Hello, hello..
I uploaded a schematic from LTspice for an LM386 electric guitar amp and its frequency response.
Can someone help me about whats going on with the input filters and output filters?
NOTE: The LM386 has an internal 50K resistor to ground to set the impendance.
So, i added, after the MPF102, a 33K resistor (R4) and a 0.69nF cap (C2) that form a low pass filter with frequency response corner at about 7kHz. After, the 100K resistor (R1) is in parallel with the LM386s' internal resistance giving a total resistance of about 33K. This resistance combination with the 0.1uF cap form a high pass filter, with corner frequency at about 48Hz.
FInally, the output coupling cap (C3) form a high pass filter with the speakers impendance giving a frequency corner at about 90Hz.
Is these right? Or am I missing something?
Because LTspice is giving me other values than these. The overall frequency response is calculated by LTspice at 370Hz and 15kHz.
Cheers everyone!
I uploaded a schematic from LTspice for an LM386 electric guitar amp and its frequency response.
Can someone help me about whats going on with the input filters and output filters?
NOTE: The LM386 has an internal 50K resistor to ground to set the impendance.
So, i added, after the MPF102, a 33K resistor (R4) and a 0.69nF cap (C2) that form a low pass filter with frequency response corner at about 7kHz. After, the 100K resistor (R1) is in parallel with the LM386s' internal resistance giving a total resistance of about 33K. This resistance combination with the 0.1uF cap form a high pass filter, with corner frequency at about 48Hz.
FInally, the output coupling cap (C3) form a high pass filter with the speakers impendance giving a frequency corner at about 90Hz.
Is these right? Or am I missing something?
Because LTspice is giving me other values than these. The overall frequency response is calculated by LTspice at 370Hz and 15kHz.
Cheers everyone!
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