Monoprice 611502 Mini Headphone Amplifier for Guitar,"Tube Overdrive" Description As a musician you know you need to practice regularly to hone your skills and learn new songs. However you can't always break out the amps and crank up the volume. For those times when quiet is required you can both practice and hear the amplified output from your instrument using this Mini Headphone Amplifier for Guitar from Monoprice! This amplifier is designed to provide amplification to the output of instrument level devices such as electric guitars and bass guitars. It features a 1/4" TS plug which plugs directly into your instrument's output. It is powered by two AAA batteries (not included) and has a 3.5mm TRS output for listening with headphones. An additional 3.5mm TRS auxillary input is provided for connecting another audio source such as an mp3 player. The audio from the Aux jack is mixed with the audio from the guitar so you can play along to an existing recording. This amplifier is produces a "Tube Overdrive" sound with distortion and delay reminiscent of Classic Rock performances. The amplifier includes analog Gain Tone and Volume controls. Note: The distortion effect that this amplifier produces means that there will necessarily be some background hiss/noise even at normal volume levels. If you listen to the amplifier without it being plugged into a guitar the noise level can be loud and pronounced. However when it is plugged into a guitar the signal returns to a desirable noise level for playing. Features: As a musician you know you need to practice regularly to hone your skills and learn new songs For those times when quiet is required you can both practice and hear the amplified output from your instrument using this Mini Headphone Amplifier for Guitar from Monoprice! This amplifier is designed to provide amplification to the output of instrument level devices such as electric guitars and bass guitars Product Details: Brand: Monoprice Compatible Devices: Guitar Output Wattage: 4 Item Weight: 0.15 Pounds Power Source: Battery Powered Item Weight: 2.4 ounces Product Dimensions: 4.5 x 6 x 1.3 inches Item model number: 611502 Batteries: 2 AAA batteries required. Is Discontinued By Manufacturer: No Date First Available: December 6, 2012 Compatible Devices: Guitar Connector Type: 3.5mm Jacket, 6.35mm Jack Output Wattage: 4 Power Source: Battery Powered