Active Speaker for the PC

[loukas21]

Hello guys!
I'm new and im working on "Active Speaker for the PC" project.
I find a guide on internet and wanted to create it.

And this is the results:


But its play like i have a headphones and its hard to hear.
I use:
1x12V adapter
1xAN7312 IC
2x10Kohm resistors
2x1000ohm resistors
2x8Ω 3W speakers
Any suggestion..?
Sorry for bad english

 

[JimB]

Any suggestion..?

The AN7312 is intended to be a pre-amplifier, not a power amplifier which can drive a speaker.

Your circuit is completely wrong, even with the AN7312 being totally inappropriate, the circuit is just plain wrong.

There must be many suitable circuits on the net, where did you find the "guide" which pointed you to that circuit?

JimB

 

[loukas21]

https://www.ehow.com/how_6537997_build-own-active-speaker-pc.html
Here..

 

[loukas21]

Type on Google:
"How to Build Your Own Active Speaker for the PC "
The first site from ehow

 

[alec_t]

its play like i have a headphones and its hard to hear.

I'm not surprised. That IC is a pre-amplifier, not a power amplifier, so it can't drive 8Ω speakers properly. Also, the supply and channel wiring in the schematic is incorrect. Use the pins as per the datasheet.

 

[loukas21]

so i need to buy a new IC.
and when its say "non-inverting input A" on 556 IC its not output A ?

 

[alec_t]

when its say "non-inverting input A" on 556 IC its not output A ?

1) A 'non-inverting input' is an input.
2) A '556 IC' normally refers to a dual timer IC. Are you confusing that with a AN7312?

 

[loukas21]

maybe i confusing it ..
so with AN7312 i cant do that i want right?

 

[MrAl]

Hi,

Also i notice that in your schematic you are using a two conductor phone plug to plug into the computer. Most computer outputs are stereo and that would mean you need a three conductor phone plug not a two conductor. If your sound card really does have a two conductor output then you are ok, but most have three conductor phone jacks so i thought i would mention this.

The two conductor phone plug has one ground, one signal wire. The three conductor has one ground, but two signal wires one for each channel (stereo).

BTW how much output power do you want to have for this thing? 1 watt is enough for speakers unless you are looking for a very loud system.
Also, what kind of power source do you have available to run the chip?

An example of a audio power amp chip is the TDA1554 ic chip. I've never used it though but it doesnt look too bad. Takes 14v power supply input or so.

 

[JimB]

https://www.ehow.com/how_6537997_build-own-active-speaker-pc.html
Here..

A dreadfull article!
Not worth the electrons used to transmit it!

JimB

 

[loukas21]

i have to types of speakers, 0,5W and 3W
i think i can make and with 0.5W but i cant find a schematic plus i need to find and new IC..

 

[alec_t]

Have you considered the LM386N IC? It can drive an 8Ω speaker at up to ~500mW. You would need two for stereo. The datasheet includes schematics.

 

[Mr RB]

Yep, lots of cheap little PC powered speaker sets have LM386 ICs in them.

But of course you can buy those little powered speakers for a few bucks on ebay, so why build?

 

[loukas21]

exercise my friend
ok i will go to find lm386
where i can find a good schematics?

 

[BeerBelly]

exercise my friend
ok i will go to find lm386
where i can find a good schematics?

https://www.mouser.com/ds/2/282/snas545a-56527.pdf

 

[loukas21]

Thanks BeerBelly!
With this IC and this Schematic it will work right?

 

[BeerBelly]

Yes, It is a very common part for this purpose.

 

[Mr RB]

And the LM386 datasheet has examples of minimum-parts audo amps. Download a few different manufacturer's LM386 datasheets, some have more example circuits than others.

 

[loukas21]

ok! im on my way!