Internal speakers to audio out?

Discussion in 'General Electronics Chat' started by xxredxpandaxx, Oct 22, 2013.

  1. xxredxpandaxx

    Thread Starter New Member

    Mar 28, 2011
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    Hi I have a monitor that has internal speakers that are way to quiet, I think they are 2W if i remember correctly, and I was wondering if there was a way for me to build a simple circuit to take that signal and make an audio out jack so I can use my external speakers instead. The monitor is a HP 2709m if that helps at all.
     
  2. shteii01

    AAC Fanatic!

    Feb 19, 2010
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    Ignore the lcd monitor speakers.

    Run audio from pc to receiver. Attach speakers to receiver.
     
  3. xxredxpandaxx

    Thread Starter New Member

    Mar 28, 2011
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    Im playing my Wii U on it through HDMI.
     
  4. shteii01

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    Feb 19, 2010
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    Ok. I don't know what hookup and cables Wii U has.

    But here is what I did with my Xbox360. It has two ports. First port is HDMI. Second port is special M$ connector that has Component Video, Left and Right Audio. So. I connected HDMI to my lcd monitor, that took care of first port. I connect audio cables from second port to the receiver.
     
  5. xxredxpandaxx

    Thread Starter New Member

    Mar 28, 2011
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    it only has hdmi and a nintendo port that brakes out into rca. But im pretty sure you can't use the audio from the rca while using the hdmi. I will have to check later though. But I would still like to build the audio out jack for my monitor so that when I use my xbox 360 or the wii U I can just plug my speakers into that instead of having to connect other cords to the systems.
     
  6. shteii01

    AAC Fanatic!

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    The basic truth about those little speakers that they put into the monitors is that they are pretty worthless.

    I am surprised you want to waste your time and money on them.
     
  7. xxredxpandaxx

    Thread Starter New Member

    Mar 28, 2011
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    I don't think that we are on the same page here. I don't want to use the speakers that are in the monitor I want to build a circuit that will take the audio going to those speakers and put it to a female 3.5mm jack so that I can connect my external speakers to that jack. So basically the audio will go from the game system connected with hdmi through my monitor to the female 3.5mm jack that I want to install, then I can plug in my external speaker system with a male 3.5mm jack.
     
  8. shteii01

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    That sounds reasonable.

    How do you control the volume currently? Do you do it from Wii U?

    When you attach speakers, will those speakers have volume control on them, like the pc speakers?

    Simple plan.
    Unsolder the wires on the lcd monitor speakers. Solder them to the 3.5mm female socket.

    Less simple plan.
    Unsolder wires from the speakers. Attach them to the audio amplifier circuit. I think you probably will need two of them, one for right channel, one for left channel. Outputs of the two amplifier circuits are connected to the 3.5mm female socket. I think you use an adjustable resistor (pot?) to control the gain. I think you can use the same adjustable resistor in both amplifier circuits, so both, left and right, get amplified the same amount.
     
  9. xxredxpandaxx

    Thread Starter New Member

    Mar 28, 2011
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    There are buttons on the monitor to adjust volume, but my external speakers have a volume knob on them as well.

    I would like to have it where the internal speakers are on if there is no jack plugged in, and when you plug one in the internal speakers would no longer work. This way if I take my monitor somewhere (which I do sometimes) I will have some sound, even if it is very quiet.
     
  10. wayneh

    Expert

    Sep 9, 2010
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    I'm not sure it's relevant here, but I think part of HDMI content protection is to NOT offer an HDMI-to-analog-audio capability. So I'm not surprised the audio does not appear on the RCA jack. Even my nice Yamaha AV receiver will not pass analog audio out (other than the headphones or speakers) when the source is digital.
     
  11. shteii01

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    Feb 19, 2010
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    Ok. Since each set of speakers has its own volume control, it is best to go with the Simple Plan. The only modification you need is a way to disconnect the lcd monitor speakers when the external speakers are plugged in.

    Since you already plan to use an external 3.5mm socket, would it be ok to use some kind of switch?

    You would push or toggle the switch to disconnect the internal speakers and direct the signal to the 3.5mm socket. Then plug external speakers to the 3.5mm socket.
     
  12. wayneh

    Expert

    Sep 9, 2010
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    Many jacks have this switching capability built in.
     
  13. shteii01

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    True. But HDMI has gone through several iterations. The original design had video and audio going over the same cable. But. When they went into production, they did not implement that. I think it is HDMI 1.4 or 1.4a that finally put video and audio together. Before that you were only getting video, the audio hardware was not there.
     
  14. shteii01

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    wayne, could you link an example. I am not sure what to look for in the description when looking for one.
     
  15. wayneh

    Expert

    Sep 9, 2010
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    Like this. Or this vertical one.
     
  16. shteii01

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    Thank you.
     
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