ASW4000 picking up radio

[chin kwan]

I have my ASW4000 hooked up to a Proceed PAV/PDSD and later tried it with Yamaha.

I get low level radio (clearly audible as speech) but no hum.

Can somebody suggest how to get rid of it.

I have tried two processors so that rules out the source.

The subwoofer cable in use is a Canare L5CFB triple sheilded Co-axial run approx. 15 feet long.

It's not heard in the other 5 speakers, N803, SCM1 and HTM1.

[RobP]

What type of radio are we talking about here? Like a regular radio station or someones HAM radio or CB Radio coming through?

[P1et]

When I was younger my grandpa gave me his record player. I hooked it up to these massive 70s Sony speakers and I swear I could hear Russion radio coming through the speakers! The strange thing was that I lived in Holland. I never did find out why it did that...

[chin kwan]

Definitely a radio station.. as I can hear what is being said..

Pls. help..

I want to get rid of it but don't know how..

[Arneson]

I would assume you have an AM beacon station transmitter on a hill near your house.
Something on that system is acting as an antenna. It could even be one of the triple shields.
This technique sometimes works, get a roll of Alcoa tin foil and make a large pirate hat.
Wear this on your head as you turn up the volume, this should totally block that signal.

[chinets]

Cool!!

Radio Station for free.......cool! :E

Hope it is one of those NEW Digital stations that gets you all that Fab Dab music for free! :rofl:

You must have a grounding problem...I presume? :roll:

Pls. Keep us posted? Very interesting... Any U.F.Os out there? :lol:

Cheers ,and sorry to hear about your problem. Hope it gets solved soon!

[worldys]

many years ago, i had a pair of polk audio floor speakers with built in subs, subs started picking up radio similar to your situation, happened commonly with the first generation of that model, turned out to be a grounding issue and polk ended up swapping out the amps with a second generation amp that had corrected the design flaw

[RobP]

This technique sometimes works, get a roll of Alcoa tin foil and make a large pirate hat.
Wear this on your head as you turn up the volume, this should totally block that signal.

:rofl: :rofl:

[RobP]

You may want to try another sub cable, maybe one of higher quality. Contact Cat Cables by clicking on their logo above, Doug should be able to help you better with your problem and find a solution that will work for you.

[chin kwan]

Thankx guys for all your help..

I called B&W America Tech Support and spoke to Eric there.. He says it's not broken. It's a known ISSUE with the ASW4000. It is because of the circuit layout on the subamp.. It will pick up radio station even without a signal going on into it as long as it's plugged in. His suggestions is to move it around the room and it might disappear.

I guess I will have to live with it.. Strange that nobody on this board ever posted an issue like mine.. I am sure I am not the only one with an ASW4000 with this problem..

[chinets]

Love that Alcoa tin foil hat!!

It could even be one of the triple shields.
This technique sometimes works, get a roll of Alcoa tin foil and make a large pirate hat.
Wear this on your head as you turn up the volume, this should totally block that signal.

I represent as distributors of Alcoa In the Middle East ,and I had to send this quote to Alcoa's headquarters for some real laughter!! :T

That was hilarious!! Thanks for the laughs!! :rofl:

Alcoa Top exec.'s were in tears!! ;x(

Cheers!!

[RNKC]

Maybe the B&W guy was actually trying to upsell you to an ASW800-series.

[ArtyG]

I am a ham radio operator so I am familiar with the remedies to this....

First off... unplug the speaker cable from the sub.

Does the sub still play the radio station? If YES...

contact your B&W dealer as the problem is internal to the subwoofer and I can be of no help there (seems like you already did that)... other than that you can perhaps rotate the subwoofer case slowy to the right or clockwise or left counter clockwise direction, in place, to see if you can find a NULL angle which may eliminate the inductance of the radio signal.

IF NO....

Then attach the speaker wire to the sub....

Does it now play the radio station?

If so, go to your local Radio Shack and buy two ferrite cores. These are the passive devices that you see some times on the ends of VGA computer cables. The ferrite core installed at each end of the speaker cable may change the characteristic of the speaker wire. Also, if your speaker cable is coiled up in a loop in any way please uncoil it. Coils will sometimes act as a capacitor and help amplify the radio signal so please have straight runs of wire if possible with no coils of wire anywhere.

If that does not work, then possibly what is happening is that the speaker wire length is in a harmonic length with the AM radio's frequency and is acting as an antenna or massive inductor (odd but true, ham radio operators try to match their broadcast antennas to a full wave or half wave multiple of the frequency band they will be working and your speaker wire does not know it is NOT an antenna).

You can perhaps change the length of the speaker wire to become out of phase with the AM radio station frequency by either lengthing or shortening the speaker wire to the subwoofer. Again NO COILs of wire.