but there were a few that seemed like possible candidates. Pulled out the soldering iron and went at it.
Put the sub back together and the good news: problem gone, at least, for the moment. Bad news: not clear to me what I actually did to fix it so I'll have to keep using it to see if this is just another coincidence of the problem going away after I did some repair work or if I actually solved the problem (might end up replacing all the electrolytics anyway). I'm happy it's not the speaker. Didn't want to think about having to replace it.
I have seen this kind of problem numerous times, but I never want to believe in bad production quality, especially from a company like Klipsch. Obviously, I'm in denial
It's more common than I care to admit. About 6 months ago, I finished with having to resolder quite a bit of my Sony receiver (mostly the main board where a lot of heat is generated). There were numerous places (some very obvious even without any magnifying glass) where the connections were cracked. In fact, I was surprised the unit wasn't going into protection mode. I had to go into the receiver 3-4 times to fix all the bad connections It's now working solid, but only time will tell if I got them all or if no more show up. So, thanks again to everyone for their suggestions and patience as I sorted this out. May all your problems in 2012 be solved so easily
Happy (and safe!!) New Year to all. Cheers....Steph I appreciate your suggestions. Months ago I had used a tone generator (NCH, limited shareware version) and ran that thru both the receiver and directly into the sub. However, since I kept the freq below 100Hz I never heard/saw any issues either aurally or on the scope (However, I also never looked at anything beyond the signal at the input of the sub). This new info may explain why. If I could get a hold of a sub or receiver with LFE out for temp loan, that would help localize the problem source. However, neither is an apparent option at the moment. For now, I'm more convinced it's in the sub rather than in the receiver (opinion always subject to change
I wanted to add a bit of insight about this specific problem I had.
It's getting up towards a week and the sub seems to be working just fine (great to have that low end filled in again. Kinda like having added a sub to the system for the 1st time
I realized something as an after-thought about this specific problem. The problem I seemed to be having appeared to happen during, or just after, a rich low-freq passage. If the problem truly was a cold solder connection or otherwise loose part, it's very possible the low-freq vibrations may have been causing the problem to show up. The sub amp has a plastic case separating it from the sub driver chamber so the vibrations could either come thru the case or might have been transmitted thru the cabinet, enough to shake the part loose (When I removed the driver for testing, I noticed that while the mounting screws weren't loose, they didn't feel firmly tight, either...which might have contributed to the vibration problem). From my experience, when noise shows up in a circuit it is typically coming from a component, is fairly consistent in nature...easily repeatable and typically (tho, not always) affected by temperature. In my case, it seemed the level had to be high enough to cause the vibrations which shook the amp board.
I know. It's always easier to see things like this in hindsight However, I thought this worth sharing to hopefully save someone else a bit of time in troubleshooting these kinds of problems.
Again, thanks to those who took the time to help.
BTW - A tech at Klipsch was kind enough to send me a pdf version of the service manual for the KSW-100, KSW-150 and KSW-200 Subwoofers. Includes theory of operation, setup instructions (for the amp), schematics and parts list. If anyone needs a copy, send me a note.
Hope everyone had a great holiday season and is looking forward to a wonderful 2012!!
Cheers...Steph
It's getting up towards a week and the sub seems to be working just fine (great to have that low end filled in again. Kinda like having added a sub to the system for the 1st time
I realized something as an after-thought about this specific problem. The problem I seemed to be having appeared to happen during, or just after, a rich low-freq passage. If the problem truly was a cold solder connection or otherwise loose part, it's very possible the low-freq vibrations may have been causing the problem to show up. The sub amp has a plastic case separating it from the sub driver chamber so the vibrations could either come thru the case or might have been transmitted thru the cabinet, enough to shake the part loose (When I removed the driver for testing, I noticed that while the mounting screws weren't loose, they didn't feel firmly tight, either...which might have contributed to the vibration problem). From my experience, when noise shows up in a circuit it is typically coming from a component, is fairly consistent in nature...easily repeatable and typically (tho, not always) affected by temperature. In my case, it seemed the level had to be high enough to cause the vibrations which shook the amp board.
I know. It's always easier to see things like this in hindsight
However, I thought this worth sharing to hopefully save someone else a bit of time in troubleshooting these kinds of problems.Again, thanks to those who took the time to help.
BTW - A tech at Klipsch was kind enough to send me a pdf version of the service manual for the KSW-100, KSW-150 and KSW-200 Subwoofers. Includes theory of operation, setup instructions (for the amp), schematics and parts list. If anyone needs a copy, send me a note.
Hope everyone had a great holiday season and is looking forward to a wonderful 2012!!
Cheers...Steph
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Just wanted to circle back around and say that it's now been over 2 months and the subwoofer continues to work as I remember. The "clacketing/crackling" sounds are gone, low end is firm and rich.
Looks like the problem is solved. Not sure the real source of the problem, other than loose connections (or possibly a part that was "revived" when I resoldered everything).
I'm definitely a happy camper!!!
Thanks again to all who offered their insight and expertise.
Cheers...Steph
Looks like the problem is solved. Not sure the real source of the problem, other than loose connections (or possibly a part that was "revived" when I resoldered everything).
I'm definitely a happy camper!!!
Thanks again to all who offered their insight and expertise.
Cheers...Steph
Klipsh is not what it used to be
The sub amplifier are not from them and you will find other brands whit the same amp inside.
I have a Mission M-Cube sub and the amp inside is the same one you will find in the klipsh RW10.
Indigo Bash power supply and amp both proudly made in China.
Crap quality capacitors and load of dry solder joints.
Ric
The sub amplifier are not from them and you will find other brands whit the same amp inside.
I have a Mission M-Cube sub and the amp inside is the same one you will find in the klipsh RW10.
Indigo Bash power supply and amp both proudly made in China.
Crap quality capacitors and load of dry solder joints.
Ric
KSW-200 Service Manual
Steph,
I am having similar issues with a KSW-200, and I am wondering if you still have a copy of the service manual mentioned on this thread.
If yes, would you mind sending me a copy?
Thanks in advance!
D
Steph,
I am having similar issues with a KSW-200, and I am wondering if you still have a copy of the service manual mentioned on this thread.
If yes, would you mind sending me a copy?
Thanks in advance!
D
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