User manual JBL L75

[. . . ] Bi-wiringcanprovideseveral and sonicadvantages considerably more flexibilityin power amplifier selection. Reduction of intermodulation The majorityof current flowing is betweenan amplifierandspeaker of devotedto the reproduction or bass. fn frLæ"60% more of an for amp'spower is destined the woofers. When current flows a through a wire, it produces which fìeld (EMF) magnetic at and expands collapses a rate top DrawingL-A - L755 position view g' side-mounted woofers face inward 3' front view DrawingL-B- L755 position Drawing L-C - One-Amp Bi-Wire equalto that of the music's complex frequency components. lf a single speaker wire mustconductthe full musical frequency spectrum, preponderance this of low frequency informationcan interactwith or modulote hþh frequencies. [. . . ] resulting The intermodulotion createaudible can changes treble evenbeforeit to reaches your loudspeakers. By using separate conductors for highand low frequencies (drawingL-C), unwantedtreble modulationis avoided. Bass flows through one, treble throughanothen Frequency-optimized cables Having opportunityto use the separate and LF cables, HF allows you to employconductorsbest suitedto eachfrequencyrange. As previously noted, most amplifìer power ís destined your L755's for woofers, so upon first consideration, would makesense use ¡t to veq/ thick wire for LFconnections andtjrinnerwire for HF connections. Howeve[the very fact that treble is hþher in frequency, means it is actually more sensitive the to type andgauge wire used. Hþh of frequencies prone to are from a phenomenon attenuation calledskr:n effedt. High quality speaker interconnect wires minimize skineffectby employing a largenumberof thin conductors with very low oxygencontent2. Optimall¡youshoulduseaudiofor phileinterconnects both HF and LFconductors. Howevenif use ydirr budgetintervenes, the for cables the bestqualityspeaker connections and highfrequency cables laæn planto add better bass Amplifier flexibility Bi-wiringalsoallowsyou the stereo option of usingseparute for power amplifiers left and rþht or L755 loudspeakers evenfour mono power amplifiers. ' Usingtwo stereoamplifiers (drawingL-D) cannot only add but sonicimprovements upgrade as convenience well. ln facLsincethe crossOperatingtwo amplifier over point for the L755'sHF/LF channels with the L755 strapping connections l50H¿ using is amplibarsin placecanseriously fìersof the samepower for both damage amplifìers!lf your preamplifier just one has trebleconnections recomis set of stereo outputs, you will mended. For example, a in 2-amplifier bi-wire hook-up, if you are usinga 200-wattBrandX amp tns c not to oy ú, "ttfrey cant There aresome *perb ulbe amplifiers whió prwirle wery bit as for the leftLT, usea matching 200- mudr tþtnr-*as solidslãte des¡gnsHowwer, watt Br¿ndX ampfor the rþht L755. úey are highpower modeb andare very, VERY epersive Moderåtly"riced obe porveramplifurs poweringthe left L755 Or if you'r:e tend to be nndenæly powered aswdL They midn low frequencyconnection with a be accepable forpowerír6de mldbesfmËrarrgd 1SO-watt BrandYampandthe high reble poni<rnof tÍ-wired L755s, hft\ rc'rildnor, in o. ¡r oFinitxr be úæ bestdrcicefor lo¡¿bass frequencies with a 1S0-watt Brand reproduaÍcn in abi-wired sFternwhidt willb Drawing L-H - Four-Amp Hook-Up Detail $þ æ realt*ícconcert tnll leveh 3 needto use"Y' cords in the three-ampand four-ampbLwire hook-ups. "Y'cords are from manysources available yourJBLdealer. i¡cluding lf i, oú hävehookedup your L755's in. anyof the bi-wire confìgurait tioÀs indicated, is not to advisable useadditional or either separately speakers, simultaneously. oneAs with conventional connections shown in amplifier make tlre main L Seriesmanual, cables are surethat all speaker the samelength. Bi-amplification Another adrancedoperation alternativeis bktmplifuaion. Insteadof beingdivided by an internal crossovec full frequency the spectrum is fikered into two segmentsby a2-way octernal which is conelecuoniccrossoYen the preamplifier nected between and power amplifiers. mode, the LZs In bi-amplified woofer and midrangdhightransducers are frequency connected direrlly@ separate amplifiers. [. . . ] mode, the LZs In bi-amplified woofer and midrangdhightransducers are frequency connected direrlly@ separate amplifiers. Only a portion of the LZs internal dividingnetwork is used. The transducer woofer and mid-bæs are sectionofthe crossover bymodification passed a special via which canbe performedby your JBLdealer. Do not attemptto b¡amplifryour L755'swithout having yourJBLdealerdo the proper elect¡onic A modification. suÍtable rdt¡st cnossover beused. [. . . ]