Hi All,
Inhad the power company install a device into the power meter in the outside of the house. It provides protection from lighting strikes. It is billed extra monthly. This along with Furman protection for system.
Power amps into surge protector/Conditioner or DIRECT to wall? Final verdict?
Golly. What a fascinating thread. Just wanted to chime in and share my very recent experience with a Lithium-Ion battery powered generator. I think this is a kind of confusing name, and I was happy to see someone mention this technology on page 2 of this thread. The brand I tried was a Goal Zero, model Yeti 1400. They have other models which use lead acid (car type) batteries which are less expensive. Much heavier, too.Anyway, in my system the beneficial impact of the Yeti was remarkable. I didn't know I had any noise in my system but it reduced the noise floor significantly, allowing microdynamics and nuances and musically important details to come through much more clearly. It was great and, IMHO, was more effective at reducing noise than the very larger Furman 15i or whatever it was I subsequently borrowed from my dealer. |
1) I will admit they use it ONCE. It is not in the US trademark registry, so I’m unsure that it is still officially registered.- Don’t need to register a trademark technically, but whether you admit it or not, you would be wrong: http://tmsearch.uspto.gov/bin/showfield?f=doc&state=4808:lh0t5p.3.5 2) One of the patents still covers the original concept. Patents can expire. The series mode surge technology patent states, "Provides an inductor system as the first means of protection." Furman’s SMP uses a MOV as the first means of protection. Nope, that is not how patents work. The original patents, which is the basis for what SurgeX called series mode, were filed in the 80s. You cannot protect anything that was in those original patents. Putting a MOV in front of the inductor does not negate the use of the same technology after the MOV. It is an improvement, not a limitation. 3A) Through the use of capacitors and resistors, a series mode product releases current back to the neutral wire. This actually provides a sort of passive power factor correction. Depending on the power conditions and the load, greater power could be provided. Plus, no one said you have to plug an amplifier into it. Incorrect. The capacitor bleeds power via a large value resistor. This will provide no effective change on the power factor, good or bad. It will not increase the power available in any effective way. I didn’t say it had to be plugged into an amplifier, but I was noting that the technology has application issues. 3B) "Power line surges within a building may be as large as 6,000 Volts, 3,000 Amperes, with a duration of 50 microseconds, according to the industry standard ANSI C62.41." No, that is not what ANSI C62.41.1 says. It is mainly a discussion around the data, much of it poor, and potential probabilities. The 1.2/50us voltage, 8/20us current combination wave was from a previous spec, but was found to be reasonable. The 6KV was arrived at by a combination of some data showing 4kv strikes at a maximum rate of 0.1/year in some indoor installation, and a typical arc-over AC wiring of 6KV, hence providing a natural spark-gap protection. By interior of the building, they mean some distance from the service panel, and the 6KV/3KA is really industrial, with residential defined in C62.41 much lower ... the reality is, hits much greater than 2KV/1KA are quite rare residential, but if you get a local lighting hit, you can get hit with more than 6KV/3KA. •IEEE defines its harshest interior surge environment as one that could experience 100 surges of 6000V, 3000A in a years time (category B3). No, the IEEE documents most definitely do not say that. They actually discuss high incidences of B3 ringwaves, 6KV/500A, 100KHz, which are induced by motor starting, large breakers turned on, etc. in heavy industrial and large commercial settings, never in a residential application like home audio / video. •UL (Underwriters Laboratories) now provides a new adjunct testing service (in addition to the 1449 safety classification) that will test surge protectors to the 1000 surge, 6000V, 3000A federal protocol." Looking at the most recent 1449 ... nothing in there about that. That said, you can always get UL or anyone else to do a test like this. Real series mode surge protectors are the only devices rated with the A-1-1 certification. If you are just going to cut and paste from SurgeX literature, what is the point? The Grade A-1-1 was from a US Government procurement document that was withdrawn over 15 years ago! The only one who puts that into their literature is SurgeX. For the record, a 50KA MOV, which in terms of audiophile equipment is not very expensive, will withstand 1000+ 6KV/3KA hits. •Mode 1 is Line to Neutral (L-N) suppression. This avoids ground wire contamination and is recommended for interconnected equipment." Ya, no. Recommended by SurgeX maybe because they cannot protect Line/Neutral to ground, and considering most would be plugged into the same power bar/surge protector this makes not sense. Line/Neutral to Ground surges can be very damaging. A big common mode surge on Line/Neutral causes a rise of the potential of all the electronics in the chassis, then you get a spark from the electronics to the grounded metal ... and poof ...
Their inductor is actually fairly substantial, and the winding are heavy. Unless you can compare the two inductors for value and saturation current, your comment is at best a guess. 4) Why would I apologize? Furman still lost, and your argument is a red herring. Furman’s SMP is not real Series Mode® surge technology. From your earlier referenced material: No, they didn’t "lose". They settled, and remember both were suing each other. No details of whatever agreement they arrived at were ever discussed. Furman likely changed the name to avoid wasting money on lawyers fees with little benefit. The total value of SurgeX was $2.5 mill when sold in 2006. He also recognized that the act of shunting the surge to ground pollutes the ground with energy that often enters the sound or video system. This was causing equipment disruption, malfunctions, error-codes, reboots, and downtime that degraded performance and increased dealer costs. The MOV does not even engage till well over the line voltage, it would not shunt anything, and you could shunt to ground with a GDT (which all of Europe does) and solve this issue if you were truly concerned.. The simple reality is this technology cannot be used on L/N to ground coupling modes because it would violate leakage current requirements (and be very expensive). |
@atduffid 1) I will admit they use it ONCE. It is not in the US trademark registry, so I’m unsure that it is still officially registered. 2) One of the patents still covers the original concept. Patents can expire. The series mode surge technology patent states, "Provides an inductor system as the first means of protection." Furman’s SMP uses a MOV as the first means of protection. 3A) Through the use of capacitors and resistors, a series mode product releases current back to the neutral wire. This actually provides a sort of passive power factor correction. Depending on the power conditions and the load, greater power could be provided. Plus, no one said you have to plug an amplifier into it. 3B) "Power line surges within a building may be as large as 6,000 Volts, 3,000 Amperes, with a duration of 50 microseconds, according to the industry standard ANSI C62.41." "•IEEE (The Institute of Electrical and Electronic Engineers) states that 6000V is the largest transient that the interior of a building would experience. •IEEE defines its harshest interior surge environment as one that could experience 100 surges of 6000V, 3000A in a years time (category B3). •A new federal guideline recommends that a surge protector utilized in a harsh environment should be capable of withstanding 1000 surges of 6000V, 3000A or ten years worth of IEEE’s category B3. •UL (Underwriters Laboratories) now provides a new adjunct testing service (in addition to the 1449 safety classification) that will test surge protectors to the 1000 surge, 6000V, 3000A federal protocol." Real series mode surge protectors are the only devices rated with the A-1-1 certification. "A-1-1 Certification The U.S. Government’s highest classification for surge suppression." "•Grade A is the best endurance – 1,000 surges of 6,000 Volts / 3,000 Amps with no degradation. •Class 1 specifies the best voltage suppression of 330 Volts peak for 6,000 Volts / 3,000 Amps surges. •Mode 1 is Line to Neutral (L-N) suppression. This avoids ground wire contamination and is recommended for interconnected equipment." Adding a sacrificial MOV is superfluous to real series mode surge technology. Furman only added them to make up for the tiny inductor used in their SMP circuit, which makes it a design flaw. 4) Why would I apologize? Furman still lost, and your argument is a red herring. Furman’s SMP is not real Series Mode® surge technology. From your earlier referenced material: "The Problem" "He quickly discovered that the electricity in their facility was unreliable and that the surge suppressor and uninterruptible power supply being used did little to rectify the flaw. He learned that the basis of the protection being used was a metal oxide varistor (MOV), an inexpensive component which will eventually fail in normal service. The MOVs allowed excessive let-through surge energy to the connected equipment, degraded over time, offered poor electronic noise filtration, and shunted surge energy to the ground creating safety ground wire contamination." "The Solution To resolve the problem, he took on the challenge to reinvent the surge suppressor by developing a Series Mode® protection circuit which could safeguard against standard and worst-case electrical anomalies." "It did not incorporate MOVs or sacrificial components of any kind, effectively guaranteeing an unlimited service life without the requirement for testing and/or periodic maintenance. The scientists adopted the Series Mode technology and they quickly discovered it solved their troubles." "Introduction to the AV Industry A friend of the engineer who worked in the AV industry, and an engineer himself, was intrigued by the technology. He knew inconsistent power quality was an issue in the industry and that the current surge suppression technology being used incorporated MOVs that shunted energy to the ground. He also recognized that the act of shunting the surge to ground pollutes the ground with energy that often enters the sound or video system. This was causing equipment disruption, malfunctions, error-codes, reboots, and downtime that degraded performance and increased dealer costs. The Series Mode surge protection technology looked like the perfect solution to alleviate these issues because it overcame all the limitations of MOV shunt-mode devices – it did not have a finite lifetime, its performance did not degrade with time, and it did not pollute the ground." |
sadano, 1) This is from the Ametek website, "To resolve the problem, he took on the challenge to reinvent the surge suppressor by developing a Series Mode® protection circuit " ... do you notice that ® after Series Mode, that is the trademark. That means, if you are Furman, you can’t use Series Mode to brand a product related to surge suppression if you don’t want to get sued. To violate the trade-mark, you just have to use that wording in your marketing materials or branding materials. 2) There are current patents that protect new variations of a series surge protection circuit. The original patents, from the 80s, have long expired. You cannot create new patents to protect old material. Half the circuitry in the Furman is essentially what is in the 80s patent. Anyone can use that technology at this point which was the SurgeX Series Mode protection (you can’t use the trademark nomenclature though). Again, from the Ametek site, "In 2005, SurgeX upped the ante by introducing Advanced Series Mode® (ASM) surge elimination technology. ASM improved on the original technology by incorporating a reactor with two opposing air core inductors to slow surge current down to a trickle. " This is not the technology that Furman is using. 3) SurgeX’s series mode protection is non sacrificial, but it is not perfect. It relies on an inductor as a filter element to block the high speed surge waveform before dumping what is left into a capacitor. As you know, in audiophile circles, adding inductance in front of a power-amp is often frowned upon. It of course also has a limit to how big a surge it can take before the inductor saturates, the diodes blow, or the capacitor is degraded. Adding MOVs in front of this type of surge protector, especially big ones, can significantly increase how big a surge the combined device can handle. Using both, as Furman does, is a feature, not a design fault especially at a given cost point, and the Furman units are competitively priced. 4) I will accept that apology now ... SurgeX Suit Triggers Furman Response By AVNetwork Staff (Systems Contractor News) January 28, 2005 Business
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@atdavid I applaud that you’re actually doing research, but it is half-hearted and incomplete research, and you’re mistaken. Please show me the US Trademark for series mode, or where any of the real series mode surge technology manufacturers use the trademark symbol after series mode. There are two current patents that protect series mode technology. If you bothered to read through my posts here and the linked thread, you would see why you’re wrong. MOVs are sacrificial devices, and the point of series mode surge technology is to be non-sacrificial surge protection. |
sadono, Can you please describe what "real" series mode surge protection is? The picture of the Furman unit here: https://www.furmanpower.com/series-multi-stage-protection-smp on the left (from the large inductor and over) seems to match what is described/drawn in the SurgeX patents I linked to from the 80’s. On the right appears to be some traditional MOVs, and probably some voltage detection to turn on/off the relay on the right side. The additional use of the MOVs is a good thing and probably makes the circuit on the left perform better.
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I just did a little bit of research sadono and I believe you have you facts wrong.
Any protection from those would be long over. I looked on USPTO (patent database) and there are new ones, but they seem to add features or include a transformer in the circuit. |
erik_squires: Right. So the SMP is always on, there’s no activation lag. It also provides relatively low over-voltage protection. These may not be surges, but long lasting events. This can happen if your electric provider doesn’t balance the loads right. This is not true! The part of SMP that is series mode surge technology is always on. However, this section is more limited in its capabilities with let-through voltages, compared to real series mode surge technology. The MOVs and EVS (Extreme Voltage Shutdown), other parts that makeup SMP (Series MULTI-STAGE Protection), have a delay before kicking in. |
First point, DO NOT CLICK erik_squires affiliate links, after he has fed you untrue information! If you are interested in the Furman PST-8 that he promotes, this is the only link to use AFTER clearing your internet browser of cookies: https://www.amazon.com/Furman-Aluminum-8-Outlet-Protection-Conditioning/dp/B000YYVLAK If you don't know what an affiliate link is, or how it profits erik_squires to feed you lies, read the following post: https://forum.audiogon.com/posts/1820850 Secondly, Furman SMP is NOT real series mode surge technology! https://forum.audiogon.com/discussions/furman-smp-is-not-real-series-mode-surge-technology Furman does not license series mode surge technology. They were sued by Zero Surge - the originators and license owner of the series mode technology patent - and lost. Furman was forced to call their technology SMP (Series Multi-Stage Protection), which still uses MOVs. Real series mode surge protection does not use MOVs, because MOVs degrade with surges. This is the whole reason series mode surge technology was invented, to avoid the use of MOVs. |
A whole house surge protector is nothing but a bunch of large MOVs put across the AC lines (and to ground which is also important). This is not a bad thing, this is a good thing. It will have no impact on the sound at all. Schneider/Square-D, Eaton and any number of well known and reputable companies make these. They are relatively inexpensive, but there are larger and smaller ones. If you are in a lightning prone area, go for the big one. It is not going to survive a lightning strike right next to your house, but can survive one in the neighbourhood. The good thing about putting one at the panel, is then you have the inductance of the AC wires from your panel to your equipment to soften the spike. I would like to think that any competent piece of audio equipment, especially really expensive equipment has some level of built in surge protection as well. The combination of the whole house and the in-equipment is likely to get you through most anything. Simple power bars with simple surge protection will put more MOVs across the line. Being at your equipment, that is going to help even more. Some basic power bars add some inductance, which will help more, but that will add impedance to high current draw. Some devices will go even further with larger inductance and circuits after the inductor and provide (in combination with your whole-house protector), protection for just about anything, but it does increase impedance between the AC line and your equipment. You can decide if there is any sonic impact of that or not. |
I have my Gryphon Colosseum running into an AudioQuest Niagara 5000 and I’m happy with how it sounds. I hope it gives my gear some protection from lightning strikes. When I’m home, I still unplug everything when the weather app on my iPhone says there was a lightning strike nearby. Thank goodness for weather radar systems. I had a Tesla Powerwall installed in my mom’s house as a battery backup system. About $8k. She loses power out in the suburbs quite regularly when a power line goes down somewhere. One battery can give two days of power, depending on draw. You can’t put the battery in a living space and it weighs about 500lbs, if I recall correctly. It can go outside. I suppose it would be cool to have it power a stereo and with a couple of batteries and solar, you could live off grid. |
I
recently had an Integrated Amp fail and it occurred to me that it was
the only component in my 2.1 audio system that didn’t have any
surge suppression. I've always kept it plugged directly into the wall
outlet since I experienced slight sound degradation (bass &
dynamics) when plugged into various line filters/surge suppressors.
Wanting better equipment protection, I looked into available
protection methods and decided that a good series-mode surge
suppressor was more than up to the task. After reading numerous
reviews, I decided to give the Zero Surge 8R15W a try. Very nice
people to deal with and their discount for military personnel and
veterans made for an easy decision. |
I tried running my Pass 150.8 into a Bryston BIT 20 power conditioner and got a continuous slight constant hum out of the Bryston so I moved it to a regular Isotek surge supressor and the hum disappeared. The Bryston is essentially (I believe) just a big isolation transformer and Bryston encourages you to plug your power amps and sources both into one. I still power my sources through the Bryston isolation transformer but the Pass goes direct via a surge supressor. |
hi @Donzi Yes, it’s called power factor correction. It’s widely available. Furman is one of the few conditioner vendors I know of who include it in some models since it helps with current delivery a tad. The idea (my memory is rusty) with PF correction is that motors may draw current out of phase with voltage, which may make your meter read more power than you are actually drawing. Install a corrector, and your meter reading will get more accurate, and the bills will drop. You can read more here: https://en.wikipedia.org/wiki/Power_factor There are industrial series mode surge protectors available, but I don’t know of anyone installing them in their homes. All the other tech I know of is shunt/parallel and are inactive until the surge arrives. BTW, for this reason having an excessively good power conduction from your meter to your amp is a bad idea. You are going to be closer to the surge when it hits. A little reactance in the way will blunt it and give the whole house devices time to work. OTOH, that same reactance makes typical MOV based suppressor strips a bad idea, as the voltage during the surge will be greater when they short. For this reason I recommend:
Best, E |
@erik_squires , thanks!! Good to hear from you again. Yes, this comment is giving me "religion." I had mis-appreciated the risks. I have a question, if you might know: A local friend, some time back, sold some company's proprietary device to reduce power bills by smoothing minor fluctuations. The box was sealed, but I always imagined that it was simply a large capacitor, installed into the lines somehow. Supposedly, it was most effective where there were multiple motor-type devices involved. Any idea what type of device might offer such "savings"? And just to ask again what you've already stated, either whole-house, or at-meter, both of these shouldn't diminish sound quality downstream? |
I hooked up the Torus Tot Max today. What a great piece of gear. I had an oh so light buzz which is now gone. The unit is 50lbs and built like a tank. Plenty of space between outlets so all plug sizes work easily. Extremely snug connections. You have to take some effort to push in. I pkayed some Nora Jones and the background seemed a little blacker. No issues with imaging or sound changes. I basically got this unit for protection. I highly suggest Torus |
A lot of good advice here. I absolutely believe that one must, if at all possible, address power coming into the house, and to add surge protection at the panel/sub panel. After many years of reading posts here and other places, about the Environmental Potentials surge/filter line products, and the fact that they adopted their products for residential after having a considerable market base in industrial, medical, and communications, it’s hard to refute the technical measured evidence of wave form correction, reduction of spikes, and other anomalies that the EP products solve and remediate. If they are used in the most sensitive and critical medical, computing, and yes, military, solutions, I decided that their is real value in adding a device to my AC panel to eliminate those same type of “grunge” things affecting my listening experience. I also have dedicated 20 amp lines for the stereo and home theater room, and also use PS Audio P10 for amps, and P5 for all source products. I also added the Rhodium Furtutech outlets and carbon covers. Coincidentally, I have never felt that I needed to purchase Uber expensive power cables because the system sounds great as it with the aforementioned in place. I do have a Shunyata black mamba power cable on the Aesthetix IO Signature phono stage, and regular cables everywhere else. No nasties coming through. My amps are McIntosh MC2301, and I have a compete tube vinyl source feed. I am techie at heart, and always felt measured performance criteria such as THD, IMD, spikes, etc., always affected negatively in some way, the listening experience. If the spikes alone are reduced, that is also preserving our circuits in our most critical and perhaps expensive electronics. Just my two cents. The EP 2050 is the one I am using as it serves as both a surge protector and wave form corrector, it’s an easy solution to add and has enhanced my listening pleasure. |
@eric> series mode it should be obvious SM is not the only and likely not even the primary ‘protector’ tech inside some dual ‘surge and SQ enhancing devices. as such I’m wondering why it is such an obvious note you feel is of dire importance for any one to acquire in such equipment, lest they be at risk? albeit in and of itslef it may well be a barrier or defender for high energy issues, its certainly not the ONLY bit of tech keeping higher energy issues from destroying our gear and consequently it is not a MUST HAVE item in the ‘what ever’ chosen device. sorry,. just saying…. RE Zap Cap for the Sunburn State via Fla Power & light my local energy resource has the same gizmo. its a one off, once hit it is gone approach. naturally replacing it is the duty of the provider and at no cost to the consumer. they afix it to the service pole at the weatherhead or inside the meter box. for the belt and suspenders tact, why not? however, input here says there are better solutions for those who have private domiciles and the dough to invest into these auxilliary choices. additionally, it does nothing for instances wherein lightening comes in on Sattelite or CATV COAX cabling. or for those still enjoying copper line telephones it is no benefit.
I chose not to add one onto my service and opted for as I’ve said, an alternative solution aimed solely at improving SQ…. because it also aided me protection from a few unstable natural weather incidents was purely an Oh, By the Way happy event.. Thankfully.- FWIW another quite intriguing idea I’ve not seen mentioned here is the option of getting off the grid entirely via ‘whole house’ Lithium battery power. this is a trend in new housing developments in Australia, as of course, an option for the prospective owners/buyers of homes in these developments. it is available now in the U.S. as a refit for existing homes. apart from the duty cycle to recharge the batteries, homes exist only off the converted DC. likely there is a full wave bridge rectification going on so the DC emmulates AC, just more precisely as outside issues will not influence such a power resource. BTW… Yikes! these ain’t cheap but prices annually are decreasing. add on solar or wind mills or goats and treadmills, or water wheels, or a whole bunch of trained squirrels on itty bitty treadmills in parallel of course, …and one could end up making money off the local power co. especially if some or much of the install is a DIY project, which is as well offered fully or in part due to its overall modularity. of course the end result here is contained precise steady state voltage when on the batteries, and natural disasters are not being addressed, nor are interior prevailing electrical annomolies, it serves only to serve up cleaner volts and lower third party provider energy consumption., which for some might be inducement enough. |
Hi @donzi ! I think one thing you should consider is hot good your system will sound after a lightning strike. As for the utility service, it’s a shame it isn’t free, especially in Florida, but since it is at your meter and is a shunt, it won’t affect your sound quality. I encourage you to consider having a whole house suppressor installed in your panel. At least that way you won't be buying a subscription. :) In Florida, of all places, I strongly recommend you get a high quality series mode surge suppressor near any gear you want to keep. Best, Erik |
Lowrider, I did quite s bit of research and for the money, the Torus TOT series gets great reviews worldwide. Plus, I got a great recommendation from a dealer so trust. The unit will arrive tomorrow. Besides looking forward to protection, I’m looking forward to declutter the mess J currently have running cables to a strip. I’m going to place the Torus on the middle shelf of my system. |
OK, I only saw a mention of this, this thread raises this question: I'm in Florida where it is pretty dirty. (I've replaced refrigerator circuit boards and the like, because of the surging energy.) I have absolutely no surge protectors on my main equipment to keep the sound level high. But Florida's utility department, FPL, periodically will send me an advertisement for their whole-house surge protection (for some $15/month.) The very concept of this miffs me, as I feel they should be providing this for free, not causing me to buy an add-on. But perhaps that's the nature of a lightning-strike area. My question is, if I went with such an option, do you think this will leave my sound quality untouched? |
Have all my kit plugged into a Niagara 7000 with a Hurricane 20 amp pc to the wall. It has given me peace of mind from power surges - lost a alovely pre amp in the past. The real bonus is the way it has transformed the performance of my Devialet amps. Massively improved detail, bass, faster transients and blacker background. Quite expensive but worth it IMO. |
Surge protectors are better than nothing. They protect mostly against high freqency spikes and line frequencies in the khz range. They kick in about 200v so your class D powet suppy is very susceptible just like a computer. It is essentially a music computer. Isolation transformers with HF filters are very good cleaning up the line UPS units can be good but need to be continuous sign wave type. Much of the big amps will far exceed a UPS ability unless tou shell out big bucks. |
I live in a loft that has 100 other tenants the power is dirty from a lot of appliances. Tried a Niagara 5000 not that much of a difference in the noise floor for the money. Traded it in for a New PS Audio 15 Power Generator Huge Difference. Also you can call them with any questions and in most cases get an immediate response. My Marantz AV newest model 8805 went dead on one side had the dealer contact the company for service 14 days later still no response. ( this is off the topic put has anyone else had these issue with Marantz CS?) |
It's possible that a very close lightning strike will get past anything: http://stormhighway.com/surge_protectors_ups_lightning_protection_myth.php |
I'm using a Wattbox and to be honest I'm still getting some buzzing it maybe that my source line has some kind of feed back loop in it. I've tried so many different amps and RCA/XLR hook ups and all the same BS..lol. From what I have read surge protectors can help with surges but that all depends on how many components are in it. I know PS Audio has some wonderful power conditioners and surge boxes that are really good but they are priced well over my budget. |
I just ordered a Torus TOT MAX. Looks like i'll be good for a while, even if I purchase more powerful amps down the road https://www.toruspower.com/tot-series/ |
I second a prior comment about the more costly Audioquest Niagara power conditioners improving the quality of sound. I own a Niagara 1000, a purchase suggested by our audio dealer, now replaced by the 1200, which is about $1,000. Improvement in sound was quite noticeable. My wife noticed it too. We both play instruments and go to concerts of acoustic music (classical and jazz) and could hear the improvement in clarity. We have a high number of very short-term outages. Our prior APC S20 surge protector, power conditioner with battery back-up did not improve sound, but see below. As to surges, whole house surge protection and devices like the Niagara will not product your equipment from lightning induced power surges. I had my power amp repaired on two separate occasions due to lightning induced damage. The surge came through the cable tv line, into the pre-amp, then the amp. If you live in an area with heavy thunderstorm activity you need to add a surge protector on your cable tv input to your system. The APC S20 and other less costly products typically have sacrificial surge protectors (work once, like a old-fashioned fuse) to protect 75-ohm coaxial inputs from cable tv. |