Pair (2 off) 20kHz anti-aliasing audio filter modules for Lexicon 480L or Eventide H3000
Replacements for Murata AFL89WB20000
(Other frequencies also available for other units - see below)

The Lexicon 480L and Eventide H3000 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 20kHz (20,000Hz, hence the 20000 suffix in the Murata part number). It is recommended that they are replaced in stereo pairs, not because there is any significant difference in performance between original and replacement filters (there isn't) but to keep happy anyone who can hear the difference between 1980s opamps and present-day ones ;-)

Not-so Small Print

1. Replacement of filter modules requires advanced disassembly of the 480L/H3000 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.

2. A photo is included in this listing of a set of six modules fitted into a 480L. It looks great, but for the avoidance of doubt, this listing is for two filter modules only and nothing else.

Murata Filters in Other Units

We know that similar filter modules are used in other equipment and intend to expand our offering in time to cover those applications too. 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)

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.

Payment (UK pounds only please) may be by internet bank transfer (preferred) or PayPal. For international sales, only PayPal is accepted. All sales are final and shipment will be made once funds have cleared.

This is a business sale and UK VAT at 20% is included in the price.