Predicted (using the statistical model) difference between SLM (Sound Level Meter) and application measurements with change in frequency for the Bolden Application. For panel A and B, dashed lines represent a sound level of 49.5 dB, and solid lines represent a sound level of 107.4 dB. (A) Differences for Device 1. (B) Differences for a Device 2. For panel C and D, dashed lines represent pseudo-calibrated devices and solid lines represent non pseudo-calibrated devices. (C) Differences for Device 1. (D) Differences for a Device 2.