I may be being paranoid but I can notice on some tracks that my left driver is distorting at certain frequencies.
Fostex (FE168EZ) bought about 3 years ago. Has had lots of use but never abused. How long is the life expectancy for these?
It may be an amp issue. I have just finished a gainclone (stereo LM3875). I have swapped over the speaker cables at the amp end and it seemed that the right driver was not showing the same symptoms.
The sound is a grainy slightly fuzzy sound, just audible in some music (like cleanly recorded sax or clarinet). I thought it was just the sound of the reed at first but with my head really close I can defo hear something odd going on...
Any thoughts? Could it be DC on the left amp channel?
Fostex (FE168EZ) bought about 3 years ago. Has had lots of use but never abused. How long is the life expectancy for these?
It may be an amp issue. I have just finished a gainclone (stereo LM3875). I have swapped over the speaker cables at the amp end and it seemed that the right driver was not showing the same symptoms.
The sound is a grainy slightly fuzzy sound, just audible in some music (like cleanly recorded sax or clarinet). I thought it was just the sound of the reed at first but with my head really close I can defo hear something odd going on...
Any thoughts? Could it be DC on the left amp channel?
Try another speaker to see if it's the amp. If it is the Fostex, try removing and turning it over. It may be a rubbing coil and this may fix it.
I would at least take a precautionary look for DC. I'd also check to see if some damping material has come in contact with the cone.
dave
dave
Thanks guys. I'll have it out tomorrow and look for any of the above signs.
I measure DC at the speaker posts right, or will it need to be at some other part of the amp output?
I measure DC at the speaker posts right, or will it need to be at some other part of the amp output?
Erm
Be gentle on me...but I seem to be getting some odd readings so I am obviously not understanding this right.
I have set up my DMM with crock clips on the outputs of L speaker posts and have music running through it. I wanted to measure at 0 and full volume but the readings are fluctuating with the music.
Do I need to find a sine wave and use that? Maybe my DMM isn't set to the correct reading. (I can't find the instructions and I last read it about 3 years ago!)
Can someone be nice and treat me like a school kid and tell me what I need to do and which symbol to put the meter on.
eerm, please🙂
Be gentle on me...but I seem to be getting some odd readings so I am obviously not understanding this right.
I have set up my DMM with crock clips on the outputs of L speaker posts and have music running through it. I wanted to measure at 0 and full volume but the readings are fluctuating with the music.
Do I need to find a sine wave and use that? Maybe my DMM isn't set to the correct reading. (I can't find the instructions and I last read it about 3 years ago!)
Can someone be nice and treat me like a school kid and tell me what I need to do and which symbol to put the meter on.
eerm, please🙂
OK.
I put the black probe (in COM on meter) onto the ground post and the red on the positive. The symbol on the meter is the V with a line and a dotted line (not the wavy one) and the measurements were
L channel: -02.4mV at zero and -46.2mV at full volume
R channel: 11.1mV at zero and -36.0mV at full
Does that make any sense to anyone or am I just slipping into a coma?
I put the black probe (in COM on meter) onto the ground post and the red on the positive. The symbol on the meter is the V with a line and a dotted line (not the wavy one) and the measurements were
L channel: -02.4mV at zero and -46.2mV at full volume
R channel: 11.1mV at zero and -36.0mV at full
Does that make any sense to anyone or am I just slipping into a coma?
Well, I think it was a mounting issue. Took out the driver to inspect. Nothing unusual to be seen but when I tried again having put it back in the original problem seems to have gone. Screws were all tight, so I don't have a clue!
Fingers crossed it was just a blip and will never come back.
Fingers crossed it was just a blip and will never come back.
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probobly the early mentioned rubbing voice coil and by moving the driver you reset it to the correct position. I had a driver do this seemingly randomly and unfortunatly it was unfixable, although it was 15 years old.
OK - now i an worried.
The noise has returned. I only really notice it when playing at higher volume and certain frequencies tend to accentuate it. I was listening to some Arve Henriksen on trumpet and I can clearly hear someone eating crisps in the background on just the left driver.
It is not a problem with DC, as that is tested, and I have removed the driver and moved cables and checked for internal damping material touching etc.
I have never had a driver go so don't know what it sounds like. Can someone help?
Is there a 5 year replacement warrantee by any chance?
The noise has returned. I only really notice it when playing at higher volume and certain frequencies tend to accentuate it. I was listening to some Arve Henriksen on trumpet and I can clearly hear someone eating crisps in the background on just the left driver.
It is not a problem with DC, as that is tested, and I have removed the driver and moved cables and checked for internal damping material touching etc.
I have never had a driver go so don't know what it sounds like. Can someone help?
Is there a 5 year replacement warrantee by any chance?
Hi Martin,
1. Obvious question but you definitely swapped left and right at your source, already, to see if the noise stays in that particular driver, to rule out a source / pre / amp / loose connection problem?
2. So you already ruled out voice coil rubbing by pushing the cone down with your hand and listening for any mechanical noise?
3. Are you using vinyl? I'm wondering if something could be bottoming out on very low frequencies (from your description of "eating crisps" that would be unlikely but...)
4. Does it only happen after the speakers have warmed up a bit?
1. Obvious question but you definitely swapped left and right at your source, already, to see if the noise stays in that particular driver, to rule out a source / pre / amp / loose connection problem?
2. So you already ruled out voice coil rubbing by pushing the cone down with your hand and listening for any mechanical noise?
3. Are you using vinyl? I'm wondering if something could be bottoming out on very low frequencies (from your description of "eating crisps" that would be unlikely but...)
4. Does it only happen after the speakers have warmed up a bit?
Thanks for stating the obvious - it made go and re-check everything and this time things are a bit different.
I noticed it with both speakers but the left is slightly more obvious. I changed out the amp and replaced with my SET and the distortion is not there.
One thing to note is that the new amp is able to retrieve and punch out much more low sub frequency information.
One track I have (Arve Henriksen - Strjon) is a wall of sound (keyboard or computer generated sounds) which builds to a high volume and then Arve's trumpet leads over the top. There is a lot of continuous very low frequency in there.
So, it seems my issue is either electronics in the new amp or the drivers struggling to sound undistorted when being pushed to their limits with low frequencies. Remember that I am using single drivers so they are having to cover the entire range I can hear.
Can anyone explain what it sounds like when a single driver is topping out - hitting the physical boundaries of their low end frequency and how it might affect the mid/high frequencies.
On this particular track it sounds like hash, white noise or a very high frequency buzz (I would call a bee's buzz low frequency)
I noticed it with both speakers but the left is slightly more obvious. I changed out the amp and replaced with my SET and the distortion is not there.
One thing to note is that the new amp is able to retrieve and punch out much more low sub frequency information.
One track I have (Arve Henriksen - Strjon) is a wall of sound (keyboard or computer generated sounds) which builds to a high volume and then Arve's trumpet leads over the top. There is a lot of continuous very low frequency in there.
So, it seems my issue is either electronics in the new amp or the drivers struggling to sound undistorted when being pushed to their limits with low frequencies. Remember that I am using single drivers so they are having to cover the entire range I can hear.
Can anyone explain what it sounds like when a single driver is topping out - hitting the physical boundaries of their low end frequency and how it might affect the mid/high frequencies.
On this particular track it sounds like hash, white noise or a very high frequency buzz (I would call a bee's buzz low frequency)
OK I checked inside and there is no-one eating crisps in there.😉
Can anyone suggest anything it might be or what to test for?
Can anyone suggest anything it might be or what to test for?
Hi Martin,
Hmm, well, the good news is that it's not proven to be the drivers at the moment.
So regarding the four questions above, is this correct?
1. Yes, you switched left and right at the source, and no, the problem did not just stick in one speaker. So no, it's not a simple case of one blown speaker. And actually the problem is in both, though stronger in one than the other.
2. You gently pressed down on the cone (with no music playing) and definitely did not hear a mechanical scraping. (That's good!)
3. You're not using vinyl so it's not rumble (and is not that range anyway). However, your song in question does have a long continuous LF tone which heats up your voicecoil(s). Then after that, you get the low sound of a buzzing bee (is it 50-60hz low?) And when you switch to a different amp, the amount of bass goes down and the problem disappears, but that's probably just the reduced bass (?)
4. Yes, it does happen only after that continuous tone heats up your voice coils with the first amp.
Hmm. Some random ideas, since others have not yet chimed in:
5. If you very quickly switch left and right at your source, does the problem seem to follow? This is a fast version of #1 but trying to catch the voice coils while they are warm.
6. When the voice coils cool down fully, is the problem gone?
7. Do you have a third amp to try? For that matter, can you cobble together a different system (source / amp / wires) to see if the problem is still there?
8. Can you pinpoint the approximate frequency with a test-tone CD? If it's white/pink noise, that might be hard/impossible of course. Just want to rule out some weird resonance at a particular frequency, whether electrical or mechanical.
Hope that helps. I wouldn't have typed that if others had chimed in, because I'm not much of an expert, but as a fellow FE168E-Sigma owner, I feel your pain. 🙁
Hmm, well, the good news is that it's not proven to be the drivers at the moment.
So regarding the four questions above, is this correct?
1. Yes, you switched left and right at the source, and no, the problem did not just stick in one speaker. So no, it's not a simple case of one blown speaker. And actually the problem is in both, though stronger in one than the other.
2. You gently pressed down on the cone (with no music playing) and definitely did not hear a mechanical scraping. (That's good!)
3. You're not using vinyl so it's not rumble (and is not that range anyway). However, your song in question does have a long continuous LF tone which heats up your voicecoil(s). Then after that, you get the low sound of a buzzing bee (is it 50-60hz low?) And when you switch to a different amp, the amount of bass goes down and the problem disappears, but that's probably just the reduced bass (?)
4. Yes, it does happen only after that continuous tone heats up your voice coils with the first amp.
Hmm. Some random ideas, since others have not yet chimed in:
5. If you very quickly switch left and right at your source, does the problem seem to follow? This is a fast version of #1 but trying to catch the voice coils while they are warm.
6. When the voice coils cool down fully, is the problem gone?
7. Do you have a third amp to try? For that matter, can you cobble together a different system (source / amp / wires) to see if the problem is still there?
8. Can you pinpoint the approximate frequency with a test-tone CD? If it's white/pink noise, that might be hard/impossible of course. Just want to rule out some weird resonance at a particular frequency, whether electrical or mechanical.
Hope that helps. I wouldn't have typed that if others had chimed in, because I'm not much of an expert, but as a fellow FE168E-Sigma owner, I feel your pain. 🙁
The sound of a driver bottoming out is very obvious. It sounds like a fart (search for subwoofer vids on youtube - usually, the microphone is bottoming out, or the speaker itself is).
Good example of something hitting the stops here
http://www.youtube.com/watch?v=lugHQCNe458
From what you've described, it's not this.
Did you try rotating the drivers?
Apart from that, perhaps something is loose on the driver itself (check the wires that go to the voice-coil, and check the dustcap)?
Good example of something hitting the stops here
http://www.youtube.com/watch?v=lugHQCNe458
From what you've described, it's not this.
Did you try rotating the drivers?
Apart from that, perhaps something is loose on the driver itself (check the wires that go to the voice-coil, and check the dustcap)?
Thanks RJ for commenting on this. I will answer in red
So regarding the four questions above, is this correct?
1. Yes, you switched left and right at the source, and no, the problem did not just stick in one speaker. So no, it's not a simple case of one blown speaker. And actually the problem is in both, though stronger in one than the other.
Spot on. Exactly as described.
2. You gently pressed down on the cone (with no music playing) and definitely did not hear a mechanical scraping. (That's good!)
No noise.
3. You're not using vinyl so it's not rumble (and is not that range anyway). However, your song in question does have a long continuous LF tone which heats up your voicecoil(s). Then after that, you get the low sound of a buzzing bee (is it 50-60hz low?) And when you switch to a different amp, the amount of bass goes down and the problem disappears, but that's probably just the reduced bass (?)
This problem is not source related. It is present both when using my CDP as well as streaming audio through a Squeezebox - although the SB does create a worsened response than the CDP presumably because it is a cleaner more focused sound. The buzzing is high frequency, similar to the sound of a raspy reed in a clarinet not low like a bee. In fact, this afternoon I was listening while working and a large fly was fizzing away trying to get out of the window and the sound of its wings on the glass made me think it was happening in a different track!
4. Yes, it does happen only after that continuous tone heats up your voice coils with the first amp.
It seems more noticeable when I have been playing at higher volume for a long session and less so when just begun listening. It is possible to make it happen and hear the distortion if I play an offending track immediately from cold.
Hmm. Some random ideas, since others have not yet chimed in:
5. If you very quickly switch left and right at your source, does the problem seem to follow? This is a fast version of #1 but trying to catch the voice coils while they are warm.
This is tricky as I use bare wire clamped on to solid silver washers (not a fan of bananas). It takes a little while to unscrew the Cardas binding posts and swap the cables over at the amp end.
6. When the voice coils cool down fully, is the problem gone?
See above
7. Do you have a third amp to try? For that matter, can you cobble together a different system (source / amp / wires) to see if the problem is still there?
No third amp but I am going to a listening session with a fellow audiophile at the weekend so I'll take along the amp and see if I can get his speakers to react in the same way. It wasn't present when using my SET even a high volumes.
8. Can you pinpoint the approximate frequency with a test-tone CD? If it's white/pink noise, that might be hard/impossible of course. Just want to rule out some weird resonance at a particular frequency, whether electrical or mechanical.
I'll run a test tone CD and see if one frequency upsets them
Hope that helps. I wouldn't have typed that if others had chimed in, because I'm not much of an expert, but as a fellow FE168E-Sigma owner, I feel your pain. 🙁[/QUOTE]
They are amazing drivers when fed with a good signal, so I am reluctant to change them (plus they needed forever to loosen up and sound good)
I wonder if it could be some component in the amp?
So regarding the four questions above, is this correct?
1. Yes, you switched left and right at the source, and no, the problem did not just stick in one speaker. So no, it's not a simple case of one blown speaker. And actually the problem is in both, though stronger in one than the other.
Spot on. Exactly as described.
2. You gently pressed down on the cone (with no music playing) and definitely did not hear a mechanical scraping. (That's good!)
No noise.
3. You're not using vinyl so it's not rumble (and is not that range anyway). However, your song in question does have a long continuous LF tone which heats up your voicecoil(s). Then after that, you get the low sound of a buzzing bee (is it 50-60hz low?) And when you switch to a different amp, the amount of bass goes down and the problem disappears, but that's probably just the reduced bass (?)
This problem is not source related. It is present both when using my CDP as well as streaming audio through a Squeezebox - although the SB does create a worsened response than the CDP presumably because it is a cleaner more focused sound. The buzzing is high frequency, similar to the sound of a raspy reed in a clarinet not low like a bee. In fact, this afternoon I was listening while working and a large fly was fizzing away trying to get out of the window and the sound of its wings on the glass made me think it was happening in a different track!
4. Yes, it does happen only after that continuous tone heats up your voice coils with the first amp.
It seems more noticeable when I have been playing at higher volume for a long session and less so when just begun listening. It is possible to make it happen and hear the distortion if I play an offending track immediately from cold.
Hmm. Some random ideas, since others have not yet chimed in:
5. If you very quickly switch left and right at your source, does the problem seem to follow? This is a fast version of #1 but trying to catch the voice coils while they are warm.
This is tricky as I use bare wire clamped on to solid silver washers (not a fan of bananas). It takes a little while to unscrew the Cardas binding posts and swap the cables over at the amp end.
6. When the voice coils cool down fully, is the problem gone?
See above
7. Do you have a third amp to try? For that matter, can you cobble together a different system (source / amp / wires) to see if the problem is still there?
No third amp but I am going to a listening session with a fellow audiophile at the weekend so I'll take along the amp and see if I can get his speakers to react in the same way. It wasn't present when using my SET even a high volumes.
8. Can you pinpoint the approximate frequency with a test-tone CD? If it's white/pink noise, that might be hard/impossible of course. Just want to rule out some weird resonance at a particular frequency, whether electrical or mechanical.
I'll run a test tone CD and see if one frequency upsets them
Hope that helps. I wouldn't have typed that if others had chimed in, because I'm not much of an expert, but as a fellow FE168E-Sigma owner, I feel your pain. 🙁[/QUOTE]
They are amazing drivers when fed with a good signal, so I am reluctant to change them (plus they needed forever to loosen up and sound good)
I wonder if it could be some component in the amp?
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