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

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1answer
28 views

Using Nexys 4 audio port [on hold]

I have a digilent Nexys 4 board that I am using for learning Verilog. I have written a code that requires connecting an audio speaker to the board for evaluating. What is the speaker that can be used ...
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1answer
59 views

VCA Using JFET and Op Amp

Just messing around with LTSpice I came up with this VCA that simulates shockingly good for what it is: I don't recall ever seeing the use of an op amp to mix the signal and control voltage in an ...
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0answers
52 views

Can a PC sound card (realtek) be used to transmit radio signals

If I were to use software such as PureData to generate a 20 KHz sine wave and perform AM on the wave, played it out the line-out on the right channel, with the ground and the left channel sent to a ...
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0answers
43 views

Noise on audio circuit when powered by USB

I built a simple microphone boost circuit which works well with a 3V coin cell however when I switch to USB to power it (battery removed, of course), there's a bit of noise in the 200Hz to 10KHz ...
0
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1answer
44 views

What frequency range is acceptable for a speaker in an audio amplifier

I am building an audio amplifier using a lm386 amplifier with a 12 volt supply driven from a headphone jack. I am looking for a speaker that will work well in this setup. Currently I am using a ...
2
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2answers
105 views

Low voltage audio amplifier clips on 8 ohm loads

Exposition time: One could call me a freshman in electronics and I just designed my first little audio amplifier for headphones. (Pocket design, I want to be able to drive 4 headphone pairs from a ...
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2answers
39 views

Sampling frequency from audio jack

I want to start a project where i'll sample directly from the audio jack. Now i don't know what the sampling frequency should be. I don't know what is the maximum frequency of sound, i don't know it ...
0
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1answer
30 views

Size of passives for active filter

I am working with the CS42436 codec, and in their datasheet, they have recommended values for components to be used in an active filter that takes the differential outputs from the DACs and converts ...
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2answers
2k views

What data format do audio cassettes use?

How do the sound pressure values correspond to the magnetic domains on the tape? Is the format analog or digital?
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1answer
24 views

Make outputs single ended on CS4234

I am working with the CS4234 codec for a project It has 4 ADCs and 5DACs. One thing that is confusing me is that the pins are labled AOUT1- and AOUT1+ in the similar fashion for all ADCs and DACs. ...
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1answer
45 views

Headphone has no sound if fully inserted in jack [closed]

When I connect my headphone to headphone jack in my laptop, I don't hear any sound. Unless I do not fully plug it in and instead just plug it in around 50%. Sometimes I hear sound but it is all ...
0
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1answer
31 views

Impediance mismatch and amplifier question

I am converting an aviation headset to take a Bluetooth signal. The headset speakers are \$150\Omega\$, and the Bluetooth adapter I think is \$10\Omega\$. The mic will not be used. Can anybody ...
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2answers
53 views

Bias headphone audio signal for use with digital potentiometer?

I am attempting to control speaker volume via a digital potentiometer, the problem being that audio signal goes both above and below 0V, for regular potentiometers this is no problem but for digital ...
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2answers
165 views

How to improve lm386 amplifier circuit

I am new to the world of audio amplifiers however i am quickly trying to learn. I have built a simple circuit using a circuit based on what I read in the database. The circuit works however there is ...
1
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0answers
33 views

SPDIF digital audio to I2S to USB controller

I'm looking to take a digital S/PDIF audio signal, decode it as necessary, and send it to a USB controller chip configured as a USB Audio Class device so I have plug-and-play with standard OS-provided ...
0
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0answers
8 views

Stream audio from smartphone to arduino [migrated]

Is it possible to stream audio from smartphone to my arduino? And if yes, what does it require? Does it require programming from the smartphone side? I know programming on the arduino. I have even ...
0
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0answers
35 views

Is there a free HE-AAC decoder suitable for ARM MCUs?

Question itself: Is there a free (of charge, but if it's also open source that's even better) audio decoder for HE-AAC (AAC with SBR) that can use the FPU and/or DSP instructions in an STM32F4 ...
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0answers
38 views

Switching Power Supply makes speakers hiss

I have a computer with a 5.1 soundcard, that I'm using to run a standard PC 2.1 setup (Corsair SP2500) on the main audio output, and two rear surround speakers I had laying around. The speakers in ...
1
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1answer
64 views

Compromise needed combining virtual grounds

This is a long story for which I hope my proposed solution to a problem I've created will be a stable one. But op amps can surprise you, so let me explain. The circuit is large and complex, so I'd ...
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2answers
87 views

Mic Amp Mixer and Audio Distribution, Won't Work! Help! (Update 2) (Solved!)

I'm new to this forum and I really don't know much about Audio Amplifier Circuits. Hope you can help me. Here it goes: So basically what I'm trying to do is a circuit that mix 3 channels, ...
2
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3answers
109 views

Mixed analog-digital power supply

I'd like to build a project where I'm essentially controlling analog signal generation in the audio range from a microcontroller. In other words, an analog synth with digital control. I'm at the stage ...
0
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1answer
63 views

Use of Audio Tranformers in Amplification

I came across this ckt to make a wireless ear phones using Infrared Signals from IR LEDs. I am unable to understand the use of Audio Transformer here to amplify the audio signal, instead OpAmps would ...
0
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1answer
39 views

Architecture of speaker (drivers) to get an acceptable level with small dimensions

I'm trying for a couple of days now how to get a good volume out of a small speaker. My reference is e.g. an iPhone internal speaker which has a good loudness (up do 100dB) in the higher and middle ...
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1answer
84 views

Circuits in audio amplifiers to protect speakers

I hear that there are at least two kinds of circuits in modern audio amplifiers solely for the purpose of protecting the speakers against excessive loads on powering on and off. Particular function ...
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1answer
63 views

From grounding to audio amplifiers

Ultimately I would like to assemble this simple audio amplifier: Given my lack of any significant knowledge in the topic I have several problems and questions. Grounding: In the thread What is ...
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2answers
70 views

newbie question: can I plug a 250v power strip into a 120v power outlet (and then connect three 120v power adapters to the power strip)?

I'm sorry if the question is too dumb, but I was wondering if I could connect a power strip rated for 250v into my home's power outlet (120v). I wanted to connect 3 power adapters rated at 120v to it ...
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2answers
62 views

Can you turn a non-USB audio mixer into a USB mixer?

Ok. Pretty sure this sort of thing isn't possible but hey ho, I have a Behringer Eurorack UB1202 multi-channel mixer. I'm just curious if there is any way way to turn it into a USB ...
0
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1answer
33 views

How do I find the corresponding level of those audio samples?

I am trying to self-study this problem for a future exam. The writings in red are solutions to the question. I have a problem in number part e of the question where they find the corresponding level ...
0
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1answer
45 views

Attenuation in speaker crossover design

In the loudspeaker crossover circuit below, I believe the purpose of the resistor is to attenuate the signal to the second speaker (the tweeter). However, in circuits I've seen that are supposed to ...
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0answers
70 views

Noise-cancelling headphone concept

Inexpensive noise-cancelling headphones use a single microphone located in a little lump between the plug and the earphones. They seem to work fairly well for ambient noises, but not for handling ...
0
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1answer
51 views

Replace potentiometer with digital version (Speakers)

I am trying to get my PC speakers to be controlled by my arduino. I've taken apart the control and it seems very straight forward, just need a few questions about subbing the manual pots for digital ...
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1answer
69 views

How to use whole rotation of log potentiometer?

I want to use a Log Potentiometer to adjust the loudness of a speaker. Therefore I connected the Stereo logarithmic pot with 10 kOhm resistance to a Sonos CONNECT:AMP with an output of max. 110W (8 ...
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2answers
109 views

How to separate two DC voltages in s dual power supply?

I have a dual power supply (Lacie ACLG-51) that supplies both 12V DC and 5V DC with a common neutral (3 wires) I have used it to drive a little system composed of a Raspberry Pi (5V), USB HUB (5V), ...
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1answer
53 views

i2c Error in using BeagleBone Black with custom audio cape ( using ti's TLV320AIC3107 codec )

I have made custom audio cape using TLV320AIC3107 codec and here is a schematic diagram. For connection with BeagleBone Black I refer audio cape which is available in market. here is a link: ...
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3answers
65 views

How to stretch high frequency digital signals (e.g., MIDI) into the audio range

I'm curious about the possibility of sonifying MIDI data, which has a bitrate of 31250. The range of human hearing extends to about 20kHz, which means that the fastest bits of the signal would lie ...
1
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1answer
56 views

Send digital data over same wire as analog data

I am trying to modify an existing circuit that I am able to send another digital signal over the same connection. My circuit is a so called "Partyline Intercom" which is based upon the schematics of ...
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2answers
53 views

In which way can I use operational amplifiers to amplify XLR signals?

I'm asking myself, how I can use operational amplifiers to amplify XLR signals? Let's say my XLR input gives me GND (1) Signal+ (2) and Signal- (3). Can I simply connect 3 and 2 to my operational ...
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2answers
89 views

Why are these two potentiometers affecting one another?

Let me first say, that I am no electrical engineer so thanks for taking the time to deal with a layman. Background In my workshop, I have two sets of speakers hooked up to a common 3.5mm audio ...
0
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1answer
83 views

How to figure out battery life of audio amplifier?

I have a design of an audio amplifier. It has some special features but basically it takes in an audio signal does some filtering, and amplifies it through a class D amplifier chip. The chip says it ...
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2answers
83 views

How to choose a transistor for amplification

I've been trying to find information on choosing an NPN transistor but everything I've found seems to apply to saturated transistors only. I'm basically trying to amplify the current given from a 3mm ...
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0answers
71 views

Cost effective high quality audio recording & playback design

For a few days now, I'm looking for a cost effective way for recording a few minutes of audio in high quality 44.1KHz @ 24bit and be able to save a bunch of these "tracks". I thought to use SRAM + ...
2
votes
2answers
69 views

Input voltage for LM4862 audio amplifier

I just started working on an embedded side project that requires me to pump .wav files through headphones. My main microcontroller is a PIC32, and my audio amplifier is an LM4862. For the DAC ...
0
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0answers
21 views

How could I connect the TI C2000 to a TI PurePath CC8531?

My goal is to have a microphone connected to the TI C2000 for analysis of the signal and be able to transmit the digital signal between the C2000 and the TI PurePath. Alternatively, I could connect ...
5
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6answers
1k views

What is the physical/electrical limit of audio quality?

A few days ago I was in a class about electronics on my study. The first lesson was an introduction into the main subject, bits, analog signals, conversion, etc. An example was asked by the teacher: ...
2
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1answer
69 views

How can I find and remove servo/motor noise from this audio amplifier?

I am troubleshooting an audio noise problem in project which has several components wired together as follows: Overview: The overall project does some motion control with a servo and has an audio ...
1
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1answer
47 views

Class D inductor current calculation

How do I calculate the required inductor current (RMS, saturation) for a class D amplifier? Assuming the following configuration: Speaker impedance (Z) = 4 ohms Power output (P) = 400W ...
2
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1answer
78 views

Electret Mic Circuit Using JFET Bootstrap

I thought this circuit was clever so I'm sharing: The JFET current source is bootstrapping the electret and thereby providing 20dB of linearized gain. The bootstapping network also provides for ...
0
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2answers
110 views

What is this connector?

I'm working on soldering a 3.5 mm female jack to the Thinkgeek Personal Soundtrack Shirt Controller so I can output to any speaker I please, however I am wondering if this is an actual connector I can ...
1
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1answer
55 views

Routing Audio Ground - needed or not?

I'm trying to build a guitar pedal switcher (efectively a box that provides multiple effect loops that can be independently bypassed from a single microprocessor) and while building a working ...
3
votes
2answers
84 views

Quiet inductors?

Are certain types of inductors more likely to create an audible sound than others when under use? Is there any sort of best-practice or guideline to minimize such humming or buzzing sounds? I.E. ...