I've seen lots of concerts outdoors with horn speakers. Efficient and the horn shape should drain light rain away. Too bad, they'd be too big for a portable boombox.
Every year I go camping and someone brings a little all-in-one box with 3" full range drivers. It seems to play forever on D cells.
Every year I go camping and someone brings a little all-in-one box with 3" full range drivers. It seems to play forever on D cells.
Yea a horn would be nice for the bass at least... very efficient. I've never seen one portable sized tho... 🙁Daveis said:
Well you can hook it up straight to your battery, but I butchered an old car amp as it makes 24v....Fast1one said:
I posted a pic or two in this thread:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=115515
The class D module I used is very similar to the AMP9 module.
Hi all,
I want to share the idea of my iPod boom box.
A pair of Philips TDA1515B have been used to drive max. 25W/CH to a pair of Pioneer 4" car audio 2-ways speakers. 24 pieces of 2500mAh NiMH rechargable batteries are used for its power supply. 12 pieces each to form 14.4VDC, 2 packs can provide 5Ah.
This machine can be switch as normal mode ( stereo ) or power save mode ( mono ). That means just one amplifier to drive 2 speakers in series. The size of the cabinet is around 4" x 4" x 12".
Suggestion : Bass reflection or passive speaker can be use if you want to increase the loudness of bass range.
More photos here :
http://www.fotop.net/VR2ZXP/VR2ZXP49
Cheers,
Fai.
I want to share the idea of my iPod boom box.
A pair of Philips TDA1515B have been used to drive max. 25W/CH to a pair of Pioneer 4" car audio 2-ways speakers. 24 pieces of 2500mAh NiMH rechargable batteries are used for its power supply. 12 pieces each to form 14.4VDC, 2 packs can provide 5Ah.
This machine can be switch as normal mode ( stereo ) or power save mode ( mono ). That means just one amplifier to drive 2 speakers in series. The size of the cabinet is around 4" x 4" x 12".
Suggestion : Bass reflection or passive speaker can be use if you want to increase the loudness of bass range.
More photos here :
http://www.fotop.net/VR2ZXP/VR2ZXP49
Cheers,
Fai.
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All connected and up and running... I've just got it hooked up to my phone at the minute, it's not the best quality source bit it's fine for testing. 🙂
I'm gonna run down the batteries and see if the amp6 switches itself off when the batteries go below 9v... we shall see.
It's at 12.4v right now, so I may be waiting quite a while, but I guess it's a good runtime test.
I'm gonna run down the batteries and see if the amp6 switches itself off when the batteries go below 9v... we shall see.
It's at 12.4v right now, so I may be waiting quite a while, but I guess it's a good runtime test.
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You can easily increase your voltage, by adding one more cell, to 13.8 volts, or somewhere thereabouts, can't you? 13.8 volts is the true voltage within an automobile, and 'so called' 12 volt units really operate best at that voltage. The alternator will be producing 14.5v across the battery terminals, but 13.8 is the real voltage to shoot for.
Someone please correct me if I am wrong here.
Someone please correct me if I am wrong here.
You are not wrong, but I have my reasons for going for 3 cells...John L said:
The datasheet says the absolute maximum is 16v, and there is also a diode which drops around half a volt.
So in theory I could just get away with it....
Bare in mind tho that Li-ion cells are 4.1v hot off the charger, so a 4 cell pack will be 16.4v which is a little too close for my liking... I like to have a little room for error. 🙂
Also, I'm using unprotected cells, and once they go below 2.5v, they die - they cannot be recharged. This is the main reason I've gone or a 3 cell pack. The amp6basic is ideal for 3 cells, as once it gets below 9v (or maybe 8v), it turns off, saving your cells from going below 3v.
If I was using PCB protected cells, I'd be tempted to go for a 4 cell setup, but I would still have a diode or a 7815 just to be sure the tripath doesn't get more than 16v. 🙂
BTW, music is still blaring away, I'm now on 11.5v... I think it's gonna be a while before this pack goes flat... Still I'm getting a good runtime. 🙂
Thanks! 🙂John L said:
The electrical stuff is pretty much finished, so now all I need to do is build an enclosure for the speakers and an Alu enclosure for the amp...
Over the past few days I've been trying to flatten the battery but been unsuccessful so far... It's at 11.3v right now, so still plenty of juice left. I've just been listening to the amp6 on some cheapy midi system speakers. They're 6 ohm and sound reasonable...
My Marshall stack alternative... "Bathroom stack": 😀 Having music in the shower is nice. 😎
My Marshall stack alternative... "Bathroom stack": 😀 Having music in the shower is nice. 😎
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