First, look at the unit size and frequency division point of the speaker.
It is ready to judge a lot of information, such as high if it is to use 44 mm diameter of the high, the working frequency of safety not less than 2 K, if the tenor is to use 4 6 inch and a half, you can determine the design is unreasonable, because 2 minimum horizontal spacing should be 6 and a half inches more than 7 inches, 7 inches of interference in low frequency is around 1.34 K formula (242), so for the sake of the safety of the unit, frequency division point in 2 K, alto in 1.34 K interference occurs, in order not to interference, crossover point at 1.3 K, 44 treble diaphragm was soon to break out. So it's completely irrational.
Look at the impedance curve.
Bass, in particular, if the design is not reasonable speakers, impedance curve soon, according to the unit T/S parameters design reasonable speakers, low-frequency characteristics not bad, if see volume on impedance curve is not enough, or is tuned on the low side, or is tuned on the high side, or there is a resonance, or excessively large volume, low frequency is not good. Speaker impedance curve is bad, often the designer's theoretical knowledge is not enough, the speaker factory in guangdong, the stronghold in the Chinese speakers is difficult to break into the European and American market, one reason is that almost no original design, there are a lot of people spend a lot of time doing by trial and error in the original method in speaker, with a scientific method to design professional speaker factory are rare, this is the industry's sorrow!
Talk to developers.
Before listening to the speaker, if the speaker r&d staff can not find out the factory for communication, it is usually the COPY product. If the developers themselves can't explain his design ideas, the speakers aren't much better. Speaker structure, how to determine the frequency division point, the selection of each unit size and the dynamic margin of the whole speaker relationship.
Whether the mobile system matching is considered.
Many of the line array speakers are used for mobile performance, if the line array pendant, weight, handle design did not consider the rapid installation, the use of reality will not meet the requirements of performance. Matching system cabinet whether the operation is simple, small volume, light weight, the inside of the cabinet wiring and power supply are all connections, is there a special interface in cabinet positive convenient connection, the processor is there a standard preset program inside, if send all frequency to cabinet is OK, all frequency and low have independent input.
To have the cover of form a complete set, have the horn line of form a complete set, the design of the hanger is reasonable security do (7:1 safety coefficient, tensile experiment), whether can be single point hanging adjustable array with porous beam (middle) of the vertical Angle, transport packaging is air box or the wheel plate, air box lock and wheel must use reliable solid materials (both parts) is the most easy to bad.
Whether the parameter curve of the final speaker is true.
Many factories have graphs, but are they true? If can be in after listening, direct test speaker is ideal frequency response and phase curve, it is best to separate unit test phase curve, if the treble, alto, bass separately measured curve of phase points in the frequency is not coincidence, that do the speaker processor parameter is unreasonable, frequency response near the crossover point also can not be normal. One curve was measured at the axis and 45 degrees off-axis (also 4 meters) 4 meters away from the line array of more than 4, and the difference between the two curves was observed. In the frequency band of 700-12k, the two curves were just evenly different by about 6DB, indicating that the horizontal coverage of the line array was 90 degrees, and the directivity was very good. The microphone is placed on an axis over 50 meters to measure the frequency response, and the high frequency is still flat up to 13K, which means the high frequency of the speaker is good. At 80 meters it's still flat up to 12K which means it's a good speaker. Has the unit done any AES power experiment? If the r&d personnel cannot even say what the AES power experiment method is, they certainly have not done any power experiment, so the actual power of this speaker is questionable.