M300SE-B does not have a filter Upgraded M300SEwith filter SMSL SP200 THX AAA 888 Technology Balanced Headphone Amplifier with XLR RCA InputUSD 219.99/piece New Version SMSL M300 MKII Audio DAC AK4497 Native DSD512 PCM768kHz USB Optical Coaxial Bluetooth 5.0 Input Balanced Line OutputUSD 179.9...