Modified lepy LP-A6fm amp

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When I brought lepy LP-A6fm from my local store(Thailand) for under 10 $.  I though it's a good low-cost amp and I've found that this amp not bad at all. The bad thing I hate LP-A6fm is the amp have big pop noise when connecting to the power supply to the amplifier and the amplifier doesn't have any on/off switch. I thought the problem may come from JRC 4558 op-amp that doesn't have soft on/off function so I decided to change JRC 4558 to ne5532 op amp for low pop noise and change some capacitors for sound quality improvement.

 Yeah! Let's start.


List of component:

1 x ne5532 opamp and 8 pins ic socket (for JRC 4558 op amp replacement, sound improve much).
3 x capacitor 100 uf muse FW(FG are better) for op amp power supply replacement and for main amp replacement
4 x 10 uf Elna Ccerafine or Silmic II electrolytic capacitors for the mellower sound.
1 mks 0.1 uf Wima capacitor(not see in the video because it attaches to preamp power supply under PCB board.
2 x 1000 uf/25 volts Elna(you can find better capacitor but for under 10$ amp you can think twice).

 For the further upgrade, you can change power amp ic (TDA 7294 for 15 watts stereo power) too,but I'm okay with the amp now.

This video will show you lepy LP-A6fm modified for better sound and eliminated pop noise when power on/off

 See non-modified lepy LP-A6fm for comparison

Comments

  1. Owais Khan5/19/16, 2:08 AM

    This comment has been removed by a blog administrator.

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  2. esw5/19/16, 7:01 AM

    Please not spam your link.

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