Your link to Facebook does not work. Please post the PNG schematic here with your reply, not at Facebook.

 

Oh I see. Hope this will work. The design uses a mosfet to increase the current and is said that it can power even hundreds of LEDs with the right mosfet.

 

Oh I see. Hope this will work. The design uses a mosfet to increase the current and is said that it can power even hundreds of LEDs with the right mosfet.

It is a garbage circuit designed by a little kid who knows NOTHING about electronics:
1) The opamp has no negative feedback so it has a gain of 200,000 (or more) from DC to 4Hz then its gain slowly drops at higher frequencies.
2) The 10k pot does absolutely nothing.
3) The Mosfet will be turned on all the time.

Here is a gain vs frequency graph of a lousy old 741 opamp when it has no negative feedback:

 

A MOSFET can operate in the linear region, but they rarely do so, for a reason. Thier best use is in the on/off modes. A BJT, on the other hand, is much more linear over a wider range.

If you keep frustrating AG he is going to have a heart attack! He is an old retired audio engineer with lots of experience and little patience. The original schematic he showed you would work.

Judging solely from your lack of understanding of resistors and LEDs I would place you as a beginner. This is OK, we like beginners, and have no problem working through issues.

Are you inventing these schematics, or are you pulling them from some other source?

If you let us know what you are really trying to achieve the odds go way up we can get you were you want to go.

The link I have provided on post #19 will get you to high quantities of LEDs responding to sound, but I suspect you have blown them off hoping for a shortcut. Electronics rarely offers shortcuts, you have to do your research, which means reading. Many times trying to save one too few parts also gets you into trouble.

AAC offers local hosting of pictures (IE, schematics) and albums, there is a reason for this. If you need help in learning how to do this we'll teach you. It is one of those things that will help you forever.

I am one of the draftsmen and designers on this site, but you have to communicate both ways. That is just the way it is.

If you have patience we'll get there.

 

Hello,

Here is a sound-to-light circuit I made with Fenris.
It uses the speaker output from an amplifier.

It consists of an evelope detector, a schmitt-trigger and a lampdriver.

Bertus

 

Note: in Fenris's schematic he is talking incandescent bulbs (light bulbs). If you choose to use LEDs you will still need resistors.

 

If you keep frustrating AG he is going to have a heart attack! He is an old retired audio engineer with lots of experience and little patience.

Hee, hee.
I already had a very bad heart attack 3 years ago. I got to the hospital quickly and they fixed two blocked arteries that feed my heart (I felt the warmth of the radioactivity so the doctor and I could see what he was doing) so now I am better than new.

 

Yes I will stick to AG's original circuit, sorry for the trouble by the way.

Yes, I don't know how to use the site's photo hosting. Please do assist me with this problem.

The schematics that I post here are from other sources. I have been searching the internet for weeks just to find a perfect circuit: a circuit which lights a few LEDs (at least 2!) when it detects a sound from a mic and is powered by a 9V source. I don't know why I'm having such a difficulty finding one.

I'm just having troubles on the electret microphone. We got 4 new mics and only one of them worked for the circuit. I don't know why I can't make the others work.

 

You can use the Velleman MK-103 kit or build your own from their schematic.

 

How to Upload an Attachment

To attach a document or picture to a post

Click "Go Advanced" at the bottom of your post,

One of several options will pop up,

Click "Manage Attachments" much further at the bottom of your post,

To upload a file from your computer click "Browse", then select the file.

Schematics should be .gif or .png format, pictures should be .jpg. .jpg formats will fuzz out schematics, and should not be used for that purpose.

---------------

If you want to display this file there is an old thread I made,

How to Display Attachments Full Size

 

Just checked out the Velleman kit for Sound to LED. I attached the schematic so that everyone could see. Pretty sure this will work since it's available in the market. I'm confused though with what the 1M5 resistor is.. Is that just a 1Meg ohm resistor?

 

Just checked out the Velleman kit for Sound to LED. I attached the schematic so that everyone could see. Pretty sure this will work since it's available in the market. I'm confused though with what the 1M5 resistor is.. Is that just a 1Meg ohm resistor?

The 1M5 resistor is 1.5 mega ohm. That is one way that people use to show the decimal point of a value of an item in schematics. 1K5 is 1.5K, 1R5 would be 1.5 and so on

 

The Velleman kit uses four 2.0V red LEDs. They can be replaced with two 3.5V white or blue LEDs. The LEDs will soon begin dimming then turn off as the battery voltage runs down.

 

Of course, you could always use D cells in series, and delay the inevitable.

Yes, I am stirring.