A question on a B&W high pass filter


I have a B&W 800 series variable high pass alignment filter for my 803 matrix speakers. I have never used it & wondered if I need to? What would I be expected to hear? Or should I just sell it & forget it? Also, what is the thing worth? New, in box. I never hooked it up since i had no idea of why I would need to. If you can help me understand this question, please answer. Thanks.....
rws1950
It sucks throw it out! Your better off without it.They are noisy and really don't do a whole lot.If my memory serves me, most users either go without or sprang for the Northcreek or other aftermarket filter. I tried mine once and took it out ( 801 matrix ) and enjoyed my system much more without it.
Has any of you ever bothered to check why the stock B&W Filter sucks? Guess not or else these comments wouldn't be posted.

Look at the puny power-supplies that barely can do 50-100mA. Open that filter’s hood & take a deep look at the crap parts sitting inside (thanks to a 3rd party assembler that B&W entrusted the job to - so called Manby Electronics & probably at a contracted rate).

In short, the circuit is great but the assembling dudes did a shoddy job, hence it sucks.

After almost a decade, I took that Filter & worked on it. Fully reg PSU with 2.5+ amperes juice using encapsulated transformers in today's age of common SMPS. Heavyduty AWG 16 screened wiring to kick RF goodbye, all internal parts scrapped & substituted using Vishay Bulk-foil resistors that are very, very expensive, again expensive Teflon Multicaps & fully buffered active input stage with output impedance of 10 Ohms!

BTW - I've the Krell filter too. The fully modded B&W filter now walked over D'agostino's Filter like it had it for yesterday's breakfast.

My motivation was spruced up after 2+ decades; having vaguely remembered that I came across an article in 1988 written by a Matrix 801 S2 owner (an EE tech guy) in a magazine 'AUDIO' (that mag is years' history) towards the correct way to use the Filter with the implementation of a top-notch active buffer BUF03AJ/883 MIL spec to lower the impedance.

Tip: Filter MUST be placed either before the audio signal entering your Pre (between analog OUT from source to Pre) OR in the Tape-loop of the Pre (if it has one). Never between Pre & Power.

Now, enjoy your Matrix 800 series! They rock big time.
I found this thread via google when I was researching a question about these filters. I was able to get a B&W 801 high pass filter. This one doesn't have the dip switches to set the filter to a specific 800 series speaker. It is preset for the 801 series B&W speaker only. Would it be bad if I used this filter along with the B&W Matrix 805 bookshelf speakers? I haven't tried it yet and don't want to risk damaging the 805s I have.

Thanks