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PACKAGE CONTENTS
Please take an inventory of the package contents to ensure you have all the
items listed below. If anything is missing or damaged, please contact Monoprice
Customer Service for a replacement.
1x Metro 6.5" In-Ceiling 70V/100V Paging Speaker
1x User's Manual
CONSTANT VOLTAGE VS 8-OHM SPEAKER
SYSTEMS
A constant voltage speaker system differs from a traditional 8-ohm speaker
system in that it uses a step-up transformer at the audio source to raise the
voltage and lower the current on the transmission line. At the speaker end, a
step-down transformer converts the signal back to a normal speaker level
voltage. This reduces power loss during transmission, which allows for the use of
longer speaker wire runs using smaller gauge wire.
Additionally, a constant voltage speaker system allows for the use of multiple
speakers on each channel, without the need for complicated impedance
calculations and configurations. In a constant voltage system, all speakers on a
given channel are connected in parallel and the complicated impedance
calculations are replaced by simple wattage calculations.
For example, if you want to connect two speakers per channel in a traditional 8-
ohm speaker system, you must either connect them in series, which results in an
overall 16-ohm impedance, or in parallel, which results in an overall 4-ohm
impedance. In the first case, the 16-ohms impedance effectively halves the
output power of your amplifier, resulting in lower overall volume levels. In the
latter case, the 4-ohms impedance means that your amplifier will have to work
harder and must be rated as stable at 4 ohms. Adding a third speaker to the mix
would complicate it further, producing either a 24-ohm or 2.67-ohm overall
