This article is part of a series; see Speech Reinforcement. This is a stub; more content may be added later.
High-impedance (70 V) wiring is recommended for room speakers. High-impedance systems provide a variety of advantages, including much greater flexibility with number of speakers, significantly smaller wire gauge requirements, and greatly simplified wiring schemes.
Always be sure to use large enough wire to provide adequate damping, etc. Larger wire must be used when directly powering low-impedance speakers; for example, see Wire gauge on Wikipedia for low-impedance gauge recommendations.
Connectors for high-impedance or low-impedance cables are normally twist connector (such as speakON), 1/4 inch TS, or bare wire.
Speaker wire does not need to be shielded or twisted. In fact, using shielded cable is discouraged because it can increase the risk of a short. Note that shielded cable should be used for powered speakers where the signal is line or microphone level; the connectors in this case will often be XLR or 1/4 inch TRS (see Wiring and Cables).
Consider using line array speakers, such as the TOA SR-H2L
TOA offers the following high quality equipment for high-impedance (70 V) systems:
TOA DA-250DH amplifier
TOA DA-250FH amplifier
TOA MT-251H transformer