My motherboard is too quiet.

[gilly1984]

How can i increase the volume

I have adjusted all setting to their loudest but i am still not satisfied.

I tried building a headphone amp but blew the opamp.

Is it better to have hd audio on or ac97 for loudness? I can change it in the bios.

[mariushm]

Re: My motherboard is too quiet.

It makes no difference if you have hd audio or ac97 selected in bios.

That's simply an option related to the type of connector your computer case uses to connect microphone and headphone jacks on the computer case to the motherboard.

Make sure you don't have loudness equalization or other options checked.. in windows 7 : right click on the speaker icon, select playback devices, select your speakers , properties, see the "Levels" tab and what's selected in the "Enhancements" tab.

[gilly1984]

Re: My motherboard is too quiet.

Loudness off, the only other i have ticked is equalizer.

I know how to set the equalizer so thats ok, just not loud enough for me.

[ben7]

Re: My motherboard is too quiet.

How did you blow up the opamp? I think if you try it again - with our help - you could get it to work

[gilly1984]

Re: My motherboard is too quiet.

I had a little board with the opamp already on it, but i messed with caps then only 1 side would work

I have tried to follow guides on google for the Cmoy amp but its not clear enough for me to follow.

I struggle with the virtual gnd, If i could get guidance on all that stuff or a really easy diagram with real pics then i may be able to make one, i dont mind running it from a dc adapter either.

I dont need it deafening, just loud enough so i can feel the bass on my ears.

I have access to some smd opamps from broken ipod docks i have acquired.

[ben7]

Re: My motherboard is too quiet.

I had a little board with the opamp already on it, but i messed with caps then only 1 side would work

I have tried to follow guides on google for the Cmoy amp but its not clear enough for me to follow.

I struggle with the virtual gnd, If i could get guidance on all that stuff or a really easy diagram with real pics then i may be able to make one, i dont mind running it from a dc adapter either.

I dont need it deafening, just loud enough so i can feel the bass on my ears.

I have access to some smd opamps from broken ipod docks i have acquired.

I suggest that before you use any $3 "hi-fi" op-amps, try this with a simple cheapo dual op-amp. That way it is less expensive if you make a mistake!

The virtual ground is basically half the supply voltage. It is how you get the split-supply from a single rail supply (like a 9v battery).

If you use a 9v battery (for cmoy) you would have a 'positive' rail of 4.5v, and a 'negative' rail of -4.5v - each in respect the the ground (half the supply voltage)

V+   ---    ---
     |     |
    4.5v    |
     |     |
GND   ---    9v
     |     |
    4.5v    |
     |     |
V-   ---    ---

Say that for the above example, the power source was a 9v battery.
V+ is connected to the positive of the battery
V- is connected to the negative of the battery
Two resistors of the same value are connected in series from the V+ rail to V- rail.
The center point of the resistor voltage divider is half the supply voltage; this is what we call 'ground' in a split-supply. It is the common connection for both voltages.

This allows the opamp's output to swing from V+ to V-, creating an AC waveform.

This is just to help you learn this stuff. But in the real world, the resistor divider is very wasteful for high currents, and the voltage output (the dividend; 9/2 = 4.5) will change depending on the current flowing through each resistor. ( basic ohms law! )

Hope you can understand that xD

-Ben

[gilly1984]

Re: My motherboard is too quiet.

It may be basic ohms law but i still have no clue.

So, i can use any 2 of the same value resistor?

And when looking to make one it had caps on it too? With the resistors?

In parallel the caps were i believe? Or is this just the next step to provide constant power?

[ben7]

Re: My motherboard is too quiet.

It may be basic ohms law but i still have no clue.

So, i can use any 2 of the same value resistor?

And when looking to make one it had caps on it too? With the resistors?

In parallel the caps were i believe? Or is this just the next step to provide constant power?

The capacitors store energy, to give the opamp an extra burst of energy when needed without the voltage changing too much.

Assuming you will use a 12v supply, I think you could use two 470 ohm 1/2 watt resistors - you can get about 15mA from the split voltage. You can add a 220uF capacitor across each resistor.

I'm not so sure that you are even ready to do a project like this though

[gilly1984]

Re: My motherboard is too quiet.

Oh I'm ready, whether i will succeed we'll see.

What if i have a 12v ac tranny, does that make it easier or should i stick with dc.

Its quite simple the way you have put it so i think i am ready

[ben7]

Re: My motherboard is too quiet.

Oh I'm ready, whether i will succeed we'll see.

What if i have a 12v ac tranny, does that make it easier or should i stick with dc.

Its quite simple the way you have put it so i think i am ready

Well, ultimately it would be nice if it is regulated.

Does the transformer have a center tap?

[gilly1984]

Re: My motherboard is too quiet.

Its a transformer i took from a DAB radio.

It plugs straight into the ac outlet in my home and gives me 12v ac on the other side, so i am guessing its not regulated? But then, i have no idea.

[ben7]

Re: My motherboard is too quiet.

Its a transformer i took from a DAB radio.

It plugs straight into the ac outlet in my home and gives me 12v ac on the other side, so i am guessing its not regulated? But then, i have no idea.

How many wires are on the secondary?

[gilly1984]

Re: My motherboard is too quiet.

2 in 2 out.

[mariushm]

Re: My motherboard is too quiet.

If your transformer had a center tap (3 wires on the output ) then the center wire could be the "ground" and the wires on the sides could be +V and -V.

The transformer outputs AC current, so you need to rectify that to DC voltage.
That is usually done with a bridge rectifier, or with 4 diodes - basically it's the same thing. After the voltage is rectified, a capacitor is usually used to smooth out the DC voltage coming out of the bridge rectifier.


See http://en.wikipedia.org/wiki/Diode_bridge , especially the "Output smoothing" picture.

As your transformer is a plain simple transformer, you'll to use the two resistor trick after everything.

[gilly1984]

Re: My motherboard is too quiet.

I am going to use a wall adapter, its adjustable, from 3-12 volts.

I have managed to get my virtual ground going, didnt know it was so simple, and my head still doesnt know why it creates a virtual ground.

The opamp vcc will go to the + but where does the ground go? To the - or my virtual ground?

I looked at the scematic but it doesnt say.

[Uranium-235]

Re: My motherboard is too quiet.

your motherboard is supposed to be quiet. If it starts talking back, smack it

[gilly1984]

Re: My motherboard is too quiet.

Ha ha.

The volume is not super quiet, just not loud enough for me when i have had a drink.

I used to have 2 pairs of headphones (one for me one for pal) with the jacks cut off wired directly into the output of a technics mini seperates, they didnt last long but hell it sounded good.

[ben7]

Re: My motherboard is too quiet.

I am going to use a wall adapter, its adjustable, from 3-12 volts.

I have managed to get my virtual ground going, didnt know it was so simple, and my head still doesnt know why it creates a virtual ground.

The opamp vcc will go to the + but where does the ground go? To the - or my virtual ground?

I looked at the scematic but it doesnt say.

A quick tip: usually the op-amp power pins are called 'V+' and 'V-'.
Don't call the 'V-' 'ground', because that will confuse you. It is actually for the negative supply voltage.

[gilly1984]

Re: My motherboard is too quiet.

Yeah, i should google before asking, just read how to do it.

I know how to power it now, gonna carry on reading and sus out the input output connections.

[gilly1984]

Re: My motherboard is too quiet.

This tune is why i need it loud.

I know they didnt sing it bu i prefer to watch these singing it.

Even with the weird faces they pull they are sexy

http://www.youtube.com/watch?v=JaAWdljhD5o