Linn Aktiv for 5120

2 x Treble cards
1 x Bass card

From Linn owners manual:
The Linn AKTIV Crossover modules enable filtering between amplifiers and loudspeakers. The active filters give greater accuracy and lower distortion than conventional passive crossovers. The power amplifier is connected directly to the drive units so that none of the amplifier's power is lost. The drive units are more controlled, give lower distortion and higher efficiency. A good active system gives a sound which cannot be achieved by any other means. You just have to listen to it. A crossover is a filter which splits the complete music signal into two or more frequency bands before it is fed to the drive units in the loudspeakers. This is done because no single drive unit can operate over the entire musical range. With a passive crossover, this filtering is done after the power amplifier, so only one power amplifier is required. With an active crossover, the filtering is done before the power-amplifier, so it becomes possible to dedicate a power amplifier to each drive unit. This is ideal for both the amplifier and the drive unit.

Active crossover modules optimised for use with Linn KELTIK, KABER, KEILIDH, TUKAN, SEKRIT, 5140 and 5120 active loudspeakers. (KABER, KEILIDH, TUKAN, SEKRIT, 5140 and 5120 are converted internally from passive to active by your Linn retailer)

Input impedance:
KELTIK system input impedance             10k     ohm
KABER system input impedance             25k     ohm
KEILIDH system input impedance             33k     ohm    
SEKRIT system input impedance             5k     ohm
TUKAN system input impedance             5k     ohm
5140 system input impedance             25k     ohm
5140 in 5105 system input impedance         16k    ohm
5140 in KLOUT system input impedance         33k     ohm
5120 system input impedance             5k     ohm
5120 in 5105 system input impedance         2.35k    ohm
Input sensitivity                     1v rms
Hum and Noise when used in LK100 and KLOUT     -90dbv

Adjustment range: (per module)      Treble         +/- 2dB in 0.5dB steps (approx)
                    Bass         +/- 4dB in 1dB steps (approx)
                    Keltik      -3db at 20, 30, 40 or 50Hz (approx)