Endevco Corporation”s Model 4999 low-pass filter signal conditioner provides individual input ground isolation to eliminate ground loops often encountered with multiple channel measurements. The signal conditioner is particularly well suited for applications, such as rotating machinery test cells and the nuclear services industry, where a very low noise floor is required. The 16-channel, 2U rack-mounted system offers an ultra-low-noise design in a four- or six-pole, low-pass filter conditioner that supplies excitation current to IEPE (ISOTRON®, ICP®)-type sensors and remote charge convertors. Although ultra-low broadband noise is specified at <30µV RMS, the signal conditioner actually measures at <15 µV for high accuracy with low-level vibration signals for any data acquisition system. It is a good fit for use with the Endevco model 2771C low-noise remote charge converter and a PE sensor.