Appendix a (signal to power) – Proel PC260 User Manual
Page 35
35
Appendix A (signal to power)
With the following table is possible to set the limiters without using a scientific calculator . To explain how to use it we make an
example .
You have two loudspeaker with this data:
Power handling: 250 Waes
Nominal Impedance: 8 ohm
and an amplifier capable of 600 Wcontinuos at 4 ohm with a FIXED GAIN of 32 dB, so
the loudspeakers are arranged in parallel resulting a power handling of 500 Waes at 4 ohm,
you have to choose the 4 ohm column in the fixed gain = 32 dB, scroll the values until reach 475, it is the value more close and slighlty
less to 500 Waes, then scroll the row at right and note the +3 dBu value, this is the value of the input signal that delivers 475 W to your
loudspeaker, you have to set the limiter to this value .
Note: to avoid clipping the amplifier must be always capable to deliver a power greater than the power you have to limit .
dBu
dBv
Vrms
2 ohm
4 ohm
8 ohm
16 ohm
2 ohm
4 ohm
8 ohm
16 ohm
+21
+18,79
8,696
7526
3763
1881
7490
+20
+17,79
7,750
5978
2989
1494
5950
+19
+16,79
6,907
9497
4748
2374
1187
9452
4726
+18
+15,79
6,156
7544
3772
1886
943
15016
7508
3754
+17
+14,79
5,487
5992
2996
1498
749
11927
5964
2982
+16
+13,79
4,890
4760
2380
1190
595
9474
4737
2369
+15
+12,79
4,358
3781
1890
945
473
7526
3763
1881
+14
+11,79
3,884
3003
1502
751
375
5978
2989
1494
+13
+10,79
3,462
2385
1193
596
298
9497
4748
2374
1187
+12
+9,79
3,085
1895
947
474
237
7544
3772
1886
943
+11
+8,79
2,750
1505
753
376
188
5992
2996
1498
749
+10
+7,79
2,451
1196
598
299
149
4760
2380
1190
595
+9
+6,79
2,184
950
475
237
119
3781
1890
945
473
+8
+5,79
1,947
754
377
189
94
3003
1502
751
375
+7
+4,79
1,735
599
300
150
75
2385
1193
596
298
+6
+3,79
1,546
476
238
119
59
1895
947
474
237
+5
+2,79
1,378
378
189
95
47
1505
753
376
188
+4
+1,79
1,228
300
150
75
38
1196
598
299
149
+3
+0,79
1,095
239
119
60
30
950
475
237
119
+2
‐0,21
0,976
189
95
47
24
754
377
189
94
+1
‐1,21
0,870
151
75
38
19
599
300
150
75
+0
‐2,21
0,775
120
60
30
15
476
238
119
59
‐1
‐3,21
0,691
95
47
24
12
378
189
95
47
‐2
‐4,21
0,616
75
38
19
9
300
150
75
38
‐3
‐5,21
0,549
60
30
15
7
239
119
60
30
‐4
‐6,21
0,489
48
24
12
6
189
95
47
24
‐5
‐7,21
0,436
38
19
9
5
151
75
38
19
‐6
‐8,21
0,388
30
15
8
4
120
60
30
15
INPUT SIGNAL to OUTPUT POWER CONVERSION TABLE
Input Signal
Signal references
Power Output
Fixed amp gain = 26 dB
Impedance
Impedance
Fixed amp gain = 32 dB