Welcome toChina Electro-acoustic Net
Add to Favorites | Chinese
Understand professional acoustics index of commonly used function
From;    Author:Stand originally
Range of professional acoustics application is wider and wider, umbriferous period net reminds you: If you are firm contact acoustics, must want to understand basic function index so, this avoids by businessman flicker:

1) frequency is answered (effective frequency limits)
This index reflected the main frequency range that loudhailer works. Should try to loudhailer source of constant voltage signal arrives by low frequency when frequency of source of signal of high frequency change, the sound that loudhailer produces presses the change that follows frequency change. The sound that reachs from this is pressed -- frequency curve, the frequency that is loudhailer answers a curve. IEC (international Electrotechnical Committee) set loudhailer can bounds of replay audio frequency, namely effective frequency limits, be peak value is compared in taking loudhailer sound to press frequency character curve an around times frequency the frequency scope that average sound pressure level reduces 10dB. This range is wider, the character that put reputation is better
General high fidelity asks with loudhailer box lowest frequency noise is 50-12500HZ(4~-8dB) , can achieve 50-16000Hz enough already. Of course 30-20000Hz is better.

2) rated impedance
Its show loudhailer is in some is specific working frequency (intermediate frequency) when the impedance value that measures in input end. Indicate on product brand nameplate namely normally, give out by the manufacturer. The impedance of loudhailer is characteristic. The rated impedance that gives out by the manufacturer is in rated frequency limits is expected to get normally most the impedance model value of great merit. Rated impedance sets 4 Europe, 8 Europe, 16 Europe, 32 Europe to wait commonly, abroad also has use 3 Europe, 6 Europe to wait.

3) power
The power volume of loudhailer is one of main index that choose use loudhailer. Should point out home, outside the mark law of loudhailer has very big difference, because to power the definition explains each are not identical,this is. The power with nominal place is general loudhailer rated power.

Rated power or rated noise power, it is to show loudhailer can be long the power input when work continuously and producing unusual sound. Pink noise signal is used when general test, pass specific filter, the test has inside rated frequency limits. Press IEC standard, do not arise in the successive job that the loudhailer that be measured should assure to be in 100 hours unusual. Point out incidentally, american EIA standard stipulates experiment time is 8 hours, and filter is different also.
Power of the biggest noise and rated power are different, it is to show loudhailer bears the ability of the big power input of short time, its experiment time is a few seconds only or a few minutes. The 2-4 that power of general the biggest noise is rated power times.

4) sensitivity
Characteristic sensitivity is to point to increase the tension of pink noise signal that is equivalent to power of the 1W on rated impedance when sound box when, measures sound pressure level handles in axial 1m. The sensitivity of loudhailer box and efficiency are two different ideas, efficiency is output sound power and input electric power than, but the efficiency of the loudhailer case that popularly says sensitivity is tall is taller also.
Previous12 Next
About us | Legal Notices | Sitemap | Links | Partner