Want to build a portable ipod boombox.

[GuyPanico]

My idea (I know some have done this as well) is to make a small portable boombox that I can dock my iphone to. I want it to be able to play at a moderate volume and have full sound. I want to keep the footprint to about the size of a standard keyboard or slightly larger.

For simplicity and cost sake, I think i'm going to use a sonic t-amp. For drivers, I am thinking about using a quartet of ported Aura NS3's. Two on each side running full range. I'm not worried about C-C wavelength interactions. I will probably be using this mostly in places where there is background noise, and I will not be facing it much of the time.

Will the pair of NS3's wired to 4ohms output fairly impressive sound with the t-amp? Now I need to research some easy mods to improve the sonic t-amp. I know nothing about electronic parts and how they work, so this limits my modification complexity.

Thanks!

[planet10]

Originally posted by GuyPanico
NS3... easy mods to improve the sonic t-amp. I know nothing about electronic parts and how they work, so this limits my modification complexity.

Also consider the Fostex FF85k.

Audio Magus sells the Trends T-Amp with various levels of mods (conceived by our own panomaniac)

dave

[Fast1one]

You won't be disappointed in a small room, but in a large room they may leave more to be desired...Consider running them in a bipole configuration, one in the rear and one in the front...an MLTL would probably work well

[pjanda1]

How about the Tang Band W4-1052SA? You might get slightly more sensitivity, but it should be able to do much better in the bass. It'd be cheaper. The cab might be bigger than you are looking for, though. Two TB 3"ers will give you a considerable efficiency advantage. Or, you could even consider a 1.5 way and have some real midbass via the BSC. I like the Tang Band look, but that's a matter or personal preference.

pj

[Saturnus]

Originally posted by Fast1one
You won't be disappointed in a small room, but in a large room they may leave more to be desired...Consider running them in a bipole configuration, one in the rear and one in the front...an MLTL would probably work well

Where on earth did you get that idea?

[GuyPanico]

In this case, what would the benifits be with a bipole design as apposed to a standard monopole? Wouldn't I lose a little bit of volume with the drivers mounted on the rear instead of the front as well?

I forgot to include this plot in my original post...

[Fast1one]

GAH! Disregard my post, I forgot this was for a boombox! Thats what happens when you have multiple windows open

Cheers,
Sergio

[Saturnus]

Originally posted by Fast1one
GAH! Disregard my post, I forgot this was for a boombox! Thats what happens when you have multiple windows open

Actually your suggestion about a bipolar design of a boombox is genius. I've used it for years because it some distinct advantages that is almost impossible to get otherwise, and it practically has no disadvantages.

You might think it would be difficult placing them indoors, but the point is that you should ignore that they have backfacing speakers indoors, and just place them 10-20cm from a wall preferably on a shelf or table. And outdoors just place on the ground.

I think I've outlined the advantages in my Boominator thread but to recap it linarizes the frequency response both when used outdoors and indoors because of the positioning acting as a natural acoustic x-over.

[sreten]

http://www.partsexpress.com/projects...zuma/index.cfm

Hi, worth a perusal and rather louder than 4 x NS3's, /Sreten.

[Fast1one]

Originally posted by Saturnus


Actually your suggestion about a bipolar design of a boombox is genius. I've used it for years because it some distinct advantages that is almost impossible to get otherwise, and it practically has no disadvantages.

You might think it would be difficult placing them indoors, but the point is that you should ignore that they have backfacing speakers indoors, and just place them 10-20cm from a wall preferably on a shelf or table. And outdoors just place on the ground.

I think I've outlined the advantages in my Boominator thread but to recap it linarizes the frequency response both when used outdoors and indoors because of the positioning acting as a natural acoustic x-over.

I am flattered! I actually considered building one with four woofers, but I wasn't sure if it would work well outdoors...

I know it would work well indoors, as that was my original intention, no need for a BSC, good bass response, and relatively cheap...

To the OP, this is what I originally intended http://www.mcminone.com/product.asp?...me=MCMProducts

Unfortunately it is out of stock, but as you can see its fairly efficient.

I designed a bass reflex enclosure, the two drivers would be braced with a threaded rod, port in the front...

16.8 liters for each pair, tuned to 62 hz, F3 is 72hz.



That plot is for one driver. As you can see it would be good with about 8-10 watts for each pair, won't be very loud, but loud enough I think, with little power requirements (could be powered my an AMP3 for example). Its not perfectly flat, but I wanted as much extension as possible Ignore the second half of the graph, bass box pro is not a good estimator of the higher octaves...

It would need a high pass filter to avoid over excursion down low unfortunately..