Devices for separating materials from a host fluid are disclosed. The devices include a flow chamber, an ultrasonic transducer, and a reflector. The ultrasonic transducer and reflector create an angled acoustic standing wave oriented at an angle relative to the direction of mean flow through the flow chamber. The angled acoustic standing wave results in an acoustic radiation force having an axial force component that deflects the materials, so that the materials and the host fluid can thus be separated. The angled acoustic standing wave can be oriented at an angle of about 20° to about 70° relative to the direction of mean flow through the flow chamber to deflect, collect, differentiate, or fractionate the materials from the fluid flowing through the device at flow rates of about 400 mL/min up to about 700 mL/min.