Portable bass amp idea

[n4vgm]

I've been lurking a few years and learned a lot reading this forum but now I have an idea I wanted some suggestions on. Portable bass amp in a suitcase!

I'm thinking I can pick up a smallish funky old suitcase at the thrift store, put two high spl 4 ohm speakers in it, run it off 8 rechargeable AA's in a holder mounted inside and glue foam inside. The suitcase itself should vibrate some and give it some extra thump. I can even make it lean back or cut a port in the side. Problem is the amp.

Design goals will be to get as much clean volume out of 12v with minimal controls. All I need is a VOL/ON pot. I want to just plug right into it with an electric bass guitar to keep up with maybe a guitar and hand drummer.

I find amps like the Dayton Audio DTA-2 but those are for preamplified signals. I do have a Zoom B1 Effects pedal with stereo headphone level output. Even though I'd rather not use the Zoom just for simplicity, is the Dayton Audio DTA-2 actually the easiest way to go? 15 watts per channel into 4 ohms I believe, so I could get 2 4 ohm speakers for max output. The Zoom output specs are these.

Output(Line / headphones combined) : 1/4" stereo phone jack(Maximum output level : [LINE]+3dBm, output load impedance 10kΩ or higher / [headphones]20mW + 20mW, into 32 ohms load)

Am I right that the DTA-2 input wants 10K ohms or higher? Would running the Zoom stereo into the DTA-2 at say 80% volume be relatively clean? I'd have to get the highest spl speakers I can find of course.

Any other thoughts on what is the easiest way to do this? I have the soldering skills to make a couple of circuits, my problem is lack of time. I'm thinking that premade modules would even be cheaper these days.

Thanks in advance for your suggestions!

[geraldfryjr]

AA's probably won't last for more than 15 minutes at that power level.
If you are going to go that route you might consider a couple of small sealed Lead acid batteries as nicad's or rechargeable lithium's are quite costly.

jer

[n4vgm]

Thanks for the heads up on that, you are right. I could add a switching jack and a wall wart (may already have one). As long as I can get an hour or so on batts it may work out. I already have many rechargeable AA's and a smart charger so that would keep the cost down.

I see this speaker might be good, though 6 ohm=less output but very light!

Aura NS6-255-8A 6" Paper Cone Neodymium Magnet Woofer 299-030

[lduarte1973]

you should use a pro woofer something like this :

Pyle Pro PPA6 6-1/2" PA Speaker 292-210

[sreten]

Aurasound NS6-255-4A 6" Paper Cone Woofer 4 ohm: Madisound Speaker Store

Hi, it is good value and 4 ohm. I wouldn't use that Pyle unit for bass guitar, rgds, sreten.

[cyclecamper]

Use an Optima car battery and a switching-mode car stereo amplifier. And two small speakers. That way you can always add another battery, plug into a car, or use a charger. Add an extra capacitor across the battery too, so automotive chargers and alternators don't add noise.

[cbdb]

For low end, which you will need for a bass, the box the drivers are in can make a big difference. A suitcase might not cut it.

[n4vgm]

I'm thinking of a box shape so when I decide on the driver(s) I'll know what volume to shoot for. I found this one which might be a better alternative.

Goldwood GW-406D 6-1/2" Poly DVC Subwoofer Shielded 290-352

Running each channel into it's own voice coil at 4 ohms and still be way under the speaker wattage.

[Keriwena]

Guess what's going to happen to that foam surround the first time you slap the E?

It's a cool idea, but if you want it to be cool in practice and not goofy:

As cyclecamper said, give up on the idea of flashlight batteries.

Put a piece of plywood inside the suitcase so you have a real baffle to mount the speaker.

Use a real bass guitar speaker, like this:
Eminence Legend BP102-4 10" Bass Guitar Driver 4 Ohm 290-470


You still might need to glue Masonite or something to the other sides of the suitcase, the cardboard will leak like sieve. You also might consider putting the preamp in your guitar - active basses are cool.


If you really want to try and get by with a cheap hifi speaker, then you need to send it a "hifi" signal - compress it, limit it, and EQ it. (All of which you can probably do with the Zoom.) But it will, at best, sound like a loud boombox. To sound like a musical instrument, you need a musical instrument speaker.

[n4vgm]

Well, after looking around for other folks doing this (suitcase bass amp) I have come to the conclusion that the reason no one has done it is that it will sound like c**p! Bass cabs sound best when they are very ridged and I doubt I could brace a suitcase enough so as not to sound like mush!

Thanks for the help anyway, maybe someone else will give it a go.