OP Amp not amplifying audio signalHow can I integrate microphone and speaker into my microcontroller project?Regulated audio inputElectret Mic signal amplification without DC offsetAudio hack: replacing electret mic with phone audio outputWhat parameters of a real op amp determine the lowest voltage it can amplify?Audio Amplifier Circuit using op-ampMicrophone peak detector circuit no signal responseOp Amp Not WorkingActive Filter and Sine to Square Conversion IssuesReplacing Electret Microphone with Dynamic in Velleman Voice Changer Circuit
Does Dispel Magic work on Tiny Hut?
Do creatures with a speed 0ft., fly 30ft. (hover) ever touch the ground?
Standard deduction V. mortgage interest deduction - is it basically only for the rich?
Machine learning testing data
What is an equivalently powerful replacement spell for Yuan-Ti's Suggestion spell?
How to prevent "they're falling in love" trope
Where would I need my direct neural interface to be implanted?
How could indestructible materials be used in power generation?
What does the same-ish mean?
Should I tell management that I intend to leave due to bad software development practices?
Why is the sentence "Das ist eine Nase" correct?
Send out email when Apex Queueable fails and test it
How obscure is the use of 令 in 令和?
How to compactly explain secondary and tertiary characters without resorting to stereotypes?
Label inside tikzcd square
Is it possible to map the firing of neurons in the human brain so as to stimulate artificial memories in someone else?
When handwriting 黄 (huáng; yellow) is it incorrect to have a disconnected 草 (cǎo; grass) radical on top?
How seriously should I take size and weight limits of hand luggage?
How to stretch the corners of this image so that it looks like a perfect rectangle?
Mathematica command that allows it to read my intentions
How to travel to Japan while expressing milk?
Notepad++ delete until colon for every line with replace all
How dangerous is XSS
What's the meaning of "Sollensaussagen"?
OP Amp not amplifying audio signal
How can I integrate microphone and speaker into my microcontroller project?Regulated audio inputElectret Mic signal amplification without DC offsetAudio hack: replacing electret mic with phone audio outputWhat parameters of a real op amp determine the lowest voltage it can amplify?Audio Amplifier Circuit using op-ampMicrophone peak detector circuit no signal responseOp Amp Not WorkingActive Filter and Sine to Square Conversion IssuesReplacing Electret Microphone with Dynamic in Velleman Voice Changer Circuit
$begingroup$
Hi, part of my project requires me to amplify an audio signal coming from an electret condenser microphone which outputs an average of 10mVpp to approximately 2.5Vpp. I Used two cascaded non-inverting TL071 OP-amps since one Op-amp doesn't have enough GBW. The output of the mic is low-pass filtered with a cut-off frequency of around 13kHz.
It works perfectly if I input a signal from the signal generator, the output is as required, however with the signal from the microphone there is no output, just a DC offset which is coupled by the capacitor at the end. I also tried buffering the output form the mic.
Any help would be much appreciated.
EDIT:
Didn't realize the error in the schematic, resistor 1k should be between mic and 5V.
operational-amplifier amplifier audio
asked 4 hours ago
SimonSimon
304
$endgroup$
add a comment |
$begingroup$
Hi, part of my project requires me to amplify an audio signal coming from an electret condenser microphone which outputs an average of 10mVpp to approximately 2.5Vpp. I Used two cascaded non-inverting TL071 OP-amps since one Op-amp doesn't have enough GBW. The output of the mic is low-pass filtered with a cut-off frequency of around 13kHz.
It works perfectly if I input a signal from the signal generator, the output is as required, however with the signal from the microphone there is no output, just a DC offset which is coupled by the capacitor at the end. I also tried buffering the output form the mic.
Any help would be much appreciated.
EDIT:
Didn't realize the error in the schematic, resistor 1k should be between mic and 5V.
operational-amplifier amplifier audio
asked 4 hours ago
SimonSimon
304
$endgroup$
$begingroup$
Is the 1 kohm part at the left of the diagram part of your circuit or part of your model for the microphone? Is it also used when you connect the function generator?
$endgroup$
– The Photon
3 hours ago
$begingroup$
JRE's answer was the solution. You're right about the 1k, my mistake. I edited it
$endgroup$
– Simon
3 hours ago
add a comment |
$begingroup$
Hi, part of my project requires me to amplify an audio signal coming from an electret condenser microphone which outputs an average of 10mVpp to approximately 2.5Vpp. I Used two cascaded non-inverting TL071 OP-amps since one Op-amp doesn't have enough GBW. The output of the mic is low-pass filtered with a cut-off frequency of around 13kHz.
It works perfectly if I input a signal from the signal generator, the output is as required, however with the signal from the microphone there is no output, just a DC offset which is coupled by the capacitor at the end. I also tried buffering the output form the mic.
Any help would be much appreciated.
EDIT:
Didn't realize the error in the schematic, resistor 1k should be between mic and 5V.
operational-amplifier amplifier audio
asked 4 hours ago
SimonSimon
304
$endgroup$
Hi, part of my project requires me to amplify an audio signal coming from an electret condenser microphone which outputs an average of 10mVpp to approximately 2.5Vpp. I Used two cascaded non-inverting TL071 OP-amps since one Op-amp doesn't have enough GBW. The output of the mic is low-pass filtered with a cut-off frequency of around 13kHz.
It works perfectly if I input a signal from the signal generator, the output is as required, however with the signal from the microphone there is no output, just a DC offset which is coupled by the capacitor at the end. I also tried buffering the output form the mic.
Any help would be much appreciated.
EDIT:
Didn't realize the error in the schematic, resistor 1k should be between mic and 5V.
operational-amplifier amplifier audio
operational-amplifier amplifier audio
asked 4 hours ago
SimonSimon
304
asked 4 hours ago
SimonSimon
304
edited 3 hours ago
Simon
asked 4 hours ago
SimonSimon
304
asked 4 hours ago
SimonSimon
304
asked 4 hours ago
SimonSimon
304
304
$begingroup$
Is the 1 kohm part at the left of the diagram part of your circuit or part of your model for the microphone? Is it also used when you connect the function generator?
$endgroup$
– The Photon
3 hours ago
$begingroup$
JRE's answer was the solution. You're right about the 1k, my mistake. I edited it
$endgroup$
– Simon
3 hours ago
add a comment |
$begingroup$
Is the 1 kohm part at the left of the diagram part of your circuit or part of your model for the microphone? Is it also used when you connect the function generator?
$endgroup$
– The Photon
3 hours ago
$begingroup$
JRE's answer was the solution. You're right about the 1k, my mistake. I edited it
$endgroup$
– Simon
3 hours ago
$begingroup$
Is the 1 kohm part at the left of the diagram part of your circuit or part of your model for the microphone? Is it also used when you connect the function generator?
$endgroup$
– The Photon
3 hours ago
$begingroup$
Is the 1 kohm part at the left of the diagram part of your circuit or part of your model for the microphone? Is it also used when you connect the function generator?
$endgroup$
– The Photon
3 hours ago
$begingroup$
JRE's answer was the solution. You're right about the 1k, my mistake. I edited it
$endgroup$
– Simon
3 hours ago
$begingroup$
JRE's answer was the solution. You're right about the 1k, my mistake. I edited it
$endgroup$
– Simon
3 hours ago
add a comment |
1 Answer
1
active
oldest
votes
$begingroup$
Put a large resistor from the + input of the left opamp to ground. Say, like 470kohm.
The DC bias from the microphone is getting through to the opamp. The TL071 has very high impedance inputs. The tiny bit of DC that leaks through the first capacitor is enough to push that input away from 0V. The amplification then drives the output to one of the rails.
Just noticed something else.
The microphone bias is messed up.
You need that 1k resistor between the microphone and 5V
As you've got it, the microphone is trying to pull the 5V source up and down in response to the sound.
Best case, it doesn't work.
Worst case, you've killed the microphone.
answered 4 hours ago
JREJRE
22.9k53875
$endgroup$
2
$begingroup$
Could be bias current from the op amp itself that saturates the caps -- there is no DC path for the bias current. This is less likely, as it works with a function generator.
$endgroup$
– Scott Seidman
4 hours ago
$begingroup$
Thank you so much! I realized there was a problem with the small dc leak from the beginning, I couldn't figure out a way to eliminate it completely. Now it works !!
$endgroup$
– Simon
3 hours ago
$begingroup$
Thanks for pointing out the error on the schematic, it was correctly implemented on the breadboard
$endgroup$
– Simon
3 hours ago
add a comment |
Your Answer
StackExchange.ifUsing("editor", function ()
return StackExchange.using("mathjaxEditing", function ()
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix)
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["\$", "\$"]]);
);
);
, "mathjax-editing");
StackExchange.ifUsing("editor", function ()
return StackExchange.using("schematics", function ()
StackExchange.schematics.init();
);
, "cicuitlab");
StackExchange.ready(function()
var channelOptions =
tags: "".split(" "),
id: "135"
;
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function()
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled)
StackExchange.using("snippets", function()
createEditor();
);
else
createEditor();
);
function createEditor()
StackExchange.prepareEditor(
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader:
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
,
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
);
);
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2felectronics.stackexchange.com%2fquestions%2f430375%2fop-amp-not-amplifying-audio-signal%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
Put a large resistor from the + input of the left opamp to ground. Say, like 470kohm.
The DC bias from the microphone is getting through to the opamp. The TL071 has very high impedance inputs. The tiny bit of DC that leaks through the first capacitor is enough to push that input away from 0V. The amplification then drives the output to one of the rails.
Just noticed something else.
The microphone bias is messed up.
You need that 1k resistor between the microphone and 5V
As you've got it, the microphone is trying to pull the 5V source up and down in response to the sound.
Best case, it doesn't work.
Worst case, you've killed the microphone.
answered 4 hours ago
JREJRE
22.9k53875
$endgroup$
2
$begingroup$
Could be bias current from the op amp itself that saturates the caps -- there is no DC path for the bias current. This is less likely, as it works with a function generator.
$endgroup$
– Scott Seidman
4 hours ago
$begingroup$
Thank you so much! I realized there was a problem with the small dc leak from the beginning, I couldn't figure out a way to eliminate it completely. Now it works !!
$endgroup$
– Simon
3 hours ago
$begingroup$
Thanks for pointing out the error on the schematic, it was correctly implemented on the breadboard
$endgroup$
– Simon
3 hours ago
add a comment |
$begingroup$
Put a large resistor from the + input of the left opamp to ground. Say, like 470kohm.
The DC bias from the microphone is getting through to the opamp. The TL071 has very high impedance inputs. The tiny bit of DC that leaks through the first capacitor is enough to push that input away from 0V. The amplification then drives the output to one of the rails.
Just noticed something else.
The microphone bias is messed up.
You need that 1k resistor between the microphone and 5V
As you've got it, the microphone is trying to pull the 5V source up and down in response to the sound.
Best case, it doesn't work.
Worst case, you've killed the microphone.
answered 4 hours ago
JREJRE
22.9k53875
$endgroup$
2
$begingroup$
Could be bias current from the op amp itself that saturates the caps -- there is no DC path for the bias current. This is less likely, as it works with a function generator.
$endgroup$
– Scott Seidman
4 hours ago
$begingroup$
Thank you so much! I realized there was a problem with the small dc leak from the beginning, I couldn't figure out a way to eliminate it completely. Now it works !!
$endgroup$
– Simon
3 hours ago
$begingroup$
Thanks for pointing out the error on the schematic, it was correctly implemented on the breadboard
$endgroup$
– Simon
3 hours ago
add a comment |
$begingroup$
Put a large resistor from the + input of the left opamp to ground. Say, like 470kohm.
The DC bias from the microphone is getting through to the opamp. The TL071 has very high impedance inputs. The tiny bit of DC that leaks through the first capacitor is enough to push that input away from 0V. The amplification then drives the output to one of the rails.
Just noticed something else.
The microphone bias is messed up.
You need that 1k resistor between the microphone and 5V
As you've got it, the microphone is trying to pull the 5V source up and down in response to the sound.
Best case, it doesn't work.
Worst case, you've killed the microphone.
answered 4 hours ago
JREJRE
22.9k53875
$endgroup$
Put a large resistor from the + input of the left opamp to ground. Say, like 470kohm.
The DC bias from the microphone is getting through to the opamp. The TL071 has very high impedance inputs. The tiny bit of DC that leaks through the first capacitor is enough to push that input away from 0V. The amplification then drives the output to one of the rails.
Just noticed something else.
The microphone bias is messed up.
You need that 1k resistor between the microphone and 5V
As you've got it, the microphone is trying to pull the 5V source up and down in response to the sound.
Best case, it doesn't work.
Worst case, you've killed the microphone.
answered 4 hours ago
JREJRE
22.9k53875
edited 3 hours ago
answered 4 hours ago
JREJRE
22.9k53875
answered 4 hours ago
JREJRE
22.9k53875
answered 4 hours ago
JREJRE
22.9k53875
22.9k53875
2
$begingroup$
Could be bias current from the op amp itself that saturates the caps -- there is no DC path for the bias current. This is less likely, as it works with a function generator.
$endgroup$
– Scott Seidman
4 hours ago
$begingroup$
Thank you so much! I realized there was a problem with the small dc leak from the beginning, I couldn't figure out a way to eliminate it completely. Now it works !!
$endgroup$
– Simon
3 hours ago
$begingroup$
Thanks for pointing out the error on the schematic, it was correctly implemented on the breadboard
$endgroup$
– Simon
3 hours ago
add a comment |
2
$begingroup$
Could be bias current from the op amp itself that saturates the caps -- there is no DC path for the bias current. This is less likely, as it works with a function generator.
$endgroup$
– Scott Seidman
4 hours ago
$begingroup$
Thank you so much! I realized there was a problem with the small dc leak from the beginning, I couldn't figure out a way to eliminate it completely. Now it works !!
$endgroup$
– Simon
3 hours ago
$begingroup$
Thanks for pointing out the error on the schematic, it was correctly implemented on the breadboard
$endgroup$
– Simon
3 hours ago
2
2
$begingroup$
Could be bias current from the op amp itself that saturates the caps -- there is no DC path for the bias current. This is less likely, as it works with a function generator.
$endgroup$
– Scott Seidman
4 hours ago
$begingroup$
Could be bias current from the op amp itself that saturates the caps -- there is no DC path for the bias current. This is less likely, as it works with a function generator.
$endgroup$
– Scott Seidman
4 hours ago
$begingroup$
Thank you so much! I realized there was a problem with the small dc leak from the beginning, I couldn't figure out a way to eliminate it completely. Now it works !!
$endgroup$
– Simon
3 hours ago
$begingroup$
Thank you so much! I realized there was a problem with the small dc leak from the beginning, I couldn't figure out a way to eliminate it completely. Now it works !!
$endgroup$
– Simon
3 hours ago
$begingroup$
Thanks for pointing out the error on the schematic, it was correctly implemented on the breadboard
$endgroup$
– Simon
3 hours ago
$begingroup$
Thanks for pointing out the error on the schematic, it was correctly implemented on the breadboard
$endgroup$
– Simon
3 hours ago
add a comment |
Thanks for contributing an answer to Electrical Engineering Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2felectronics.stackexchange.com%2fquestions%2f430375%2fop-amp-not-amplifying-audio-signal%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
$begingroup$
Is the 1 kohm part at the left of the diagram part of your circuit or part of your model for the microphone? Is it also used when you connect the function generator?
$endgroup$
– The Photon
3 hours ago
$begingroup$
JRE's answer was the solution. You're right about the 1k, my mistake. I edited it
$endgroup$
– Simon
3 hours ago