1. Análise de Fase e Tempo

O alinhamento preciso de subwoofers com o sistema principal exige uma análise detalhada da fase e do tempo de chegada do sinal. Softwares de medição como Smaart, SysTune ou SATlive são recomendados para avaliar a relação temporal entre subwoofers e alto-falantes full-range.

Método do Impulso

Mede a resposta ao impulso do sistema e ajusta os atrasos para sincronizar a chegada das frentes de onda.

Método de Fase

Utiliza um analisador de fase para casar a inclinação de fase entre subwoofers e alto-falantes principais, prevenindo cancelamentos na região de crossover.

Equação da Relação de Fase

A relação de fase entre dois sinais pode ser descrita pela seguinte equação:

Exemplo com Tecnare: Ao utilizar subwoofers como o SW218V junto a alto-falantes full-range da série IBZA, o alinhamento de fase é fundamental para evitar cancelamentos no ponto de crossover.

2.4. Cardioid Configuration

Subwoofers facing forward and backward are combined with opposite polarities and specific delays to minimize rear emission. This technique is particularly useful for reducing energy on stage and improving intelligibility in the audience area.

Example with Tecnare: Configuring a cardioid stack with SW218EB and SW115 reduces sound contamination in the musician’s area.

3. Use of Processors and Filters

Digital processing systems such as the Tecnare DP4896 allow advanced filtering and equalization to optimize subwoofer response. It is recommended to:

• Optimize Crossover Filters: Select appropriate slopes (Butterworth, Linkwitz-Riley, Bessel) to minimize phase shift in the transition zone.

• Apply Parametric Equalization: Correct resonances and compensate for peaks in the frequency response.

• Adjust Polarity and Phase: Test different configurations to achieve the best phase coherence in the transition zone with mid-high speakers.

Example with Tecnare: Using the DP4896 to adjust phase and equalization in a system with SW218EB and the V Series of Tecnare ensures powerful and precise bass reproduction.

4. Field Measurement and Optimization

Once the theoretical configuration is completed, in-venue measurements are essential to evaluate SPL distribution and phase coherence. It is recommended to:

• Map SPL: Measure sound pressure levels at various points to identify areas of excess or deficiency.

• Analyze Coherence: Verify phase correlation between subwoofers and main speakers.

• Iterative Fine-Tuning: Implement minor adjustments in delays, equalization, and levels to refine the system based on real measurements.

Example with Tecnare: During a stadium concert, engineers can use a real-time analyzer to adjust the SW218V and CLa312 system according to venue acoustics.

 Conclusion

The proper design and alignment of subwoofers in large events is a complex process requiring analytical tools, advanced acoustical knowledge, and a rigorous methodology. Combining real-time measurements, digital processors, and appropriate placement strategies maximizes system efficiency and provides a uniform, high-quality sound experience for the audience.