You can clearly see that the frequency spectrum of the original, unclipped waveform is clean and goes to zero outside the bandwidth (bottom left), whereas in the clipped signal, there is a general minor distortion of the spectrum (expected if clipped) and most importantly, higher harmonics/spikes/non-zero contributions in the spectrum outside the bandwidth of the signal (bottom right). Here, I create a bandlimited signal of 1s duration, sampled at 1000Hz, and then clip it to between ☐.8 (see the top plot in the figure below) time = 0:0.001:1 ĬleanSignal = sin(2*pi*75*time).*chirp(time,50,1,200) ĬlippedSignal = min(abs(cleanSignal),0.8).*sign(cleanSignal) Here's a short example in MATLAB demonstrating this. If your signal is bandlimited (most real world signals are) and you're sampling well above the Nyquist rate, then this stands out quite clear as day. This introduces higher harmonics in the frequency spectrum which would not have been there originally. Recall that when a signal gets clipped at some threshold, it locally resembles a square wave in the clipped regions. However, a more robust solution is to analyze the frequency spectrum of the recording. Do not increase the input sensitivity of any amplifier as this will defeat the purpose of this procedure by permitting excessive clipping (distortion).The simplest answer if you're dealing with short recordings is to listen to it and detect "pops" (short spiked sound) in the playback. This is accomplished by listening to the system at a moderate level and turning down the input sensitivity controls of amplifiers that are playing too loudly. ![]() Reconnect all the speakers, turn the head unit on and proceed to adjust the level balance between the subwoofer and satellite amplifiers. Once you have adjusted each amp to its maximum unclipped output level, turn down the volume of the head unit and turn it off. ![]() If the “Clipping” indicator is lit with the “Input Sensitivity” control turned all the way down, set the “Input Voltage” switch to the “High” position, then slowly increase the “Input Sensitivity” control until the “Clipping” Indicator is solidly lit
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |