In article ,
Rich.Andrews
wrote:
"Dave Plowman (News)" wrote in
:


Considering the low output impedance of well designed equipment, more
like a short? ;-)


There is some equipment that is well designed but designed to drive a
high impedance load. In cases like that, loading it down with 600 ohms
instead of something like 50k ohms will result in a roll off of low
frequencies.

I'm not sure if things have changed. However the normal assumption for
domestic audio sources in the 1970's and 1980's was that the source (CD
player, Tuner, etc) should work as per spec into loads down to 10kOhm in
parallel with 1000 pF. The assumption being that any preamp input would
have an impedance that was this, or higher.

So far as I know, 600 Ohm input impedance would be unusual in domestic
equipment. Although I think some items may use it with balanced inputs. If
so, I'd assume the source would then be expected to use a matching output.

Hence in domestic practice. I would assume that having a 600 Ohm load on a
normal single-ended output would be unusual and not recommended.

Slainte,

Jim

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