Audio Spectrum Graphic display project

Thread Starter

lubnaan90

Joined Jan 13, 2010
198
Hello to all ,

This post is especially a Thanks giving post to the Users of this forum, who helped me in my project "Audio Spectrum Graphic display", which after a duration of month in development has finally come to an end with successful results .

Thanks to :

BERTUS, for helping me with PSU units for my projects , also for helping me with transistors to be used in Digital (controller) circuit.

AUDIOGURU & SGTWOOKIE, For helping me with Selecting the right Transistors for my project.

Here are the links if anyone wishes to see a video clip of my project.

http://www.youtube.com/watch?v=Jw3MOZVG60M

http://www.facebook.com/video/video.php?v=106387059388489
 
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bertus

Joined Apr 5, 2008
22,270
Hello,

It looks nice.
How is the transformer holding?
I see you power both boards with the powersupply.
Can you measure the currents in each powersupply connection to the boards?
(the two +12 Volts and the - 12 Volts).
The total current may not be larger as the transformer current.

Greetings,
Bertus
 

Thread Starter

lubnaan90

Joined Jan 13, 2010
198
Hello,

It looks nice.
How is the transformer holding?
I see you power both boards with the powersupply.
Can you measure the currents in each powersupply connection to the boards?
(the two +12 Volts and the - 12 Volts).
The total current may not be larger as the transformer current.

Greetings,
Bertus
Hello,
Thank you for your comment,
The transformer seems to be holding fine.
Yes i have powered both the boards with a single Transformer (just like you suggested in the schematic).
At first i tried using a separate Wall DC adapter (along with the regulator) for the Controller , then thought to experiment with single transformer for both boards, I did not notice a difference (dim Lights) in the Display using single Transformer. transformer is not overloading & not heating at all .

About measuring the current , my multimeter for some reason doesn't show current , even though it has the function of checking current (probably because its Chinese) :)
 

bertus

Joined Apr 5, 2008
22,270
Hello,

Some multimeters have seperate connections for the current measurement.
The minus will stay on the normal position the plus connecttion may have an other connection to measure currents.
Perhaps the manual of the meter will tell.

Greetings,
Bertus
 

Audioguru

Joined Dec 20, 2007
11,248
I am glad that you got it working well but the sound quality on your videos is horrible.
There are no deep bass frequencies and your spectrum analyser proves it.
Maybe music in your country has no deep bass frequencies?
 

Thread Starter

lubnaan90

Joined Jan 13, 2010
198
I am glad that you got it working well but the sound quality on your videos is horrible.
There are no deep bass frequencies and your spectrum analyser proves it.
Maybe music in your country has no deep bass frequencies?
Hello ,

Thank you for your comment ,
As a matter of fact , i did not make a stereo to mono circuit for the OPAMP .
The Spectrum analyzer is only using Audio signal from left channel of an stereo output & the soundtrack in the video is probably having most of the deep bass frequency in the right channel .
The video was shot from an ordinary digital camera, thats why the sound quality is not good. I'll soon make some modifications in the circuit & upload a better video with less horrible sound quality.
 

Audioguru

Joined Dec 20, 2007
11,248
Deep bass frequencies are almost always in mono so that both woofers play them.
Maybe the video camera has a "speech filter" so that everything sounds tinny (no bass) and muffled like a telephone.

EDIT:
Wait a minute. The audio spectrum analyser project is the one written partially in Vietnamese isn't it? Then its lowest frequency column of LEDs show the 32Hz octave from 24Hz to 48Hz. Those LEDs do not respond in the video so the sound source that is playing the music has no deep bass frequencies and the camera shows it.
 
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Thread Starter

lubnaan90

Joined Jan 13, 2010
198
Deep bass frequencies are almost always in mono so that both woofers play them.
Maybe the video camera has a "speech filter" so that everything sounds tinny (no bass) and muffled like a telephone.

EDIT:
Wait a minute. The audio spectrum analyser project is the one written partially in Vietnamese isn't it? Then its lowest frequency column of LEDs show the 32Hz octave from 24Hz to 48Hz. Those LEDs do not respond in the video so the sound source that is playing the music has no deep bass frequencies and the camera shows it.
Hello,

Yes, You are absolutely correct , this project is the one in Vietnamese.
 
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