Boombox "ghetto blaster"-design

[axebay]

Smallest LiFeYPO4 battery i found was at 3,4 kg, a bit to heavy:/

http://www.monacor.dk/produkter/hoej...nt/vnr/110480/ perhaps these will be a better chioce, think I saw them as one of the recomended in the boominatortread at diyaudio?

[Giro 416]

http://www.europe-audio.com/Product.asp?Product_ID=5608 this one is good imo

[axebay]

The specs seem to fit good. But since I'm mostly gonna use it outdoors shouldn't I have it in some sort of horn to get an acceptabel dispersion?

[Saturnus]

The specs seem to fit good. But since I'm mostly gonna use it outdoors shouldn't I have it in some sort of horn to get an acceptabel dispersion?

Horns limit dispersion. That's the principle on how they work.

If I were to recommend a match for those midwoofers it would be:

http://www.europe-audio.com/Product.asp?Product_ID=2696

with the waveguide

http://www.europe-audio.com/Product.asp?Product_ID=5216

This has really good sound quality (it's used in some ultra-hi-end speakers) and very high sensitivity, and directed dispersion.

I was actually thinking of the Monacor midwoofer you linked to with that tweeter/waveguide combination for a cost effective hi-end studio monitor build but decided on the p.audio sn-8mb (series II) instead (http://www.bluearan.co.uk/index.php?...e=manufacturer). That p.audio driver is probably the best sounding midranger I have ever experienced when we're not talking dedicated full-rangers like Fostex or Lowther but those require horn loading and have terrible dispersion so they're not useful in a monitor build.

[axebay]

Ok, thought that it was the other way around :P
Then I can settle for 2 SP-6/100PRO, 2 DT-99, one LiFePO4 battery @ 7,2Ah but charger?
If I would mount a charger to to the battery and then to the AMP6, would the Amp get power from the battery or directly from the charger? I believe it's the first alternativ?...

[Saturnus]

A horn works by concentrating the dispersion that would otherwise have been lost and by transforming acoustic impedance from high at the throat to low at the mouth. In that way you a lower but more more uniform dispersion and an amplification by impedance transformation. In a sense the impedance transformation is similar to the effect a regular transformer has in an electric circuit.

[axebay]

Shouldn't I go with some sort of horn construction then, because of the outdoor use?

[Saturnus]

Not necessarily. The object is wide dispersion. And for a monopolar speaker is actually better to have as wide as possible dispersion which is achieved without a horn. For a bipolar speaker like the Boominator, too wide dispersion also becomes a problem as you'll get summing errors in the far off-axis field. Meaning it will not sound linear when listening directly from the ends. In a bipolar speaker high frequency dispersion is best limited to a uniform dispersion of between 90 and 120 degrees. But it has to be on all axii having different horizontal and vertical dispersion patterns will not sound natural but if a choice has to made it's more important with horizontal dispersion than vertical. As a limited vertical dispersion of say 60 degrees will only mean that it the speaker is not linear directly above (and below) it which isn't terribly important. More limited vertical dispersion than 60 degrees is not recommended.

[axebay]

Awesome! Think I understood your explanation about the horns. Also think I know all the big parts in my build:
2 midwoofers, 2 tweeters, 1 amp, 1 battery, cables, switches and etc. But I think I'll skip the pico-UPS since it only can charge with 500mA. For slightly more than half the price, of the picoUPS, I can get a 2A charger at the site were I'm buying the battery, so lower price and shorter charging time. If I would use the picu-ups I'd still need an ac/dc converter, so instead of the ups I'll use a simple switch. The only thing I'll loose is the smooth switching between powersources? But I save a litte money and can recharge the battery faster?


EDIT: Saw that the tweeters you recomended hade weight at 700g. Also tried to calculate the total weight and rounded it of at 12kg...
Perhaps these tweeters or these? Is afterall no Hifi-system that I'm building so to save 1 Kg is realy tempting:P

[axebay]

Decided to use these together with the Sp-6/100PRO. For this I will need a filter? Will a simple 2way filter be sufficient? A 0.33 mH coil for the 4 Ohm 6,5" and a 10uF condensator for the 8Ohm tweeters?