I am having an issue with my old Sony subwoofer. For a while now (until recently) I have been running my Polks without any supplemental bass and they sound great for musical content, though they lack the low end rumble needed for movies. I'm running the speakers on a stereo Sony Amp, and was attempting to hook up an older Sony sub that had basically been collecting dust for the past couple years.
Long ago, I had a Cambridge Soundworks 5.1 surround system. I purchased the surround set sometime around 2002 and it served me great for a while until the pots succumbed to dust and crackle. The surround set came with a 30W subwoofer with 4th order bandpass enclosure (box with a big port on the side) but the sub it came with was inadequate. So sometime in the early 2000s, I purchased a Sony 50w 8" Subwoofer that extends down into the mid 20Hz region.
Fast forward to a few weeks ago, I tried to match the sub to my Polks to help extend that low end bass. It seemed like the perfect marriage with the crossover tuned a quarter to full (50Hz-200Hz range) and the gain all the way up, and 180 phase. Well I was listening to some Bach Toccata and Fogue in D minor the other day, but it seemed like I wasn't feeling the heart-punching bass or heavy reverb of the largest organ pipes like I should.
My Sony brand Stereo amplifier has no dedicated line level output so I used the L/R speaker level inputs. Well more recently I started trying to fine tune it again and I couldn't hear any difference. It's like the subwoofer was just a placebo effect. Playing with the gain, x-over, and phase had almost no effect on the audio. So I took the cover off and noticed there was no visible travel on the sub at all. I cranked up the volume on the stereo receiver and there is visible movement on the Polk 5.25 inch woofers, no movement whatsoever on the sub itself. I place my hand on the subwoofer cone and I can feel minute vibrations, but they are not audible.
Line level input still works. Speaker level input appears dead, or the gain is so low that it has no appreciable effect. And that sub has a lot of travel. Back in the day, with my old sound system, that same powered sub used to rattle the China cabinet two rooms over.
But I gave up surround sound in 2013 when we remodeled the house. My mom did not want "wires" running all over the room, and I replaced the 5 crappy satellites (which had very poor midbass) with a stereo pair of HiFi speakers, and rummaged the 5.1 surround sound amp for a better stereo amp. Since then, we have been enjoying our movies in stereo, and two HiFi speakers sounds better than 5 crappy full ranges and an overcompensating sub.
Sadly, the speaker level inputs aren't outputting anything useful. Is the subwoofer just not sensitive enough, or did I burn something out by running too much power into it? The Sony stereo amp is rated 150w combined and the Polk speakers up to 125w each. Sub was only ever 50w with low bass extension. Despite the low wattage rating on the sub, I don't believe the driver has ever hit it's excursion limit. I've also never driven the Amp with max output. Volume goes up to 74; I think each increment is +1 dB. About the max I've ever driven it to with the Polks was 60. Normal music and TV listening is around 25-30. Movies and classical music, we usually crank it up to 35-40 due to the increased dynamic range. Around 55 is high enough to enjoy music on the patio in the back yard if I open the french doors. Beyond 60 is hearing loss I think. I can't tolerate that much loud.
I produced a Youtube video showing that the Polk speakers have far more displacement than the powered sub (using a 10Hz sine at low volume for visual cue) even with gain on the sub tuned to the maximum:
https://www.youtube.com/watch?v=IfbLeQ_lgXU
Is it time to retire the Sony sub? Any recommendation for replacements? Is the Dayton 12" sub any good, or are they just really big and really cheap? There's also a 15" version, but I would prefer deep bass over loudness:
https://www.parts-express.com/dayton-audio-sub-1200-12-120-watt-powered-subwoofer--300-629
https://www.parts-express.com/dayton-audio-sub-1500-15-150-watt-powered-subwoofer--300-634
I have a medium sized living room that connects to a smaller dining room, and would like something that goes low enough to appreciate the fundamental bass notes of a pipe organ, the most technically demanding instrument in all of classical music. My dad (may he rest in peace) played the organ at our old church for 35 years...
Long ago, I had a Cambridge Soundworks 5.1 surround system. I purchased the surround set sometime around 2002 and it served me great for a while until the pots succumbed to dust and crackle. The surround set came with a 30W subwoofer with 4th order bandpass enclosure (box with a big port on the side) but the sub it came with was inadequate. So sometime in the early 2000s, I purchased a Sony 50w 8" Subwoofer that extends down into the mid 20Hz region.
Fast forward to a few weeks ago, I tried to match the sub to my Polks to help extend that low end bass. It seemed like the perfect marriage with the crossover tuned a quarter to full (50Hz-200Hz range) and the gain all the way up, and 180 phase. Well I was listening to some Bach Toccata and Fogue in D minor the other day, but it seemed like I wasn't feeling the heart-punching bass or heavy reverb of the largest organ pipes like I should.
My Sony brand Stereo amplifier has no dedicated line level output so I used the L/R speaker level inputs. Well more recently I started trying to fine tune it again and I couldn't hear any difference. It's like the subwoofer was just a placebo effect. Playing with the gain, x-over, and phase had almost no effect on the audio. So I took the cover off and noticed there was no visible travel on the sub at all. I cranked up the volume on the stereo receiver and there is visible movement on the Polk 5.25 inch woofers, no movement whatsoever on the sub itself. I place my hand on the subwoofer cone and I can feel minute vibrations, but they are not audible.
Line level input still works. Speaker level input appears dead, or the gain is so low that it has no appreciable effect. And that sub has a lot of travel. Back in the day, with my old sound system, that same powered sub used to rattle the China cabinet two rooms over.
But I gave up surround sound in 2013 when we remodeled the house. My mom did not want "wires" running all over the room, and I replaced the 5 crappy satellites (which had very poor midbass) with a stereo pair of HiFi speakers, and rummaged the 5.1 surround sound amp for a better stereo amp. Since then, we have been enjoying our movies in stereo, and two HiFi speakers sounds better than 5 crappy full ranges and an overcompensating sub.
Sadly, the speaker level inputs aren't outputting anything useful. Is the subwoofer just not sensitive enough, or did I burn something out by running too much power into it? The Sony stereo amp is rated 150w combined and the Polk speakers up to 125w each. Sub was only ever 50w with low bass extension. Despite the low wattage rating on the sub, I don't believe the driver has ever hit it's excursion limit. I've also never driven the Amp with max output. Volume goes up to 74; I think each increment is +1 dB. About the max I've ever driven it to with the Polks was 60. Normal music and TV listening is around 25-30. Movies and classical music, we usually crank it up to 35-40 due to the increased dynamic range. Around 55 is high enough to enjoy music on the patio in the back yard if I open the french doors. Beyond 60 is hearing loss I think. I can't tolerate that much loud.
I produced a Youtube video showing that the Polk speakers have far more displacement than the powered sub (using a 10Hz sine at low volume for visual cue) even with gain on the sub tuned to the maximum:
https://www.youtube.com/watch?v=IfbLeQ_lgXU
Is it time to retire the Sony sub? Any recommendation for replacements? Is the Dayton 12" sub any good, or are they just really big and really cheap? There's also a 15" version, but I would prefer deep bass over loudness:
https://www.parts-express.com/dayton-audio-sub-1200-12-120-watt-powered-subwoofer--300-629
https://www.parts-express.com/dayton-audio-sub-1500-15-150-watt-powered-subwoofer--300-634
I have a medium sized living room that connects to a smaller dining room, and would like something that goes low enough to appreciate the fundamental bass notes of a pipe organ, the most technically demanding instrument in all of classical music. My dad (may he rest in peace) played the organ at our old church for 35 years...
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Bump. Okay guys, what do you think will be better?
Dayton 12"
https://www.parts-express.com/bic-venturi-v1220-12-powered-subwoofer-200w--303-432
Or the Bic?
https://www.parts-express.com/dayton-audio-sub-1200-12-120-watt-powered-subwoofer--300-629
Will these subs have any issue with the sensitivity of the Polks running them through the speaker inputs? My amplifier is stereo output only and no line level or sub outputs. I wanna get the Dayton 15" but it's probably too big for the space between the couch and the wall. We don't need an elephant in the room. Also for what it is worth, our living room is carpeted. Will the carpet dampen performance on a down-firing sub?
Also mods, this can probably move to Subwoofer forums, thanks...
Dayton 12"
https://www.parts-express.com/bic-venturi-v1220-12-powered-subwoofer-200w--303-432
Or the Bic?
https://www.parts-express.com/dayton-audio-sub-1200-12-120-watt-powered-subwoofer--300-629
Will these subs have any issue with the sensitivity of the Polks running them through the speaker inputs? My amplifier is stereo output only and no line level or sub outputs. I wanna get the Dayton 15" but it's probably too big for the space between the couch and the wall. We don't need an elephant in the room. Also for what it is worth, our living room is carpeted. Will the carpet dampen performance on a down-firing sub?
Also mods, this can probably move to Subwoofer forums, thanks...
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Sounds more like an issue with the amplifier than the speaker itself. Generally if the speaker doesn't rub or make noise it should be ok. I would instead investigate the high level input instead. The speaker level input in most amplifiers are simply a resistor divider that reduces the voltage to line level. It would be more likely these resistors have been overheated and gone entirely open or have increased resistance dramatically. I would pull the amp out and investigate the components directly connected to the high input.
Strangely, I pulled the sub out of the chain and connected it to my Lanai 2020TI Amp and full range birdhouse speakers. I cranked the gain up and the subwoofer bounced like mad, and at much lower listening levels than what I used with the Polks in the other room. Sounded balanced with the crossover at maximum (150Hz) and the gain in about the 8-9 o'clock position. Obviously the crossover for the Polks will be far lower.
If all goes well, I'll hook it back up tomorrow. We had an electrical storm last weekend, and the lights flickered on and off, and my touchlamp went baslistic from the EMP pulses. I suspect the electrical storm may have knocked the sub offline and physically unplugging it and moving it to the next room (the physical plug, not the power switch) somehow fixed it?
We do have a high end surge protector on the entertainment center and a lightning arrestor on the cable line. My particular model is supposed to be fail safe, ie it will not operate once it's capacity to absorb surges is gone. Either that or playing at too high volume temporaily "nuked" the speaker terminal inputs? Sometimes you just have to unplug stuff from the wall for a few minutes before it will work again...
Now learn that most who make recommendations are only educated by advertising and hearsay. A high end protector (ie $100) is electrically similar to one selling in Walmart for $10. Subjective reasoning is why scams are so profitable and successful.
Second, protector located adjacent to appliances (and too far from earth ground) can make surge damage easier. Nothing new. But most do not first learn facts. Most assume surge protector sounds like surge protection. So it must be same.
Third, something completely different and called a surge protector is why even direct lightning strikes do not even harm the protector.
How to know? Honest recommendations always discuss specification numbers. Then discover high end protectors only have high end profit margins. How many other at risk appliances (furnace, clocks, dishwasher, bathroom and kitchen GFCIs, central air, refrigerator, smoke detectors, recharging electronics) without protectors were not damaged?
The surge protector was only $60, purchased in 2005 for a computer system. Tripp Lite. To me, that's a high end protector. 😛
I've got the old sub plugged in and working. Kinda slightly disappointed however as I wanted to get that Dayton 12" sub from PE, but since the old one works, I have no excuse. right now I've got the phase set to 180, xover set to half, gain at 10 o'clock. I played some audio samples with 20-200Hz and 20-20000Hz log sine sweeps and the system is perfectly balanced now. I'm gonna delete the video now since it's pointless.
I've got the old sub plugged in and working. Kinda slightly disappointed however as I wanted to get that Dayton 12" sub from PE, but since the old one works, I have no excuse. right now I've got the phase set to 180, xover set to half, gain at 10 o'clock. I played some audio samples with 20-200Hz and 20-20000Hz log sine sweeps and the system is perfectly balanced now. I'm gonna delete the video now since it's pointless.
That Tripplite is electrically similar to one selling in Walmart for $10. Paying $60 sound more like a scam; not high end.
Read its specification numbers. Tiny joules. That is not high end. Price never defines high end. Specs numbers do.
It's similar to this model:https://www.amazon.com/Tripp-Lite-Protector-INSURANCE-ISOBAR6ULTRA/dp/B0000513US/
but it's solid black and has cable and modem jacks on it as well.
Unlike certain well known cable manufacturers, they aren't selling snake oil for hundreds of dollars per foot. It have six outlets and three isolation transformers, something cheaper protectors generally lack. Also all steel construction. The desktop system it was once connected to is now protected by UPS. Anyway I think $60 was a fair price at the time of purchase in 2005.
BTW it's working beautiful now. No auto mode so I just leave it on 24/7. Still not sure if it was the thunderstorm or me possibly overloading the sub by playing too loud. Also I did the AA test on my Polks and the Sony sub. With red = +1.5v, the Polk woofer pushes and the sub pulls. So 180 degree is absolutely the correct setting.
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That Tripplite is recommended by ignoring numbers. Again, where is the joule number?
That UPS does not even claim to protect hardware. Again, what do its spec numbers say.
Best isolation transformer is already inside electronics. However, a Tripplite can compromise what is already best protection inside electronics. Other isolation transformers cannot block that potentially destructive path.
Many hear Tripplite is good protection. Somehow that proves a Tripplite is effective - because it was the first thing heard. A $60 Tripplite or $100 Monster is electrically equivalent to one selling in Walmart for $10. Tripplite is promoted without spec numbers - the first indication of a scam. Second, protector located adjacent to appliances (and too far from earth ground) can make surge damage easier. Third, something completely different and called a surge protector is why even direct lightning strikes do not even harm the protector.
Other manufacturers known for integrity sell effective solutions. These cost about $1 per protected appliance. How much did you pay for a Tripplite that can even compromise better protection inside
That UPS does not even claim to protect hardware. Again, what do its spec numbers say.
Best isolation transformer is already inside electronics. However, a Tripplite can compromise what is already best protection inside electronics. Other isolation transformers cannot block that potentially destructive path.
Many hear Tripplite is good protection. Somehow that proves a Tripplite is effective - because it was the first thing heard. A $60 Tripplite or $100 Monster is electrically equivalent to one selling in Walmart for $10. Tripplite is promoted without spec numbers - the first indication of a scam. Second, protector located adjacent to appliances (and too far from earth ground) can make surge damage easier. Third, something completely different and called a surge protector is why even direct lightning strikes do not even harm the protector.
Other manufacturers known for integrity sell effective solutions. These cost about $1 per protected appliance. How much did you pay for a Tripplite that can even compromise better protection inside
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Forget the Tripp Lite. I feel like jokes are being made at my expense somehow. Lightning does not have to strike the line to cause chaos. Everytime lightning strikes earth somewhere, it sends an EMP pulse. These EMP are wireless energy that propagates walls and any conductor that isn't shielded to Earth ground, acts as an antenna to EMP radiation. Ultimately, none of our electronic devices are radiation hardened, so if a bit gets flipped somewhere as a result of a lightning EMP, than that device may cease to function momentarily even if no real damage to the electronics has resulted.
Typically unplugging the device fixes it. I've had to reset the cable box and DSL modem several times in this manner. The Sony amp even quit once and refused to turn on through the remote or the power button. Unplugging the device fixed it. I also have a touch lamp shaped like a Mario question block, that is especially sensitive to lightning EMP, and goes berserk whenever we have a storm. It plays audio effects too, so we can hear it activating multiple times even if in the other room.
Past two years, we get more frequent rainfalls and storms in Louisiana, and three record breaking floods within a year of each other (not affecting our area specifically), and now the mildest winter on record, and the past few weeks got a lot of storms. It's almost like 3 months fall, 3 months spring, 6 months summer. Global warming at work folks...
There is also a very real possibility that a 50w powered sub tuned to a pair of highly sensitive 8 ohm Polk speakers (125w each, 89dB nominal) and a stereo Sony amplifier (200w total) and connected to the speaker level outputs, that over-driving the internal sub amp via speaker level input may cause it to go into some kind of "protect" mode. That 12" Dayton sub still looking tempting though, and I could use the old sub to supplement my bedroom stereo (with nice Jensen JP-500 rugged bookshelf monitors). All the stuff at Best Buy is $200-$400 bucks and nothing goes below 30Hz. Even my old $100 50w Sony (purchased at Best Buy some 15 years ago) goes deeper than that with an 8" long throw driver, but the cone is massive for it's size and has Xmax of around an inch. Increased mass = lower Fs and I'll take deep over loud.
All I know is the subwoofer did not function properly until after I disconnected it and moved it into another room. It's now connected to a separate outlet in the same room, with a different surge protector, because I moved it to the right hand corner (better room loading characteristics) and the cord reached this other outlet more easily. Ironically, the surge protector I have it plugged into now was a cheapo unit I have owned since 1999. According to the LED indicators, it's still good.
Typically unplugging the device fixes it. I've had to reset the cable box and DSL modem several times in this manner. The Sony amp even quit once and refused to turn on through the remote or the power button. Unplugging the device fixed it. I also have a touch lamp shaped like a Mario question block, that is especially sensitive to lightning EMP, and goes berserk whenever we have a storm. It plays audio effects too, so we can hear it activating multiple times even if in the other room.
Past two years, we get more frequent rainfalls and storms in Louisiana, and three record breaking floods within a year of each other (not affecting our area specifically), and now the mildest winter on record, and the past few weeks got a lot of storms. It's almost like 3 months fall, 3 months spring, 6 months summer. Global warming at work folks...
There is also a very real possibility that a 50w powered sub tuned to a pair of highly sensitive 8 ohm Polk speakers (125w each, 89dB nominal) and a stereo Sony amplifier (200w total) and connected to the speaker level outputs, that over-driving the internal sub amp via speaker level input may cause it to go into some kind of "protect" mode. That 12" Dayton sub still looking tempting though, and I could use the old sub to supplement my bedroom stereo (with nice Jensen JP-500 rugged bookshelf monitors). All the stuff at Best Buy is $200-$400 bucks and nothing goes below 30Hz. Even my old $100 50w Sony (purchased at Best Buy some 15 years ago) goes deeper than that with an 8" long throw driver, but the cone is massive for it's size and has Xmax of around an inch. Increased mass = lower Fs and I'll take deep over loud.
All I know is the subwoofer did not function properly until after I disconnected it and moved it into another room. It's now connected to a separate outlet in the same room, with a different surge protector, because I moved it to the right hand corner (better room loading characteristics) and the cord reached this other outlet more easily. Ironically, the surge protector I have it plugged into now was a cheapo unit I have owned since 1999. According to the LED indicators, it's still good.
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Everytime lightning strikes, then wrist watches, automobile radios, cell phones, car computers, etc are damaged by EMP? EMP is hype that lives on when one does not learn of E-M fields and fears without first learning numbers. EMP is only hyped by subjective reasoning - also called junk science reasoning.
Lightning struck a rod. Maybe 20,000 amps traveled down its hardwire to earth. Only four feet away from that hardwire was an IBM PC - that did not even blink. Neither did any other electronics. EMP could not be larger - that lightning current was only four feet away. No hardware damage. Software did not even crash. Massive EMP did no harm.
Anything that is protected from direct lightning strikes obviously is protected from trivial EMP threats. If protection does not exist for direct lightning strikes, then effective protection does not exist.
Unplugging is also dependent on a most unreliable item in every house. Protection must exist in every microsecond of every 24 hours. Does not exist if one must unplug a dishwasher, all CFL & LED bulbs, central air, bathroom and kitchen GFCI, refrigerator, clocks, furnace, and every smoke detector. Those cannot be unplugged? Then EMP (and other surges) must be routinely destroying all? Of course not. Robust protection inside all appliances make trivial (but feared) EMP irrelevant. Only a tens or 100 times less expensive 'whole house' solution protects all from potentially destructive anomalies.
Why would anyone depend on a human holding plugs every microsecond in 24 hours while never sleeping, performing body maintenance, doing chores, or earning money? Unplugging is a myth dependent on a most unreliable solution - that also cannot unplug everything - that is not there every microsecond.
How does that human know a surge, created by stray cars, tree rodents, linemen errors, or utility switching, will happen? More reasons why unplugging is unreliable.
A safety lockout feature is found in more expensive electronics. That lockout is cleared only when its power cord is completely disconnected for a short period. We learned about junk science conclusions in elementary school science. A conclusion only from observation is classic junk science. Also required is a hypothesis. By not combining how electronics work with that observation, then classic junk science reasoning exists.
Essential to protect household appliances is one properly earthed 'whole house' protector. Even plug-in protectors (ie high profit, tiny joule Tripplite) require protection only provided by a long (over 100 year old) proven solution. That solution is for one anomaly (that may occur once every seven years). Other anomalies require other and different solutions. Some solutions are routinely found inside electronics. Even 'dirty' power from a UPS in battery backup mode is made irrelevant by protection routinely found inside all electronics.
EMP is a mythical fear once experience is combined with facts and numbers. Safety lockout explains other observations.
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Okay, I get your point. But multiple times during an electrical storm we have had electronics malfunction in such a manner that unplugging the device and cold booting it fixed the anomaly. My 8-bit-lit question block lamp often goes berserk during storms. The capacitive touch sensor is tuned way too sensitive such that it detects a human hand one inch from the base.
The threshold for permanent damage is much, much greater than the threshold for software error. Hence the equipment malfuntions after a storm but is restored after power cycling the hardware. A cloud to ground lightning discharge generates full scale electromagnetic radiation all the way from audio frequencies to radio waves to visible light to Xray. When I was a kid, I would tune my mom's short wave radio to blank frequencies during a storm and "listen" to the lightning.
Lightning absolutely creates an EMP event every time it strikes ground nearby. My overly sensitive novelty lamp is a testament to this.
https://www.8bitlit.com/
Just because an EMP is not powerful enough to "nuke" a device doesn't mean it can't impact operation somehow. This isn't like place-electronic-device-in-a-microwave level of instant destruction, but the pulses do exist. Atomic bomb testing during the cold war era absolutely reeked havoc on radios and other devices, however these were mostly analog in nature, so the errant signals quickly dissipated. A digital device can get knocked into an invalid state of operation by such a pulse, ie a microcontroller or other digital circuit gets locked up and power source must be removed so that the device can re-initialize.
Typically the digital inputs in chips have reverse bias diode protection built in so that an input spike outside of operating parameters will not lead the junction into breakdown, ie an errant "pulse" gets dumped to Ground or VCC and is not strong enough to overwhelm the electronics. The filter caps connected between the DC terminals safely absorb the pulse without permanent damage. However, the EMP event can cause bits to flip resulting in irrecoverable error. Cold booting will reset this.
The surge protector only clamps at 330 volts, which is close to the peak level of 240V RMS, twice what the 120V equipment connected to the strip is rated for. It doesn't prevent HF noise from entering the lines, nor will it protect the leads connected to devices acting as little antennas to channel EMP inside the shielded case. Most quality built hifi audio equipment have steel case acting as Faraday cage to protect from interference, but this is primarily to prevent audible noise or HF degradation of signals.
The threshold for permanent damage is much, much greater than the threshold for software error. Hence the equipment malfuntions after a storm but is restored after power cycling the hardware. A cloud to ground lightning discharge generates full scale electromagnetic radiation all the way from audio frequencies to radio waves to visible light to Xray. When I was a kid, I would tune my mom's short wave radio to blank frequencies during a storm and "listen" to the lightning.
Lightning absolutely creates an EMP event every time it strikes ground nearby. My overly sensitive novelty lamp is a testament to this.
https://www.8bitlit.com/
Just because an EMP is not powerful enough to "nuke" a device doesn't mean it can't impact operation somehow. This isn't like place-electronic-device-in-a-microwave level of instant destruction, but the pulses do exist. Atomic bomb testing during the cold war era absolutely reeked havoc on radios and other devices, however these were mostly analog in nature, so the errant signals quickly dissipated. A digital device can get knocked into an invalid state of operation by such a pulse, ie a microcontroller or other digital circuit gets locked up and power source must be removed so that the device can re-initialize.
Typically the digital inputs in chips have reverse bias diode protection built in so that an input spike outside of operating parameters will not lead the junction into breakdown, ie an errant "pulse" gets dumped to Ground or VCC and is not strong enough to overwhelm the electronics. The filter caps connected between the DC terminals safely absorb the pulse without permanent damage. However, the EMP event can cause bits to flip resulting in irrecoverable error. Cold booting will reset this.
The surge protector only clamps at 330 volts, which is close to the peak level of 240V RMS, twice what the 120V equipment connected to the strip is rated for. It doesn't prevent HF noise from entering the lines, nor will it protect the leads connected to devices acting as little antennas to channel EMP inside the shielded case. Most quality built hifi audio equipment have steel case acting as Faraday cage to protect from interference, but this is primarily to prevent audible noise or HF degradation of signals.
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And again, that anomaly triggers a safety lockout. A short AC voltage dropout would trigger that (your) symptom.
Simplest electronics do not have a watchdog timer and voltage supervisor. These cheap designs assume once voltage drops too low, then a full blackout and 'power on reset' will occur. So again, a short AC voltage dropout would trigger that symptom.
Unfortunately, many do not learn how this stuff works. Then fables about EMP and surges are widely promoted. Wild fables are routine with soundbyte logic. Many paragraphs are required to explain realities such as a safety lockout or watchdog timer.
If EMP created significant currents through electronics, then radios with antennas, optimized to maximize an E-M field affect (to create microvolts), would be blown through destructively by that EMP field. Another example, with numbers, that blows always EMP myths - justified only by subjective reasoning.
Another example - since so many were ignored. A lightning strike maybe 10 meters from an antenna (resulting in a massive EMP), might create a thousand plus volts on that antenna. An NE-2 (neon glow lamp - a milliamp device) is put on that antenna lead. Then thousands of volts drops to maybe 60 volts. Why? A milliamp NE-2 easily conducts EMP currents - resulting in near zero voltages. EMP power is so tiny as to be eliminated even in wrist watches.
Again, numbers that are ignored by using subjective rationalizations. No numbers says wild speculation and fables are promoted as knowledge. Fear of EMP is promoted by science denial - subjective reasoning.
Another example of why numbers must always be provided. A 330 let-through voltage is not a magic number for 120 volt protection. No protector 'clamps' at 330 volts. Any layman can read MOV datasheet graphs. 330 volts is a ballpark number for a constant voltage that will quickly degrade an MOV (an acceptable failure mode). AC voltages must remain well below that number. MOV does significant protection when voltages well exceed 500 volts. Again, don't take my word for it. View layman simple graphs. Confirm those numbers.
Providing a 330 let-through number means significance (perspective) can be discussed. Every question or supposition must include perspective - numbers. Then 330 volts is explained. Providing that number was important.
EMP is made irrelevant by what must exist inside all electronics. However lightning can cause multiple, short AC power interruptions. That can trigger a safety lockout. Or cause voltage problems in cheaper electronics without voltage supervisors and watchdog timers. It is probably a power interruption; not EMP. Definitely not EMP from lightning 5 miles away.
Fundamental facts (called a hypothesis in junior high science) must be known long before making any conclusion from an observation. Conclusions only from observation is junk science as introduced in elementary school science.
Let's put numbers to that reverse biased protection diode. Semiconductor interface circuits can be destroyed by 60 volts. That same semiconductor may withstand 2000 or 15,000 volts without damage ... when part of a system. Numbers are at the top of a datasheet's first page:
http://datasheets.maxim-ic.com/en/ds/MAX1487E-MAX491E.pdf
Another example of robust protection routinely found inside electronics.
Another example of why paragraphs (with numbers) are required to expose and debunk soundbyte rumors. EMP fears only exist when subjective reasoning - no numbers - creates those urban myths.
So momentary brownouts or power failures, likely due to shorts further up the grid, causes the electronics to go into a safety lockout? That's plausible. Often when a short occurs within the power grid, a dip in output happens because the system is overwhelmed, and the self-resetting circuit breaker trips, removing the load. Sometimes when we are on the affected branch circuit, the self-resetting breaker will re-activate, and if the short condition still exists (as is often the case with a downed line) will immediately re-trip. This can cause the lights to flash momentarily, often several times as the grid attempts to correct itself. Last few times we had T-storms, the power did not go out, just momentary light flickers.
I will say that EMP events do exist, and my novelty lamp detects it, whether said events are responsible for malfunctions or not. Sometimes the tiny spark created in a wall switch elsewhere in the house is enough to cause the touch lamp to activate.
And the fact that an FM radio antenna picks up microvolt signal levels in the tuning range, does not mean that a large signal a couple orders of magnitude stronger, ie a few millivolts or even volts will destroy the pickup electronics. A large signal will firstly get filtered by the LC tuning circuit, or whatever tuner type is in place if digital. so if the signal isn't in the band the radio is tuned to, it will get rejected. Most quality tuners have incredibly high Q factors such that all but the most powerful adjacent channels get rejected. Secondly, the base on the transistor can be exposed to voltage transients in excess of what the transistor is capable of receiving; this places the transistor into saturation region. Transistor amplifiers can be safely operated in saturation region without damage to the transistor (though this can wreak havoc on audio circuits and potentially damage the HF driver in multi-way speakers), in fact bipolars can easily be employed as switching transistors and operated exclusively in this mode, though mosfets are more suited to this purpose. One of two ways a large signal on a receiving transistor can destroy it, either by causing too much current to pass across the junction, or if the input signal exceeds the breakdown voltage of the transistor, typically 30V or more.
So your radio antenna would need voltages in excess of 30V from the EMP, or currents closer to the ampere range rather than milliamp or microamps. A direct strike would more than satisfy this requirement, far away not so much.
I will say that EMP events do exist, and my novelty lamp detects it, whether said events are responsible for malfunctions or not. Sometimes the tiny spark created in a wall switch elsewhere in the house is enough to cause the touch lamp to activate.
And the fact that an FM radio antenna picks up microvolt signal levels in the tuning range, does not mean that a large signal a couple orders of magnitude stronger, ie a few millivolts or even volts will destroy the pickup electronics. A large signal will firstly get filtered by the LC tuning circuit, or whatever tuner type is in place if digital. so if the signal isn't in the band the radio is tuned to, it will get rejected. Most quality tuners have incredibly high Q factors such that all but the most powerful adjacent channels get rejected. Secondly, the base on the transistor can be exposed to voltage transients in excess of what the transistor is capable of receiving; this places the transistor into saturation region. Transistor amplifiers can be safely operated in saturation region without damage to the transistor (though this can wreak havoc on audio circuits and potentially damage the HF driver in multi-way speakers), in fact bipolars can easily be employed as switching transistors and operated exclusively in this mode, though mosfets are more suited to this purpose. One of two ways a large signal on a receiving transistor can destroy it, either by causing too much current to pass across the junction, or if the input signal exceeds the breakdown voltage of the transistor, typically 30V or more.
So your radio antenna would need voltages in excess of 30V from the EMP, or currents closer to the ampere range rather than milliamp or microamps. A direct strike would more than satisfy this requirement, far away not so much.
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