4000hz signal waveform doubt.

[imraneesa]

I am having gemini house loudspeaker RS415. When treble increase i am hearing plenty scrathy noise. I used 4000hz signal and i am attaching the waveform for any advice. The signal is good until it reach last opamp after that it goes as shown in the figure.

 

[anatech]

Hi imraneesa,
Try to reduce the signal level until you see a sine wave that isn't clipped.

-Chris

 

[imraneesa]

Hi imraneesa,
Try to reduce the signal level until you see a sine wave that isn't clipped.

-Chris

if i reduce treble it is playing good. so we have to set the treble until we dont hear scratchy noise? how treble works?

 

[anatech]

Hi imraneesa,

if i reduce treble it is playing good.

Bingo! That's the answer.

so we have to set the treble until we dont hear scratchy noise?

The peak level must be low enough so it doesn't clip. I would imagine the midrange and bass are also clipping if the highs are.

how treble works?

I don't understand your question. The treble parts of music is just a signal like everything else. Treble is normally a much lower power level, so the levels shouldn't be clipped compared to the bass or midrange outputs. The clipped output shown of the oscilloscope screen looks like it is about 32 Vp-p. (reading is 31.6 Vp-p on the screen) That hints of a +/- 16~17 volt power supply voltage for the op amps, maybe a touch higher. If this is a preamp output, you need an amplifier with more gain. I would need a picture of how your system looks (signal flow type).

-Chris