Hey Max I don't live near a transmitter of any sort, but a ground loop would make sense. What this board has is quarter-inch inputs and one per channel. So, I use two inputs for stero output. I assume these are balanced inputs, but I am a little embarrassed to say I don't know exactly the difference between the two types. I used ot know this stuff, but I have forgotten it oer the years. I'm not sure how I could address the ground loop issue, but I have a few ideas and maybe disconnecting the laptop from ac power might yield some results, or just pulling the audio cable out of the mixer for the laptop and see what happens.
tnx, On Mar 2, 2009, at 9:18 PM, Max Robinson wrote: > You may have a ground loop. They are very difficult to break without > loosing a ground on something. If your mixer has balanced inputs it > might > be easier. I have a 12 x 4 channel mixer, an 8 track digital recorder, > sound module, signal processor, and monitor amplifier, all hooked > together > and to my computer. Only one computer though. It took a lot of making > special patch cords to get all the hum and other interference out of > the > system. Do you live near a TV transmitter? I do and that was a problem > too. > > Regards. > > Max. K 4 O D S. > > Email: [email protected] > > Transistor site http://www.funwithtransistors.net > Vacuum tube site: http://www.funwithtubes.net > Music site: http://www.maxsmusicplace.com > > To subscribe to the fun with tubes group send an email to, > [email protected] > > ----- Original Message ----- > From: "Scott Howell" <[email protected]> > To: <[email protected]> > Sent: Monday, March 02, 2009 4:44 PM > Subject: [BlindHandyMan] question on interference form computers > > > Hey folks, I have a rather interesting problem that I hope is > > acceptable for the list. Let me explain my setup and then I'll > explain > > the problem. > > > > I have a small mixer that has three or so inputs. I have my > employer's > > Dell laptop, my Macintosh, and a cable into which I plug my electric > > bass. All this is served by one pair of headphones. Now in order to > > save on space and so forth, I have a usb KVM switch. servicing both > > computers. THis KVM only handles a keyboard and mouse, but you could > > connect video, which I do not. So, when I have the Mac and PC laptop > > connected and running, everything is fine. If I shut the laptop lid/ > > put it to sleep, but leave it connected, I get this humming noise > that > > is not 60Mhz, but probably almost twice that. I can disconnect the > > laptop and then soud goes away or if I adjust the mixer controls > just > > so, I can cancel out the sound. For some reason it sometimes gets > > messed up and that usually is because I have made a slight > adjustment > > to something and then I have to start all over again isulating the > > sound by tweaking things. So, has anyone have any thoughts on how I > > might correct this problem, so I do not have to keeep messing with > the > > controls? It could be the mixer, but I suspect there is an issue > with > > both machines being connected to the KVM and this is a pretty cheap > > KVM. The KVM is not near the computers, it is under my desk. > > > > Thanks, > > > > > > > > ------------------------------------ > > > > Send any questions regarding list management to: > > [email protected] > > To listen to the show archives go to link > > http://www.acbradio.org/pweb/index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=33&MMN_position=47:29 > > Or > > ftp://ftp.acbradio.org/acbradio-archives/handyman/ > > > > The Pod Cast address for the Blind Handy Man Show is. > > http://www.acbradio.org/news/xml/podcast.php?pgm=saturday > > > > Visit The Blind Handy Man Files Page To Review Contributions From > Various > > List Members At The Following address: > > http://www.jaws-users.com/JAWS/handyman/ > > > > Visit the archives page at the following address > > http://www.mail-archive.com/[email protected]/ > > > > If you would like to join the JAWS Users List, then visit the > following > > address for more information: > > http://www.jaws-users.com/ > > For a complete list of email commands pertaining to the Blind > Handy Man > > list just send a blank message to: > > [email protected]! Groups Links > > > > > > > > > > > > [Non-text portions of this message have been removed]
