2 off (one pair) 15.25kHz anti-aliasing audio filter modules for Lexicon PCM70
Replacements for Murata AFL89WB15250
(Other frequencies also available for other units - see below)

The Lexicon PCM70 effect processors used Murata AFL89 filter modules (one for each input and output) to maintain their superb audio performance. These were very high-performance parts, semi-custom made and, as a result, now virtually unobtainable as spares.

Unfortunately, with age these modules have become unreliable. Some simply stop working, while others fail in a particularly unpleasant way. Their circuitry is encapsulated within a metal can, and eventually the encapsulating resin starts to liquify and ooze a black, tar-like substance across the circuit board. The leakage can degrade other components and is very onerous to remove.

At Benden Sound Technology we have observed this failure in multiple units. Interestingly, it tends to affect most or all of the filter modules in a given unit, not just the odd example. The exact failure mechanism is unknown - perhaps it is temperature-related, or simply slow chemical breakdown of the material. Very late examples of the Murata parts did away with the can and made do with a hard lacquer coating, so perhaps they knew that there was a problem even then.

Failure of filters usually makes itself known through dead channels, excessive noise and distortion at the output, or even audible high-frequency whining. It is often only then that the lid is removed and leakage observed from the filters.

Until now, no adequate replacement has been available for these filter modules. Very infrequently a single unit might become available on eBay at a high price, but to future-proof an entire unit requires multiple devices. Various DIY solutions have been proposed but, truth be told, the Murata filters achieve remarkable performance in a very small space and it has always proved difficult to match.

We finally decided to rise to the challenge when both a Lexicon 480L and a Lexicon 200 arrived simultaneously with full sets of leaking filter modules. It took several iterations to perfect, but we are now proud to be able to offer replacement modules that are a drop-in replacement both physically and electronically to the Murata AFL89 and offer identical performance.

This listing is for a TWO modules with a cutoff frequency of 15.25kHz (15,250Hz, hence the 15250 suffix in the Murata part number).

Not-so Small Print

Replacement of filter modules requires disassembly of the PCM70 and high-level soldering and desoldering skills, so should not be undertaken lightly. If in doubt, please delegate the work to a qualified technician since we can accept no responsibility for damage done during installation.

Murata Filters in Other Units

Similar filter modules are used in other equipment. At least three different cutoff frequencies exist, and filters with the correct cutoff frequency MUST be used. Known examples are:

Equipment using AFL89 filters with a 20kHz cutoff frequency (AFL89WB20000):

Lexicon 480L (x6)
Eventide H3000 (x4)

Equipment using AFL89 filters with a 15.25kHz cutoff frequency (AFL89WB15250):

Lexicon PCM70 (x3)

Equipment using AFL89 filters with a 10/10.5kHz cutoff frequency (AFL89WB10000/10500):

Lexicon PCM60 (x3)
Lexicon 200 (x4 - actually uses AFL811 modules but can be modified)

We stock 20kHz filters as standard; other frequencies are manufactured to special order since the numbers involved are so small. Please check our other listings for current stock availablity. If you have a particular requirement - or can add to the list - then please drop us a line via the eBay messaging system and we will do our best to help.

Thanks for looking - please feel free to email with any questions, and view our other listings for further Lexicon parts and upgrades.