All Questions
107
questions
0
votes
2
answers
55
views
Can the impedance of the source affect the response of a high-pass filter?
Having a simple RC high-pass filter, can a high signal impedance change the cutoff frequency response? Or more practically, should a resistor before the capacitor be included in the calculation for ...
- 53
1
vote
2
answers
121
views
RC or RL high pass audio filter?
Some bass guitars from the 60s, namely Gibson and Guild, used RL, LC, or RLC high pass filters to reduce bass frequencies if desired. The control for these switches was commonly referred to as the &...
- 13
0
votes
3
answers
136
views
What are these resistors and capacitors doing in this audio CODEC circuit?
I'm implementing the VS1053 Audio CODEC IC on a PCB design where I will be using it along with a class D amplifier that will connect to a pair of 8 ohm speakers. I'm looking at SparkFun's MP3 Player ...
- 1,195
2
votes
1
answer
109
views
Placement of filter capacitors in a circuit with multiple audio outputs
I have a multiple output stage of an audio circuit as in the picture attached.
I want to add a capacitor to eventually filter any DC at the output, therefore I placed a RC filter 10uF/100k(0,16 HZ) ...
- 53
2
votes
1
answer
104
views
Can the differential output signal of a DAC be AC coupled directly to the differential input pins of a class D audio amplifier?
The datasheet of the audio codec I'm using (CS4272-CZZ) suggest a filter on the differential output pins. Their suggested configuration also combines the signals into a single ended output. I want to ...
- 45
0
votes
0
answers
75
views
Fine-Tuning a Circuit After changing VCA (SSM2641 to SSI2164)
A friend's accident led to a fried SSM2641 VCA in an Eurorack audio module. Determined to give it a new lease on life, I'm diving in, though VCAs are not my forte.
After searching for hours, it seems ...
0
votes
4
answers
154
views
Analysis of an RCL Filter Utilizing a Potentiometer as R
I am trying to calculate the parameters ζ, Q, Fo, Gain (dB), and BW of this circuit. I am confident in the following equations:
Fo = 1 / (2 * π * √(L2 * C1)) ; Q = 1 / (2 * ζ) ; BW = Fo / Q
R2 = R5; ...
3
votes
1
answer
249
views
Using the same ultrasonic transducer for Tx and Rx in distance measurement
Goal:
Measure distance to surrounding objects using 5 automotive grade
ultrasonic transducers mounted to different points on a small robot.
Requirements:
Multiplex the drive and receive pulses so ...
- 31
0
votes
0
answers
108
views
Variable rc high pass filter
Hey there I’m new in this field please guide me as much as you willing to. Recently I’ve build the 3rd order high pass filter with RC circuit using a selector switch to send the audio signal to ...
- 1
0
votes
0
answers
80
views
Inductor type: LR Low-pass filter
Is it a common practice to use unshielded inductors for LR networks in audio applications?
I need to include a 1st order LPF for the output of a DAC. I found many inexpensive unshielded 10mH inductors ...
- 109
1
vote
0
answers
64
views
Best way to implement bypass circuitry for analog crossover filter circuit?
Below is a system block diagram of a schematic / PCB I am working on. It is an SOC with two differential audio DACs (left and right audio channel). Each channel has a fully differential cross-over ...
- 115
2
votes
2
answers
966
views
Is the cut-off frequency of a 4th-order filter at -12 dB or -6 dB?
I designed a 4th-order active Linkwitz-Riley crossover filter by cascading two 2nd-order Linkwitz-Riley filters.
Below are the simulation results. The red and purple waveforms are taken at the output ...
- 115
3
votes
1
answer
236
views
Why am I measuring such high THD+N on my active high-pass filter?
I have designed a 2nd-order active Sallen-Key high-pass filter for use in an audio circuit. An LTspice schematic is shown below, where VDD is 5 V.
I have also breadboarded the circuit using low ...
- 115
1
vote
1
answer
124
views
2nd-order Butterworth for an 8 Ω tweeter
I want to cross it at 4600 Hz and want it to drop off faster than a first-order filter.
I used two different crossover calculators. Why is there a 0.39 mH inductor across the tweeter's positive and ...
- 21
1
vote
2
answers
356
views
Twin-T notch filter with high input impedance and low output impedance using one op-amp
I have a very space and power constrained application, where I want to apply a twin-T notch filtering to an audio signal and add a little gain of about ~10x.
The following filter section has the ...
- 22.5k