KWA 150/150SE Power Amplifier Owner’s Manual Manufactured by ModWright Instruments, Inc. 21919 399th St.
USA www.modwright.
PLEASE READ FIRST: General operation and protection circuitry of amplifier. • Startup: o To power unit up, simply depress the large MWI logo on the faceplate of the amp. When you do this, the unit will turn on and logo/button and internal blue lights will flash for approximately 45 seconds, while amp output is muted. This is normal and is part of the startup and stabilization sequence.
unit will void the factory warranty. If unit protection triggers and amp will not restart, please contact factory.
General Operation: Note: It is always recommended that you power the amplifier on last, when powering up your audio system. When powering your audio system down, it is always recommended to power the amplifier off first. • Stereo operation: o Connect Left and Right XLR or RCA cables from preamp to Left and Right inputs on back panel of amp. o Connect (+) and (-) Left and (+) and (-) Right speaker cables from binding posts on back of amplifier to speakers.
Caution: Do not connect the Mono binding post to any speaker circuitry that grounds any speaker lead. If either terminal of the Mono binding post are connected to GROUND when operating in bridge-mono mode, damage to the amp may occur. It is not recommended to run the amplifier in bridged mono into 2ohm loads.
• High/Low Bias Operation: o High/low bias toggle is located on the rear of the amp, above the MONO binding posts. The bias status indicates how much current the amplifier output devices receive at idle. The best sonics are typically achieved in high-bias. This bias level also generates the highest amount of radiated heat and draws the most mains current. The unit may operate in either high or low bias state. Bias may be switched from High to Low bias during operation.
Specifications: Power Ratings: • 150W @ 8 ohms (Stereo) @ .06% THD. • 450W @ 8 ohms (Bridged Mono) @ .06% THD. • 200W @ 4 ohms (Stereo) @ .06% THD. • 650W @ 8 ohms (Bridged Mono) @ .06% THD. Technical Specification: • Bandwidth: 10Hz - 100Khz (+0, -1dB) • Noise Floor: -100dB • Channel Separation: -75dB below 20Khz • Gain: 26dB • Input Impedance: Min. 15K at 50Hz; 23K at 1Khz Weight and Dimensions: • Dimensions: 17"W x 17"D x 8.
KWA 150SE Upgrades: • Upgraded input stage circuitry, resulting in lower distortion and noise levels. • Higher Quality Lundahl input transformer with larger signal capacity. • All ultra-pure copper, solid-core, cryo-treated audio-grade input signal wiring. • Output wiring upgraded to 12GA Cardsas Litz wire. • Redesigned output stage power supply design, provides both 25% more capacitance and significantly lower power supply impedance. • Increased output current capacity and speed.
WARRANTY: ModWright agrees to warranty product for a period of 5 years from date of purchase from a factory authorized ModWright Instruments Dealer. Warranty covers parts and labor for repairs due to equipment failure not related to customer abuse and/or neglect. Customer is responsible for shipping costs to and from ModWright Instruments or authorized service center.
President, Owner ModWright Instruments, Inc.
