In simulation I decrease the value of R3 to even 1K but I still have that distortions on the out put
http://www.mypicx.com/thumb/872785171_03022011_1.jpg
An externally hosted image should be here but it was not working when we last tested it.
http://www.mypicx.com/thumb/872785171_03022011_1.jpg
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but this picture is from Sony low pass filter
Look, this is with its highest value of Level potentiometer
the higher signal is the output signal and the lower is the input signal in 100Hz
I used Multimeter in Work Bench to measure the db and in highest value of level potentiometer it's about 6.576 db
and in the lowest value of Level pot it's about -133.667 db
That EMI is partly why C1 is in the circuit. THe 4558 and TL072 are 3 MHz chips, while the TL062 is only a 1 Mz device. Makes send that you had more emi issues with them. Imagine what could happen with really fast chip.
Another reason for EMI susceptibility could be that your power supply pins are not bypassed close enough to the chip. C2 and C6 should be right at the chip pin and connected directly to ground.
Is the buzz at mains frequency or twice mains frequency? Guessing that you have 50 Hz mains, then 50 or 100 Hz. If 50 Hz it is likely a ground loop or more EMI. If 120 Hz, you have PSU noise. To me, mains frequencies sound like a hum, psu ripple sounds like a buzz. The issue is how the circuit was built or connected, not the circuit topology.
Are the amp and filter in the same metal case? Do all grounds run to a common point?
Some DMM's have the ability to measure caps, or there are dedicated LCR meters.
Your scope picture links don't work
Another reason for EMI susceptibility could be that your power supply pins are not bypassed close enough to the chip. C2 and C6 should be right at the chip pin and connected directly to ground.
Is the buzz at mains frequency or twice mains frequency? Guessing that you have 50 Hz mains, then 50 or 100 Hz. If 50 Hz it is likely a ground loop or more EMI. If 120 Hz, you have PSU noise. To me, mains frequencies sound like a hum, psu ripple sounds like a buzz. The issue is how the circuit was built or connected, not the circuit topology.
Are the amp and filter in the same metal case? Do all grounds run to a common point?
Some DMM's have the ability to measure caps, or there are dedicated LCR meters.
Your scope picture links don't work
First box picture that didn't work :
http://rapidshare.com/files/450614425/First_picture_from_my_present_Filter.JPG
Second box picture :
http://rapidshare.com/files/450614523/Second_picture_from_Sony_filter.JPG
http://rapidshare.com/files/450614425/First_picture_from_my_present_Filter.JPG
Second box picture :
http://rapidshare.com/files/450614523/Second_picture_from_Sony_filter.JPG
I reduce the all equalizer's controllers level on my Winamp and my motherboard's card sound but that buzz didn't stop
I think the problem is from my two sub(s)(because of increasing the amplifier's sound ( to a lot more than sub(s) power)
Is it possible?
I think the problem is from my two sub(s)(because of increasing the amplifier's sound ( to a lot more than sub(s) power)
Is it possible?
That looks like clipping - I suspect that you are over driving the second stage. take a look at the output of the first opamp (where it connects to R6). Is that clean but amplified?
This has nothing to do with the buzz that you hear in the real thing, however.
This has nothing to do with the buzz that you hear in the real thing, however.
You're connecting to a computer. You said that. Homer Simpson moment - DOH!
The Buzz is probably related to the computer power supply infecting the ground. Is the filter quiet when not hooked to the computer? Try it with an MP3 player or if your computer is a laptop, run it on batteries.
The Buzz is probably related to the computer power supply infecting the ground. Is the filter quiet when not hooked to the computer? Try it with an MP3 player or if your computer is a laptop, run it on batteries.
Hmm. The data sheet says that that the TL062 is able to swing 10V on 15V rails. I think it is a simulation issue. Simulator rails at 12V or something less? Circuit accurately depicted?
OK, so your problem is ground loop or PSU noise. Using your voltmeter on the AC setting measure the AC voltage between each power supply rail and ground.
Sim model looks OK, but since we have a real thing, let's work on that.
Sim model looks OK, but since we have a real thing, let's work on that.
I use a a transformer with three separate coil
36 V double ( 70 V with center point ) ( my amplifier's voltage )
12 V double ( my filter's voltage )
and a 4V
I measure the AC value of two ground ( Two center ) of this trans and it was from 0-5 to 1V
36 V double ( 70 V with center point ) ( my amplifier's voltage )
12 V double ( my filter's voltage )
and a 4V
I measure the AC value of two ground ( Two center ) of this trans and it was from 0-5 to 1V
By saying the measuring of this trans, I mean the two center point of my amplifier's Voltage and my filter's
I don't follow what you measured. Connect your voltmeter black lead to ground and measure the AC voltage at the spots marked +12V and -12V on your filter schematic.
Can you post pictures of your grounding arrangements?
Can you post pictures of your grounding arrangements?
you mean the board of filter that in the moment is connected to my amp or the one that I simulated with Work bench???
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