Filter for Audio Limiter
for DVD
Published in issue 312, July 2002
In the ‘Audio Limiter (for DVD)’ circuit, the peak values of the audio signals are used to reduce the dynamic range of the sound. A possible disadvantage is that the entire audio spectrum is used to determine the level, so that peak levels in the low or high frequencies may lead to suppression of, for example, voices in the mid frequency range. If we divide the spectrum into three ranges and for each range a separate window comparator defines the signal level then the signals in one range will have a smaller influence on the other two ranges.
Resistors: R1,R2,R13,R14 = 46kOhm 4 R3,R15 = 45kOhm 3 R4,R16 = 73kOhm 2 R5,R17 = 28kOhm 7 R6,R18 = 499kOhm R7,R19 = 34kOhm 0 R8,R20 = 13kOhm 3 R9,R21 = 232kOhm R10,R22 = 8kOhm 25 R11,R23 = 8kOhm 06 R12,R24 = 7kOhm 87 Capacitors: C1,C13 = 15nF C2,C14 = 39nF C3,C15 = 2nF2 C4...C6,C12,C16,C17,C18,C24 = 1nF C7,C8,C9,C19,C20,C21 = 27nF C10,C22 = 6nF8 C11,C23 = 18nF C25-C31 = 100nF Semiconductors: IC1,IC2 = TL084 IC3,IC4,IC5 = LM339 Miscellaneous: K1 = 14-way DIL connector (2 off) 14-way flatcable
|
Click below to download a PDF copy of this article from Elektor magazine.
Please note. In view of the complexity of international markets, Elektor cannot guarantee the availability of components for this project.
|