{"id":1288,"date":"2016-08-05T15:47:25","date_gmt":"2016-08-05T20:47:25","guid":{"rendered":"http:\/\/android-originals.com\/tulsasound\/?page_id=1288"},"modified":"2016-08-06T17:18:10","modified_gmt":"2016-08-06T22:18:10","slug":"general-equations-for-combinations-of-humbucking-pairs","status":"publish","type":"page","link":"http:\/\/android-originals.com\/tulsasound\/tutorials\/humbucking-pairs\/general-equations-for-combinations-of-humbucking-pairs\/","title":{"rendered":"General Equations for Combinations of Humbucking Pairs"},"content":{"rendered":"<p>\u00a9 2016 Don Baker dba android originals, TulsaSoundGuitars.com, HumbuckingPairs.com<\/p>\n<h2>Mathematical Definitions<\/h2>\n<p>First we need some definitions of mathematical terms to bring everyone onto the same page.<\/p>\n<p><strong>Factorial n<\/strong>: the product of all numbers from n down to 1<\/p>\n<p>Math 1:\u00a0\u00a0\u00a0\u00a0\u00a0 n! = n*(n-1)*(n-2)* \u2026 2*1,\u00a0 i.e.,\u00a0 4! = 4*3*2*1 = 24<\/p>\n<p><strong>Summation series<\/strong>: the sum of a set of expressions with the same formula, differing according to the incremental change (usually an integer change) of one or more terms.\u00a0 Such as, the summation of n! from 1 to 4, by increments of 1:<\/p>\n<p>Math 2:\u00a0 <a href=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath02.png\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-1290\" src=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath02.png\" alt=\"BEMath02\" width=\"377\" height=\"60\" srcset=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath02.png 377w, http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath02-300x48.png 300w\" sizes=\"(max-width: 377px) 100vw, 377px\" \/><\/a><\/p>\n<p><strong>Product series<\/strong>: the product of a series of expressions, which change according an increment of one of the terms, such as the product of i as i decreases from n to 1:<\/p>\n<p>Math 3:\u00a0 <a href=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath03.png\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-1291\" src=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath03.png\" alt=\"BEMath03\" width=\"113\" height=\"47\" \/><\/a><\/p>\n<p><strong>Permutations<\/strong>: the number of <em>unique<\/em> ways to separate k things out of n things, if the order of which thing comes first matters:<\/p>\n<p>Math 4:\u00a0 <a href=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath04.png\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-1292\" src=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath04.png\" alt=\"BEMath04\" width=\"209\" height=\"61\" \/><\/a><\/p>\n<p>For example, the number of ways can 8 Olympians be awarded gold, silver and bronze is 8!\/5! = 40320\/120 = 336.\u00a0 Note the two notations (of several) shown above for permutations.\u00a0 We are not really going to use permutations, but it helps to understand combinations.<\/p>\n<p><strong>Conbinations<\/strong>: the number of <em>unique<\/em> ways n things can be taken k at a time without regard to order:<\/p>\n<p>Math 5:\u00a0 <a href=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath05.png\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-1293\" src=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath05.png\" alt=\"BEMath05\" width=\"353\" height=\"62\" srcset=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath05.png 353w, http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath05-300x53.png 300w\" sizes=\"(max-width: 353px) 100vw, 353px\" \/><\/a><\/p>\n<p>For example, the number of ways that 8 Olympians can stand on the podium, regardless of who wins what is 336\/3! = 56.\u00a0 Another way to think of it is to put 3 factors in the top and bottom of a fraction:<\/p>\n<p>Math 6:\u00a0 <a href=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath06.png\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-1294\" src=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath06.png\" alt=\"BEMath06\" width=\"221\" height=\"64\" \/><\/a><\/p>\n<h2>Unique combinations of KK dual-coil humbucking pickups taken MM at a time, N<sub>KK,MM<\/sub><\/h2>\n<p>Combinations of pickups don\u2019t tell you how to connect them together.\u00a0 They only tell you how many you have to work with.\u00a0 In this case, the formula is simple:<\/p>\n<p>Math 7:\u00a0 <a href=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath07.png\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-1295\" src=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath07.png\" alt=\"BEMath07\" width=\"305\" height=\"64\" srcset=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath07.png 305w, http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath07-300x63.png 300w\" sizes=\"(max-width: 305px) 100vw, 305px\" \/><\/a><\/p>\n<p>For example, if you have 3 humbuckers, and you want to know how many pairs of humbuckers (the equivalent of a humbucking quad of matched single-coil pickups) you can make out of them, the answer is:<\/p>\n<p>Math 8:\u00a0 <a href=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath08.png\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-1296\" src=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath08.png\" alt=\"BEMath08\" width=\"197\" height=\"64\" \/><\/a><\/p>\n<p>The total number of all possible different unique combinations, from MM = 1 to KK is:<\/p>\n<p>Math 9:\u00a0 <a href=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath09.png\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-1297\" src=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath09.png\" alt=\"BEMath09\" width=\"329\" height=\"65\" srcset=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath09.png 329w, http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath09-300x59.png 300w\" sizes=\"(max-width: 329px) 100vw, 329px\" \/><\/a><\/p>\n<p>In other words, for 3 humbuckers, the number of single, pairs and triples (equivalent to pairs, quads, and hexes of matched single-coil pickups) is:<\/p>\n<p>Math 10:\u00a0 <a href=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath10.png\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-1298\" src=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath10.png\" alt=\"BEMath10\" width=\"533\" height=\"69\" srcset=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath10.png 533w, http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath10-300x39.png 300w\" sizes=\"(max-width: 533px) 100vw, 533px\" \/><\/a><\/p>\n<p>Table 1 shows how the number of combinations fall out for 1 to 6 dual-coil humbuckers.\u00a0 Note that the columns in the table are binomial coefficients, and the bottom row follows a progression, 1, 1+2, 3+4, 7+8, 15+16, 31+32.\u00a0 So the table could be extended indefinitely in that manner.<\/p>\n<p><a href=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BETable01.png\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-1301\" src=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BETable01.png\" alt=\"BETable01\" width=\"438\" height=\"319\" srcset=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BETable01.png 438w, http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BETable01-300x218.png 300w\" sizes=\"(max-width: 438px) 100vw, 438px\" \/><\/a><\/p>\n<p>Although the number of PAF-sized humbuckers that can fit between the neck and bridge of a guitar is probably no more than 4, a piano would have a lot more room.<\/p>\n<p><strong><em><br \/>\n<\/em><\/strong><\/p>\n<h2>Unique combinations of K match single-coil pickups taken M pairs at a time, SN<sub>K,M<\/sub><\/h2>\n<p>This is a bit more tricky.\u00a0 At the humbucking pair level, dual-coil humbuckers are already fixed.\u00a0 If you have humbuckers AB, CD &amp; EF, for the inner coils A, B, C, D, E &amp; F, coil A is always connected to coil B.\u00a0 But for the matched single-coil pickups, A, B, C, D, E &amp; F, any coil can associate with any other coil.<\/p>\n<p>For the coil set A &amp; B, we have a single pair, AB, or the number of the combination of 2 things taken 2 at a time.\u00a0 For the coil set A, B &amp; C, we have the pairs AB, AC &amp; BC, or the number C(3,2) = 3.\u00a0 For the coil set A, B, C &amp; D, we have the pairs, AB, AC, AD, BC, BD, and CD, or the number C(4,2) = 6.\u00a0 We also have the unique quad sets, (AB,CD), (AC,BD) &amp; (AD, BC), the number of 3.\u00a0 This is obiously not the same as 6 pairs taken 2 at a time, C(6,2) = 15.\u00a0 It can\u2019t be because if we had a combination like (AB,AC), it would not be a quad, and there is no way it could be humbucking.<\/p>\n<p>So what happens if we add a 5<sup>th<\/sup> coil, E?\u00a0 First, all the combinations from the first four still exist.\u00a0 To those we add the combinations derived from adding E.\u00a0 E can combine uniquely with each of the original 4 pickups for form K-1 pairs additional pairs, for a total of 10.\u00a0 To form quads, the remaining 3 pickups can be taken 2 at a time to form the second pair, for a total of 3. So E adds 4*3 = 12 humbucking quads for a total of 15.<\/p>\n<p>If we add a 6<sup>th<\/sup> coil, F, We have not only more pairs and quads, but a humbucking hex, (AB, CD, EF).\u00a0 If we add a 7<sup>th<\/sup> coil, G, we have more pairs, quads, and hexes.\u00a0 If we add an 8<sup>th<\/sup> coil, H, we have more pairs, quads, hexes, and a humbucking oct.<\/p>\n<p>Without going through the entire development, the equation that results for the number, SN<sub>K,M<\/sub>, of unique combinations of K matched single-coil pickups organized as M humbucking pairs is:<\/p>\n<p>Math 11:\u00a0 <a href=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath11-b.png\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-1314\" src=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath11-b.png\" alt=\"BEMath11-b\" width=\"462\" height=\"217\" srcset=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath11-b.png 462w, http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath11-b-300x141.png 300w\" sizes=\"(max-width: 462px) 100vw, 462px\" \/><\/a><\/p>\n<p>Note that in the last form, (j-2M)! need not be calculated, but simply removed from the sequence of the product (j-1)!.<\/p>\n<p>As before with dual-coil humbuckers, the pairs, quads, etc., for a given K can be added together to get the total number of humbucking combinations of matched single-coil pickups, TSN<sub>K<\/sub>.<\/p>\n<p>Math 12:\u00a0 <a href=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath12.png\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-1300\" src=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BEMath12.png\" alt=\"BEMath12\" width=\"162\" height=\"61\" \/><\/a><\/p>\n<p><a href=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BETable02.png\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-1302\" src=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BETable02.png\" alt=\"BETable02\" width=\"537\" height=\"296\" srcset=\"http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BETable02.png 537w, http:\/\/android-originals.com\/tulsasound\/wp-content\/uploads\/2016\/08\/BETable02-300x165.png 300w\" sizes=\"(max-width: 537px) 100vw, 537px\" \/><\/a><\/p>\n<p>&nbsp;<\/p>\n<p>Again, this does not tell us how to connect the pickups together, only how many humbucking pairs, quad, hexes, octs, etc., of electromagnetic pickups there are to work with.<\/p>\n<p>Published Aug 5, 2016.\u00a0 <strong>Correction<\/strong>: Table 2 was calculated in a spreadsheet, and indicated errors in the <a href=\"http:\/\/android-originals.com\/tulsasound\/tutorials\/humbucking-pairs\/provisional-patent-application-filed-for-humbucking-quads\/\">previously posted page<\/a> in HumbuckingPairs.com.\u00a0 Those have been corrected.<\/p>\n<p><strong>Aug 6, 2016 Note<\/strong>: It&#8217;s possible for this math to contain errors.\u00a0 Math 11 has been reworked.\u00a0 If you find any, please let me know, mailto:\u00a0 axe1 [a] TulsaSoundGuitars [d] c*m\u00a0 No solicitations for web site development or mobile apps, please.\u00a0 I do my own work.<\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u00a9 2016 Don Baker dba android originals, TulsaSoundGuitars.com, HumbuckingPairs.com Mathematical Definitions First we need some definitions of mathematical terms to bring everyone onto the same page. Factorial n: the product of all numbers from n down to 1 Math 1:\u00a0\u00a0\u00a0\u00a0\u00a0 &hellip; <a href=\"http:\/\/android-originals.com\/tulsasound\/tutorials\/humbucking-pairs\/general-equations-for-combinations-of-humbucking-pairs\/\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":1179,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":[],"_links":{"self":[{"href":"http:\/\/android-originals.com\/tulsasound\/wp-json\/wp\/v2\/pages\/1288"}],"collection":[{"href":"http:\/\/android-originals.com\/tulsasound\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"http:\/\/android-originals.com\/tulsasound\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"http:\/\/android-originals.com\/tulsasound\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/android-originals.com\/tulsasound\/wp-json\/wp\/v2\/comments?post=1288"}],"version-history":[{"count":5,"href":"http:\/\/android-originals.com\/tulsasound\/wp-json\/wp\/v2\/pages\/1288\/revisions"}],"predecessor-version":[{"id":1315,"href":"http:\/\/android-originals.com\/tulsasound\/wp-json\/wp\/v2\/pages\/1288\/revisions\/1315"}],"up":[{"embeddable":true,"href":"http:\/\/android-originals.com\/tulsasound\/wp-json\/wp\/v2\/pages\/1179"}],"wp:attachment":[{"href":"http:\/\/android-originals.com\/tulsasound\/wp-json\/wp\/v2\/media?parent=1288"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}