We’re rewarding the question askers & reputations are being recalculated! Read more.

Questions tagged [audio]

Questions about designing electronics for measuring, processing, and amplifying audio signals.

Filter by
Sorted by
Tagged with
0
votes
1answer
39 views

Audio Amplifier Clipping

I designed a PCB with the following audio amplifier on it: https://eu.mouser.com/datasheet/2/302/TFA9896_SDS-1381317.pdf According to the data sheet, the amplifier is able to deliver 2.1W RMS into an ...
1
vote
1answer
28 views

Audio playback information when pressing buttons (school project)

My son is making a display (about A1 sized card) about space for school and I am trying to find out a simple way to add some buttons, that when pressed plays an audio recording with info about ...
0
votes
3answers
137 views

741 Op Amp Audio Amplifier with Noise

I have a project to build an intercom using op amp 741, because it is easy to find and is the only one that currently has access because of my location. Below the schematic diagram which I designed. ...
0
votes
0answers
15 views

MC34118 Voice Switched Speaker Phone Circuit Not Working

Video demodulation and modulation is performed in the project. At the same time by taking the same signal DC blocking with the capacitor, the audio signal is passed through the MC34118 integrated ...
0
votes
1answer
92 views

How to record a speaker?

Complete noob here. I don't need a ready to implement solution, pointers on what to read upon and ideas for even simpler projects to gain experience first are perfectly fine. I'm trying to feed both ...
1
vote
0answers
46 views

Can I make this Bluetooth speaker stop cutting off its speakers when audio signal goes silent?

I have a simple Bluetooth speaker that always seem to cut off its speaker circuit when the audio stream goes silent. This makes an audible popping noise, which is repeated when the stream starts ...
1
vote
1answer
78 views

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
votes
0answers
71 views

Audio amplifier instability inexplicable [closed]

here is the problem, I've designed a power amplifier of which I cannot post the schematic for security reasons, I hope you can help me the same by describing the problem. It is an analog amplifier in ...
0
votes
0answers
25 views

Difference in output between digital codec and analog filter

I'm working on a project which deals with filtering audio signals with a Low Pass Filter and amplifying the output. Currently, we are solving this using the TLV320AIC3111 audio codec by Texas ...
0
votes
1answer
37 views

What does changing the volume on a Bluetooth audio device really do?

For example, when playing audio from a smartphone through car speakers, you can change the volume on both the phone and the car. It makes sense that when changing the volume on the audio controls in ...
0
votes
1answer
45 views

Downsides to terminating a line level audio signal into an amplifier without an output resistor

I'm using a PCM5122 to output audio to a line level output as well as a PAM8406 amplifier. If I connect the PCM5122 to the PAM8406 AFTER the output load RC filter, then there is noise introduced ...
0
votes
0answers
20 views

Advice required re audio output stage for UM3561

I'm OK with digital electronics, fully capable of popping a 2n2222 and a suitable base resistor onto a GPIO pin but analogue is still quite a mystery to me, hence I'd appreciate some design advice ...
0
votes
3answers
99 views

8 ohms and 4 ohms speakers wired in series - volume issues

I have two identical sets of ceiling speakers connected to a cheap 2 channel Chinese micro amp - one 8 ohms and one 4 ohms, wired in series per channel. The 8 ohm speaker is too loud when the volume ...
0
votes
4answers
123 views

Is there a data transfer limit for virtual serial ports

I want to record 5/10 seconds of audio using an electret microphone and an STM32 nucleo development board and send it to my computer in real-time to be processed. I'm a beginner so I'm sure I'm making ...
0
votes
2answers
59 views

3.5mm Push to Talk Switch

I am looking to take a 3.5mm microphone line, insert a press button switch (a foot pedal in my use case) between the headset and the computer. I would like the switch to mute the mic connection when ...
0
votes
1answer
27 views

Audio codec output detection

I am looking for guidance on audio functionality test over USB audio codec. This audio output serves as Alarm to indicate certain events. The signal flow is ARM processor USB port --> USB Codec --> ...
0
votes
1answer
60 views

how to increase output power of multistage audio amplifer?

In the circuit given below, I'm working on an audio amplifer. It is driving a 4-Ohm load (speaker.) Input : 1.1V peak-peak sine wave of frequency 1Khz. Input dc = 12v Output : 4-Ohm load. Gain = (8 ...
0
votes
0answers
61 views

What do I need to make an Auto-Decibel Recorder?

I want to rig up a decibel-level sensor to an automated script that will record the times and decibel levels of door slams when I am not present, for later evaluation. I am a capable programmer and ...
0
votes
3answers
76 views

AC to DC rails sag excessively when loaded

I'm just experimenting with rectifying a 120v to 12v dual winding transformer and smoothing it out two a dual rail power supply while I work towards attempting to build a clean power supply. I ...
0
votes
1answer
88 views

Audio amplifier with strange open loop, is it an oscillator?

straight to the problem. Here is a picture of frequency response of my amplifier in the simulator (LTspice or Pspice both give same results). Normally, in the open loop i see a phase of 90° which ...
21
votes
6answers
5k views

Where do overtones in a 555 generated square wave come from?

I have built a 555 oscillator and connected it to a speaker. Using an oscilloscope I adjusted the 555 to generate a 2.5kHz square wave. I then held a microphone up to the speaker and fed the input ...
0
votes
1answer
76 views

Do passive RC filters need ground?

So, after a bit of searching I can't seem to find an answer to this anywhere, at least not in an easy to understand manner. Ok, lets set a scenario, if we have an audio input (in my project it would ...
0
votes
0answers
27 views

How do I convert this ADC code for STM32F3 to STM32F4 for colorchord?

I am currently trying to make the ADC driver code for the STM32F3 version of the colorchord https://github.com/cnlohr/colorchord code work on an STM32F4, as my F4 does not have an on board microphone. ...
0
votes
3answers
83 views

TDA2030L Audio distortion at high volume

I am using a TDA2030L audio amplifier to make my own subwoofer at home. The amplifier works well with the sound input (from a PC) at around 14 percent. The power input is 19V and 2A which is about 38W ...
0
votes
1answer
83 views

High vs Low audio transistor hFE (DC Current Gain). Which is better?

I'd like to preface by saying Rest in Peace my SoundBlasterX's back-panel transistors. What I tried to do, shown in the images below was ground the copper heatsinks I had glued onto the metal side of ...
0
votes
0answers
36 views

Sony Home Theatre Reciever producing high frequency constant volume noise while powered on

Equipment: Sony Digital Audio Control Center (Digital Cinema Sound) Model No: STR-KG700 Problem: High Pitch Buzzing coming from speaker output and headphone output (when plugged in). I have tried: ...
0
votes
2answers
38 views

Transistor amplifier keeps flickering between working and off

So long story short, i got some speakers from an old music player and they are huge (around 2.5 inches diameter and 1.5 inches high), i gave them new wires to use with a breadboard so i used a ...
0
votes
1answer
43 views

Microphone Pre Amp Book? [closed]

I'm wondering if there's a book that discusses resistors, capacitors, inductors, transistors, transformers, impedance, op amps, power supplies, and the general circuitry of a microphone pre amp. Thank ...
0
votes
0answers
16 views

Prevent click/pop from transient when bluetooth receiver disconnects?

I have a Logitech bluetooth receiver connected to my hifi to allow kids etc to play music from iPhones/ipads. However, it seems that the receiver itself has a sleep mode when no signal is being sent,...
0
votes
1answer
47 views

Why does this buffer apply a DC voltage through a high pass filter to the output?

simulate this circuit – Schematic created using CircuitLab What is the purpose of C3 and R5 in series between +9v and the Output? The only thing I could think of is that it supplies additional ...
0
votes
1answer
60 views

How to get stereo and mono signals simultaneously?

I have PAM8403 circuit module to drive my two 3W speakers. I want to drive a subwoofer with a different amplifier. I have a 3 inch subwoofer, and I'll get an amplifier for that. My question is how do ...
0
votes
1answer
58 views

Split Audio lineout into two different amps

I am using a 3116d with a lpf and a 7498 for the mid range. The audio signal comes from a common source. The cables are split and soldered, so that both amps receive the same input. However, doing so ...
0
votes
1answer
33 views

How to create a plug detect of a 3.5mm audio jack with 2 connection that carry an AC signal

Hello i am creating a circuit that take in a 3.5mm audio jack from a Non-invasive Split Core Current Transformer AC current sensor and according to its datasheet the: ...
0
votes
1answer
56 views

How can I easily inject a tone from a DAC into an XLR audio signal?

Let's say I have a mic-level signal running on an XLR cable - a vocal microphone going to a mixer or preamp. I'm looking for the simplest way to add another mono audio signal to the line. I've got a ...
4
votes
2answers
88 views

The Pin 1 Problem in Audio, Star and Mesh Ground, and Contradictory Grouding Practices in Audio and Digital Systems

I recently came across the concept of "Pin 1 Problem" known in the pro-audio electronics. It seems straightforward at first, but becomes confusing when it comes to grounding. Let me describe the ...
0
votes
0answers
60 views

Audio amplifier output bypass capacitor

I'm currently designing a single rail power supply audio amplifier and just wondering what the benifits are (if any) and if its worth including a film/poly capacitor in parallel with the large ...
0
votes
0answers
62 views

Make MIDI messages and audio signal transit in the same jack cable

I know it's a crazy (bad) idea, but still: I hate having many cables attached to a music instrument when I move in the room. Let's take the example of a Akai MPC500 sampler: it is battery powered (so ...
0
votes
1answer
43 views

pam8403 using low wattage speaker

I am using the output of usb sound card as an input to PAM8403 ic with specs from datasheet. However i am using 4 ohm 0.5 W speaker. So i have tried testing with that and it works but sometimes with ...
0
votes
1answer
23 views

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.
2
votes
1answer
87 views

Analog Switch times for popless audio

If I am using a CMOS switch, how much do I have to slow down the switch time so that I don't experience a pop in my audio signal out of my amplifier and how would I accomplish that? The switch time ...
1
vote
0answers
46 views

Should I connect metal enclosure to -V or to virtual ground?

I've built a headphone amplifier powered by a switch-mode 2-pin wall wart power supply. Internally a virtual ground is created by dividing and buffering the supply voltage. Input and output signals ...
0
votes
2answers
90 views

Invert or turn Aux Signal mono using Rotary Switch

Is it possible to use a 3 Pole 4 Position rotary Switch to do the following on the respective positions: Send the Aux signal through normally Invert Left and Right Send the Left Signal to both ...
1
vote
3answers
92 views

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 ...
-1
votes
2answers
61 views

What happens if I connect computer to phone with aux connectors and just put music on each? [closed]

If I connect an aux cable, like that one: https://5.imimg.com/data5/OG/IB/MY-9820141/aux-cord-for-audio-500x500.jpg Between my computer and phone, and start playing music on both of them, what will ...
3
votes
2answers
61 views

How to calculate “effective source impedance” in this audio mixing circuit?

I am new to electronics and have recently been trying to get my head around audio mixing. I stumbled across a helpful introduction by Rod Elliot on passive and active mixers, but I am stuck on a small ...
0
votes
0answers
47 views

JAMMA Arcade: How to properly wire audio

I’m trying to wire build a Jamma arcade cabinet from scratch. I have a question on how to properly wire audio. The Jamma standard have two pins related to audio (+/-). I have connected + to a phono ...
0
votes
1answer
34 views

Is this circuit for Piezo Transducer and corresponding resistor values correct?

I want to drive this piezo transducer (https://www.mouser.com/datasheet/2/670/cpt-9019s-smt-1310960.pdf) at 3V and 4kHz with STM32F0 microcontroller. This is a follow-up to my previous question (Is ...
0
votes
1answer
35 views

Audio jack adaptor [closed]

Can I connect two headphone to each other using a female to female connector and setup communication between the headphones?
0
votes
1answer
40 views

Is this circuit for Piezo Transducer sufficient? [duplicate]

I want to drive this Piezo Transducer (https://www.mouser.com/datasheet/2/670/cpt-9019s-smt-1310960.pdf) directly from a pin on my STM32F0 microcontroller. I don't want to use a BJT transistor because ...
1
vote
0answers
72 views

Struggling to get an amplified sine wave over a small inductor at low frequencies

I am building a power amplifier circuit to amplify a sine wave over an inductor from a function generator. However because the inductor is small and i'm running at a low frequency I am getting ...