Boombox project

[gandy]

My latest project, a boombox built with a Lepai LP-S60 4 x 25W Desktop Amplifier with Remote/USB/MP3/SD/FM. The amp is shown here on Amazon for $69.99 but I only paid $37 for it a few weeks ago.
http://amzn.com/dp/B0073GLC6U/?tag=bolehsedot-20
Here are front and back pics.


The speakers are Audiovox 5.25" coaxial 4 ohm. The only ones I had of this size that aren't blown.
The speaker cases are made from a paper tube that sheet flooring comes rolled on, very sturdy about 3/8" thick walls.
The "handle" is a battery hold down that I just bought today at Fleet Farm $5.75 w/tax. I needed something to hold the amp down tightly and this fit the bill for that and doubles as a handle.

I tell ya, this little amp really cranks! Much more volume than a standard boombox. It also picks up radio stations very well. It will play mp3s from a USB stick or SD/MMC card but it has no shuffle feature so it plays in alphabetical order. It has a 3.5mm input jack in front and RCA inputs in the back.

I considered adding two more 4" speakers using some smaller paper tubes I have but that may come later. The amp has clip terminals for four speakers.

 

[µT6]

impressive, looks like a commercial product!

how would you put the extra pair of speakers?  one each side?  slightly up, at the level of the amplifier?

[gandy]

I was thinking directly on top of the other speakers. They would fit because they are smaller. I have two 4" coaxials and them hooked up temporarily and the amp has enough power for them. I wanted to keep the weight down to a minimum so I didn't add them.

[ZX80Man]

Clever idea.
How are you powering it?  Does it use a lot of amps?

[gandy]

The amp comes with a 12v 3 amp AC adapter like a laptop uses. It can handle 12-14v 5 amps. I've seen people use a small 12v motorcycle battery with this type amp so I suppose it could be plugged into a car lighter socket with the right plug.

[joechimp]

Very Cool !

[µT6]

gandy, why did you choose lepai? price, size, audio quality or availability?

i have postponed a similar project for years but recently have considered to do what you did but with something like this

http://www.amazon.com/Dayton-Audio-B652-Bookshelf-Speaker/dp/B002RMPHMU/ref=pd_sim_e_4/175-7245244-8374918

[gandy]

I chose this amp for this project because it has an FM radio, the price was fair and it got mostly good reviews. It also comes with a good power supply, some don't or they have only a 2 amp wall wort.

I already have the Lepai 2020+ that I'm using for my desktop speakers. I'm impressed with that one.

Lepai also makes a few different models with FM http://www.amazon.com/Lepai-LP-269FS-Watts-Amplifier-Remote/dp/B0073WTG6M/ref=sr_1_2?s=electronics&ie=UTF8&qid=1363029769&sr=1-2&keywords=lepai+amplifier and this one http://www.amazon.com/Lepai-LP-A68-Digital-Amplifier-Remote/dp/B00721Z1AE/ref=pd_cp_e_1
but I read the reviews and didn't like what I read. The second one doesn't even have a display.

This amp could also be used as a car stereo since it's the same size and has a faceplate that would make for a clean looking installation. It also has terminals for four speakers.

I've read good reviews on those Dayton speakers but they seem a bit expensive right now. I've seen them as low as under $30.

[µT6]

i made a mistake with the link, i posted speakers but i wanted to post this

http://www.amazon.com/Pyle-PFA400U-Amplifier-Reader-Adapter/dp/B0071HZ5RI/ref=sr_1_22?s=electronics&ie=UTF8&qid=1363033147&sr=1-22&keywords=pyle+amplifier

i am going to do the same you did, use speakers i already have, mine are what survived from a sony stereo i had years ago



i also have a 2.1 speaker set, a old creative sbs 350 speakers, the amplifier refused to work again, after i checked and verified cables, soldiering points, capacitors and the amplifier itself, so i have lots of speakers around with enough power to make some noise 



it won't be as nice as your setup but maybe it will sound good too, what do you think?

[Yankee]

Looks very cool and space efficient, but there's nothing
better than 8 inch three ways, if you can fit them in.

Bigger tweeter and mid-range than normal computer
speakers as well.     IMHO

[µT6]

when you have space, yes, nothing better

those seems to be car speakers, should cover that as best as possible i think

[gandy]

One thing I hate is the power ratings claims of all these amps. They say 100 watts but what is that? Is it peak or RMS?

People who know more than I, have said that there's no way you can get these high wattages with only a 2 amp power supply. They say the math doesn't work out.

The amp I just bought claims to be 4 X 25 watts/channel. I'm guessing it's probably less than half of that in the real world. Still that's more power than an average boombox puts out. I've used up several in my years and when they go, I try to salvage the speakers. Most of the speakers have the power handling printed on the magnet and it's usually around 5 watts. So the amp probably isn't putting out that much.

If you don't need the FM radio, I would stick with the Lepai LP-2020a+. It puts out good sound at about half volume beyond that it starts to distort. It's only around $20 too so that's a good thing.

The fact that my new one plays from a USB stick or SD card isn't of much use to me since it has no shuffle feature. It also does not display song titles, just track number and time elapsed. The display is nice to have for FM stations. I plan to connect an MP3 player to one of the inputs and control the music from there.

I can't comment about your speakers. I just don't know if they will sound good or not.

Here's a video from a guy who put the 2020a+ through a oscilliscope, it may help you decide.

Lepai LP-2020A+ Tripath Class T Mini Amplifier - TA2020 - Amp Bench Test

Edit; Yes they are car speakers and bigger 3 ways would probably be better. As you probably know, car speakers vary widely in cost and quality. Space is an issue for me.

[Yankee]

One thing I hate is the power ratings claims of all these amps. They say 100 watts but what is that? Is it peak or RMS?

If you looked at a current Sherwood 100 watt 2 channel Receiver, the full specifications.
A few years ago those would be considered "audiophilic".     As well as old Scott
receivers and old Yamaha receivers.    Use those as your standard.     There are
others but imported and a thousand dollars more money.

How I'd hook up a Sherwood to a PC and run thru a music library I don't know.
I actually use 4 inch three-ways and an alsa-equalizer.    Fills up my whole
living room good, not superior, but also let's my neighbors sleep if I stay up late.

have a good one,

Y

[µT6]

if your setup sounds close or better to that(video one), it is a excellent project

i feel more encouraged to do it now, the problem is find a decent price, decent quality amplifier here, most of what i find, cost 80 dollars minimum and no idea what quality it will offer, that is why i ask so many questions, so i don't waste my money and end disappointed

[gandy]

I know what you mean. I spent many months off and on researching these little amps. It was hard to make a final decision.

I have to say, I think I made a good choice.

The  Lepai LP-S60 sounds as good or better than the Lepai LP-2020a+ and I think it has more power.

I wasn't aware that you live in Bogota. Can you buy from Amazon there?