25
It is always advisable that use 1% resistors, since if use 5% resistors, the gain has
more variation with regard to the table.
You should be careful with the high gains adjustment (higher than 6 dB), since the
crossover dynamic decreases considerably.
FILTER FREQUENCY CALCULATION:
There are two resistors in the equalizer card called RF and RF,' that configure the
center frequency of the equalization point. These two resistors should be equal: RF= RF.'
The next table shows the resistors that should use for the thirty frequencies ISO stan-
dard. If you want an intermediate frequency, are able to calculate an intermediate value:
FREQUENCY
5% RESISTORS
1% RESISTORS
25 Hz.
2 M
1,91 M
31,5 Hz.
1,5 M
1,54 M
40 Hz.
1,2 M
1,21 M
50 Hz.
910 K
953 K
63 Hz.
750 K
768 K
80 Hz.
620 K
604 K
100 Hz.
470 K
487 K
125 Hz.
390 K
383 K
160 Hz.
300 K
301 K
200 Hz.
240 K
243 K
250 Hz.
200 K
191 K
315 Hz.
150 K
154 K
400 Hz.
120 K
121 K
500 Hz.
91 K
95,3 K
630 Hz.
75 K
76,8 K
800 Hx.
62 K
60,4 K
1 KHz.
47 K
48,7 K
1,25 KHz.
39 K
38,3 K
1,6 KHz.
30 K
30,1 K
2 KHz.
24 K
24,3 K
2,5 KHz.
20 K
19,1 K
3,1 KHz.
16 K
15,4 K
4 KHz.
12 K
12,1 K
5 KHz.
10 K
9,76 K
6,3 KHz.
7,5 K
7,68 K
8 KHz.
6,2 K
6,04 K
10 KHz.
4,7 K
4,87 K
12,5 KHz.
3,9 K
3,83 K
16 KHz.
3 K
3,01 K
20 KHz.
2,4 K
2,43 K
