How to solve the delay problem in speaker debugging?
Usually, the sound reinforcement of outdoor bluetooth speaker is often more than two or two sets of outdoor bluetooth speakers. Therefore, when there are outdoor bluetooth speakers in the third or fourth group or more, due to the different positions of the outdoor bluetooth speakers in each group, we need to combine the outdoor bluetooth speakers with auxiliary (side fill, front fill, and delay tower, etc.) with the main amplifier. While the delay difference between the sound boxes is compensated, whether the phase curve is the same is also a problem that we need to consider.
Since the original phase curves of outdoor bluetooth speakers of different models or structures are different (except in special cases), the delay difference caused by different positions cannot only be added to the close group of outdoor bluetooth speakers. This will lead to: If the phase of the two sets of outdoor bluetooth speakers The curves are different. In the area covered by the two sets of outdoor bluetooth speakers, there will always be some frequency bands in the entire frequency band that are less superimposed or even offset, resulting in the system not being truly optimized.
So how to solve this problem?
First of all, we need to understand why the original phase curves of different models or different structures of outdoor bluetooth speakers are different. There are roughly 4 reasons:
1. The frequency division order is different or the frequency division slope is different. Each order of the high-pass filter and the low-pass filter has a phase shift of 45° at the crossover point. Different outdoor bluetooth speakers have different crossover structures, and some are two. Order, some are third order;
2. For externally driven outdoor bluetooth speakers, different unit processor channels have corresponding delay adjustments, that is, different programs have different delays. The amount of delay is determined by the delay difference between the units caused by the outdoor bluetooth speaker structure and the crossover slope, which results in different delays.
3. Different built-in crossover outdoor bluetooth speakers have different crossover adjustments. Some trebles have positive polarity, and some trebles have reverse polarity, so the phases of different models are different.
4. The number of frequency divisions is different. For example, three-way and two-way outdoor bluetooth speakers cannot achieve the same phase. Obviously, the reason is that the three-way frequency has one more frequency point than the two-way frequency, and the phase shift is more serious.
Therefore, the original phase curves of outdoor bluetooth speakers that are not the same model or different in structure will definitely be different. When they are used together, they will have an offset effect. Even if they are taken away to compensate for the equivalent delay difference, the offset will also occur.