Questions tagged [audio]

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

Filter by
Sorted by
Tagged with
0
votes
3answers
150 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. ...
14
votes
6answers
56k views

Over what frequency range can the microphone of smartphone receive the sound?

I have a project in which I am considering using the microphone from a smartphone for the reception of inaudible signals (> 15khz). What is the frequency range that such a microphone of receive sound?...
1
vote
1answer
160 views

Driving Lights with Audio Amplifier

I'm working on a project where I want to have christmas lights (or LED strips if needed) react to music. In this case, the end goal is to have them pulse to the beats/bass of the music. There's a lot ...
1
vote
1answer
126 views

Splitting Audio Out - are there any issues I am not seeing?

first post, so I hope this isn't TOO stupid a question. I am planning on building this circuit: https://github.com/trash80/Ym2149Synth/blob/master/Ym2149SynthSchematic-V29082016.pdf which eventually ...
0
votes
1answer
194 views

Studio Mic --> 3.5mm jack not working

I have created a system to plug my studio mic (MXL 990) into my MacBook's 3.5mm headphone jack that consists of the following system: Mic -> AC Power supply for the mic -> 3-Prong microphone cable to ...
0
votes
1answer
98 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
1answer
152 views

Buffer, amplify, filter, sample - In which order?

I'm trying get an audio signal from a high impedance source (guitar or mic) to an ADC. Some casual research suggested that I should filter my signal before amplifying it. My current mental design is:...
1
vote
2answers
86 views

Configuring Frequency Bandwidth and Input Signal for Bandpass filter circuit

How do I set and configure the frequency bandwidth I want the filter to output to a device? I am using a physical passive bandpass filter which I intend to take the signal in and filter it and output ...
3
votes
1answer
224 views

Amplify Raspberry Pi Zero W Audio with 60s Tube amplifier circuit

First of all, thank you for taking a look at my question. Electronics is not my field of expertise, and I have found myself a bit stuck. I have been restoring some old 50s and 60s tube amplified ...
1
vote
1answer
309 views

Opamp Design for Low Impedance Sources?

I am terribly confused ... I tried myself at building a low impedance guitar pickup some time ago. Quick LowZ Pickup Intro Basically just two loops of aluminium with two magnets, a humbucking guitar ...
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
82 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.
2
votes
1answer
158 views

Can I connect a MEMS mic directly to this spectrum analizer chip?

I have a ICS-40181 MEMS mic and want to do basic spectral analysis using the popular MSGEQ7 chip for the purpose of a sound reactive project. Can I simply connect one into the other (with cap/res as ...
1
vote
0answers
28 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
4answers
127 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
1answer
40 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 ...
2
votes
1answer
203 views

Why would this Class D Audio Amplifier have low current draw?

Disclaimer: Saying I have very little knowledge of electrical engineering theory is an overstatement. I very much appreciate your help and patience. I'm not finding any questions similar to mine, but ...
1
vote
2answers
357 views

How can i replace a electret mic input with headphone output as input

I'm using a SIM800L GSM module for my project. In this module there is a electret mic input pin but I want to give audio to this module from headphone output from a mobile (There is no line in pin ...
0
votes
1answer
47 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
21 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
106 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
2answers
62 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
183 views

Op-amp control theory

back at it again trying to use your genius brains. I have been trying to teach myself audio amplifier design. The big road block I am getting into is the control theory part of it, meaning how does ...
1
vote
1answer
28 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
0answers
67 views

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

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
1answer
63 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 ...
1
vote
1answer
129 views

Repair lifted ground pad on power amp

I'm repairing a 250W bass power amp board and one of the problems is that the pads for two ground wires have lifted off the board. It looks like it has had something of a bodge repair done before and ...
1
vote
1answer
172 views

THAT4315 audio analyzer - capacitors getting hot

I have designed a audio spectrum analyzer circuit with THAT4315 and a drivers for IN-13 bar graph nixie tube to visualize the signal level. To supply +-12V to the opamps, the Meanwell NSD15 module is ...
0
votes
3answers
77 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 ...
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
2answers
166 views

Audio ADC voltage level SNR question

I keep looking for Audio specific ADCs and the majority of these devices work at low voltages on the analog circuitry (5V for example). Lets say we want to process an higher voltage audio 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
28 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. ...
2
votes
1answer
170 views

fixing the amplifier in an old arcade machine

I just joined and need help. I'm trying to fix the amplifier in my Chicago coin speedway arcade machine. It basically works but it has a bad hum in it. I did replace a couple capacitors that were ...
0
votes
1answer
214 views

Start/ stop 5v motor from headphones jack

I would like to make the jaw of a plastic skull open/close based on words spoken by a Raspberry Pi. I can make the Pi send the audio to the headphone jack, and would like to use this output to run 5v ...
0
votes
1answer
161 views

Would it be ok if I try to measure an audio signal using a 15m BNC Cable?

I would need to use a 15 meters BNC Cable (RG58) in order to measure an audio signal that goes directly to a pair of earbuds. This means, the test point would be exactly before the balanced armature ...
0
votes
1answer
108 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
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
261 views

MICBias Ground in audio codec

MICBias is the voltage required for microphone to power and record signal at full levels. What will happen if we ground MICBias, is it means we are disabling microphone.
0
votes
0answers
37 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: ...
1
vote
1answer
340 views

Common audio signal voltage range on Line out connector

What is typical audio signal voltage range on Line out connector of consumer electronic devices? (Vmin/Vmax) I need specify Input voltage range to calculate op-amp. ...
0
votes
2answers
39 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
2answers
275 views

using the mcp42010 for audio attenuation

I would really appreciate some help here, I've spent a lot of time on this and can't get it right. looking at datasheets and answers here actually made me even more confused... I'm trying to control ...
0
votes
1answer
44 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
17 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,...
6
votes
3answers
57k views

How to determine appropriate speaker cable gauge?

When wiring speakers to a 100W consumer-grade amplifier, how do I select an appropriate gauge cable (for 8-ohm speakers)? Also, if 14 gauge cable is sufficient, what harm is there in using a heavier ...
1
vote
1answer
398 views

Using an audio splitter when using Arduino to read from an aux cable

I am currently able to feed a 3.5 mm aux cable into my Arduino and read its values, but I'm not able to hear the sounds being played. I wanted to solve this problem by using an audio splitter and ...
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
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
63 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 ...