Speaker line characteristics
Phil Allison wrote:
"klem kedidelhopper"
This question was posed on another group but wasn't really answered.
There is a PA installation with several zones . One zone is a bell
tower which has a separate speaker in it. The speaker is inaccessible.
The DC resistance of that line is 11 ohms. How can an installer
determine if this is a 70, or 25 volt speaker and which tap it may be
set at? Or perhaps it's just an 8 ohm speaker with 3 ohms of cable
resistance added? Is there n easy way to do this without an impedance
bridge?
** One only has to add say a 100 ohm resistor in series with the speaker -
if the level drops dramatically it is 8 ohms.
An impedance meter is invaluable when troubleshooting line voltage PA
systems - but even that will not tell you if a line matching tranny is 70 V
Sigh.
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