Jack 15 Lite Build

[Bill Fitzmaurice]

The throat sheaths are harder to bend because they have a tighter radius. One way to help that job is to insert a long clamp through the port to pull it into place.

[Benflitv30]

I will do that on the next one, Bill. Thank you.

Tested this cab out without the tweeters just for fun. Been exploring more amplifier options for more output. Currently has the Kappalite 3015 wired to a 2x50wrms (rated at 4 ohms) amp board for first demo. Likely getting around 20 watts.
A 4 ohm woofer would certainly help squeeze more out of an amp ‘module’/battery powered application like the Dayton product posted earlier, but want similar quality to the Kappalite.

What about this option? -
https://www.eighteensound.it/en/product ... %204%20ohm

Any good or bad experience with the brand?

[Bruce Weldy]

I will do that on the next one, Bill. Thank you.

Tested this cab out without the tweeters just for fun. Been exploring more amplifier options for more output. Currently has the Kappalite 3015 wired to a 2x50wrms (rated at 4 ohms) amp board for first demo. Likely getting around 20 watts.
A 4 ohm woofer would certainly help squeeze more out of an amp ‘module’/battery powered application like the Dayton product posted earlier, but want similar quality to the Kappalite.

What about this option? -
https://www.eighteensound.it/en/product ... %204%20ohm

Any good or bad experience with the brand?

Can't answer your question about the driver, but if you already have the Kappalite in there, why not spend the money you'd put out for the 18Sound and just get a bigger amp?

I honestly don't think that swapping the two drivers will make any noticable difference with that little bit of power.

[Bill Fitzmaurice]

You've got the equivalent of a thirty five foot cabin cruiser being powered by a ten horsepower outboard motor. See the problem?

[Seth]

All else being equal, going from 8Ω to 4Ω will only gain 3dB, where properly powering the 8Ω driver will gain 7-10dB. Money spent on amplification is definitely more appropriately spent.

[Benflitv30]

You've got the equivalent of a thirty five foot cabin cruiser being powered by a ten horsepower outboard motor. See the problem?

That’s a perfect analogy, Bill and well received as an owner of a boat restoration business in Florida. Haha. The idea of maximum portability by not lugging around a generator is just beyond attractive. I digress.

Was looking over the Dayton plate amplifier stickied in the forum.
https://www.parts-express.com/Dayton-Au ... th-300-798
I couldn’t imagine the output of this Jack 15L being fed with 300 watts. Not to mention with either the Dayton amp module or this plate amp, they both have DSP, so no need for crossover components as well.

If I were to mount this centered on the back panel, do you suspect I may have to do some creative bracing to ensure proper rigidity? At a 1/4” deeper than the braces, will have to check clearances of the woofer motor as well.

[Benflitv30]

Thank you, Seth and Bruce. More power over new driver wins.

[Bruce Weldy]

Thank you, Seth and Bruce. More power over new driver wins.

I have one of those amps, it can handle the crossover for you too. However, I doubt seriously that you'll be able to fit it in there at all. If I remember my Jack 15 build, there's no way it will go between the driver and the back cover. Consider buildintg it onto the back cover in a separate enclosure. All you really have to do is attach four "walls" for it to sit in. That way it won't interfere with the driver or the bracing.....and would be way easier.

[Seth]

...This Jack15L will have the 20 melded tweeter array. Going to put the 3-way switch on the tweeters for versatility in listening environments. All those tweeters I’m sure will come in handy on a boating day out on a wide open sandbar. Otherwise will be used for tailgating at games and bbq’s etc.

A little advice on this... If you are using the cab purely for music playback, there is absolutely no reason to use a switch on the tweeters. I know there's a lot of them, but it's intentionally that way. Designed that way for balanced sound. It's not the type of thing that you'd turn some off for tailgating and turn some on for the sandbar. They should all be run all the time.

Also, the Dayton amp module you posted should work well for you and allow you the option of running off battery. Having integrated DSP would allow you to tune the heck outta the cab, providing jaw dropping results if you really take the time to tune it well. Forum member KarterCraft used one in his O12 Tall Boy build, powered it with a cordless tool battery, and has reported great results. Makes it a cab that can easily be used anywhere. In your case, it would still require a few passive crossover components for the tweeters, which I'm pretty sure is covered in the plans.

[Clef's of Bass]

Super cool build so far.

[Benflitv30]

Practically fully completed this cab. Is it perfect? Not by far. I am glad I took on the challenge though and will be better off for the next build. It needs the glue residue taken off the tweeter faces, even though I used wax paper on the jig. Maybe too much glue. Some touch up Duratex, etc.

You can see it is powered by a Milwaukee M18 tool battery which feeds a Dayton 4x100 watt bluetooth amp module. I bridged two of the channels for the woofer. I am pretty happy for casual listening by the pool and such. Many fellow listeners were also impressed by it. I wired the tweeter crossover with the ‘less bright’ resistor option, yet it is still plenty loud in the highs department. The bottom end obviously suffers from lack of power. The amp certainly needs EQ work to reduce the bottom end. The Apple Music preset EQ functions are decent in the meantime. I run it on the ‘reduce bass’ setting. The vocals are incredibly clear and defined even at 75’ away with such power.

Trying to figure a power and amp solution still as the temptation to turn it up is mighty strong. Very apparent this cab has much more to offer if given what it wants in terms of power. The plate amp is the obvious best fit, but lugging around a power station or generator is not. Will either do a custom LiFePO4 pack built in an ‘add on’ back panel with a step down converter for a 12 volt amp or something else. The Sure Electronics modules don’t make much true power at 8 Ohms without much higher voltage. I just strongly prefer a one box self contained cabinet…a boombox so to speak. Any other power/amp ideas are welcomed!

For fun, I had it running in a standard cab F-150 truck with the doors shut. Wow, the cabin gain is unreal!! It’s wild the responsiveness/punchy nature this cab has. Could only imagine if an AutoTuba of sorts would be as punchy and loud (yes, I know it’s a much different design)?

[Tom Smit]

Well done!

[Seth]

Hey! Great job! Perfect party boom box

That amplifier should have plenty of power for that cab. The battery voltage is limiting the amplifiers output capability. If you wire a second M18 battery in series, the amplifier will likely put out 4x the power it currently does, which equates to +6dB maximum output potential, slightly less than twice the current perceived volume max. I'd recommend you add a second battery before trying anything else.

Alternately, you could try a voltage boost converter like CarterKraft used in his Omni 12 Tall Boy Build to get the voltage up. However, a second battery would be my choice.

If you haven't read it already, that Tall Boy thread is a good read and has lot's of tuning advice pertinent to your project too.

Once you get that done, you can use your smartphone and a free RTA app to dial in the EQ. Once you get that set all tasty, you can use the "Super Bass" plugin to fool your ears into thinking they're hearing subwoofer frequencies for a nice full sound.

Please keep us posted as your project continues and feel free to ask as many questions as you like along the way.

Again, well done

[Clef's of Bass]

Looking good, and especially cool for a mobile audio solution!

[9830Lark]

What did you use for the "jack" to hold the tool battery? Did you 'harvest' what you needed from an extra charger base?

Very intriguing. I'd love to build a separate box with BT that could be powered by my Ryobi 18v battery or batteries for music listening outdoors through my Jack.

[Edit]

Shame on me, ha ha. I found this in less than a minute https://www.amazon.com/Adaptor-Battery- ... GhlbWF0aWM

[/Edit]