Mackie SR408 / SR568 Owner's Manual - Page 71

TRS Acronym for Tip-Ring-Sleeve, a scheme for connecting three conductors through a single plug or jack. 1⁄4" phone plugs and jacks and 1⁄8" mini phone plugs and jacks are commonly wired TRS. Since the plug or jack can carry two signals and a common ground, TRS connectors are often referred to as stereo or balanced plugs or jacks. Another common TRS application is for insert jacks, used for inserting an external processor into the signal path. In Mackie mixers, the tip is send, ring is return, and sleeve is ground. TS Acronym for Tip-Sleeve, a scheme for connecting two conductors through a single plug or jack. 1⁄4" phone plugs and jacks and 1⁄8" mini phone plugs and jacks are commonly wired TS. Sometimes called mono or unbalanced plugs or jacks. A 1⁄4" TS phone plug or jack is also called a standard phone plug or jack. unbalanced An electrical circuit in which the two legs of the circuit are not balanced with respect to ground. Usually, one leg will be held at ground potential. Unbalanced circuit connections require only two conductors (signal "hot" and ground). Unbalanced audio circuitry is less expensive to build but under certain circumstances is more susceptible to noise pickup. unity gain A circuit or system that has its voltage gain adjusted to be one, or unity. A signal will leave a unity gain circuit at the same level at which it entered. In Mackie mixers, unity gain is achieved by setting all variable controls to the marked "U" setting. Mackie mixers are optimized for best headroom and noise figures at unity gain. VLZ Acronym for very low impedance. (Impedance is measured in ohms represented by the Ω symbol, which is the last letter of the Greek alphabet. This is how the letter Z is used instead of I.) VLZ is one of the most important reasons why inherent noise levels on Mackie mixing boards are so minuscule. Thermal noise is something that's created by all circuitry and usually transistors and resistors are the worst culprits. The basic rule with thermal noise is: the higher the impedance, the more the noise. Mackie's VLZ design reduces thermal noise by making internal impedances as low as possible in as many places as possible within the console. VLZ is achieved by scaling down resistor values by a factor of three or four - resulting in a corresponding reduction in thermal noise. This is especially true for the console's mixing buses. volume Electrical or sound level in an audio system. Perhaps the only thing that some bands have too much of. VRMS See RMS. wet With added reverberation or other effect like echo, delay or chorusing. XLR connector See Cannon. 71