Behnirnger monitor radio noise..

Archived from groups: rec.audio.pro (More info?)

Hi,

I have a pair of Behringer Truth B2031's (active), that tend to pick up
and amplify radio interference -- sometimes quite loudly. It wasn't a
problem for me before, but I recently moved to down-town Salt Lake City
-- a much busier environment.

Is there anything I can do to isolate these monitors so they won't pick
up the noise?

--
Dilvie on the web:
- http://www.dilvie.com/
- http://download-electronica.blogspot.com/
- http://movie-trailers.blogspot.com/

Archived from groups: rec.audio.pro (More info?)

On 13 Jan 2005 16:34:08 -0800, "Eric" <dilvie23@gmail.com> wrote:

>Is there anything I can do to isolate these monitors so they won't pick
>up the noise?

How well sealed are the casings? You'll need to improvise some sort
of shielding, inside or out.

Are you using them next to a computer monitor? Are the drivers
effecting the screen?

http://www.johnlsayers.com/phpBB2/viewtopic.php?t=297

Has a bit about halfway through about how to shield drivers that
aren't.
jtougas

listen- there's a hell of a good universe next door
let's go

e.e. cummings

Archived from groups: rec.audio.pro (More info?)

On Thu, 13 Jan 2005 22:47:41 -0500, jtougas
<jatougasNOSPAM@charter.net> wrote:

>>Is there anything I can do to isolate these monitors so they won't pick
>>up the noise?
>
>How well sealed are the casings? You'll need to improvise some sort
>of shielding, inside or out.
>
>Are you using them next to a computer monitor? Are the drivers
>effecting the screen?

I'm not sure screening the speaker will make any difference. The
classic source of radio pickup is a bad plug connection acting as a
diode. Plug the speakers up to something else - is the radio still
there? What about if you monitor on headphones?

If you've moved next door to a transmitter, you may just have to move
again ;-)

CubaseFAQ www.laurencepayne.co.uk/CubaseFAQ.htm
"Possibly the world's least impressive web site": George Perfect

Archived from groups: rec.audio.pro (More info?)

They pick things up things like the microwave, paper shredder, and
miscellanious noises from outside, etc...

They pick up noise when they're not connected to anything, but they
tend to pick up more noise when I have them plugged into my mixer, and
I plug other things into it (even when the mixer input and output
volumes are zero). The mixer in question is an event ez-bus.

--
Dilvie on the web:
- http://www.dilvie.com/
- http://download-electronica.blogspot.com/
- http://movie-trailers.blogspot.com/

Archived from groups: rec.audio.pro (More info?)

"Mark" <makolber@yahoo.com> wrote :

> Usually RF interference gets into audio equipment via the audio cable
> or via the power cables. Check the chassis ground connections on your
> input and output cables.
>

Actually sound to me this guy has a probem with bad earthing and conductive
loads dirtying up his 'powergrid'..

--
Bill Gates can't guarantee Windows,
how are you gonna guarantee my safety..
--John Crichton - Farscape pilot

Just for posterity -

I had exactly the same problem for ages, its not balanced cables or power conditioners that will fix the problem. I finally found a forum where this question was answered correctly. It is something easy to fix if you are prepared to open the case and void your warranty.

It is the wires between the electronics at the back and the two leds that are at the front of the unit that acts as an antenna. it is easy to open the electronics (with the power cable removed of course), and disconnect this wire.

I opened the case by removing the six screws that connect the STEEL casing to the WOODEN enclosure. There are twelve screws on the back, and the ones that are in the middle of the steel casing (surrounded by settings and diagrams) are NOT the right ones. The ones at the side that screw into wood are the ones that I used to open the casing.

Inside, there are two plugs with 4-5 wires inside, and one has thinner wires (four black one red) and was the right one to disconnect - it was glued a little so I had to carefully prise it out. The other one has larger thicker wires and is connected to the two drivers (do not disconnect this one). I disconnected the small ones and am now happily enjoying much reduced noise (but no leds for power on or overload - boohoo).

As usual - this type of repair is at your own risk - but I had no trouble, and regained the use of quite reasonable monitors.

Cheers

Wow! That worked. Thank you SOOOOOOOOO much. I have the Behringer Truth B2031 and live about 200 yards from a huge radio antenna on an office building. I got constant radio noise through the speakers and couldn't get rid of it. Line conditioning did absolutely nothing. I followed your instructions about disconnecting the wires to the front led and it got rid of about 85% of the radio noise. I then went and put ferrite chokes on the wires going to the speakers and that got rid of the last 15%. I am SO grateful to you