Quest Engineering Q-Tech QTA1120P, Руководство пользователя

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QTA- 1120P/1240P
User Manual
User Manual Q-Tech Commercial Series
QTA-1120P/1240P
8
Output Impedance Output Impedance Output Impedance
0.1W 100K
Ω
10W 1K
Ω
40W 250
Ω
0.5W 20K Ω 15W 667 Ω 50W 200 Ω
1W 10K
Ω
20W 500
Ω
75W 133
Ω
2W 5K Ω 25W 400 Ω 100W 100 Ω
3W 3.33K
Ω
30W 333
Ω
150W 66.7
Ω
5W 2K Ω 35W 286 Ω 200W 50 Ω
(100V plan) P = E x E / Z = 100x100 / Z = 10,000 / Z
P: Power(W), Z : Impedance (
Ω ), E : 100V(Designed voltage of a general-use amplifier)
High impedance of speakers and output calculation table for 100Volt systems
For the benefit of those who want to calculate
the power of the system with a formula. See
below:
Determining power by calculating
total impedance
The alternative to counting the speaker taping
watts is to calculate the total impedance of
the line, which will also indicate the wattage
necessary to drive the system correctly.
The computational formula is voltage squared
divided by impedance:
Power = Voltage2 / Impedance .
When the speaker line reaches its top voltage
of 70 Volts, the formula is:
Power = 5000 / Impedance (because 70
squared equals 5000).
To measure impedance a dedicated meter is
required. These use a 1k frequency to send an
alternating current through the transformer(s).
The resulting figure indicated by the meter’s
dial can be cross referenced with the meter’s
impedance chart to see what value should be
expected and the power that will be required.