Was looking for a link to a site that would explain why subwoofers blow, and why amps go. I'm looking for easy to read and understand info, so I can explain it to people so they don't think I am nuts.
thanks
Blowing subs - info needed
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Typhoonk
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Blowing subs - info needed
Hi;
Was looking for a link to a site that would explain why subwoofers blow, and why amps go. I'm looking for easy to read and understand info, so I can explain it to people so they don't think I am nuts.
thanks
Was looking for a link to a site that would explain why subwoofers blow, and why amps go. I'm looking for easy to read and understand info, so I can explain it to people so they don't think I am nuts.
thanks
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Got to sell one of my cars to cover the bills
2002 Mazda Protege 5 - Manual, Blue colour fully loaded
PM for info
Got to sell one of my cars to cover the bills
2002 Mazda Protege 5 - Manual, Blue colour fully loaded
PM for info
It's quite simple. Amplifiers don't blow subs. Subs blow amplifiers. Distortion blows subs as well as prolonged exposure to excessive wattage and incorrect box tuning.
Distortion can blow subs by causing excessive uncontrolled movement of the sub, creating excessive heat which in turn can burn, unravel and sometimes melt the coil.
Excessive wattage can cause the same symptoms listed above.
Incorrect box tuning can cause the speaker to have a lack of control therefore bottoming out which will unseat the coil winding when the bobbin is bent and or possibly unload the sub on the up stroke.
Amps can blow once any or all these conditions are present because power is non directional, what happens is the sub sends feedback back to the amp usually causing the amp to clip and go into protection and or just blow up.
Distortion can blow subs by causing excessive uncontrolled movement of the sub, creating excessive heat which in turn can burn, unravel and sometimes melt the coil.
Excessive wattage can cause the same symptoms listed above.
Incorrect box tuning can cause the speaker to have a lack of control therefore bottoming out which will unseat the coil winding when the bobbin is bent and or possibly unload the sub on the up stroke.
Amps can blow once any or all these conditions are present because power is non directional, what happens is the sub sends feedback back to the amp usually causing the amp to clip and go into protection and or just blow up.
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lakersfan1
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It's not as easy to say distortion blows a sub.
When you drive an amplifier past its limits, it will clip the sine wave.
When this is done, it will drive the sub to power levels past that of the amp. This is because where the sine squares off, the sub will still be trying to travel in the direction where it has momentum. For a 500 watt amplifier, for instance, you may push a sub to excursion levels approximating a 700 or 800 watt amp when clipping the signal.
You have to really be pushing the limits of a sub with the current amp to blow it by this means. It's more common to blow a tweet with distrotion because the squared off sine wave in an active system can show as a low freqency wave that the tweeter that it is not designed to play and you end up blowing the magnet out its gap.
For subs, it's usually more common to blow by them by installing them in an improperly sized enclosure for the power available, or tuning a ported enclosure too high.
If you make a sealed box too large, it will allow the sub more excursion at lower frequencies with the same power. However, make it too small, and your sub will sound like crap.
For ported boxes, alot of manufacturers will give a high tuning frequency to satisfy the listening habits of bass heads. The problem with this is the spring effect of the box is zero below the tuning frequency of the port, so excursion goes through the roof. If someone plays low frequency material like bass cello or organ on a sub tuned for dance music or SPL contests, they're likely to blow thier sub. It's generally better safe than sorry to tune in the 20Hz-30Hz range on a ported box for daily listening to keep cone excursion in check.
When you drive an amplifier past its limits, it will clip the sine wave.
When this is done, it will drive the sub to power levels past that of the amp. This is because where the sine squares off, the sub will still be trying to travel in the direction where it has momentum. For a 500 watt amplifier, for instance, you may push a sub to excursion levels approximating a 700 or 800 watt amp when clipping the signal.
You have to really be pushing the limits of a sub with the current amp to blow it by this means. It's more common to blow a tweet with distrotion because the squared off sine wave in an active system can show as a low freqency wave that the tweeter that it is not designed to play and you end up blowing the magnet out its gap.
For subs, it's usually more common to blow by them by installing them in an improperly sized enclosure for the power available, or tuning a ported enclosure too high.
If you make a sealed box too large, it will allow the sub more excursion at lower frequencies with the same power. However, make it too small, and your sub will sound like crap.
For ported boxes, alot of manufacturers will give a high tuning frequency to satisfy the listening habits of bass heads. The problem with this is the spring effect of the box is zero below the tuning frequency of the port, so excursion goes through the roof. If someone plays low frequency material like bass cello or organ on a sub tuned for dance music or SPL contests, they're likely to blow thier sub. It's generally better safe than sorry to tune in the 20Hz-30Hz range on a ported box for daily listening to keep cone excursion in check.
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mr1in6billion
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Typhoonk
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Appreciate the replies. I'm looking for a REALLY easy explanation on why a sub blows - instead of just saying "The problem is sitting in the front seat"
I found this site http://www.ofsoundmind.com/
Very low tech talk, and I believe even audio guys without a lot of knowledge of electricity or sound (backyard or flea market installers), should understand this if they've missed something elsewhere.
I found this site http://www.ofsoundmind.com/
Very low tech talk, and I believe even audio guys without a lot of knowledge of electricity or sound (backyard or flea market installers), should understand this if they've missed something elsewhere.
-------------------------------------------------------
Got to sell one of my cars to cover the bills
2002 Mazda Protege 5 - Manual, Blue colour fully loaded
PM for info
Got to sell one of my cars to cover the bills
2002 Mazda Protege 5 - Manual, Blue colour fully loaded
PM for info
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lakersfan1
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- Joined: June 26th, 2003, 2:01 am
- Location: Puyallup, WA
You want the short yellow bus version? Because each sub is made to move so many millimeters in each direction. If you put too much power or the wrong box, you risk shooting the voicecoil out of the gap and/or ripping the spider and/or ripping the surround.Typhoonk wrote:Appreciate the replies. I'm looking for a REALLY easy explanation on why a sub blows - instead of just saying "The problem is sitting in the front seat"
Last edited by lakersfan1 on June 30th, 2007, 10:44 pm, edited 1 time in total.
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lakersfan1
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94mx3precidia
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