How to solve the delay problem in speaker debugging?
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.
When we are debugging, can we solve the problem with the following methods?
A. Test the original phase curves of the two outdoor bluetooth speakers(main and auxiliary) at close range, and then adjust the phase of the auxiliary outdoor bluetooth speaker to be the same as that of the main amplified outdoor bluetooth speaker. After finding the delay difference, add it to the auxiliary outdoor bluetooth speaker.
B. The second method is to first measure the delay difference of the two sets of outdoor bluetooth speakers, and then find their phase difference, and finally, pull the phase curve of the auxiliary outdoor bluetooth speakers to be the same as the main PA outdoor bluetooth speaker.
From the operation method, we can conclude that the difference is only the difference in the sequence of adjustment steps, but for actual operation, the first type is easier to learn, because the phase curve at close range is relatively stable and easy to observe and judge. But if the two sets of outdoor bluetooth speakers have been hung higher, the operability of the scenario A method is relatively weak.
The above is for the debugging between outdoor bluetooth speakers of different manufacturers. Sonic will adjust the phase before shipment. For customers, the later processing will be more convenient.