For those troubled by howling, 【Price negotiations welcome!】 It seems new ones are difficult to obtain. A digital processor with 24-bit high resolution and an automatic feedback (howling) removal function. Digital 24-Bit Feedback Suppressor/Parametric Equalizer ■Japanese manual and power cable included (The black stand-like object in the photo is for photography purposes and is not included) The FEEDBACK DESTROYER PRO's unique search algorithm identifies feedback frequencies in a fraction of a second, sets a very narrow 1/60 octave filter, and almost eliminates the unwanted signal. The result is a rich and full sound without feedback (howling). <https://www.behringer.com/product.html?modelCode=0822-AAH> Previously, the DSP 1100P was the higher-end model of the FBQ 1000, with the "PRO" designation. Reference page (FBQ 1000) <https://www.soundhouse.co.jp/products/detail/item/164868/> BEHRINGER DSP1100P Feedback Destroyer Pro - Model: DSP 1100P - Function: Automatic feedback suppression - Number of bands: 24 bands - Resolution: 24-bit