Jack 10 Beatin' Up the Beach

[ncgrove]

Finally got the Jack 10 (Beta 10, 6 piezo flat array) out of the house this weekend and took it down to Padre Island for a day at the beach. Powered off of a Lepai 2020 (http://www.parts-express.com/pe/showdet ... %20tripath) amp, using an SLA battery for a power supply.

Just parked it on the tailgate, plugged in the ipod, and it killed. I swam out to the third sand bar, and I could still hear it crystal clear, bass and everything. It was a perfect rig. Oddly, the piezos cut out every once in a while, but fixed themselves after a few seconds, so I didn't really worry about it. It probably didn't help that the speaker, amp, and battery were sitting in the sun, and it was pushing 110 degrees outside. I was too busy enjoying cold beers to worry about it.

I only turned it off for a little bit in the afternoon when the beach turned into Jersey shore when a bunch of lifted trucks filled with D-bags pulled up and blasted their truck stereos. Luckily that didn't last too long. The one Jack running off of maybe 5 watts couldn't keep up with the thousand dollar custom truck stereos. Oh well... custom truck stereos drain custom truck batteries pretty fast. My 12 Ah battery went strong for at least 8 hours. I'll try to find out if anyone took pictures and throw them on here.

Thanks Bill for the awesome design!

[el_ingeniero]

Get yourself an Optima deep cycle battery, then you can run an 80 watt amp and give the custom truck sound sytems a run for their money.

[ncgrove]

Found a picture. It's the little green beast on the tailgate.

I'm sure the 80W amp would drive this thing to deafening levels, but the whole idea was to make a cheap tailgate/party rig. Did it all for under $200 and I can't imagine needing a bigger amp. If anything, I'll just build another box and stack em if I decide I need more volume. Should work just fine with just the little Lepai.

[el_ingeniero]

Sweet, I like the ocean green color, just like a cooler.

[ncgrove]

Yeah my girlfriend chose the color. I was willing, but naturally skeptical of the color at first, but I think it turned out pretty nice. I put two coats of Shirwin-Williams Multi-Purpose latex primer, followed by two coats of the green S-W latex enamel.

The paint got some dings on the trip (it's no duratex), but it'll be an easy touch up. I barely used any of the quart of paint I had made, so I thought I'd have enough to touch it up for a few decades. However, after I knocked over the paint can on my living room floor, I now only have enough to touch it up for a few years. Luckily, the hardwood floor survived the Great Green Paint Spill of 2011 without any permanent scars.

[bzb]

I did mine with red Sherwin Williams enamel in the horn and black Duratex on the outside. Been to quite a few Georgia Force games, a couple concerts, a couple outdoor wedding ceremonies, and we've even taken it out on Lake Lanier. Keep it in the shade and the thing bumps forever on a 12mAH battery and that Lepai unit.

This was day 1:



Paint still looks great now after being abused for a few months, and the Lepai, strap handle, and flip out leg mounted:

[ncgrove]

Keep it in the shade and the thing bumps forever on a 12mAH battery and that Lepai unit.

Yeah next time I'm going to make sure to park it where it won't get direct sun.

Have you noticed distorting of the bass frequencies coming through? It might be because I'm running the Beta 10, but it wouldn't put out as much bass as I'd like without distorting. Are you just using the two EQ knobs on the Lepai? My buddy running the ipod was playing mostly rap and top 40 stuff. I found myself tweaking the bass and treble settings for almost each song to avoid distortion.

That might just be a trade off for running the cheap system without a proper EQ. I'll take it though, because this thing kicks ass.

[bzb]

It's not the drivers, it's part the gain structure, and part the amp running out of power. I would get pretty bad distortion from my iPhone (original 8GB) if I went past around 60%. So I set the iPod volume control to 50% and cranked the amp gain up to max. Very rarely get a song with distortion in it.

[James R]

Those are really cool, nice job!

[ncgrove]

The Xmax of the Beta 10 is 3mm according to the Eminence spec sheet. How much power should this driver be able to handle distortion-free in the Jack 10 with respect to excursion limits?