Questions tagged [audio]
Questions about designing electronics for measuring, processing, and amplifying audio signals.
3,466 questions
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Understanding an unusual combination of crossover diodes in a class AB amplifier
Another user had a question about distortion in an audio amplifier. The culprit seemed to be oscillations around Q2-Q4. Here it is again for reference:
Not having a lot of experience with class AB ...
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Is this the appropriate way to wire two dynamic mic capsules to an XLR connector? What polar pattern will this microphone have?
I have a Sony F-99S microphone, with two dynamic capsules facing opposite directions. It was originally wired in stereo, with two unbalanced outputs. I am thinking I'll combine them to get a figure-8 ...
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Distortion on negative slope of audio amplifier
I inherited this PCB, I guess it's a high voltage, class AB amplifier. This is supposed to be the replacement an older version. Here's what the circuit looks like:
The input signal looks clean, but ...
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DC offset on power amplifiers output
I have a couple of questions about the DC offset on the output of the power amplifier. Lately, I've been trying a couple of designs in LtSpice and I noticed that DC offset is much too high(or so I ...
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Is there a rote procedure for testing a transformer removed from its circuit other than checking its windings' continuity and output voltages?
For context, I'm repairing an old JVC CD player stereo unit with a polarized plug, hence the onboard transformer. Also, hence the absence of a service manual of any kind.
It attempts to turn on upon ...
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Metronome circuit with NPN collector tied to PNP base
I'm self-learning about transistors. This circuit is from p 104 in Getting Started in Electronics by Forest M Mims III. Unfortunately he provides no explanation (most of the book is like this).
Here ...
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Output impedance of a simple BJT current source
At the beginning, I wanted to say that English is not my first language, so I'm sorry for that. Also, it's probably a very stupid question, but I just want to know.
Lately, I've been trying to learn ...
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Analogue audio to USB [closed]
I need to send analogue audio into a mobile phone, preferably using a USB cable.
I have connected the audio output to the mic input on an ordinary analogue-to-USB converter for 3.5mm TRRS headsets, ...
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Microphone Analog Beamforming Circuit Questions
Summary
I've designed a beamforming circuit that uses two electret condenser microphones (ECMs) in a differential end-fire array and outputs to a bluetooth module's ADC for transmission.
I explain my ...
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Theory of dual 555 timer warbler circuit
http://electronic-projects.50webs.com/555-based-siren-circuit.htm the source online, but who knows the original designer.
U2 is configured to have a much higher frequency than U1. U2 provides the ...
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Diagnosing fault with latching NAND power circuit
I am trying to fix a vintage car radio, I have isolated the problem back to the power and buzzer daughterboard. The power button does not turn the radio on. The power button goes from OL to ~300 Ohms ...
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Second order High Pass Shelving Filter using op-amp for audio
I am looking for op-amp based second order high pass shelving filter whose corner is set at 25Hz and by 18Hz it should be 15dB to 18dB down. Thats quite a steep roll-off. While there are other filters ...
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Using a digital potentiometer compared to 'real resistors' for variable gain audio amplifier
I have the following circuit, where I am using a 100k digital potentiometer (DS1267B) to control the gain of an incoming audio signal.
In an attempt to minimize the load on the input, I pass the ...
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Causes of TL084 op-amp heating in a circuit that otherwise works normally?
This circuit is a DIY vocoder, built from a PCB. Design is based on a commercial product from the 1980s, the Syntovox 222.
original schematic
simplified schematic
The unit works normally but the quad ...
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Design a SPL meter
First of all, let me describe what I want to achieve:
Design an SPL meter with a measurement range from 30 dB to 130 dB (ideally up to 140 dB if possible).
Use an electret condenser microphone with ...
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