Barcus Berry BREEZEIV Multi-Sensor Acoustic Guitar Preamplifier System The Breeze IV system features a three-band EQ with an additional Mid-frequency control and dual output capability. The Mid-freq allows you to adjust the center frequency of the midrange EQ control to get your sound just right. A built-in auxiliary input provides the ability to easily add a secondary mic or pickup. Both 1/4-Inch and XLR output jacks come standard on the Breeze IV system. Specs are volume, 3-band EQ, mid-frequency control, piezo under-saddle pickup, digital tuner, blend, phantom power, dual output jack.