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solar power amp/cabinet combo... feasible?

Mar 1, 2008
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I'm attempting an interesting project, but wanted to gather initial assistance and advice from the Talkbass community before even trying.

Essentially, I would like to build an amp or amp/cabinet capable of producing adequate acoustic/coffeehouse levels of volume but powered entirely with renewable energy. No, this isn't meant to replace conventional needs, but rather act as a standalone exhibit that is also practical.

Here's my ideas and musings thus far:

It would be difficult to provide the voltage/amps required of most existing systems from a small photovoltaic system wind, except maybe pedal powered generators. Therefore, a new amplifier would be needed...

TO keep things cheaper and simple, the power source would most likely be coming from solar, and therefore a DC current. Storage would be ideal (to play in low-light and indoor conditions). This could utilize a battery, or even a car battery, etc.

As far as the speaker and amplifier, I do not have much electronic engineering expertise. I was thinking that car audio would be the place to source these items, being that they are already meant to run on a DC circuit. Perhaps an amplifier for a subwoofer and a car audio subwoofer/box. Plus, with the rate that my generation likes to 'pimp' their rides with these obnoxious systems, I'm sure there are plenty of cheap, used parts out there.

That's a just a little bit of what I've been thinking. I could also use help designing the cabinet box itself, but that will be later in development.

So fellow Talkbass community members: Is that at all possible? And would anyone have any ideas/advice?
 
Check the Wattage output from a solar array.

If you hat is big enough to mount enough cells --- then maybe.

What bout at night or during an eclipse?

How about during a three-alarm Zombie attack - since I hear zombies only come out at night you may be safe though.

Can't play a bass and run too. At night. One or the other.
 
Plenty of companies already make small combos for busking, street venues, coffee houses etc. These are typically battery powered. If your house has panels, wait for a day when you've got a surplus or are feeding back onto the grid and charge it up.

If you're starting from scratch, you'll basically want a battery, preamp, amp and speaker. Aim for a high sensitivity speaker/cab so you don't have to use as much power. Take a high-efficiency amp (servo maybe?) and cut out its AC transformer. It will probably be a 12~24v system. Then just attach it to some batteries in series.

I can't think of any renewable energy system that can provide the on-demand power required during amplifier usage (other than geo-thermal, and who wants to tote a whole planet to a gig). You'd need some batteries or caps or something to discharge and provide headroom during peaks. Charging those via green energy would be halfway there though.

If you're designing a marketable system, be green throughout the whole product lifecycle. Don't design for cheap mass production and assemble-once philosophy. Design for ease of servicing, breakdown and eventual recycling. Don't design a product, design a life cycle...
 
Double Bass, i.e. Upright Bass, Acoustic Bass, amplify the sound of the strings acoustically. They are often built from renewable resources like plywood. Built one with Frets :hiding:

If you want a cab.
A high efficiency design like a Bill Fitzmaurice design will only need a fraction of the wattage of another amp.
Class-D - if designed for low wattage, also uses a fraction of the energy another amp class would.
Human hearing is inefficient at bass frequencies - and it typically needs more power to reproduce to the same level as say a guitar in the mid-ranges would.
 
Hi.

Feasible? No.

Doable? Perfectly.

Cool? Kind of.

Haulable? Not really.

IIRC the power/price ratio is roughly 0.1W/€ for a system that's something more than just a toy.

A cool idea, that's for sure, but not practical by any means. Speaking only as an engineer of course.

Regards
Sam
 
By way of comparison, those outdoor walkway-illuminating solar-powered LED lamps get charged all day by the sun, and then at night they are only able to power a single white LED for about three hours. You could reasonable extrapolate that to three LEDs for one hour, which is about the length of a coffeehouse gig. So if a 3"x3" solar panel and battery with a day's charge can only power three LED's for the duration of the gig, what size of panel would you need to power an amplifier?

The PJ one looks cool, but I am extremely skeptical that it could run for longer than a few minutes.
 
From another view point:
You will waste more energy and polute the planet more by building such a rig than you could ever possibly hope to save from using one.
.02
 
Great comments all around, and thanks for the tidbits.

A few responses:

Cradle to cradle and design lifecycles for sustainability are one of my favorite topics. That being said, I was mainly aiming at a one time use, exhibition piece for my college's student environmental sustainability organization and other things. But its great to see others with that mindset.

As far as the use of it versus construction- I would probably acquire everything used/previously owned as to avoid having to purchase any new materials (besides wire, solder, and other absolute essentials).

Does anyone know how the PJ one works? My guess is it charges an internal battery (probably over a very long time frame) and then discharges it quickly.

And I would really be looking to be able to charge it (or place it outdoors) and utilize it after a <thorough> charge.


Please keep the ideas/suggestions coming. I'm in the preliminary stages (and have very little elec. engineering/'inventing' experience), and won't have time to start this project until December. But any help, comments, and criticisms are definitely appreciated.
 
Now, some battery powered amps already exist... Not super loud- or even close to loud- but that plus a solar powered- AA charger and it'd be a very easy (albeit not exactly sustainably designed) solution...

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I've looked into the Phil Jones thing. It is essentially an internal battery that can charge via AC or the panels for 10 hours per every one hour playing time... They go (or were going) for $995.

I wonder if something like the Markbass Micro 1x6 could somehow be modified to run off of a DC battery current.. probably not. I still think it would take a 12-24V system as someone suggested, perhaps car audio, built by hand. Especially to achieve anything with some what decent volume.
 
If I had to build something like this with the above enviornmental goals and with limited cash I would:

* Research solar cells to see what's available either used or in your bugdet range new
* Buy a used Rolland bass amps that have 4 small speakers that run off batteries; under $200 new, maybe $125 used; not real loud but battery life is reported to be good; I would assume this means the amp/speaker combo are effecient
* Consider using an inexpensive motorcycle battery (about $30), use resistors to lower the voltage if neccessary, and look for used solar cells on eBay

If money is no object, buy the best solar cells you can find and ask an EE at school to help spec the project
 
Step 1: Invent small solar panel that can make juice in dark clubs using neon and colored stage lighting.

Step 2: Refine it so it's efficient enough to power amplifier.:D


All kidding aside, looking into current battery powered offerings and charging them with solar may be your next best bet. Solar's getting better all the time but I don't think we're there yet although there are some small "camping size" solar units that can supply rechargable batteries, cellphones, small radios, etc. Maybe start there?
 
Someone said this was 'kind of' cool. This is the 2nd coolest thing I have read on TalkBass, behind GE giving that dude a bass and reuniting him with his family. I know it may not be altogether possible but the thought is far better than most every thread on here.
 
The PJ one looks cool, but I am extremely skeptical that it could run for longer than a few minutes.

For the record, I believe Phil built that more or less for kicks (and to prove that it could be done). He has no plans that I know of to mass produce these.
 
I'm attempting an interesting project, but wanted to gather initial assistance and advice from the Talkbass community before even trying. ... The power source would most likely be coming from solar ... So fellow Talkbass community members: Is that at all possible? And would anyone have any ideas/advice?

Well, start with the fact that the available power from the sun is roughly 1000 watts per square meter at sea level on a clear day when the sun is directly overhead (and remember, that's noon when the sun is directly above your particular latitude--excepting Hawaii, this never happens in the United States because it's too far north). Available power drops off when it's not directly overhead, when it's cloudy, etc. Then, consider the fact that solar arrays aren't very efficient (less than 20% for the best ones if I understand correctly). A little math suggests that you would probably be best served spending your time on something else.