Impedance - what is it in the columns?

Impedance is the impedance of an electrical circuit of a resistor, capacitance, and inductance, which acts when an alternating current of high frequencies arrives at the input of this circuit. Depending on the values ​​of capacitance and inductance, the impedance of the circuit varies. At low frequencies, the active element (resistor) has a greater effect. At high frequencies - reactive elements (capacitances and inductances).

Column resistance, which parameter to choose

Acoustic systems consist mainly of power amplifiers, frequency cross-over filters and loudspeakers.

The bandwidth is 20-20 000 Hz. Power amplifiers are broadband and divided by frequency range.

1. Low frequency (20-300 Hz).
2. Mid-frequency (300-5000 Hz).
3. High-frequency (5 000-20 000 Hz) belong to the class 3 band.

2-way amplifiers have two LF-MF and HF frequencies.The input signal is distributed by filters on the frequency channels and fed to the appropriate amplifiers.

Radio amateurs to calculate separation filters need to know the input impedance on different frequency bands. For low frequencies, the loudspeaker resistance is 4 or 8 ohms. Impedance can be taken equal to about 10% of these values.

You can measure it by connecting an audio frequency generator tuned to the dividing frequency (not lower than 6 to Hz) through a resistor of 1 com to the loudspeaker. The ratio of the voltages on the resistor and loudspeaker will show the desired value. In the same way is the impedance of the high-frequency head.

Features of connecting speakers

Connection of several acoustic systems to a signal source is carried out in a serial, parallel and parallel-serial manner. Accordingly, the parameter of the speaker group is calculated according to Ohm’s Law. The labels and instructions of the speakers, headphones, indicate their resistance (4.8.16 ohms). If your speakers are not new, lost instruction manual or for another reason you do not know the resistance of the speakers, it can be measured with a multimeter. What it is? This is a special device for measuring this parameter.

Freeing the speakers in the speakers from the equipment, measure their resistance. The multimeter will show slightly lower values ​​of resistances close to the standard.