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Re: Fostex FR-2LE ?

Subject: Re: Fostex FR-2LE ?
From: animalsounds
Date: Wed May 14, 2014 1:58 am ((PDT))
Eric wrote:=0D
 =0D
=0D
 "Drawing more or less current from the phantom supply might result in a ch=
ange in the amount of noise in the phantom supply, but it should still be t=
he same in each leg."=0D
 =0D
=0D
 Agreed.=0D
 =0D
=0D
 "So the only means that I can see by which microphone imbalance could caus=
e an increase in observed noise is if there is an imbalance in the AC compo=
nent of the differential output impedance of the microphone."=0D
 =0D
=0D
 Yes, an imbalance in the AC component of the differential output impedance=
 of the microphone would of course also degrade the immunity of the recordi=
ng system against external noise sources. =0D
 =0D
=0D
 I believe however that the problem we are talking about is simply caused b=
y a poorly designed (or badly manufactured) microphone that just does not d=
raw equal currents from the pins 2 and 3. Proper balancing would normally r=
equire series resistors with tolerances less than 0.4%  - not only on the t=
wo 6k8 resistors inside the recorder, but also on the resistors (or equival=
ent transistor-based loads) inside the microphone!=0D
 =0D
=0D
 Regards,=0D
 Raimund=0D
 =0D
=0D





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