G.R.A.S. Sound & Vibration
Sound-intensity Probe Type 50AI - Page 5
Fig. 1.2 The type of carrying case delivered with the Type 50AI
1.1
Main Components
The main components of the Sound-intensity Probe Type 50AI are:
• Sound Intensity Microphone Pair Type 40AK
• Two Microphone Preamplifiers Type 26AA
• Four solid spacers of various lengths and a spacer cup (see Fig. 1.5)
• Remote-control handle with (where applicable) up to two push buttons for controlling meas-
urements
See also Fig. 1.8.
The Type 50AI is delivered in a carrying case similar to the one shown in Fig. 1.2, complete with
microphones, preamplifiers, standard accessories and a remote-control handle.
1.1.1 Microphones
The microphones (Fig. 1.3) are high sensitivity, free-field ½″ condenser microphones with a
uniquely-designed pressure equalization system that ensures extremely well defined phase
characteristics. The microphones and preamplifiers are mounted on the end of the telescopic
arm of the Remote-control handle. To cover the full frequency range from 50 Hz to 10 kHz, the
Type 50AI is delivered with four solid interchangeable spacers for spacing the microphones at
12 mm, 25 mm, 50 mm and 100 mm.
