Questions tagged [digital-audio]
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77 questions
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VBUS Filtering for USB-Powered Audio System with Pi Filter
I'm designing an audio system powered by a USB 2.0 connector (5V, 500mA). The system is shown below:
The filtered +5V VBUS power line drives the DAC, LP filter, and audio amplifier. To filter the ...
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Music player via ESP32
I have a music player via an ESP32 and an SD card module
Structure:
SD card module (with the .wav files) -> ESP32
ESP32 pin 26 to Audio amplifier module LM386 IN (with 10µF capacitor between IN and ...
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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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Why is there a greater lag in Bluetooth headphones compared to wired?
The Usual Answers and Responses:
Encoding, Compression, and Buffering
The typical answer to this on the internet is because Bluetooth headphones require the conversion of one form of data information ...
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STM32F7: How to store one cycle of sinewave (1kHz) in array as PCM data?
I'm using a STM32F746 discovery board to learn about digital audio. I'm doing the basics right now. I want to store a single cycle of a 1kHz sinewave in an array and eventually use a DMA to transfer ...
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Designing support for BT in a car's audio system
We are designing a pre-amplifier outputting I2S and need to stream this to a car's audio system via Bluetooth. We have tried a module from TinySine, but it turned out it can only connect to headphones....
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TDM signal conditioning
I'm looking to transmit TDM signals (digital audio) over long-distance cables (around 5 meters). I did some tests with an oscilloscope and the signal is getting too much distortion. I was wondering if ...
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Is it possible to add headphones to a Geiger counter circuit?
The main problem is as follows. From what it seems, most Geiger counter circuits opt for a piezo clicker. I'd like to just plug in a 3.5mm audio jack and be able to hear when pulses come in. The ...
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Calculating audio sample output rate for synthesizer
I'm building a synthesizer on an FPGA and I'm having trouble calculating sampling rates. Currently, I'm running a system clock at 98.3 MHz and I want to produce 16-bit audio at the output.
I've got a ...
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Reason for the degraded I2S signal
I'm working with one of the devices from the NXP's IMX family - the IMX93 evaluation board.
I've managed to setup the sound card drivers already, the next step was to test I2S signals output via the ...
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How to receive digital audio via polling the SAI?
I'm trying to receive digital audio on an STM32 by polling the SAI, via HAL_SAI_Receive. Eventually I will switch to DMA; my goal now, though, is to simply be able ...
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What is SAI frame synchro?
The SAI interface, as used by ST and others, includes some options which I have not been able to find any explanation of. Justme's answer provides a great explanation of frame, slot, and data size; I'...
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Can I capture audio over SPI on from the onboard MEMS microphone?
I have a STM32H735G-DK Discovery board and would like to record audio from the onboard digital MEMS microphone, a MP34DT01TR-M which provides PDM audio.
It would seem to me the simplest way to do ...
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Regular DACs versus audio DACs
Context
In trying to make modular linear power supply with digital control, I figured I'd need a DAC to output the correct voltages into the feedback circuitry (two - one for voltage and one for max ...
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USB Audio interface, voltage regulator failed, what happens to the connected circuitry?
I tried to build an open-source (and unfortunately not longer maintained) USB Audio interface (https://github.com/freeDSP/freeDSP-INFINITAS).
The project is built around a XMOS chip XE216-512 and a ...
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What's the relationship among speaker amp IC's supply voltage and gain?
I am new to designing audio circuit. Looking at TI TAS6424 class-D amplifier (https://www.ti.com/lit/gpn/tas6424-q1), on section 9.3.3 p.23, it mentioned volume control from -100 to +24 dB.
Given the ...
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How long is the S/PDIF preamble?
I have a simple S/PDIF protocol question that I can't find the answer to anywhere. I'm trying to understand the protocol, and everywhere I look says the same thing: The length of a preamble pattern is ...
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Unexpected DAC output waveform when connected to a line input
I'm using a TAS5754MDCAR DAC in a Bluetooth receiver. DAC_OUTA and DAC_OUTB are connected to the internal amplifier inputs per the Datasheet (as below):
When I play an audio file and view DAC_OUT on ...
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349
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Can I connect multiple different devices via a single I2S interface?
I am using a microcontroller with only one I2S interface. I am using MAX98357A which has 1 sound chip. There is 1 microphone, SPH0645. Can I connect these ICs to the same line provided that I cannot ...
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RN52 Custom Circuit Board Generating a Loud Buzz While Playing Audio
I'm in the process of creating a custom circuit board using an RN52 with a PIC16 controller to hack into my car's stereo and pretend to be a CD changer. The device does work, but while the audio plays ...
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I need clarification for an audio power amplifier circuit component
Below is the block diagram of my first design using an audio power amplifier.
The input to the audio power amplifier comes from an SC200 module by Quectel.
The output of the PA is connected to a ...
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Record audio with digital I2S MEMS microphone and store audio as wav file on PC
I would like to use a digital I2S microphone to record audio and store it as wav on a PC, preferably over serial connection. I have tried this with the boards ESP32 dev kit v1, MKR Wifi 1010 and ...
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Recording aliased tones on purpose
For research purposes, I am trying to transmit a tone and record it using sub-Nyquist sampling. Via the PC microphone, for instance, I would expect to see the aliasing effect somewhere in the ...
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How to interpret this PCM audio data?
I am attempting to write a program to get an ATmega328P to play audio. I first tried to use this library but I could not get it to work so I am now attempting to program my own. The problem is that I ...
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CD player playing digital noise on a track full of silence
I'm trying to repair a Nakamichi CD Player 3 that I got recently. Service manual from ElektroTanya
Relevant section of the schematic:
Initially, it would not open and just show an error. Replacing ...
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Understanding how a digital microphone's output gets stored in DSP memory
I am working with a DSP that takes audio input from a digital microphone. For the sake of this discussion all input sounds are pure sinewaves.
The DSP receives microphone data as 24-bit numbers. Let's ...
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742
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Trying to understand description of aptX Lossless audio streaming codec bitrate
I was looking at this article about the aptX Lossless audio codec.
The article claims that this iteration of the aptX codec can stream CD quality audio losslessly. At the beginning of the article, it ...
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Sample Rate Converter
I'm a novice when it comes to digital audio. What's the best way to convert 48 kHz I2S to 44.1 kHz? I have found the Texas Instruments SRC4392 but I do not believe that it will work for this ...
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What do I have to transmit to get digital audio out of a PCIe lane?
I want to get audio out of the PCIe lane and I can't find any chip made solely for this purpose (if you have a suggestion please tell me).
I took it upon myself to design and build it, but I don't ...
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Can I transmit audio sampled with I2S driver from ESP32 using Si24R1 (Chinese clone of nRF24L01)?
I'm trying to transmit audio via nRF24 with an ESP32 development board using a driver library from nopnop2002. I'm using the i2s-adc esp-idf lib functions to get data from an analog microphone and I ...
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Digital radio to Bluetooth bridge
I'm studying the possibility of building a bridge from DAB+ (digital radio) towards Bluetooth. The reason is that all the good quality DAB+ tuners are really expensive and the cheap ones usually have ...
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How different can the digital signal from a low-cost CD player be from that of an expensive Hi-Fi CD player?
According to the high-end Hi-Fi connoisseurs' bibles, for a perfect reproduction of the sound, in addition to "special cables", etc., you must have a specialized stage of CD which reads the ...
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Audio frequency response over Bluetooth
Introduction :
Using some binaural beat meditation, the vendor claims that their sound frequency goes down to 5 Hz to get better meditation quality. Even though the human ear can't hear 5Hz, the brain ...
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A way to make simple digital potentiometer [closed]
I am making a project which has an audio application with a TDA amplifier.
To change the volume I have a potentiometer on the input of the amplifier so when you change its value the sound is higher or ...
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If I invert an I2S data line, it inverts the audio, right?
It seemed obvious to me, but then I read all these audio forums where they're talking about overflow, tones, etc. and I just want to make sure I'm not missing something.
If you take an I2S signal:
...
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Is Bluetooth a bottleneck for audio quality when using a headset?
Context - My hearing impaired friend cant hear me well when I use a Bluetooth headset
A close friend and I enjoy talking on the phone while commuting. Unfortunately his hearing has gotten worse (...
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Is an AK4588VQ decoder able to pass PCM digital audio with its ADC digital interface?
I want to interface an AK4588VQ with only at maximum 5 wires. Is it possible? My system uses an STM32F746NG and requires two digital microphones (I2S) and one DAC. I've used this chip because I have ...
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My speaker connected to my TV is making weird noises only when playing videos [closed]
Apologies if this is the incorrect forum, if anyone knows of a better forum to ask on I would appreciate the redirection.
I have a very specific issue regarding audio playback from my TV. I have a ...
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Can I have a microcontroller with one I²S module as digital signal processor?
I was not very sure what title I should use, but the idea is: We have a Bluetooth module (BM64) and a DAC (PCM5122.) We want to put the microcontroller (STM32 Nucleo-F303K8) in between for digital ...
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How to remove low-level audio noise from an ATMEGA328p + LM386 circuit
I'm building an audio project with an ATMEGA328p using an LM386 as the amplifier and the Mozzi audio library.
Power source is 4 AA batteries.
I'm using an MCP1700 voltage regulator to drop the ...
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Best way to output n digital signals using n-1 DAC channels
I have 3 digital signals that need to be mixed and output into the analog domain. My DAC has 2 channels (Left and Right).
The way I see it, I can:
mix the signals 1, 2, and 3 digitally and output ...
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Get AES/EBU signal from S/Pdif
Recently on the road with an Audio Engineer, I've heared that (Coaxial) S/PDIF and AES/EBU are quite similar and could be passively adapted, and said that these two signals are the same on the logic ...
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Multi channel I2S vs TDM
I need to receive 8 channels of 24 bits at 48KHz. So I have two possibilities to accomplish that: either using 4 I2S or TDM.
I would like to understand the difference in clock rates between I2S and ...
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Interfacing PCM3060 Audio Codec With STM32
I am using a STM32F4 MCU, currently prototyping on a Nucleo-F446RE. I have a PCM3060 audio CODEC to do the analog to digital conversion. I am attempting to use the I2S protocol in order to interface ...
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Understanding input/output in audio amplifier
As I was trying to refurbish my Sony STR-434BS, I choose to install a brand new audio amplifier IC, specifically the TDA8954 as main chip for it's power deliver (around 100 [W] in stereo mode) and ...
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DC filtering for digital audio amplifiers
I am working with digital amplifiers and from what I can see there is a DC blocking filter that is placed at the start of the signal chain.
Why is this DC filter placed at the start of the signal ...
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analog vs digital automatic level control
In an analog broadcast audio chain, an automatic gain control (AGC) or compressor is employed to maintain a nearly constant average audio level fed to the over-the-air transmitter.
In a digital audio ...
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Dependence of the PWM amplitude of the amplifier on the battery voltage
I'm going to use speaker connected to internal Class D amplifier in WM8998 in my PCB.
Power source of my PCB is Li-Pol battery with 3.2-4.1V range or external 4V adapter.
Audio codec speaker power ...
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What would be the best, cheapest, smallest way to power a Bluetooth bone conduction headset project?
Please, be forewarned, I'm an idiot when it comes to electronic builds. The last thing I soldered was a pick-up in a guitar kit I built, and the thing still isn't grounded right.
I'm trying to build a ...
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Would an LM7805 need a heatsink stepping down two stacked LiR2032/CR2032 (3.6V X2) batteries?
Okay, I'm terrible at anything electronic, especially when it comes to building from boards (think rudimentary understanding). I've built a few PC's in my day, but piecemeal, not from scratch. Keep ...
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