Important criteria to consider when comparing listening devices:<\/em><\/strong><\/p>\n<\/div>\n Sensitivity<\/strong> – how well the device amplifies sounds from the transmitting material\u00a0<\/em><\/p>\n<\/div>\n Frequency Range<\/strong> – how broadly the device can hear all the sounds created by a leak<\/em><\/p>\n<\/div>\n Filtering<\/strong> – how effectively the device can filter out background noise enabling \u00a0you to focus on a leak sound<\/em><\/p>\n<\/div>\n The standard ground microphones that come with\u00a0Fisher’s XLT17\u00a0<\/a>and the\u00a0XLT30H<\/a>\u00a0listening devices,\u00a0use piezoelectric microphones<\/a> because these are known to be the best type of microphone to use in situations where sounds are being picked up from liquids or solids.\u00a0 Virtually every company that makes serious equipment for locating underground plumbing leaks for municipal work incorporates piezoelectric technology. Accessing the technological knowledge of those who have experience in this area is one reason we have chosen to work with Fisher and utilize their products.\u00a0 This type of equipment requires more specialized expertise than standard microphone amplification (that used for music\/voice etc.).<\/p>\n<\/div>\n In practice you will find that sensitivity by itself however is not the only important performance criteria.\u00a0 Most any device will be able to amplify a sound to the point that it will hurt your ears.\u00a0 What’s more important is hearing the right sound and distinguishing it from background noise.\u00a0 That’s where the other two important criteria come into play.<\/p>\n<\/div>\n <\/p>\n Both pressurized underground plumbing leaks and static shell leaks in the pool make noises in a wide range of frequencies depending on a variety of conditions. \u00a0\u00a0We like to think of the sounds a leak makes in the same way we do instruments in an orchestra.\u00a0 You want to be able to hear everything from the shrillest piccolo to the deepest tuba.\u00a0 Although every leak is different, as general rule underground plumbing leaks make sounds in the lower frequency ranges while static leaks in the shell of the pool are in the higher range.\u00a0 If your listening device doesn’t pick up sounds at the top or bottom of this range you will be missing the fullness of the sound a leak makes or you may miss it altogether.\u00a0 Both the Fisher XLT17 and XLT30H pick up sounds in a frequency range of 20Hz to 6000Hz.\u00a0\u00a0In addition, the XLT30H includes a switch that enables the unit to work effectively both when sounds are in the low range (for underground leaks picked up by the Bigfoot microphone) and the higher ranges (for underwater leaks picked up by the hydrophone).<\/p>\n<\/div>\n <\/p>\n The final performance criteria, and what we consider to be the most important for swimming pool applications, is an area where Fisher devices particularly shine over all others we have researched.\u00a0 A listening devices filter allows you to specifically highlight (or eliminate) a specific range of sounds.\u00a0 Consider for instance that we only wanted to hear the violins in the orchestra of leak sounds we imagined above.\u00a0 Filtering is important because the devices are so sensitive that we will likely hear other sounds around the pool (it always seems as though the next door neighbor want to mow their grass when you’re trying to find a leak!).\u00a0 The filter helps us zero in on the leak sound without being distracted by the background noise.\u00a0 Additionally, different ranges of sound behave differently underground or underwater.\u00a0 Low frequency sounds travel much further than high frequency sounds.\u00a0 By selecting high frequency sounds once a leak sound has been identified the frequency filter can help in pinpointing leaks to a small area.<\/p>\n<\/div>\n <\/p>\n Fisher devices provide a wide range of filtering options to address most any scenario. The\u00a0Band Pass<\/i>\u00a0filter<\/strong> allows selection of a narrow band of frequency anywhere in the range of sound.\u00a0 The\u00a0Hi Pass<\/i>\u00a0filter <\/strong>focuses high frequency sounds providing adjustment of the low end of this range.\u00a0 The\u00a0Low Pass<\/i>\u00a0filter<\/strong> does the opposite – focusing on the low end and providing an adjustable high end..\u00a0 The XLT30H also includes a\u00a0Notch Filter<\/i><\/strong>\u00a0that allows the elimination of a specific frequency range (for instance to minimize the “hum” of a nearby air-conditioner) and can be used at the same time as the other filters.<\/p>\n<\/div>\n <\/p>\n Another noise minimizing feature available on Fisher devices is especially important when the unit is used for listening to pipes in the ground.\u00a0 The Bigfoot muffler utilized by Fisher to minimize outside noises transmitted through the air is the best we’ve seen.\u00a0 This rubber boot deadens outside noises preventing them from reaching the sensitive piezoelectric microphone which makes direct contact with the pool deck or ground through a heavy aluminum foot.<\/p>\n<\/div>\n <\/p>\n Ultimately, we are convinced, that Fisher Listening Devices as sold by Anderson Manufacturing Co. are the most technologically advanced, well rounded tool for all types of swimming pool acoustical leak location<\/strong> \u00a0\u00a0They have been continually improved through the years and currently represent the best package for addressing pool leak problems in both the plumbing and shell.\u00a0 We back our belief with the evidence of thousands of successful customers and a satisfaction guarantee that promises your money back if you are not satisfied with their performance.<\/p>\n<\/div>\n If you have made it this far through this you have taken in a lot of information, hopefully it has been helpful in making decisions that will affect your leak detection success.\u00a0 Remember you can always call and talk through the buying process or for technical help regarding a leak or leak detection equipment. Thanks for reading!<\/p>\n<\/div>\n <\/p>\n","protected":false},"excerpt":{"rendered":" When it comes those tough underground plumbing leaks,\u00a0electronic listening devices are the backbone of the leak detection industry. \u00a0 While there are\u00a0other methods the most reliable and consistent method is to make a noise at the leak with pressurized air escaping into water saturated soil, then listen for where the noise is coming from.\u00a0 This […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[44,52],"_links":{"self":[{"href":"https:\/\/www.leaktools.com\/blog\/wp-json\/wp\/v2\/posts\/128"}],"collection":[{"href":"https:\/\/www.leaktools.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.leaktools.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.leaktools.com\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.leaktools.com\/blog\/wp-json\/wp\/v2\/comments?post=128"}],"version-history":[{"count":17,"href":"https:\/\/www.leaktools.com\/blog\/wp-json\/wp\/v2\/posts\/128\/revisions"}],"predecessor-version":[{"id":1190,"href":"https:\/\/www.leaktools.com\/blog\/wp-json\/wp\/v2\/posts\/128\/revisions\/1190"}],"wp:attachment":[{"href":"https:\/\/www.leaktools.com\/blog\/wp-json\/wp\/v2\/media?parent=128"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.leaktools.com\/blog\/wp-json\/wp\/v2\/categories?post=128"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.leaktools.com\/blog\/wp-json\/wp\/v2\/tags?post=128"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}![\"The](\"https:\/\/www.leaktools.com\/blog\/wp-content\/uploads\/2017\/01\/LANCEWITHFISCHERBELLMIC.jpg\")
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