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07/04/2015 Linn Active Cards
Firstly the basics, the Linn active card is designed to take the full range audio signal provided by the pre-amplifier, filter it and then only output a portion of the speaker of particular frequency range as required for a single speaker drive unit in a particular Linn speaker. That is, a set of cards are designed specifically for a particualr Linn speaker. The active cards are normally fitted inside Linn power amplifiers although the orignal active cards could be fitted in a standalone powered Linn box (called an 'Active Box') and then used with power amplifers from any manufacturer. The key practical difference between the three versions of the active cards is that each would only fit certain Linn amplifiers of the same generation.
The original active cards were mono, that is each card filtered a particular frequency range for one channel only. So for a three way Linn speaker you would need six mono active cards and six channels of power amplification. The latter normally achieved by using three stereo power amplifers. The amps of the era of these cards were primarily the LK100 and the Klout. However they also fitted the 5105 and the LK240 mono amplifer. The LK100 required a bracket to hold the cards inside the amplifer. The cards could also be fitted to the original Linn Majik-i integrated amp although this also need a different bracket, called a Sneaky Active plate which are now very very rare although the LK100 brackets are quite common.
The next generation of active cards were stereo. That is they had separate fitlers for the same frequency band for each channel on one card. So for the three way Linn speaker you would need three stereo active cards. These cards fitted later Linn amplifiers - the LK140 and LK85 being the most common. Alhough two stereo cards could be fitted in a Linn 5125 five channel stereo amplifer using four of its power amplifer channels. The cards also fitted the Linn 2250 amplifer.
There is no official method of using the mono cards in amps designed for the stereo cards or vice-versa.
The last and current generation are called the Chakra mono active cards. They are desinged to fit in the current range of Linn Majik and Akurate amplifiers although the will also fit the earlier Chakra amplifiers (which were simply renamed Akurate and Majik for the x200 and x100 ranges respectively) Alhough mono cards again they will not directly fit in the amps designed to work with the original mono cards. However, Linn have made available 'adaptors' for both the original 'mono card' amplifiers and the later 'stereo card' amplifiers. These cards are FREE if bought with a new set of Linn Chakra active cards but if bought alone they cost the same as the Chakra active cards themselves!!
We hope this provides the basics on the Linn active cards and the different tyoes but if you would like to know more or have questions then please do e-mail us - firstname.lastname@example.org