Lab.gruppen LAB 1600 User Manual

Also see for LAB 1600: Brochure Specifications

Contents

Lab.gruppen LAB 1600 User Manual Manual pdf 7 page image

8. Impedance matching (MLS-switch)The MLS switch is located on the rear panelwith a LED indicator showing then the switch isdepressed and in the 2 ohms position. The MLS (Minimum load select ) switch offer a impedancematching, so you can drive the LAB 1600 in 2ohms without increased heat losses. The chartbelow shows the possible combinations:LAB 1600 MLS switch MLS PositionSpeaker Impedance 4 ohms 2 ohms8 ohms Stereo 430 W 220 W4 ohms Stereo 840 W 430 W2 ohms Stereo 1540 W* 870 W8 ohms Bridged mono 1680 W 870 W4 ohms Bridged mono 3000 W* 1740 WPower rating at 1 kHz and 1% THD* Not recomended selection, thermal protection may occur at high continous power.Table 2.The way to find the best MLSTM position for your application is by experimentation, the amplifier is very wellprotected (even down to 0.3 ohms), but where speed is of essence stick to the fixed positions.Operation modes1. Stereo operationFor stereo (dual channel ) operation, leave the Linkand Phase reverse switches in the undepressedposition. In this mode, both channels operateindependently of each other, with their levelattenuators controlling their respective levels.Never connect either output terminal to groundor in parallel. The recommended minimumnominal impedance, for stereo or tandem operation,is 2 ohms per channel.2. Tandem monoFor tandem ( dual channel-single input) operation ,depress the Link switch. Both channels can now bedriven by a signal, at either input connector. Theoutput connection is the same as in stereo mode.You can use either TRS connectors for linking outetc. Do not use the remaining XLR and TRSconnectors for mixing or other purposes. Bothlevel attenuators are active, allowing you to setdifferent levels for each channel.Never connect either output terminal to groundor in parallel.3. Bridged monoTo bridge the amplifier, depress the Link switch (6)and Phase reverse switch (5). Both channels are thendriven by a single signal at either input. You canuse any remaining input connectors for linking etc.Do not use the remaining XLR and TRS as inputjacks simultaneously for mixing or other purposes.To obtain an output, connect the speaker leads to pin+1 on channel A Speakon to speaker positiveterminal and pin +1 on channel B Speakon tospeaker negative terminal . Do not connect eitherof the -1 (negative) pins of the Speakons. Do notconnect speakers to channel A or B in the normalmanner in bridge mode, as this can cause seriousdamage.The recommended minimum nominal impedancefor bridged mono is 4 ohms (equivalent to drivingboth channels at 2 ohms).Driving bridged loads of less than 4 ohms may causea thermal overload.Figure 10. Bridge mono connectionBoth level attenuators must be at the same position.We recommend you to put them in the 0 dB (full)position.7