
Whirlwind PB12 Pressbox Microphone Output Expander
Expand Your Audio Output Capabilities with Professional-Grade Isolation The Whirlwind PB12 Pressbox is a passive microphone output expander designed for press conferences, forums, and live events. It takes one line-level input and distributes it to twelve microphone-level outputs, each transform...
*Price sourced from Amazon.com. Last updated:Jul 14, 2026.Price and availability are subject to change.
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Overview
Expand Your Audio Output Capabilities with Professional-Grade Isolation
The Whirlwind PB12 Pressbox is a passive microphone output expander designed for press conferences, forums, and live events. It takes one line-level input and distributes it to twelve microphone-level outputs, each transformer-isolated to eliminate noise and ground loops. Housed in a rugged steel case, the PB12 ensures reliable performance and superior audio quality.
- Type: Passive Pressbox
- Input: 1 Line Level Input
- Outputs: 12 Microphone Level Outputs
- Isolation: Transformer Isolated Outputs
- Transformer Type: Whirlwind TRSP-2
- Case: Rugged Steel
- Signal-to-Noise Ratio: 65 dB
- Connector Type: XLR
- Number of Channels: 12
- Dimensions: 11.9 x 11 x 2 inches
- Weight: 6.1 pounds
Key Features
Passive Pressbox with 1 Line In to 12 Mic Out
Specifications
Pros & Cons
👍 Pros
- Functions as a passive pressbox, ensuring robust and reliable operation without requiring external power.
- Effectively expands a single line input to twelve microphone outputs, ideal for press conferences and broadcast events.
- Designed by Whirlwind, a brand known for professional audio equipment, suggesting durable construction and reliable performance.
- Simplifies signal distribution by providing multiple isolated outputs from one source, maintaining signal integrity.
- Offers a practical solution for scenarios where a single audio feed needs to be shared with numerous recording or broadcast devices.
👎 Cons
- As a passive unit, it does not provide any active gain or signal conditioning, relying on the source signal's strength.
- The unit is strictly 1 Line In to 12 Mic Out, meaning it cannot combine multiple inputs or provide different output types.
- Lacks individual level controls for each output, which could be a limitation when feeding devices with varying input sensitivities.
- No information is provided about isolation transformers or ground lift switches, which are important for preventing ground loop noise.
- The design is specialized for pressbox applications, and may not be versatile for other studio or live sound needs beyond signal splitting.