LM741 Op Amp

Discussion in 'General Electronics Chat' started by Bill Holben, Feb 17, 2012.

  1. Bill Holben

    Thread Starter New Member

    Feb 12, 2012
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    Can anyone please let me where I can find simple schematics for a LM741 Stereo MP3 amplifier with great sound. Thank You.
     
  2. MrChips

    Moderator

    Oct 2, 2009
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    Well, sooner or later Audioguru is going to come by and tell you to scrap the ol' 44-year old 741 op amp and get something modern.
     
  3. Wendy

    Moderator

    Mar 24, 2008
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    The fact is the old op amp has many uses, but audio is too fast for it. You could go with a TL074, which is 4 more modern op amps in a DIP package.

    All the same op amp theories apply. The LM741 is an excellent teaching tool, but not the best part in the bin for general purpose work.

    Are you wanting simple amplifier schematics? What kind of gain do you think you need?
     
  4. bountyhunter

    Well-Known Member

    Sep 7, 2009
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    There is no such thing as any type of audio amp using a 741 that has great sound.

    I agree with the choice of TLO74/TLO84 for audio amps processing line level signals. LF356 is also decent.
     
  5. Wendy

    Moderator

    Mar 24, 2008
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    I can draw up something if you want. I will not have tested it of course, but it is pretty basic. You are wanting to drive some headphones?

    Audio Guru is pretty good with this stuff. Since you mentioned a 741 (which he hates with a passion) I expect he'll be around shortly.
     
  6. R!f@@

    AAC Fanatic!

    Apr 2, 2009
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    Bill.....Keep it down. AG mind be near by.
     
  7. Audioguru

    New Member

    Dec 20, 2007
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    Since his teacher asked him to use a lousy old 741 opamp then I guess he will use it.

    What will the opamp be used for? An MP3 player already has an excellent output.

    Oh. This is his 3rd thread about an audio power amplifier.
    First he asked about a low power LM386 power amplifier, then a TEA2025 amplifier that he could not make work.
     
  8. Bill Holben

    Thread Starter New Member

    Feb 12, 2012
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    Ok everyone. Like I said before, let's start fresh. What are some of the modern, up to date amps that i can get. This is going to be a cell phone I will be using. I will be using two 6watt speakers. I am going to be using this on my bicycle so I want it to be loud with good sound. It will be powered by nine volts.Remember I am new at all this and I am learning as I go.
    I appreciate everyones help. Please keep it coming.
     
  9. debjit625

    Well-Known Member

    Apr 17, 2010
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    Why don't you use an audio amplifier IC like TBA820 the simplest one I can think of.
    Download the datasheet from STMicroelectronics,inside it you will find the circuit diagram.

    Good Luck
     
  10. Audioguru

    New Member

    Dec 20, 2007
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    A little 9V battery can supply about 400mA for a few minutes. After about 10 minutes its voltage has dropped to only 7V and it is close to being dead.
    Then its average power is 8V x 0.4A= 3.2W.

    Most simple audio amplifiers produce heat in addition to output power so when the total power is 3.2W then the heating is 1.28W and the total sound power is only 1.92W.
    Only 1W per channel from a stereo amp is not loud.

    An ordinary audio amplifier like an LM386 produces only 0.45W into an 8 ohm speaker when the battery is 9V and its output power drops to 0.28W when the battery has dropped to 7V.

    A TBA820 audio amplifier IC produces 1W in an 8 ohm speaker when a 9V battery is new and the power drops to about 0.64W when the battery has dropped to 7V. Its distortion is fairly high.
     
  11. Wendy

    Moderator

    Mar 24, 2008
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    When I hear MP3 I tend to assume earphones. What I'm reading says speakers. So which is it?
     
  12. Audioguru

    New Member

    Dec 20, 2007
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    In another thread he said he made a TEA2025 power amplifier that did not work.
    In this thread he wants to use a 741 opamp as a power amplifier to drive his speakers, but it also will not work because it cannot drive a speaker.
    He also wants to power this stereo power amplifier from a little 9V battery.
     
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