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reasons for subwoofer damage?

Wharfedale Diamond 11.1 & 11.2 Speakers

manu4panjab

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hey guys what are the reasons for subwoofer damage and how do we know if its damage and what is subwoofer bottoming out is it bad or not,what is subwoofer farting sound ,what is port noise
do playing at higher volumes continously damage it and for example if a subwoofer is capable of producing going down to just 30 hz and we feed 20 hz sinwave does it damage it

please guide :rolleyes:
 
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manu4panjab

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hello guys
i have a polk psw 125 subwoofer last day when i'm playing transformers 2 again i notice my subwoofer won't produce the same depth or you can say can't go that deep(according to its capacity) as it was use to i hear less bass on same scene i even try some hip hop songs which i use to know for bass but here too polk produce less bass than its use to
did i damage my subwoofer actually two days back when i first time playing transforemrs 2 i played it at super high volumes did i damage it by playing that hard
polk psw125 also produce some farting sound why is it is it damage or my avr onkyo 807 don't send signal properly should i reset onkyo 807
one more thing after some resting for subwoofer like one hour when i play it it seems the sub produce very great sound like it use to by after only 15 mintues its reduce bass it happens everytime after give subwoofer rest for an hour and again after 15 to 20 mintues its reduce its bass is there a problem with its amplifier does it heat up after 15 to 20 mintues of playing since last day
so what's the reason is it damage
please reply
 
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rikhav

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Maybe the sub amp is getting over heated? Also the farting sound is due to damaged cone or rubber surround
Just my thoughts, need to wait for experts to post as i don't have any experience with active subs and avr

After i posted you edited your post. We both have same views about the sub amp getting heated.
 

manu4panjab

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Maybe the sub amp is getting over heated? Also the farting sound is due to damaged cone or rubber surround
Just my thoughts, need to wait for experts to post as i don't have any experience with active subs and avr

After i posted you edited your post. We both have same views about the sub amp getting heated.

thanks for reply bro yaaa i'm waiting for our experts here to reply lets see what will they say about my problem
i'm thinking the same that after only 15 mintues subwoofer reduce its bass sound very very flat and farting sound is there too i guess i damage the subwoofer transformers 2 is a very bass heavy movie and i played at 0db(volume of onkyo 807 is from -80 db to +18db) insane volume for continously 2 and half hrs. until the movie finish
 

venkatcr

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Manu:

I have some thoughts on your system and your use of your system.

1. See if you can open the face plate covering the sub's driver and visually inspect the driver for any damage.

2. Since your sub seems to come back to life after some 15 minutes of rest, this could be a case of overheating and clipping. The strange sound that you hear could be an amplified noise of some static or interference noise flowing into the sub. It could also be the sound of the overstressed and overloaded capacitor inside that is trying to empty itself.

3. Subwoofers work on a slightly different principle as compared to other speakers. For one they have their own amplifiers. The AVR sends a 'pre-out' to the sub which it amplifies internally. Just like other amplifiers, if you overload the amplifier from the source, it could trip. If there is no tripping mechanism, it is possible that the amp drives itself to destruction. If you are going to use nearly 50% of your AVR's power, first go to the the speaker set-up and set up the relative sound level of your sub very low. Then use the sub's amplifier pot behind the sub to set your desired output level.

4. Set the relative sound level of all speakers including sub to a max of 75dB using a SPL meter. You should do this using the test tone available in the AVR.

5. When you are doing this for the sub, you have to adjust both the sound level set up in the AVR and the amplifier pot in the sub. As I said before keep the sound level of the sub in the AVR to a very low level.

6. Use a power conditioner that is at least 1.5 times the max load capacity of your sub. It is also possible that your sub is not able to draw the required current from the mains. See if you also ensure that the power to the AVR and the one to the sub are from different switch boards.

After doing all this, run the system through a movie and see what happens. If things work well, your sub is all right.

I have mentioned this before, but listening to movies at insane volumes WILL destroy your ear. You will certainly get what is called 'Tinnitus'. This is a symptom where you hear a high pitched sound all the time. Additionally, your ear drums could become loose and flabby leading to a permanent deafness. Under no circumstances should the sound level of your system cross 80dB at the most. It is safer to keep it between 70 to 75dB. If you are not able to hear things properly, it is worthwhile to spend money on room acoustics.

You can, of course, write off what I say as the ramblings of an old fool, but there is proven scientific evidence of ear destruction because of sustained noise levels.

Take care.

Cheers
 

nitinbose

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Hi,
Check the cross-over frequency as well, maybe if you've set the cross-over at a higher limit than what the sub can handle, it could lead to distortion at high levels.

I believe you have two subs; do both subs show the same problem? If yes, do consider other possibilities as well. Try the subs with inputs from other audio sources other than LFE or from your DVD/bluray players.

Finally, as venkat suggested, be sure its your sub and not your ear(s). :)

cheers!

Nitin
 

psychotropic

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that does sound ridiculously loud if it's that high up on a logarithmic scale.....like venkat said, listening at those levels will damage your equipment and your ears.....so you might considering easing off on that volume knob.
 

nitinbose

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that does sound ridiculously loud if it's that high up on a logarithmic scale.....like venkat said, listening at those levels will damage your equipment and your ears.....so you might considering easing off on that volume knob.


Well, what if someone has a larger room, requiring such high levels? Furthermore, if your equipment can get damaged by high volume settings, why have them in the first place? That's what I dont understand, yet I surprisingly hear from several people.

Thanks,

Nitin.
 

psychotropic

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in an ideal world where one manufacturer made all components and matched them in a set and sold them......(like the consumer level companies do), they can build in various protection mechanisms to ensure that it never gets too loud or too anything in a way that causes damage.

However, in the world of even mildly high end audio, you're very unlikely to go for such a 'package deal', so your CD player might be from marantz, your amplifier from NAD and your speakers from Usher (yes, I speak for myself).

In such a case, what are you suggesting? how should the amplifier makers (or the speaker makers) calibrate their products ? Let the amp put out as much power as it reasonably can and hope that people are not stupid......or have protection circuitry kick in conservatively (like it happened with one of the forum members when he hooked up his Cyrus to his B&W)?

Anyways, there's no single answer to calibrating your protection circuitry or designing your components in a fail-safe way, and for this reason, neither the amp makers, not the speaker makers can ensure that "playing at max volume" will not damage the amp or speakers, simply because they have no idea what the user is going to pair their component with. They rely on users being sensible...which I don't think is too much to expect.....or is it?

Well, what if someone has a larger room, requiring such high levels? Furthermore, if your equipment can get damaged by high volume settings, why have them in the first place? That's what I dont understand, yet I surprisingly hear from several people.

Thanks,

Nitin.
 

venkatcr

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Well, what if someone has a larger room, requiring such high levels? Furthermore, if your equipment can get damaged by high volume settings, why have them in the first place? That's what I dont understand, yet I surprisingly hear from several people.

Irrespective of the size of the room, volume levels have to be kept at sane levels. You can get confused between volume levels and power of components. All amplifiers and speakers will distort at some level.

The larger the room, the more the power (in the amps) and the number and power handling capacity of the speakers that are needed. Depending upon room size, and your viewing distance, you can calculate the power that you need and the size and type of speakers that you get.

Imagine a cinema hall. There are some 20 speakers or more on the side and large speakers behind the screen. Most of the speakers behind the screen are of horn type as they have a longer throw. And they also use amplifiers that have powers in the league of 1000 watts. Irrespective of this, if you sit in the last row and there is a high level of collateral noise, you will not be able to hear dialogues properly. That is the reason that cinema halls are acoustically dead so that sound travels a longer distance without obstructions. But even in a environment like that, if the amps are pushed they will start distorting, and more important, hurting your ears.

Cheers
 
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nitinbose

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Hi,

I agree with you on the protection circuits which should trigger... However, in the process of reducing costs, manufacturers are also cutting short on various components!

i have a klipsch sub-12 sub-woofer, which has vibrating legs. Though the service person tried to solve it, the attempts were futile! I was also surprised to find that the legs were simply screwed to the wooden chassis, without any sheams or any firm methods! Plastic screwed to wood, creating vibratings during large sound passages - i bet it could also be the wood contracting during the cold weather.... clearly showing poor workmanship & materials used.

Thanks,

Nitin.
 

psychotropic

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apart from DIY audio and niche manufacturers.....unfortunately everything is built to a price......so depending on the price at which they plan to sell it they will cut the requisite corners :), and no corner is too sacred......design, materials, workmanship, assembly, testing, packaging....everything is fair game....of course, the better the company and the higher the price, the less of these corners you'll have the misfortune of encountering.

Hi,

I agree with you on the protection circuits which should trigger... However, in the process of reducing costs, manufacturers are also cutting short on various components!

i have a klipsch sub-12 sub-woofer, which has vibrating legs. Though the service person tried to solve it, the attempts were futile! I was also surprised to find that the legs were simply screwed to the wooden chassis, without any sheams or any firm methods! Plastic screwed to wood, creating vibratings during large sound passages - i bet it could also be the wood contracting during the cold weather.... clearly showing poor workmanship & materials used.

Thanks,

Nitin.
 

manu4panjab

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Manu:

I have some thoughts on your system and your use of your system.

1. See if you can open the face plate covering the sub's driver and visually inspect the driver for any damage.

2. Since your sub seems to come back to life after some 15 minutes of rest, this could be a case of overheating and clipping. The strange sound that you hear could be an amplified noise of some static or interference noise flowing into the sub. It could also be the sound of the overstressed and overloaded capacitor inside that is trying to empty itself.

3. Subwoofers work on a slightly different principle as compared to other speakers. For one they have their own amplifiers. The AVR sends a 'pre-out' to the sub which it amplifies internally. Just like other amplifiers, if you overload the amplifier from the source, it could trip. If there is no tripping mechanism, it is possible that the amp drives itself to destruction. If you are going to use nearly 50% of your AVR's power, first go to the the speaker set-up and set up the relative sound level of your sub very low. Then use the sub's amplifier pot behind the sub to set your desired output level.

4. Set the relative sound level of all speakers including sub to a max of 75dB using a SPL meter. You should do this using the test tone available in the AVR.

5. When you are doing this for the sub, you have to adjust both the sound level set up in the AVR and the amplifier pot in the sub. As I said before keep the sound level of the sub in the AVR to a very low level.

6. Use a power conditioner that is at least 1.5 times the max load capacity of your sub. It is also possible that your sub is not able to draw the required current from the mains. See if you also ensure that the power to the AVR and the one to the sub are from different switch boards.

After doing all this, run the system through a movie and see what happens. If things work well, your sub is all right.

I have mentioned this before, but listening to movies at insane volumes WILL destroy your ear. You will certainly get what is called 'Tinnitus'. This is a symptom where you hear a high pitched sound all the time. Additionally, your ear drums could become loose and flabby leading to a permanent deafness. Under no circumstances should the sound level of your system cross 80dB at the most. It is safer to keep it between 70 to 75dB. If you are not able to hear things properly, it is worthwhile to spend money on room acoustics.

You can, of course, write off what I say as the ramblings of an old fool, but there is proven scientific evidence of ear destruction because of sustained noise levels.

Take care.

Cheers

thanks for reply sir
no. 1 its very impossible to open the faceplate of polk psw 125 atleast for me i fear it might get torn apart
no.2 so sir does that means playing at super loud volumes destroy it and after that its always overheat even at low volumes i have tried low volumes levels but again after 15 to 20 mintues of playing it starts to loose depth very very much flat
no.3 sir i have set subwoofer volume knob to 9 o' clock and in avr subwoofer level is +2db which was done by audyssey should i turn down the sub level in avr menu too
no.4 sir idon't have spl metre
no.5 i already set my sub low
no.6 sir i have two v-gaurd stabilizer each has 1330 watts of power handling
one i use for onkyo 807 which has power equirments for 750 watts so multiply it with 1.5 1125 still room for 1330 watts of stab and 2nd one i use for sony projector which has 265 watts power requirment and polk psw 125 subwoofer which too has 265 watts of power requirment so both total 530 watts and multiply it with 1.5 is 795 watts so still enough room for v-gaurd 1330 watts so i'm safe i guess and i use two different switch but don't use two different switch boards should i use two diferrent switch boards ,i don't have two different switch boards in my ht only one board with six swicthes ans six plugs input but sir i have using this polk psw from past 8 months on same switch board and it creates problem from past two days ,should i use v-gaurd only with subwoofer and unplug the projector from it is using both projector and subwoofer on same stab obstruct current to pass for subwoofer
i completely understand but i'm not always listening to insane levels very few times :)

so sir i guess i have damage my sub right ,i'm waiting for ur reply sir
 
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manu4panjab

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Hi,
Check the cross-over frequency as well, maybe if you've set the cross-over at a higher limit than what the sub can handle, it could lead to distortion at high levels.

I believe you have two subs; do both subs show the same problem? If yes, do consider other possibilities as well. Try the subs with inputs from other audio sources other than LFE or from your DVD/bluray players.

Finally, as venkat suggested, be sure its your sub and not your ear(s). :)

cheers!

Nitin
hey bro i set crossover to 80 hz ,i have two polks before the first too has same problem but that one is completely produce lesser bass even when i set its volume knob to full so i sold it now this again what kind of possibilties bro is it playing at higher volumes damage it
 
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manu4panjab

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that does sound ridiculously loud if it's that high up on a logarithmic scale.....like venkat said, listening at those levels will damage your equipment and your ears.....so you might considering easing off on that volume knob.

bro my sub volume knob set to just 9'oclock
 

manu4panjab

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in an ideal world where one manufacturer made all components and matched them in a set and sold them......(like the consumer level companies do), they can build in various protection mechanisms to ensure that it never gets too loud or too anything in a way that causes damage.

However, in the world of even mildly high end audio, you're very unlikely to go for such a 'package deal', so your CD player might be from marantz, your amplifier from NAD and your speakers from Usher (yes, I speak for myself).

In such a case, what are you suggesting? how should the amplifier makers (or the speaker makers) calibrate their products ? Let the amp put out as much power as it reasonably can and hope that people are not stupid......or have protection circuitry kick in conservatively (like it happened with one of the forum members when he hooked up his Cyrus to his B&W)?

Anyways, there's no single answer to calibrating your protection circuitry or designing your components in a fail-safe way, and for this reason, neither the amp makers, not the speaker makers can ensure that "playing at max volume" will not damage the amp or speakers, simply because they have no idea what the user is going to pair their component with. They rely on users being sensible...which I don't think is too much to expect.....or is it?

mmm u r right bro
 

subhash

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--i am definetly the manu types

i wud love to play even louder without a hint of distortion
manu bhai has only touched 0 db (he has not mentioned the source here DVD/BRD), transformers 2 is a loud movie , i have hit +4 DB vol level on the same movie but on dvd with 875 onk and with external power amps

--manu try out blurays ,trust me with HD audio u will end up hitting the vol levels even higher but then with Blu rays u have issues
 
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