GRAS PR0003 AutoArray Cross Configuration

Introduction

Today’s drivers expect more than just horsepower—they demand a quiet ride, free from intrusive noise, and an immersive audio experience. Whether it’s an internal combustion engine vehicle or an EV, in-cabin acoustic quality has become a key differentiator in automotive design. From benchmarking sound systems to tuning them for optimal listening and minimizing unwanted noise for improved NVH performance, precise and repeatable measurements are essential.

With the GRAS AutoArray, automotive manufacturers gain the precision, consistency, and ease of use needed to deliver world-class in-cabin audio experiences.

The AutoArrays are engineered to deliver quick, reliable, and repeatable in-cabin acoustic test results. Their structural design, seat-mount integration, and positioning tools are purpose-built to streamline setup and ensure consistent microphone placement.

Each array features six 1/4" measurement microphones arranged to emulate the spatial region around a listener’s head. The microphones are positioned in three ear-like pairs, simulating the ears of individuals of varying heights. This configuration represents not just fixed listener locations but also the area in which a listener might naturally move their head—critical for capturing an accurate in-cabin sound field.

Typical Applications and Use

Designed specifically for in-cabin acoustic testing, the GRAS AutoArrays are ideal for:

• Audio system performance testing and characterization
• Audio system tuning and optimization
• Cabin acoustic benchmarking and comparison
• Sound field mapping and analysis
• In-cabin NVH (Noise, Vibration & Harshness) measurements

They can also be deployed in any acoustic testing scenario that benefits from multi-microphone array setups.

Key Features

• Test-ready configuration: Based on widely adopted test setup used by companies such as Harman.
• Optimized for 1/4" microphones
• Single-cable convenience: Internally wired, all six microphone signals are routed through a single 7-pin LEMO connector, reducing clutter and setup time.
• Flexible pitch adjustment: Fix the angle at 30° or adjust freely; includes a magnetic inclinometer for precise angle measurement
• Precision positioning tools: Height-adjustable seat mount, integrated ruler system, ball levels, and a base-mounted ball joint enable exact placement and repeatability.
• Durable, lab-grade construction

Compatibility

The AutoArray is compatible with any 1/4" CCP microphone featuring a microdot connector but optimized for use with GRAS high-sensitivity models like the 46BL-1 pressure microphone and the 46BC multifield microphone, which offer ideal frequency responses for complex cabin environments. Other GRAS microphones that can be used with AutoArray are the GRAS 46BD 1/4" CCP pressure microphone and 46BE 1/4" CCP free-field microphone.

For more comprehensive information regarding microphone compatibility, check the AutoArray product manual.

The AutoArray is delivered with a 3m 7-pin LEMO to 7-pin extension cable and a 7-pin LEMO to 6x BNC splitter cable. Therefore, the array can be connected directly to any signal conditioner, analyzer or data acquisition system (DAQ) with CCP/ICP/IEPE microphone power supply that has BNC inputs.

Otherwise, it can also be connected to a sound card or audio interface with XLR inputs with +48V Phantom Power to drive the GRAS CCP microphones on the array. To do this, the 6x BNC connectors from the splitter cable need to be connected to the XLR inputs using 6x GRAS AG0003 adapters.

Quality & Warranty

GRAS products are made of components from our proven standard portfolio and are all manufactured with high-quality materials and branded parts that were chosen and processed to ensure life-long stability and robustness.

Thanks to the high-quality materials and assembly, our warranty against defective materials and workmanship is 2 years.

Exceptions: Even though this PR0003 AutoArray is meant to be used with measurement microphones, these are sold separately. GRAS measurement microphones like 46BC, 46BL-1, 46BE and 46BD are included in GRAS’ regular measurement microphone warranty scheme of 5 years.

The warranty for cables is 6 months

Dimensions in mm

Included items

Microphones are not included and should be purchased separately.

Optional items

GRAS Sound & Vibration reserves the right to change specifications and accessories without notice.