Questions tagged [audio]
Questions about designing electronics for measuring, processing, and amplifying audio signals.
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Audio amplifier for a physics experiment, how do I make it? [closed]
The experiment includes a mic taking in sound(2KHz-4KHz) and sending it to a DSO. I need an audio amplifier circuit in between that to amplify the signal so it would be visible properly. The ...
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Coupling/decoupling power supplies: how? [closed]
I'm adding a hi-Z adapter to a solid-state amplifier that is powered from the mains through a transformer and regulator. The hi-Z adapter is powered by 24 volts DC, so i need an external power supply ...
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Audio Codec Input/Output Channel Stages
I am planning to build a PCB for a Eurorack Modular Synthesizer, incorporating an STM32 for DSP and a bidirectional Audio Codec like the TLV320AIC3104 to handle the ADC/DAC.
Eurorack audio signals ...
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How can I record with this old fashioned mono microphone? [closed]
I have this microphone that comes with a 3.5mm mono jack connector.
When I plug it in to my laptop or my phone it won't work, and I believe the "mono" part is the problem. What do I need to ...
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How do you choose an audio isolation transformer for a microphone?
I found a few SE Q/A's for audio transformer characterization, but they neither address calculating the impedance match, nor consider signal loss for weak audio sources (like those from a microphone).
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Do audio impedance mismatches cause reflection (ie, 8-Ohm output to 20kOhm input) ? Does it matter?
I understand that audio source⇒input impedance mismatches are normal, and this answer provides a good reason as to why. However, having worked with RF more than audio, mismatches cause reflection that ...
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Why does 9.7Vrms == 27 Vpp? I thought it was 9.7/0.707 == 13.72!
At first, I thought this calculator was wrong, because I have always used an RMS to peak-to-peak conversion as \$ V_{RMS} = \frac{V_{pp}\sqrt{2}}{2}\$:
https://benchmarkmedia.com/blogs/calculators/...
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What type of cap would you use to block DC on a microphone-level audio line (unbalanced)?
I need to block a DC voltage on a microphone line, and a bit of research shows that MLCC is a bad idea because they can mechanically ring from vibration.
Question:
What type(s) of capacitor could be ...
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What is the maximum dBu I can send into a microphone input in this schematic?
The schematic below is from the Icom 9700 radio service manual (page 80). I would like to feed this input from a mixer board's ALT-3/4 outputs, and I want to avoid blowing the TS462 microphone preamp ...
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Bipolar 15 V DC from 9 V DC
I’m looking to get a regulated ±15 V DC @100mA minimum from a 9 V DC source. It’s for an audio circuit, so it needs to have a switching frequency well above audio range, and it needs to have a small ...
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How can I make an adapter wiring for a TRRS microphone to TRS?
I'm making a sound level meter using a Raspberry Pi as part of my thesis. My professor has given me a TRRS microphone to work with.
I tried to make the TRRS microphone work with the Raspberry Pi ...
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What is the reason for using decibels to measure sound?
If the decibel represents a gain ratio, why do we use it in sound measurements?
Yes, since we have an input signal in audio amplifier circuits, we can understand the behavior of this system according ...
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Measuring voltage from the aux cable signal
I wanted to make a bjt amplifier circuit to get used to analog circuit design. My plan was to use an AUX cable connected to my phone. I cut the cable and stripped the 3 wires inside. I wanted to see ...
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What is the function of the inductor in this Bluetooth audio module?
I found the circuit below for a Bluetooth sudio module that included a 100 mH inductor in series and then a 10 uF capacitor in parallel to the power input.
Image source: Iranian electronics seller ...
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Looking for feedback on audio schematic [closed]
I'm making an mp3 player and I'm looking for feedback on the audio side. It takes an i2s input from an esp32(not in this sheet), and outputs to a headphone jack. This is my first audio project (...
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Audio project converting TSH-4 headset to 3.5 mm audio jack
I've been trying to connect this TSH4 headset to a 3.5 mm audio jack. The headset has kind of a weird setup, with Mono audio + and - being the top pins (I don't know which is which, but the polarity ...
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Making audio signals imitate USB flash drives [closed]
If there is a USB port designed for USB flash drives that plays the audio files in that drive when it is connected --such as the ones commonly found in cars-- is there any practical way to turn an ...
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Modifying TI schematic to learn more about amplifiers
Let me start off by saying that I'm a complete beginner. I've watched some videos on amplifiers and read about them but it's hard for me to analyze circuits that don't match exactly to the examples I ...
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Audio engineering: amplifying two different sources
I've started a small project to renovate/rebuild an old record player for my wife. I have a degree in Electrical Engineering, but it's been almost 15 years since I last had to project/build a circuit, ...
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Can an audio isolation transformer between a preamplifier and an amplifier cause the amplifier's fuse to blow? [closed]
I'm building a microphone preamplifier. I was having problems with hum (intermittent ground hum when touching the case) and decided to try adding an audio isolation transformer (600 ohm : 600 ohm) ...
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Inline volume control for analog audio signals with push buttons [closed]
I want to build something to control the amplitude of analog audio signals between the source (line level analog audio output already extracted and decoded from an HDMI source) and the AMPs. In ...
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PCB digital sound input and output
I've designed a simple 3-band equalizer circuit. I've used 3.5 mm audio input connected with computer via 3.5 mm audio jack for input, and basic small speaker for output.
In all my references, many ...
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Audio amplifier for school project
For a school project, we have to explain this design of a audio amplifier. We have only been able to understand to parts marked with colored rectangles.
The design comes from the book audio power ...
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Identify and substitute f1404zs
I need help understanding which chip I need to buy.
First, I hope this is the correct community; if not, I apologize.
My intention is to repair a Mark Levinson 86280-0w690 audio amplifier, inside ...
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How to generate a 50-100 Hz 12 Vac sine wave for audio tone from 5 VDC (PB0 pin) atmega164p microcontroller [closed]
I have programmed to ATmega 164P to make PBO high when PC1 is low. In programming, I'm adding other peripherals as well.
But I am facing one issue regarding generating a tone. I have drawn low pass ...
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How to replace microjack on stereo earplugs with microphone [closed]
I broke a microjack connector. It is attached to a set of stereo earplugs with built in microphone. I know how to solder, but I am not sure how to find the correct replacement plug and how to identify ...
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Boost or buck audio input to minimum and maximum levels
Similar to Simple circuit to boost line-level audio
Background:
Some songs start out really quiet - Queen is notorious for this - and then eventually ramp up to passable audio levels. To hear them, ...
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How does one add a volume control to this circuit?
My uneducated guess is to add a potentiometer at R6. Can anyone confirm?
Image courtesy : amplifiercircuit.net
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How to modify frequency of an analog signal [closed]
I want to create my own pcb. First step is to design my circuit. I thought about a voice modifier.
So, in the breadboard I should put:
a microphone (an electrostatic electret microphone)
followed by ...
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switchable summing audio mixer volume troubles
Consider this audio mixer. There are 3 sources that may play any kind of audio (the sine generators are just illustrative). You can switch any of them to either of 2 outputs using the SPDT switches.
I ...
