simple PC mini-amp project ?

[jives11]

Hi,


I have a PC with a sound card and some cheap active speakers. I also have some better passive speakers (RadioShack Genexa s with Lineaum tweeters). The speakers provide some music and some effects for games. Not too critical. It would be good if I could use the passive speakers with the PC , So ....



I could get a commercial power amp, but really want something smaller which will fit on my desk without taking up too much space. It would also be good if the amp could be run from a 12v dc supply as I have a PCI card which provides external supplies off of the PC PSU.

I'm kind of surprised that a commercial 12v mini amp doesn't exist as it could be used with mp3/cd/iPod type applications and anywhere there existed a 12v supply (i.e a boat, caravan etc)


I was thinking about a couple of mono chipamps with a 10Klog put to provide some volume control.


anyone had any experience in this area or can recomend a design ?


So ......


anyone built a chipamp for this kind of application ?

 

[aditaquil]

Hi,
Need to know power of your PC PSU and 12V DC current on PCI card.

 

[purplepeople]

I'm kind of surprised that a commercial 12v mini amp doesn't exist as it could be used with mp3/cd/iPod type applications and anywhere there existed a 12v supply (i.e a boat, caravan etc)

Actually, they're called car stereos. Your chip amp idea is good. Both the LM4750 and the TPA1517 can use 12v single supply and provide around 5W with 1% THD+N. The TI chip seems to have a better SNR and less distortion and noise at any given output.

ensen.

 

[Bill Fitzpatrick]

There are tens of millions of mini-amps that run from 12vdc. Simply visit your car stereo dealer.

Rats, someone beat me to it.

 

[sayang001]

If you want to build something yourself have a look at the TDA2003 10W amplifier.

http://www.electronic-kits-and-projects.com/kit-files/datasheets/tda2003.pdf

 

[UrSv]

Depending on what you mean with mini-amp then several thousands probably exist as pointed out by others. The one below has created a religious following and is used by many to power their main systems.

It's small, runs off 12 V and apparently sounds great:

http://www.sjgreatdeals.com/sit5066.html

 

[DT]

Some years ago i have build for my computer sound system a 12V amplifier on TDA2005 with regulator, standart schematic. And till now this tiny amp sounds for me very nice
Schematic can be found on datasheet or on my site:

TDA2005 amp

and some photos ...

 

[mcs]

I made a small amp using the TDA1510 some years ago - but I think that chip is obsolete now...

Best regards,

Mikkel C. Simonsen

 

[purplepeople]

Bill: I'm not trying to prevent you having any fun... honest!

UrSv: That's the digital amp that everyone's been talking about modding in another thread.

DT: That is one big faceplate!

ensen

 

[jives11]

Thanks to one and all

Many thanks for the responses.


Car stereos - of course. yes - an inspired suggestion

The PCI power card is really a module which slots in a PCI slot and exposes 3,5 or 12Volt supplies as tapped off spare ATX PSU taps. I thinkmost PC's can deliver high current , possibly as high as 5 amps. However these are switched mode supplies so probably quite noisey.


however the Sonic Impact 5066 digital amp looks to be "exactly" what I had in mind. Now just got to figure out how to get one to Europe. Odd that they are US only as they have no regional PSU changes to make. Many thanks

 

[mac]

Looks like you already found the $30 SI amp. Appears to be a good choice.

 

[Sherman]

Looks like you already found the $30 SI amp. Appears to be a good choice.

Yesterday I just finished "modding" a Sonic Impact. Actually it was really more of a "re-casing" than modifying. I put it in a small aluminum case from Fry's, added a better volume pot, put two inputs on the back selected by a DPDT switch on the front and added a separate power switch on front.

It looks very nice and sounds better than the stock SI. I think that may be due to the higher quality volume pot and input jacks since I really made no changes to the circuit. I'm using it as the amp in my office but it would make a great amp for a PC (and you wouldn't have to change anything)!