How to connect audio output to an ADC

  • Thread starter Thread starter michael1978
  • Start date Start date
  • Tags Tags
    Adc Audio Output
Click For Summary

Discussion Overview

The discussion revolves around connecting audio output from a radio tuner to an analog-to-digital converter (ADC) for processing with Arduino. Participants explore the specifications of audio output, the functionality of ADCs and DACs, and the feasibility of sampling audio signals with Arduino hardware.

Discussion Character

  • Technical explanation
  • Exploratory
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant initially confuses DAC with ADC, prompting clarification on the correct terminology.
  • Specifications for the radio tuner’s audio output are discussed, including signal levels and load impedance.
  • Some participants suggest searching for articles on analog-to-digital conversion and Arduino processing.
  • Questions arise regarding the operation of R2R DACs, particularly whether they function with switches or automatically.
  • Concerns are raised about whether the Arduino's ADC can sample audio signals quickly enough for quality audio processing.
  • Details are provided about the Arduino's ADC operation, including clock cycles needed for accuracy and potential sampling frequencies.
  • Participants note that amplification may be necessary to utilize the full range of the Arduino's ADC.

Areas of Agreement / Disagreement

Participants express varying levels of understanding regarding the connection of audio outputs to ADCs and the capabilities of Arduino in processing audio signals. There is no consensus on the best approach or the effectiveness of the Arduino's ADC for audio applications.

Contextual Notes

Participants mention the need for amplification to achieve the desired output range from audio signals and discuss the limitations of the Arduino's sampling frequency for quality audio.

michael1978
Messages
434
Reaction score
19
hello to everybody,
can somebody help me,
how to connect audio output to dac
i have a rado tuner,
i just need to connect audio output to adc after to connect to arduino
thnx
 
Last edited:
Engineering news on Phys.org
michael1978 said:
how to connect audio output to dac
No. A DAC converts digital to analog ... you probably mean an ADC (analog to digital converter).

1. What are the tuner audio output signal level specifications?
For example, standard "Line Out" is 1 milliwatt into a 600Ω load (about 0.77 volts RMS; 2.2 volt peak-to-peak).

2. What is the ADC manufacturer and part number?
 
yes you right i just wake up,
is 1 milliwatt into a 600Ω load (about 0.77 volts RMS; 2.2 volt peak-to-peak) almost

and can you make it adc
 
Last edited:
michael1978 said:
yes you right i just wake up,
is 1 milliwatt into a 600Ω load (about 0.77 volts RMS; 2.2 volt peak-to-peak) almost

and can you make it adc
My advice is to search the web for articles on how others have done analog to digital conversion and processed it with Arduino hardware.

For example,
https://blog.yavilevich.com/2016/08/arduino-sound-level-meter-and-spectrum-analyzer/
https://blog.yavilevich.com/2016/08/arduino-sound-level-meter-and-spectrum-analyzer/
https://www.researchgate.net/publication/275656940_Digital_sound_processing_using_arduino_and_MATLAB
https://www.researchgate.net/publication/275656940_Digital_sound_processing_using_arduino_and_MATLAB
http://www.amandaghassaei.com/projects/arduinodsp/
 
  • Like
Likes   Reactions: michael1978
Asymptotic said:
My advice is to search the web for articles on how others have done analog to digital conversion and processed it with Arduino hardware.

For example,
https://blog.yavilevich.com/2016/08/arduino-sound-level-meter-and-spectrum-analyzer/
https://www.researchgate.net/publication/275656940_Digital_sound_processing_using_arduino_and_MATLAB
http://www.amandaghassaei.com/projects/arduinodsp/
i wil like to know how work R2R dac, only with switch, or automatic digital way, because one friend of me, he told me about dac R2R ladder, but they are with switch? like this they work?
 
Asymptotic said:
No. A DAC converts digital to analog ... you probably mean an ADC (analog to digital converter).
michael1978 said:
and can you make it adc
Thread title edited. Thanks @Asymptotic :smile:
 
  • Like
Likes   Reactions: michael1978
michael1978 said:
i wil like to know how work R2R dac, only with switch, or automatic digital way, because one friend of me, he told me about dac R2R ladder, but they are with switch? like this they work?
Well, an R2R ladder DAC is just that, a DAC. Are you wanting to ask about DACs or ADCs?

It is true that some ADC architectures involve a DAC as part of the circuit, though. Is that part of what is confusing you?
 
Yes R-2R DAC is driven by a digital signal https://www.allaboutcircuits.com/textbook/digital/chpt-13/r-2r-dac/

The question that I don't know the answer to, is whether the ADC of the Arduino can sample the signal fast enough for an audio signal. Maybe Asymptotic's references will help.
 
Merlin3189 said:
Yes R-2R DAC is driven by a digital signal https://www.allaboutcircuits.com/textbook/digital/chpt-13/r-2r-dac/

The question that I don't know the answer to, is whether the ADC of the Arduino can sample the signal fast enough for an audio signal. Maybe Asymptotic's references will help.
you know i read the book arduino for musicians, and he explain audio input and audio output, so for that i ask, is possible that data from audio output to as input to adc arduino and output to dac to speaker, i know that it needs to amplify the signal because i read it to that book
 
  • #10
The Arduino does indeed use succesive approximation with a DAC to make an anolog to digital converter.
To get the 10 bits of accuracy, 13 clockcycles of the ADC clock are needed. This runs normally at 1/128 of the clock speed of the arduino, so at 125 kHz. This gives a maximum sampling frequency of 125/13 is 9.6 kHz. Not enough for quality audio. It seems you can run the ADC clock as high as 1MHz, giving a 77 kHz sampling frequency. You also have to make sure that samples are collected at very regular times, possibly with interrupts.

The input range is normally from 0V to 5V. You can use an internal 1.1V voltage reference or an external reference from 1 to 5 volts. Some amplification will be required to get the full range from an audio signal. (if you want 10 bits output)
I found lots of info here: https://www.gammon.com.au/adc
 
  • Like
Likes   Reactions: Asymptotic
  • #11
willem2 said:
The Arduino does indeed use succesive approximation with a DAC to make an anolog to digital converter.
To get the 10 bits of accuracy, 13 clockcycles of the ADC clock are needed. This runs normally at 1/128 of the clock speed of the arduino, so at 125 kHz. This gives a maximum sampling frequency of 125/13 is 9.6 kHz. Not enough for quality audio. It seems you can run the ADC clock as high as 1MHz, giving a 77 kHz sampling frequency. You also have to make sure that samples are collected at very regular times, possibly with interrupts.

The input range is normally from 0V to 5V. You can use an internal 1.1V voltage reference or an external reference from 1 to 5 volts. Some amplification will be required to get the full range from an audio signal. (if you want 10 bits output)
I found lots of info here: https://www.gammon.com.au/adc
thank you
 

Similar threads

  • · Replies 10 ·
Replies
10
Views
2K
Replies
3
Views
3K
  • · Replies 10 ·
Replies
10
Views
2K
Replies
20
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 25 ·
Replies
25
Views
4K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 3 ·
Replies
3
Views
3K
Replies
10
Views
3K
Replies
3
Views
2K