Casella CEL-246 [CEL-246/K1] Digital Logging Integrating Sound level Meter Type 2 w/Calibrator and Case. Casella CEL’s CEL-240 series of general purpose digital sound level meters combine the power of Digital Signal Processing (DSP) with the affordability and simplicity of traditional analog sound monitoring instruments. The CEL-240 series includes two primarily instrument types, the CEL-240 and CEL-242 basic sound meters, and the CEL-244 and CEL-246 integrating meters. The CEL-242/246 feature basic datalogging capabilities. CEL-240 sound level meters are suitable for a range of simple noise measurement applications, are ideal for industrial hygiene measurement of workplace noise, and comply with ANSI and IEC Type 2 accuracy specifications. All CEL-240 series sound level meters support two measurement ranges and can display maximum and instantaneous values. In addition, the CEL-244/246 support the time average values Leq or Lavg. The CEL-240 supports impulse, fast, and slow time weightings on A or C scale. Other CEL-240 features include a wide sound monitoring range from 30–130 dB, a monochrome LCD screen, scrolling sound level display, and auto-calibration at either 114 or 94 1 kHz decibel levels. Digital output of audio is possible through USB and the CEL-240 can also provide an audio feed to a computer or external recorder through a 2.5 mm audio jack. Standard measurement and optional computer output kits are available. CEL-240 series instruments are powered by three AA alkaline batteries for up to 35 hours of use and can also be powered continuously through a computer or a mains-to-USB.