ghetto blaster

[lejaybo]

howdy peoples

i wanna make a simple ghetto blaster style portable system

doesn't have to sound the greatest but i'm looking for a simple amplifer that'll run of batteries

plus has anyone played with dab tuners?][;p

 

[teherrorofdoom]

im currentley working on a 2x 20 watt amp using the tda 2003 its quite cheap to make and decent sound quality i dont know what its like with regular batterys but it runs for a good time on my drill battery

anyway heres the circuit diagram for it

 

[star882]

There are plenty of hybrid digital chips designed for battery operation. Of course, pretty much all of them are SMD. But some of them are still easy to work with.

 

[lejaybo]

sweet i'll have a butchers

i found some old low power 8inch cheap drivers

i wonder if thats a bit too much for a ghetto blaster lol

 

[Stuey]

Too much? Check this...!

http://www.diyaudio.com/forums/showthread.php?s=&threadid=104402&highlight=

 

[benchtester]

howdy peoples

i wanna make a simple ghetto blaster style portable system

doesn't have to sound the greatest but i'm looking for a simple amplifer that'll run of batteries

plus has anyone played with dab tuners?][;p

Parts Express has a sale on a T-amp (today only?). Sounds pretty decent and is pretty efficient.

 

[AndrewT]

for battery operation use high efficiency speakers.
8ohm >=96dB/W/m or 4ohm >=96dB/W/m>=99dB/2.83V/m

 

[Rainwulf]

TEA2025 is a nice simple chip that will run BTL, runs of 6-12 volts, and will put 4.7 watts into an 8ohm speaker in BTL.
Idea chip for battery operated devices.

 

[johnr66]

What battery type do you plan to use? What voltage?

I just got some TDA7267 ICs. After doing careful tests with my oscilloscope and function generator, I found it to deliver 1.8 watts (non clipping) into a 5 Ohm load with a 9 volt Vs. This is very good performance for a single ended output IC. It requires very few components.

 

[lejaybo]

cool info guys

i'm thinking roughly to use 9 to 12 volts
AA tyes me thinks, something thats easily avaiable

the best power i can get for this power is my aim

plus i know it'll sound a bit better than those plastic crapola boombox i keep seeing


anyone seen quad channel IC ?

 

[pjp]

With AA cells you'll never get enough volume for outdoor use.
You want something that can deliver greater current.

If you are up to the complexity of the charger design, I suggest using Lithium Ion cells. (The type used to re-cell laptop batteries.)
Or the Li Polymer cells used by model aircraft builders. (Costs more.)

Additionally, if you care about battery life, a class D design will make a very big difference.

 

[Rainwulf]

A really good chip quad IC for battery power (12 volts ideally) is the TDA7375.
4 seperate channels, and each channel can be bridged for 2 channels with a lot more power.
You can create your 12 volts with a gell cell.


can put 35 watts into two speakers.

Have a read of this.
http://pdf1.alldatasheet.com/datasheet-pdf/view/25150/STMICROELECTRONICS/TDA7375.html

 

[johnr66]

With AA batteries, even the the single ended amps will run them down quite a bit after just an hour or two of listening with 4 ohm loads at high volumes.

While bridge amps can make 4x the power of single ended, they will run even D cells down quickly.

I recommend a single ended amp with efficient speakers. I used guitar speaker once and the setup was screaming loud, even at 1 watt. Sound may not be hifi, but it was better than most off the shelf boom boxes.

 

[lejaybo]

cool

i saw some li polymers. my matres got some for his plane

never thought to used batteries like that

might use two in parallel for some tasty current


i'm thinking of using a coxial and a std driver hence the 4 channels

more investigation required!!!

 

[star882]

Look for some older but usable laptop batteries. If you can figure out the pinout, the voltage is just right for some TI hybrid chipsets.

 

[lejaybo]

cool i got a few old laptops knocking about

to the bat cave!!!!!!!!!