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

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-3
votes
1answer
68 views

What is I2S and DSP? [on hold]

I am learning to build an amp.(TA2020, circuit from datasheet). I would like to know about the I2S and DSP, and when and how to integrate these tech. Specifically speaking, if i am suppose to ...
-2
votes
0answers
32 views

Adding different input modules to amplifier [on hold]

I learning to build a TA2020 based amplifier (built from datasheet). The input pin, according to datasheet, accepts analog sources. I would like to know if by simply adding bluetooth and usb modules ...
-1
votes
0answers
66 views

Help building an amplifier [on hold]

I'd like to design a Class D Amplifier for household listening. The specifications from the point of view of a consumer are: it should be portable it should provide at least 8h of playback time ...
0
votes
1answer
30 views

Digital audio clock recovery from UDP

My question is how can i recover the clock timing of digital audio transmitted over ethernet using UDP? I am streaming live audio over Ethernet using UDP. My set up uses two STM32F407 discovery ...
3
votes
1answer
108 views

Interfacing an RCA audio output to a microcontroller ADC

I'd like to connect the audio output from a set-top box (and similar) to a microcontroller's ADC. They all have an RCA connector so I was wondering what sort of circuit may be required to interface ...
0
votes
0answers
22 views

Czech RF10 Battery Help [closed]

Need some help. I purchased a Czech RF-10 radio which has a battery box with Five Ni-MH "D" cells inside.. (see prc68.com) I would like to know how to recharge these batteries. Can I use a universal ...
0
votes
1answer
38 views

Power a laser from Arduino using a audio cable/ jack plug?

I want to power a laser from an Arduino, and have a connection between a phototransistor. A easy connection seems to me a audio cable with a jack plug. Is this possible? Power consumption of the ...
-1
votes
1answer
114 views

Simple, Cheap, and Poor Quality Audio Amp [closed]

So I am attempting to build/design a audio amp. Basically around a 1 watt amp for a walkie-talkie. I'm planning to run it off a 9V battery. When thinking about a power amp several ideas came to mind. ...
-1
votes
1answer
61 views

Am I doing this right? (LED's to music)

simulate this circuit – Schematic created using CircuitLab I have been charged with designing and making a circuit that makes LEDs brighten or dim to an audio source. At the time I ...
-4
votes
1answer
49 views

how can i make my own sound emiting personal alarm? [closed]

I'm a jewelry designer who wants to create an attack alarm that looks like jewelry. I'm having trouble finding info online about how one works. Is there anyone here who can help me or teach me how to ...
0
votes
3answers
92 views

Lossless FFT on audio data

I have an application where I'll be receiving an audio stream, much like using headphones, into my processor. I would like to run FFT and various DSP algorithms on the sampled audio and then spit the ...
1
vote
1answer
63 views

1/8" i/o components

Im looking to make a microcontroller that has one stereo 1/8inch input and one stereo 1/8inch output and a processor that can effect / filter the audio. Im looking around for microcontroller tutorials ...
1
vote
0answers
27 views

Connect electret mics to computer [closed]

I'm trying to do cross correlation on the signals arriving at a microphone pair. I do not want to record anything. Before doing this on a development board (like the beaglebone/board), I decided to ...
0
votes
0answers
31 views

Recommended setup for recording and processing 3 or more audio signals

I don't want to ask for specific products but the terminology in general: for a future experimental project I want to record multiple audio signals and I don't know yet which frequencies I'm ...
0
votes
1answer
98 views

How do I solder a LED in place of an earphone?

I have a super basic bluetooth headset. I've taken off the earphone, and want to put a very low power, basic LED in its place. I plan on just soldering the anode to the red wire and the cathode to ...
0
votes
1answer
49 views

Audio Playback: Missing vowels

I am new to audio processing, I have a dsPic33F and I wrote a simple audio playback (when you speak on the mic it is played immediately on the speaker). However some vowels don't produce any sound. ...
0
votes
0answers
20 views

Problems sending mic input to IC preamp

I am using the following product: http://datasheets.maximintegrated.com/en/ds/MAX98089EVKIT_TQFN.pdf It is an audio codec eval board with RCA input jacks. They provide software for setting all ...
0
votes
1answer
68 views

HDMI microcontroller / DSP tutorial

I know a little bit about microcontrollers. I want to first say this question will be over my head but I'd like to do the project anyway... I want to have a HDMI input, add effects to the sound, then ...
0
votes
1answer
60 views

Is a subwoofers RMS/peak wattage rating subject to the enclosure type?

The RMS and peak wattage rating of a subwoofer (or any speaker) show afaik how much power it can safely handle without damaging it. But is this true for both sealed and ported enclosures? (assuming ...
1
vote
2answers
62 views

Play PCM stored in EEPROM without microcontroller

Is it possible to connect digital-to-audio converter with a EEPROM storing PCM data to play that data with a speaker? I am interested in a solution that does not employ any kind of microcontroller. ...
0
votes
0answers
32 views

Codec to Audio Processing Chip to SD Card

I posted a previous question about a project I am working on that will take a microphone output, send it through this codec and output the now digital signal via the SPI, process it using this audio ...
0
votes
2answers
108 views

What exactly does Watts and dB signify? [closed]

Now this is confusing. At some point i read that higher watts does not neccesarily signify high volume sound. An amp rated at 100w and other rated at 50w dows not mean the former is 2 times louder. ...
0
votes
1answer
55 views

Headphone jack PCB connection

Im connecting a PCB mounted headphone jack to a circuit Im designing that takes a gnd, V+ and V- input from the 3 way 3.5mm headphone jack. However when I read its data sheet it has three connections ...
3
votes
0answers
48 views

Modifying headset's microphone to hear from it? [closed]

Problem? I have a headset with a microphone, like this: Good for you. What do you want? I want to use my headset's microphone as a real microphone. It's already a real microphone, you noob. ...
1
vote
1answer
56 views

SMPS --> TDA8920 | +V GND -V op-amp

I'm thinking about buying a TDA8920 audio amplifier and power supply and I need some help buying the right PSU. See edit below. So here's what I know. L (AC) = Live (Brown*) N (AC) = Neutral (Blue*) ...
3
votes
2answers
107 views

Reducing a line signal in the home HiFi system

In my HiFi system the CD player is playing way too loud compared to the other sources (radio, streaming gadgets, tv. etc) I figure a simple voltage divider say 33kohm and 27kohm would reduce with ...
0
votes
1answer
32 views

Kaustic Machine's Atari Punk Console: Line Output or Log Pot?

I'm planning to make a atari punk console for an electronics project, but i have a question, the original circuit published here: http://compiler.kaustic.net/machines/apc.html has a "line outout". Is ...
0
votes
1answer
55 views

How to filter low frequency noise on power supply from ChipCorder?

I've built a circuit using an ISD4003 ChipCorder, which is an IC for recording and playback of audio (in a telephone answering machine, for example). I've written code to send the SPI commands to ...
0
votes
1answer
39 views

Poor man's equalizer with a few digital bandpass filters - how to overlap band edges

I am trying to implement an equalizer in an FPGA. It's not hifi or anything so 3 or 4 bands should cut it. So I have a low, band, and high pass filter covering the entire voice spectrum (0-4kHz in ...
0
votes
0answers
30 views

PCM codes. Which to choose

If a sampled voltage sits on the line between two steps of a pcm code which one do you chose? ie 0.75v with pcm give an equivalent value of 96 which lies on the line between 92 to 96 and 96 to 100. Is ...
1
vote
1answer
47 views

Line out bias on sound card output

I recently bought an USB sound card to do some measurements/experiments with. What I want to do first is to build a simple amplifier for the headphone output. Therefore I took the sound card apart ...
1
vote
2answers
59 views

Understanding audio port schematic

This is a typical audio socket. In the datasheet there is a schematic, but it only has description for 3 pins out of 5, what is the use of the rest of the 2 pins?. Also what does the symbol in front ...
-2
votes
1answer
61 views

Finding a chip that can record and playback 30 seconds of audio [closed]

I would like to make my own circuit to record a tune and then playback about 30 seconds of audio. I don't want it to be very complicated. I have basic soldering skills but an IC in an easy to ...
2
votes
3answers
72 views

Audio PWM DAC filtering

I have an msp430 synth project and can't decide on the output: I get an 8 bit ~45kHz PWM output out of the chip which I'd like to use as an audio signal, but I am unsure whether I can just stick ...
5
votes
2answers
420 views

Naively mixing two (or perhaps more) audio signals

this is my first question and I am very much a beginner in electronics so I apologize if this is a too stupid question. I have Atari punk console and another small homemade audiomaking circuit. These ...
0
votes
1answer
136 views

VU meter from line input or speaker input?

Is any of the the two following schematics for Line input? Or is it for the amplified signal that goes to the speakers? ( source ) ( source )
0
votes
1answer
30 views

How to prevent data throttling with audio codec streaming

I am sampling a incoming audio stream at 8Ksps. I have a codec that takes ~1.6ms to encode a packet of data (80 samples) into an encoded packet (5 samples). At this rate I get 8000*1.662e-3 ~= 13 ...
1
vote
1answer
66 views

MCLK in I2S audio protocol

I am working with the I2S audio protocol in one of my projects and I'd like to use it in one of my final projects for a class of mine. Quite honestly though, I don't entirely understand the MCLK ...
2
votes
0answers
93 views

Eliminate/reduce speaker pop when powering off amp [closed]

I'm repairing an old 1970's record player and one of the items on my list is to try and reduce the loud 'pop' noise when switching off the amp. I've done a little research and it seems there are a few ...
1
vote
4answers
156 views

Why use 2 isolated grounds in Mackie 220W Power Supply?

I recently took apart a Mackie 220W power supply for an analog sound board. Much to my surprise I found the following scheme: Earth grounded: 48V -18V 18V Seperate, isolated ground: 12V 5V I am not ...
2
votes
2answers
61 views

Door phone audio signal to pc soundcard

I need to interface door phone system to a pc soundcard to listen and talk to the external unit. The door phone to interface is an as yc/200 of BPT and its a classic analog 4+n wires Door phone ...
2
votes
1answer
76 views

Audio from Arduino Due's analog outputs to line-in

Line inputs are high-impedance, Wikipedia says around 10kΩ. Due's DACs provide 0-3.3v (actually less) and are rated at 3mA max. \$\frac{3.3\rm{v}}{10\rm{k\Omega}}=0.33\rm{mA}\$. According to ...
4
votes
2answers
181 views

Audio from Arduino Due's analog outputs using LM386

Due's DACs provide 0-3.3v (actually less) and are rated at 3mA max. As far as I know, common speaker/headphone impedances range from 8Ω to a few hundreds, so driving these from the DACs will destroy ...
0
votes
1answer
36 views

Measure/Access Information from small device through audio jack (mic)? [closed]

I've got a small device that I have not yet opened. It sends some unknown sequence of voltage and current through a medium for a few seconds thereby calulating and then displaying a result value on a ...
-3
votes
2answers
77 views

Effects of a subwoofer on computer components [closed]

Ok so here's a question that I've only seen asked once, what are (if any) the adverse effects of having a subwoofer included in a PC case mod? The Backstory: I've got an OK case. Looks nice, has cool ...
1
vote
1answer
112 views

Gain of this schematic

I am interested in the following compressor, which I reverse-engineered from a pcb (there might be some mistakes, but I don't think so) (open the schematic in a separate window to see the small ...
1
vote
2answers
67 views

Is it possible to use half of a LM13600 instead of a CA3080?

I'm in need of a replacement for the CA3080 for my VCO that I would like to build. I have come across the LM13600 and was wondering if anyone knew if I could just use half of it and operate it without ...
0
votes
1answer
139 views

Short circuit or disconnect to bypass a compressor

I have an Altec Lansing ATP3 2.1 audio system PCB which I reverse-engineered, and I would like to bypass the JFET compressor that's on it. Its active components are a JFET and four op-amps. I will ...
7
votes
1answer
210 views

Help me modernize this audio circuit

When I was a kid, I built this circuit. You hook up a small capacitor to the test leads or maybe a couple in parallel and the speaker will output a different pitch based on the test capacitance. I ...
1
vote
1answer
84 views

Crossover design

I have just built a really simple amplifier based on an LM386: And I am now looking to design a crossover to go with it. What is the most appropriate type of crossover design to use here? I am ...