On Wed, 5 Mar 2003 18:15:21 -0800, "Mike Rehmus" <mike@no-spam-byvideo.com> wrote:

>"Neuman - Ruether" <d_ruether@hotmail.com> wrote in message

>news:3e6d00c8.3942402@newsstand.cit.cornell.edu...

>> On Wed, 5 Mar 2003 11:50:49 +0000 (UTC), "Maurice"

>> <maurice_vidents@btconnect.com> wrote:

>> >Now that sounds logical and beggers the question, what size of capacitor

>> >(electrical and physical specs). I suppose the logical way to mount it

>would

>> >be by using another XLR plug in line, with (hopefully) the capacitor

>within

>> >that plug, connected between which pins?

>> It is not an electrical problem (DC would not

>> cause hum...;-) but a mechanical one - better isolate

>> the mic from the vibration of the camcorder and the

>> hum will go away...

>> David Ruether

>Sorry but you are wrong here, David. It is well documented that the 3 VDC

>will cause some microphone to generate a hum.

>

>Take a look on the DV Mag website, the Jay Rose column. Sometime ago he

>discussed this issue and presented the solution.

This may well be true for some mics (though it is a mystery

to me how DC could cause this AC problem...;-), but for some

mics, it is clearly a mechanical vibration-pickup problem

(Sennheiser MKE-300 on VX2000 and TRV900...). The shoe

is plastic on the MKE-300, so physically isolating the mic

makes no electrical difference, but does remove the hum...