12v Eco project sound system

D

Daniel Cumberland

Freshman
Feb 27, 2011
30
0
0
hi there

i am wanting to build a super Efficient sound system for our eco project 'Treadle'.

the idea is to generate pro quality audio converting our 12v dc power most efficiently and effectively into sound [DB].

from what i understand it is possible to achieve a pretty decent sound level [100 db?]and quality. for a capacity of around 100-200 people.

my findings thus far [and bare in mind please i am still very much a newbie to these sound matters]

- active crossover [separating high and low frequencies pre-amplification]
- 4 x mono block Class D/T amps @around 20watts/channel [subs R/L - Tops R/L]
- 2 x highly efficient tops + 2 x hightly efficient Subs
[previously i was posting on the billfitzmaurice site and looking at the DR250's and Titan 39's]

we will play electronica and Bass sounds, as well as live instrumentation from time to time.

now b4 i went ahead and purchased the designs for the cabs i wanted to ask some knowaglbe folk about their opinion on both bills speakers and my set up ideas?

COMPROMISE & CONTEMPLATIONS

- BUILD - more sophisticated - over simplicity [active crossover-time-complexity]
- SIZE - Efficiency - rather than smallness
- SOUND - Subs & Tops - Over all in One
- COST - more efficient cabs [bigger builds] do not seem to be considerably more expensive.

we dont have tons of cash, we like to give new life to dis-guarded objects
generate our own power and recycle.
but we do have time [not a wkend build] and construction skills.

any import would be very much appreciated

thx

wellington
 
Re: 12v Eco project sound system

right then i would like to reintroduce myself as dan

middle name wellington

knowledgeable folk kind sir, excuse the local lingo

no how about my rig?
can any one give me any feed back?

cheers

dwc
 
Re: 12v Eco project sound system

Dan:
You haven't got a fixed time-line on this?
( The intent is to add plans here for LF and HF cabs - in the future. )
I remember your initial post on the BF; of course there for obvious reasons the conversations HAD to be limited to BF designs.
Have you looked at other speaker plans?
I do recall suggesting that these small 12V Class D/T amps would not be my choice.
 
Re: 12v Eco project sound system

Dan,

The voltage is not so significant as the amperage you have available. What is your actual power system? Wet cell batteries? How much current can it supply, long term and short term? You can make a lot of noise with very little power mostly by using high efficiency loudspeakers. Most modern amplifiers are very efficient.
 
Re: 12v Eco project sound system

hey up rob

well the structure nearly done
so looking to get with with the speakers now

i do recall your comment on amps.
i do not know which a/b amps to look at or how could be comparable on efficiency
etc? and would they not be alot more dosh?
i recall being interested in the idea of and a/b for the highs [if would run efficiently on my 12volts]
working with d/t for subs and getting the best of both.

no have not looked at other speaker plans...
i was hoping you lot maybe able to steer me in the direction of some alternatives
and/or help me to be sure that BF designs would be a good choice.

dwc
 
Re: 12v Eco project sound system

Bennett

we got 2x 100 amp hr AGM deep cycle battery's
run though charge controller with with a ultra capacitor dump load
giving instantaneous current bursts when needed.

charged by our treadle machine [like peddle powered generator]


 
Re: 12v Eco project sound system

I would suggest trying a Waves Maxxbass processor. These can leave bass perception intact but SIGNIFICANTLY reduce the actual load placed on the subwoofer. Given that lower frequencies require the most amplification and the nature of the music you are playing, this seems like a great fit for this project to ensure that you can keep power draw minimal. Please note, ONLY the Maxxbass, not other "Bass Enhancers" or Subharmonic synths. Those are not the same thing at all.
 
Re: 12v Eco project sound system

Daniel Cumberland said:
- 2 x highly efficient tops + 2 x hightly efficient Subs
[previously i was posting on the billfitzmaurice site and looking at the DR250's and Titan 39's]

now b4 i went ahead and purchased the designs for the cabs i wanted to ask some knowaglbe folk about their opinion on both bills speakers and my set up ideas?
Click to expand...

I would suggest that by the time you eq the BFM boxes to a relatively linear response, you will have lost a good part of their claimed sensitivity advantages. Also IMHO the "piezo array" only sounds about as good as an ENTRY LEVEL compression driver, has a very high crossover point, has considerable potential for inconsistencies between piezos, has limited peak headroom, has jagged response particularly off axis, etc, etc. I'm also not a fan of the lengthy "U turn" curved MF horn extending to such high frequencies, as there is higher potential for interference as the freq rises.

They might be fine for your needs, certainly you can build them very cheaply. But I do find that the performance claims sometimes are overstated, so want to ensure you have fairly realistic expectations of capabilities. Fitz frustrates me sometimes with comparisons, for example his comparing the DR300 to an EAW KF760, which is just completely ridiculous.
 
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Re: 12v Eco project sound system

all interesting stuff Jeff!

i like the missing harmonic link story! with maxxbass. though i never been so int rested in car audio as its made to run of an alternator not offgrid. and our speakers will never be put under strain from what i understand as they will be able to be pushed alot more than are 12v amp capabilitys.

Great also to hear some unflattering view of BF designs to balance things out. i knew it couldn't be all good with them.
i guess it is going to come down to the best we can get for our buck. could you suggest any alternative designs?
we dont have many more bucks than this system would take to construct :(
 
Re: 12v Eco project sound system

Daniel Cumberland said:
hey up rob
...well the structure nearly done...
i recall being interested in the idea of and a/b for the highs [if would run efficiently on my 12volts]...
no have not looked at other speaker plans...
i was hoping you lot maybe able to steer me in the direction of some alternatives
and/or help me to be sure that BF designs would be a good choice...
Click to expand...
I thought the "structure" was fairly small - that lowers the power demand.
There were variables and considerations in your scenario ( as I recall ).
I suggested using car stereo amps for various reasons: there is a large existing pool of amps to draw/recycle from.
Car amplifiers first setup up voltage internally - this increased voltage means decreased current flow and the internal components/wires and circuits paths can handle more power.
Not to launch a huge debate on Class D, but IMVHO the efficiency/weight strengths of the design is vastly over-hyped, and real good quality class D amps don't come cheap.
And the disadvantages weight/inefficiency and heat of the others classes is over emphasized. Amplifiers don't have a duty cycle like a resistance heater and their energy consumption pales against something like a plasma screen or stage lights.
Assuming this is a permanent install(?) then weight and size of speaker cabs is not an issue?
( I couldn't give an honest objective opinion on appropriateness of BF designs in your scenario ).
we will play electronica and Bass sounds, as well as live instrumentation from time to time.
Click to expand...
Since I don't know what that genre demands in terms of LF that's an important variable.
 
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Re: 12v Eco project sound system

well our structure is 6meters in height and 15-20meter closed or open in diameter
and it is a traveling project and will move around alot. cab sizes and weight is not a big issue and we have agreed bigger to maximize efficiency and sound.

i suspect there is alot of hype around class d/t amps but do seem widely used in the free-party festival scenes playing electronic music.

again im not set on one but just what is going to best suit are scenario.
and i would think were are talking some pretty low bass extension is gonna be needed, particularly because i personally like the soothing atmospheric, calming and gentle effect of deep bass resonances in ambient and psycadelic electronica. hmmm i wld like to get that consuming feeling from our subs not loudness essentially but feeling the sound
 
Re: 12v Eco project sound system

Dan:
I built only 2 BF designs and while I've read everything BF has written about his designs since way before he started selling plans, I haven't heard the designs you mentioned. That's why I value the object feedback I've gotten from guys ( like Jeff and Ron ) on their experience with BF designs.
One of the most powerful biases that confront a DIYer is expectation bias or what I call builder's bias: Basically the builder is convinced the end result sounds good because it has to - the builder simply puts so much time/energy to admit defeat, or caves into opinion of others.
A forum ( ancillary to a business ) probably cannot expected to be completely objective, if BF can make money to some selling plans ( some of which haven't changed in 50 years ) that's fine.
In the past decade with the advent of computer based modeling and testing there are a lot of options.
A major reason that sound systems demands are identified and quantified is to logically determine what is needed/will work. That does require valid predicable performance from a speaker design.
 
Re: 12v Eco project sound system

Daniel Cumberland said:
well our structure is 6meters in height and 15-20meter closed or open in diameter
and it is a traveling project and will move around alot. cab sizes and weight is not a big issue and we have agreed bigger to maximize efficiency and sound.

i suspect there is alot of hype around class d/t amps but do seem widely used in the free-party festival scenes playing electronic music.

again im not set on one but just what is going to best suit are scenario.
and i would think were are talking some pretty low bass extension is gonna be needed, particularly because i personally like the soothing atmospheric, calming and gentle effect of deep bass resonances in ambient and psycadelic electronica. hmmm i wld like to get that consuming feeling from our subs not loudness essentially but feeling the sound
Click to expand...


Well, there's green and there's green. How green is it moving around large physical apparati even if it is nominally efficient at what it does???? You lose in logisitics what you gain in performance. Everything is everything, as the saying goes.

Now if you want to give everyone the same sonic experience with a minimum "carbon footprint", consider individual receivers/transducers all tuned in to a low-power FM broadcaster. This is as efficient as you can get because 100% of the sonic energy is delivered to the user/listeners with none of the energy lost to the air. Use rechargeable batteries and charge up from solar/treadle/whatever. You could call it a WePod............
 
Re: 12v Eco project sound system

no ive not heard either rob. and want speakers to sound good, aside from having built them or not.
the intoxicating nature of sound to penetrate the body and generate emotive response is highly significant and important here.
... so were you pleased with your bf designs.

and could u suggest a highly sensitive alternative to bill stuff i might build?
i wld like something that has used modern day technology to identify a good build too

ohh and class a/? amp ?
 
Re: 12v Eco project sound system

So this structure and the system is to be moved frequently?
( Bottom line was the BF designs did not surpass what I already had )
 
Re: 12v Eco project sound system

Daniel Cumberland said:
no ive not heard either rob. and want speakers to sound good, aside from having built them or not.
the intoxicating nature of sound to penetrate the body and generate emotive response is highly significant and important here.
... so were you pleased with your bf designs.

and could u suggest a highly sensitive alternative to bill stuff i might build?
i wld like something that has used modern day technology to identify a good build too
Click to expand...

Where are you located?
 
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