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Amp for a homemade speaker box with car speakers? Answered

The speakers are almost definitely going to be a pair Sony Xplod XS-R5743's
190W Peak

So with these power specs, what should the power ratings for the amp be? I considered building an amp, and unless there is something I've missed, it looks cheaper just to buy a car amp and just make it run from a wall outlet after a transformer. Especially when every amp that I see being built is a low power 1W LM386.

Please, let me know the best method for amplifying the audio to these speakers and the required power.



For my car speaker boom boxes I use the Dayton T- amp from Parts express. It is small, can run off of batteries or a wall socket and at 15W per channel in a 4 ohm load is pretty loud especially with efficient car speakers. http://www.parts-express.com/pe/showdetl.cfm?Partnumber=300-380 or if you just want the amp unit http://www.parts-express.com/pe/showdetl.cfm?Partnumber=300-385 if you just get the PCB I would recommend getting the 12V power adapter they offer A cheap car receiver head or a small car amp would work well too. For wattage the number to look at is the RMS not the Peak. Good Luck.

Building a nice amp will cost a little more than buying one. I built a LM3886 amp (68W) from Chipamp.com and it ran me a little less than a $100 because I already had a transformer. If you want to build the amp from a kit check out 41hz.com. They have a bunch of T-amps that get good reviews. I would recommend the BASIC series unless you want to wind your own toroids and solder SMD's.

These amps from parts-express look pretty useful. They fit right onto the back of the enclosure. http://www.parts-express.com/wizards/searchResults.cfm?srchExt=CAT&srchCat=966

Yes, you want a power amp if you want a significant amount of volume without distortion. A standard home-stereo amp will work just fine; there are lots of those available as people upgrade. Make sure the amp will tolerate 4-ohm speakers; most prefer 8-ohm but will tolerate 4-ohm (though not lower).