Linn isobarik aktiv crossover owners manual

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2NTRODUCTION Thank you for buying the Linn AKTIV Crossover. The AKTIV isthe culmination of many years of research by Linn. It has long been recognised that active crossover systems can improve loudspeaker performance. This is the first electronic crossover to realise the full potential of an active loudspeaker system. Active and Passive:With a conventional passive crossover the signal from the amplifier isdivided into frequency bands (bass, mid and treble) by a passive circuit located within the speaker cabinet. It is not mains powered, hence the description 'passive". By contrast, an active system separates the sound into separate bass, mid-range and high frequency signals before amplification. Then, three amplifiers, not one, send these signals directly to the speaker's respective drive units. The advantages are better control of the drive units and more precise separation of the audio frequencies. An active crossover allows a degree of control of the signals and the drive units to a precision not practical or possible in a passive crossover. For example, the response of a passive crossover is affected by the impedance of the drive unit to which it is connected, however the impedance of a drive unit varies widely with frequency and drive level. In an active crossover, because the drive units are driven from individual power amplifiers, any change in their input impedances cannot affect the crossover responses at all. The AKTIV also includes compensation for the amplitude, phase and time responses of the Isobarik, and has been designed and manufactured with precision for the highest level of performance.I

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3OPERATION It is recommended that the crossover is turned on first, followed by the power amplifiers individually. The crossover will perform best after about half an hour of warm-up. It will run slightly warm to the touch. The running temperature is independent of programme material or level. As with all electronic equipment do not expose the AKTIV to strong direct, or radiated, heat.GENERAL INFORMATION & MAINTENANCE The crossover can be left switched on continuously if required. Its power consumption is very low. We recommend that you switch off the power amplifiers when not in use. The case of the AKTIV can be wiped with a damp cloth to remove dust and finger marks. The only maintenance suggested is occasionally to unplug then re-connect all the connectors. This wiping action cleans the contacts.FAULT FINDING The most likely time for faults or errors to occur is during installation and these will normally be rectified by the dealer. Faults can be isolated by determining which channel (left or right) and which frequency band is wrong. Remember that the LK2 power amplifiers have a protection trip, which will shut down an overloaded channel. To reset the amplifier, switch the power off for five minutes. If a power indicator light is not visible on the AKTIV check: the mains cable is plugged into the back securely, the mains fuse in the plug (if fitted) and the mains fuse in the power inlet on the back of the AKTIV are intact. To check the mains fuse in the power inlet remove the power cord then using a small flat blade screwdriver flick the fuse holder drawer out of the power inlet unit. Check the fuse. If it is blown, replace it with an identical one. The importance of double checking all signal and speaker connections before switching on cannot be over emphasised.