Re: Solar cell durability
That was my initial idea as well but when I tested it I had problems with the plexiglass eating away about 20% of the solar cells efficiency. And then there was the humidity problem if you let sit it outside overnight, as you would for a festival or similar, the plexiglass fogged over on the inside.
larzman said:
That was my initial idea as well but when I tested it I had problems with the plexiglass eating away about 20% of the solar cells efficiency. And then there was the humidity problem if you let sit it outside overnight, as you would for a festival or similar, the plexiglass fogged over on the inside.
Hmm, interesting dilemma with the condensation. Glad I mentioned it here, as I overlooked that particular issue. Thanks for the pointers, guess I'll have to figure out something else with the solar cells as they are an important piece of the ultimate boombox!
I'm trying to keep the cost down (wife acceptance factor), any ideas?
I'm trying to keep the cost down (wife acceptance factor), any ideas?
Well, tell her she can recharge her cellphone in the wilderness.
I just bought a Brunton Solaris 6, a high-efficiency solar panel that delivers 6.5 watts according to the specs. This one is actually flexible, and sort of rolls up like a wallet and is very portable, lightweight, weather-resistant. Rather than build it into my boombox, I just hooked up a power jack on the back of the boombox that parallels the battery. So, I can deploy the solar panel when the weather and usage calls for it, aim it in a different direction from the boombox itself, and it will reduce battery drain when playing or trickle charge if the unit is turned off. I disconnected the battery on a recent camping trip, and when the sun was out, it powered the Amp 32 up to about half volume, which wasn't bad for free energy.
It also comes with battery clips and a cord with a cigarette lighter socket so your wife can charge her cellphone, Ipod, whatever. Cost was about $130.
--Buckapound
I just bought a Brunton Solaris 6, a high-efficiency solar panel that delivers 6.5 watts according to the specs. This one is actually flexible, and sort of rolls up like a wallet and is very portable, lightweight, weather-resistant. Rather than build it into my boombox, I just hooked up a power jack on the back of the boombox that parallels the battery. So, I can deploy the solar panel when the weather and usage calls for it, aim it in a different direction from the boombox itself, and it will reduce battery drain when playing or trickle charge if the unit is turned off. I disconnected the battery on a recent camping trip, and when the sun was out, it powered the Amp 32 up to about half volume, which wasn't bad for free energy.
It also comes with battery clips and a cord with a cigarette lighter socket so your wife can charge her cellphone, Ipod, whatever. Cost was about $130.
--Buckapound
Yeah thats the same problem we are running into over and over. We are thinking about using a 24v truck-battery instead with a transformer, cause they rack up tons of aHs compared to the car ones. Maybe even boat batteries - for the same reason. Either way, the diesel ones seem to make more sense.
The only concern we have is that it needs to go for as long as it takes to recharge the other one. Preferrably around a day, so it's easy to maintain and get done during "quiet" hours. And not by just anyone either.
The batteries we are looking at are probably at least 88 aHs. That's the ones you'd find in e.g. a mercedes. With the testing you've done, how severe is the power loss with the auto head unit? I get some (rather depressing) results by calculating it, but what are your experiences? We simply HAVE to have CD support for all the idiots.
I'm not sure how it would work, but I've thought about using a CD drive from a computer. I've seen those with a full set of controls already in the hardware, so I guess it should work somehow.
Maybe even an old portable CD player stuck on top of the box. It would look terrible, but work.
Radio would be nice, but the thought of all the silly lights and functions I'd be powering bothers me quite alot.
And on an audio-board we end up discussing batteries... How un-amusing.
Pillah, the transformer, or DC-DC converter would suck out battery time as well. The point of using a class D amp is that you get 90%+ efficiency compared to the perhaps 30% maybe less that you would get in a regular cheapo headunit. If I were you I'd use a portable CD player capable of reading CDs with MP3. That's way you could play CDs, MP3 CD, or even connect an iPod when needed. And power it from the battery with a car power plug DC-DC converter which can also recharge your mobile phones, MP3 player etc.
That what I had in my first 2 versions, the current one is actually the 5th one I've built gradually improving over time as I came up with new ideas, learned more, and so on.
That what I had in my first 2 versions, the current one is actually the 5th one I've built gradually improving over time as I came up with new ideas, learned more, and so on.
you can pick up a sony discman on the net for peanuts. some of them'll run for 2 days on a single set of AA's. if your gonna get a diskman that plays mp3' get a reputable brand, the cheapos are a nightmare in every sense.
i rather devices that use aa or aaa batteries than the li-ion batteries that are found in a lot of devices nowadays. much easier to prepare for and work with in a field.
got a better shot of my one
http://i28.tinypic.com/oivn9z.jpg
i rather devices that use aa or aaa batteries than the li-ion batteries that are found in a lot of devices nowadays. much easier to prepare for and work with in a field.
got a better shot of my one
http://i28.tinypic.com/oivn9z.jpg
Saturnus said:
Of course, but I think it would still make sense if we use a 260 aH truck battery instead I'm thinking it'd still crank out some more even if we have to get it down to 12Vs... Also, it gets a lot more "unstealable" when the battery goes from 20 to 70 punds
btw, have you guys done anything especially fancy about the security? Thats still one of my number one concerns - to not get it stolen.
Pillah said:
You mean at Roskilde? Yes, naturally we just leave it at the Agora storage lockers whenever we go off to a concert or into town or something. It's actually much more secure to have a protable one you can just set in the store lockers than one several hundred pound one that can easily be stolen once you leave the camp. Though it's still very unlikely.
But frankly I don't get the point of the truck battery. It'll run maybe 750 hours at continues maximum volume but the festival is only 196 hours from opening to closing time. And since a standard sized car battery will make it run around 110 hours (at full maximum volume) it's a complete waste if you ask me.
Right, hijacking this thread as yet another Dane hopeful of making a Roskilde boombox. This project has a much lower budget, but could you guys check I'm not shooting myself in the foot here.
How much is 400W in terms of volume, by the way?
An externally hosted image should be here but it was not working when we last tested it.
How much is 400W in terms of volume, by the way?
Like NED 209 said, you have seriously misunderstood something, jchillerup, with those speakers you will never play loud even with 4000 watt amp. The speakers sensitivity is the most important parameter whether something will play loud or not, the amp is almost complete insignificant. And the amp you'd use would potentially drain the battery you have chosen in under 2 hours. Not that long a party.
Look for high sensitivity PA drivers. If you don't know what you're looking for then any bass guitar driver would be a good starting point. And ditch that amp and get a much smaller and much better class D one.
Look for high sensitivity PA drivers. If you don't know what you're looking for then any bass guitar driver would be a good starting point. And ditch that amp and get a much smaller and much better class D one.
the best starting point is to type sonic impact t-amp into google, and then start reading. and then keep reading. im not gonna pretend im technically competent, im not. most of the people on this forum are. audio is a science onto itself with an awful lot too it. if you like listening to music then its very interesting stuff.
be nice if there was a simple formula for beginners. like an amp32 or a t-amp, with some co-axial car speakers from pioneer, like the ts-a2010. theyre pretty efficient (93db), and they're no crossover needed. total simplicity.
http://cgi.ebay.de/PIONEER-TS-A2010...ryZ38768QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
its too simple though, theres gotta be a downside?
be nice if there was a simple formula for beginners. like an amp32 or a t-amp, with some co-axial car speakers from pioneer, like the ts-a2010. theyre pretty efficient (93db), and they're no crossover needed. total simplicity.
http://cgi.ebay.de/PIONEER-TS-A2010...ryZ38768QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
its too simple though, theres gotta be a downside?
I'd highly recommend the Amp 6 from 41 hz. very easy kit to do. Of course, the Amp 32 is more or less the same thing but with a much greater degree of difficulty with all that surface-mount soldering. Compared to a t-amp, even a well-modified one, there is much more bass response, and extra wattage to boot from the Amp 6. Decent battery life, too. Oh, and gain settings that work well with an iPod. I get somewhere between 6 and 12 hours of battery life at reasonable volumes from a 4.5 ah lead acid, more if I've got the solar panel plugged in.
--Buckapound
--Buckapound
Hey people.
Thanks for your replies. I have read about both the AMP6 from 41hz and the T-amp. While the T-amp looks really, really nice I couldn't find a place in Europe to buy it, and I wouldn't run the risk of having it caught in the customs.
The AMP6 indeed looks really nice, but I looked at some pictures of it, and I didn't see a volume knob. I know that it's a solder project and the knob might not have been connected at that time, but do you get one in the package?
I know that the speakers, not the amp, are the limiting factor, but I wanted to buy a set of better speakers once I could afford it, and I didn't want the amplifier to put limits on that. As for the power consumption I see that's a problem, but I suppose it wouldn't draw more than 500W (since the speakers suck 200W each), but then again I could be wrong.
I have some solid soldering experience (modding gaming consoles), so I reckon I'd be able to assemble the AMP6, but the info on their site is kind of sparse. Would it be possible to run it with that specific car battery, for example (something with the initial power burst)?
Last, what kind of speakers do you suggest? I'm not in the market for a very high-end solution, but not the very cheapest either. Again, THANK YOU for your replies. I'm sure it's going to be a kick-*** festival
Thanks for your replies. I have read about both the AMP6 from 41hz and the T-amp. While the T-amp looks really, really nice I couldn't find a place in Europe to buy it, and I wouldn't run the risk of having it caught in the customs.
The AMP6 indeed looks really nice, but I looked at some pictures of it, and I didn't see a volume knob. I know that it's a solder project and the knob might not have been connected at that time, but do you get one in the package?
I know that the speakers, not the amp, are the limiting factor, but I wanted to buy a set of better speakers once I could afford it, and I didn't want the amplifier to put limits on that. As for the power consumption I see that's a problem, but I suppose it wouldn't draw more than 500W (since the speakers suck 200W each), but then again I could be wrong.
I have some solid soldering experience (modding gaming consoles), so I reckon I'd be able to assemble the AMP6, but the info on their site is kind of sparse. Would it be possible to run it with that specific car battery, for example (something with the initial power burst)?
Last, what kind of speakers do you suggest? I'm not in the market for a very high-end solution, but not the very cheapest either. Again, THANK YOU for your replies. I'm sure it's going to be a kick-*** festival