Peavey SP 4G Speakers Information

Peavey SP 4G speakers are used in sound reinforcement systems (also called PA or public address systems) for live or recorded music. The speakers are designed for portable use, but may also be used in fixed-installation settings. SP 4G speakers are passive (non-amplified), requiring an external power amp to be used, and contain two 15-inch speakers and a high-frequency horn.

Configuration

The Peavey SP 4G speaker can be used as a full-range or bi-amped speaker. In full-range mode, a single amplifier is used to provide power to all speaker components. In bi-amp mode, one amplifier is used for the speakers, with a second amplifier for the high-frequency horn. A built-in frequency crossover separates the sound frequencies, and routes them to the individual speakers for optimum sound. Configure the speaker for full-range or bi-amp operation by plugging the power amplifier into the desired power amplifier input jacks in the back of the cabinet. The jacks are labeled for different configurations.

Power Handling

Power handling is the ability of a speaker to withstand the power of an amplifier. When used as a full-range speaker, the power handling is 600 watts continuous at 4 ohms. When used in a bi-amp configuration, the low-frequency power handling is 700 watts continuous at 4 ohms, while the high-frequency power handling is 40 watts continuous at 8 ohms. Peavey uses a variation of RMS (root mean square) to determine power levels and measure safe average operating wattage. Power amplifiers must not exceed the wattage and ohm ratings of the speaker in order to avoid damaging the equipment.

Construction

The SP 4G cabinet is made of 3/4-inch plywood and is covered in black carpet. Plastic corners and a metal speaker grill provide protection, while recessed handles on both sides provide a firm holding spot for manual transport. The cabinet is trapezoidal in shape, which improves frequency reproduction and allows additional cabinets to be placed side by side to form a front-radius speaker array. Measuring 49 1/4 inches high, 21 1/2 inches wide and 22 3/4 inches deep, the SP 4G weighs 135 lbs.

Speaker Protection

Protection circuits are used to prevent speaker damage when periodic voltage peaks occur, to which high-frequencies speakers are especially susceptible. The Peavey SP 4G includes the Sound Guard protection circuit for the high-frequency speaker. The circuit acts as a sound compressor, limiting and decreasing the audio signal when it exceeds power beyond the speaker's capacity. Sound Guard works automatically, in full-range and bi-amp mode, and does not require user settings or interaction. The system requires periodic checking of the internal light bulb, which acts as a fuse. The bulb will blow if the system is continually overloaded, and will eventually burn out with age. It is easily and cheaply replaced with a Peavey spare, or a standard #1156 automotive bulb.

Speakers and Frequency Range

The cabinet includes three speakers to produce the full-range of audible sound frequencies. Two 15-inch Peavey 1505-8 KADT Black Widows are used for the woofers, and a Peavey 22XT compression driver is used for the CH 941 high-frequency horn. Compression drivers are small speakers attached to a nonflexible dispersion device called a horn. Horns are similar in design to a megaphone, and help project sound. The overall frequency range of the SP 4G is 50 Hz to 17.5 kHz (low to high frequencies) with a usable low-frequency limit of 39 Hz.

References

• Peavey Electronics: SP 4G Specifications

Resources

• Sweetwater: PA Speaker Buying Guide
• Musicians Friend: PA System Buying Guide