The PLACID PQ401 is a compact 4-channel USB data acquisition system designed for acoustic and vibration measurement in both laboratory and field applications. All four channels are sampled simultaneously using 24-bit ADCs, providing the dynamic range and phase coherence required for multi-channel acoustic measurement. The PQ401 is USB bus-powered — no external power supply required for bench or field use with a laptop. Two variants are available: PQ401-A (128 kHz maximum sample rate) and PQ401-B (196 kHz maximum sample rate for high-frequency applications to 80 kHz).
The PQ401 is the compact single-unit solution for applications requiring up to 4 simultaneous channels: impedance tube measurement, field acoustic surveys, two-microphone sound intensity measurement, small vibration tests, and modal analysis on small structures. When more channels are required, the PQ801 (8-channel) and PQ1601 (16-channel) systems use the same chassis and the same software interface.
The PQ401 is designed for field as well as laboratory use. Bus-powered operation from a laptop USB port provides a completely portable 4-channel measurement system with no mains power requirement. An internal 16 GB SD card enables standalone data logging — the PQ401 can record continuously to SD card in the field without a connected PC, and data can be transferred and analysed on return to the laboratory. The integral rechargeable battery provides approximately 6 hours of continuous measurement with IEPE current supply active on all 4 channels.
The IP54 housing is splash-resistant and dust-protected, making the PQ401 suitable for outdoor measurement in light rain and in dusty industrial environments. Operating temperature range is -10°C to +50°C. For permanent installation monitoring applications, the PQ401 can be supplied with an optional weatherproof enclosure with PoE (Power over Ethernet) connectivity.