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I got this amp. Now at large volumes, there seems to be clipping. How can I prevent it from happening, rather than never playing at high vol.

Can it be done by AGC or Dynamic Range Compression or Noise Gate.

In my case, which is a ready made pcb, how can I include such circuitry. Is it even possible.

Also, while selecting an IC, what needs to be looked at that will suggest clipping would not happen, or which parts needs to be referenced from the datasheet which ensures preventing clipping.

At large volumes, if I disconnect the mp3 player from the amp but keep the jack plugged into the amp, a high hum is heard. When removed, hum is lowered but not eliminated. Similarly, when track changes. What steps needs to be taken to eliminate them.

All the time before actually getting into practical electronics, I was only looking at Power output, THD+N, Class, etc of amplifier. It is only after going hands-on, for the first time, that I can experience the real things which most matter.

Appreciate for helping me become a pro.

Thanks.

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closed as off-topic by Leon Heller, Matt Young, Daniel Grillo, Joe Hass, placeholder May 22 '14 at 15:39

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "Questions on the use of electronic devices are off-topic as this site is intended specifically for questions on electronics design." – Leon Heller, Daniel Grillo, Joe Hass
If this question can be reworded to fit the rules in the help center, please edit the question.

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Class D amps are extremely susceptible to hum on the power feeds to the amplifier. This is because the MOSFETs that do the switching are switching hard against the power rails and any AC voltage superimposed on these rails (ripple aka hum) gets transferred to the speaker.

Best idea is to add more decoupling capacitors to the power supply that feeds the class D amplifier. Regards using a compressor, yes that would work but you will likely lose some dynamics of your sound when played at more moderate levels - can you tolerate this?

The mp3 player lead - this sounds like the normal situation you would get an any amplifier that uses an unbalanced input amplifier (as most are).

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  • \$\begingroup\$ I have not completely understood dynamic range. Also, the amp is 20w but the speaker is rated for 25w. Still there is clipping. Why? \$\endgroup\$ – arjun May 22 '14 at 12:43
  • \$\begingroup\$ In music, although the overall sound may only be moderately loud, there will be short-duration peaks that will be affected by the use of a compressor. Such as from kick drums - the compressor will probably still "ruin" these and the perceived quality of the resultant sound will be "having less dynamics". Clipping has nothing to do with the speaker. \$\endgroup\$ – Andy aka May 22 '14 at 13:05
  • \$\begingroup\$ alright. something makes sense now. so how can i ensure that the max gain listed for my amp, 29.5dB, is never exceeded. Coz the supply wch i provide is only 8V, less than the max-14v. And clipping is occurring when i put the pot and player vol at max. Wonder what will happen if i supply close to 14V. For a start, what cud be the basic way whereby the input signal never reaches a condition, in relation to the supply voltage, where it will exceed the max gain. \$\endgroup\$ – arjun May 22 '14 at 17:54

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