Questions tagged [digital-audio]
The digital-audio tag has no usage guidance.
77 questions
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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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6
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ESP32 ADC not good enough for audio/music?
I've heard that the ESP32's ADC isn't "good" enough for audio purposes. It's a 12-bit SAR ADC with a sampling rate of 200 ksps which is much higher than most consumer products use (44.1 kHz)....
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2
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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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1
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The relationship between bit depth and SNR in ADC
An 8-bit audio signal has a theoretical maximum SNR of 48.16 dB (20log(2^8)).
My question then would be, does this work in reverse, i.e. would an analogue audio (or video) signal with an SNR of <=...
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1
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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:
...
- 29k
4
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0
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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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3
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2
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329
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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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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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3
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2
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How to interface to a PDM audio source?
I hear about this technology, I read about it, I even see a bunch of MEMS microphones with PDM output. I can perfectly understand how it works (I have worked with DSP). However, I can't seem to ...
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How can I convert an audio PDM bitstream into analog form?
I have collected PDM bitstreams from MEMS microphones and I'm looking to convert them into analogue form. Does anyone know some practical implementation details on how to do this (beyond a quote from ...
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3
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S/PDIF: TTL to Coax Converter
I'm working on converting TTL S/PDIF to Coaxial level (0.5Vpp). I have implemented the following circuit using a Toshiba TC7W04, which is a 74HC04-type inverter:
But it does not appear to work in ...
- 515
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2
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310
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How to analysis this Operational-Amplifier circuit?
This is a reference buffer circuit that make a single-end audio input to be the differential inputs for ADC.
Circuit-1:
It does not like typical Op-Amp circuit of the same purpose like below.
...
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2
votes
1
answer
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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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2
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0
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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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2
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1
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590
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CSR8645 3.2 bluetooth module audio output merge negative pins
I want to use this module with my car aux in which is has 3.5mm 3 pole jack. This module has separate negative pins as LN and RN. I need to merge and connect these pins to aux in common negative pin.
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2
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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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1
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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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1
vote
1
answer
106
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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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1
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1
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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 ...
1
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3
answers
592
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Noisy AES audio signal in studio installation
This is a question about digital audio cables. I know this isn't an audio engineering forum but the question's specific to the physical connections and there's limited info online which I can find ...
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2
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I2S MCLK Generation
I'm working with a Sierra Wireless BC127 (Bluetooth Module) I2S master which is generating Left-Justified, 16 bps @ 44.1khz sample rate. The Bit clock is set to 2.822 Mhz.
I want to use a Cirrus ...
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1
answer
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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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1
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1
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271
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Is it relatively simple to design an ADC to ADAT interface with only a Toslink port?
For this project (I'm an experienced audio engineer but a relative beginner in electrical engineering) I really want to integrate a simple ADC to ADAT circuit in a patchbay I'm building so that I have ...
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1
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1
answer
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Overheating Linear Voltage Regulator In Lexicon Omega Audio Interface. Can I Swap With Reduced Amperage To Avoid Heat Probs?
I have a Lexicon Omega USB Audio Interface that's overheating.
Already tried several heatsinks, including the biggest one I could get (6"Hx2.5"Wx.5"D) with optimized cross-cut vertical fins, mica ...
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1
vote
2
answers
74
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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 ...
- 21
1
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0
answers
113
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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 ...
- 1,347
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0
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190
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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'...
- 1,347
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0
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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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0
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37
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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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1
answer
111
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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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1
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0
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123
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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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0
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72
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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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1
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0
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45
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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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0
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351
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How to interface a microphone to an I2S input to use HFP
For my group's SDP/Capstone we are doing a bluetooth headset of sorts. We are using a CYW20706 SoC from Cypress. Specifically, we are using a this CYBT-343026-01 Cypress module whch includes that ...
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1
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0
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876
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I2S DAC Volume Control
First of all, let me preface this with the fact that I'm not an EE -- I'm a hobbyist with some experience and a background in software development.
I'm trying to use a TI PCM5102A Audio DAC with a ...
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1
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1
answer
128
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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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0
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3
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1k
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Merging two different HDMI cables
I have two brands of broken HDMI cables that I need to join to make them longer.
Can't join them by color, because they are completely different. Plus, one of the cables has all the wires, the other ...
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0
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1
answer
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Low latency digital wireless audio transceivers
I would like to start a project developing diy low latency digital audio transmitters.
Issue is there is not much information online and I'm unsure where to start. I live in England UK, I would like ...
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0
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2
answers
171
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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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3
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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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0
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1
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What type of audio output does this symbol represent?
I have this picture. I want left, left ground, right and right ground output. Pin. But I can't understand it. Can somebody please help me. Thanks.
0
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1
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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 ...
0
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2
answers
188
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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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2
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69
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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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1
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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 ...
- 3,061
0
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1
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79
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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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1
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203
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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 ...
0
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1
answer
506
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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 ...
0
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2
answers
245
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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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How to play music on PAM8610 with ESP32?
I'm trying to use Xtronical's DAC audio library on an ESP32 to run 10W speakers. The board that Xtronical used is a PAM8403 which has a signal voltage range of -0.3V to +0.3V but as it can only run 3W ...
