12v Box,to horn or not?

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   Im starting a 12v rig in a big storage box, probably with 2xsubs, and 4x 6x9s

Couple of questions, 1) power, if your using a pc psu, do you match the wattage of qthe ampsq to the psu

2) is it better to make a horn, even a poor one inswtead of having tthe cones flapping out the sides?

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XYX Members Profile Send Private Message Find Members Posts Add to Buddy List New Member Joined: 30 December 2012 Status: Offline Points: 5	Post Options Post Reply Quote XYX Report Post Thanks(0) Quote Reply Topic: 12v Box,to horn or not? Posted: 13 January 2013 at 6:48am
	Im starting a 12v rig in a big storage box, probably with 2xsubs, and 4x 6x9s Couple of questions, 1) power, if your using a pc psu, do you match the wattage of qthe ampsq to the psu 2) is it better to make a horn, even a poor one inswtead of having tthe cones flapping out the sides?

Hemisphere Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 21 April 2008 Status: Offline Points: 2272	Post Options Post Reply Quote Hemisphere Report Post Thanks(0) Quote Reply Posted: 13 January 2013 at 8:06am
	Generally it's better not to use Car audio speakers for 12v unless you've literally got them knocking about with no other use and can't budget even 100 pounds or so for some more suitable drivers. heir frequency response and other characteristics are designed to operate inside a car which acts a bit like a giant speaker enclosure, so car audio bass will always be a bit thin outdoors - it relies on the cabin gain of the car to sound right. Depending on the quality and condition of what you've got it might even be worth chucking them on eBay and buying some PA drivers with the proceeds. In most cases it's not better to make a horn, although depending on how you intend to carry it around a tapped horn can provide good compact horn loaded bass. Not sure how you're hoping to use a computer PSU to power a system, unless you intend to use it mainly around the house. You need an amplifier capable of accepting a DC signal (12v, 24v or more, Class D amps as in the kits at 41hz.com or premade options from companies like "Sure Electronics" (not SHURE ;)) or a car amplifier, and connect those to a lead acid or lithium battery, or series of batteries. Edited by Hemisphere - 13 January 2013 at 8:07am

bitSmasher Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 23 June 2012 Location: Melbourne Status: Offline Points: 2296	Post Options Post Reply Quote bitSmasher Report Post Thanks(0) Quote Reply Posted: 13 January 2013 at 11:56pm
	Are you starting from scratch, buying the components? Or do you have them already? Also, Sure sell PSUs for their 12/24v amps. Worth looking in to buying a bundle.

XYX Members Profile Send Private Message Find Members Posts Add to Buddy List New Member Joined: 30 December 2012 Status: Offline Points: 5	Post Options Post Reply Quote XYX Report Post Thanks(0) Quote Reply Posted: 15 January 2013 at 9:29pm
	I do have the purchase the components, thats partly why i was going for car audio stuff: Head-unit (amp for speakers), speakers, amp for subs, subs, and a PC PSU since car audio runs off 12v, so you get to use a battery for outdoors, and switch to the PSU for indoor use I havent really got too much experience using proper PA gear, and i would have thought that would prove alot more expensive? I was thinking of the horn too for that punchy bass, my friends similar setup sounded nice and rumbly, but didnt have the punch, it also sounded pretty good outdoors considering all the speakers were mounted on the side, he had 1x8" sub, and 2 6x9s I am working on a bit of a tight budget, so bargain buys online would be ideal, again, car stuff comes up alot for this, i wouldnt really know what to choose for proper gear

bitSmasher Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 23 June 2012 Location: Melbourne Status: Offline Points: 2296	Post Options Post Reply Quote bitSmasher Report Post Thanks(0) Quote Reply Posted: 16 January 2013 at 12:34am
	To make car audio work "well" (or, "acceptable"), costs a lot more than entry-level PA stuff! What do you want to acheive with this? Might be worth wiping the drawing board clean and starting from the basics... budget, intentions, resources

infrasound Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 13 May 2011 Location: Brizzle Status: Offline Points: 2276	Post Options Post Reply Quote infrasound Report Post Thanks(0) Quote Reply Posted: 16 January 2013 at 1:00am
	Is this acceptable size wise? http://www.freespeakerplans.com/plans/14-plans/basscab/24-mth-30 If so, it will destroy any car audio outdoors! Otherwise, go for biggest PA cones possible in reflex for some proper punch. What's your budget?

XYX Members Profile Send Private Message Find Members Posts Add to Buddy List New Member Joined: 30 December 2012 Status: Offline Points: 5	Post Options Post Reply Quote XYX Report Post Thanks(0) Quote Reply Posted: 17 January 2013 at 11:09pm
	ok guys, the box dimensions are 106cm(L)x42cm(W)x56cm(H), the actual material is around 1.5/2cm thick and i did measure it on the outside i like the look of the reflex design, my old stereo had reflex drivers and sounded mental up load i take it you have to do some mathematical stuff to not make a hash job of it? what factors do you need to make note of when designing the position/size of the hole to the cone? @bitSmasher what would you need to do to make it work well? the plan is to use it indoors at low volume, but outside loud in a festival stall tent during the summer where it should hopefully sound quite nice

lost eden Members Profile Send Private Message Find Members Posts Add to Buddy List Young Croc Joined: 04 April 2011 Location: Dundee Status: Offline Points: 942	Post Options Post Reply Quote lost eden Report Post Thanks(0) Quote Reply Posted: 18 January 2013 at 11:56am
	Car head units/amps aren't ideal for running off battery because they aren't hugely efficient. Class D amps from Sure Electronics or 41Hz etc. are much better, but ideally you want to run most of them at 24v rather than 12v (more efficient, produce more power before developing too much THD). Computer PSUs aren't great for powering amps. 'Decent' computer PSUs are expensive (the £10 '500W' jobs you see on ebuyer will likely start a house fire when you try to actually pull anywhere near their rated power) & obviously they are only 12v not 24v. You'd be better off buying a 24v Meanwell which will be much better than an equivalently priced computer PSU http://www.ebay.co.uk/itm/Mean-Well-24V-DC-14-6A-350-4W-Regulated-Switching-Power-Supply-NES-350-24-/350593207969?pt=UK_BOI_Electrical_Test_Measurement_Equipment_ET&hash=item51a0fbcea1 Also if you're looking at the MTH-30 then you'll probably also want to look at the Cubo 12. Both are small 12" tapped horns. Edited by lost eden - 18 January 2013 at 11:57am

XYX Members Profile Send Private Message Find Members Posts Add to Buddy List New Member Joined: 30 December 2012 Status: Offline Points: 5	Post Options Post Reply Quote XYX Report Post Thanks(0) Quote Reply Posted: 19 January 2013 at 1:49pm
	i am aware of how gash the lowend PC PSUs are, i had a 500w one that couldnt manage my GPU AND a CD drive! that one looks like a good find though, and it being 350w will still power 2 amps if their wattage > than that? cant find a cubo12 only a cubo15 plan http://www.freespeakerplans.com/plans/14-plans/basscab/44-cubo15 and the back of the cone is meant to stick out the hole like that right? i think i could just about fit 2 of them in, maybe have to make them 8" instead, and these horn setups would be preferable to the suggested reflex setup?? (bearing in mind the reflex design is alot easier to achieve)

bitSmasher Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 23 June 2012 Location: Melbourne Status: Offline Points: 2296	Post Options Post Reply Quote bitSmasher Report Post Thanks(0) Quote Reply Posted: 21 January 2013 at 12:29am
	Cubo12 plans have disappeared from FSP.com, they are dead simple though so worth trying to build