How To Choose a Guitar Speaker Cabinet – Part 1. on Dec 11, 2014, 9:21 PM. Guitar speaker cabinets are available in a wide array of sizes and styles, with options both cosmetic and functional. The same speaker mounted in different enclosures can sound different, in ways that are subtle and significant. The WJBA2 1000 Watt Bass Guitar Amplifier, offers 1000 watts (in bridge mode) into 4 or 8 Ohms. Packaged with similar features and controls of the WJBPII Bass Pre-Amp (n.b. WJBA2 is single channel) along with a single channel 6 band EQ built right into the head and yes, 1000 Watts into 4 or 8 Ohms! May 27, 2010 · (ohms). When selecting a cabinet to pair with your amp head, always check your amp to figure-out how many watts of power your amp will put-out in different impedance modes. Amps nowadays, generally speaking, are pretty slick and know what impedance to run at when you plug-in your cables, connecting them to the cabinets. Most bass amp manufacturers will state this with the maximum wattage output of the amp like: 400 watts @ 4 ohms. To get the full 400 watts out of the amp, you need to hook up either a single 4 ohm bass guitar cabinet, or two 8 ohm cabinets (which equal 4 ohms total). This is a beginners guide to matching speakers and amps and what you can do without stressing or breaking them. A: Matching an amp head with the right speaker cabinet can be a daunting task. However, if you know some basic things about amp head impedance, power, cabinets, and what to look for, it can make the task easier so you can choose an amp and speaker combination that will achieve the desired results.