The Boominator - another stab at the ultimate party machine

We use an Amp9-Basic, but we connect channel 1-2 and 3-4 together to act as only 2 outputs to play louder (I believe), så then there would be no available output for a subwoofer. But why not install a mono amplifier and battery in the subwoofer itself, making it an active subwoofer that doesn't drain the Boominator's battery? :) That's our plan for next year.

Otherwise I like your idea of splitting the Boominator in two!
 
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Hi ThokN,
yes, using the AMP9 seems to be a good choice for "upgrading" the maximum output power by using higher supply voltage. My concept now looks like the drawing in the attachment:
- The left half-Bomminator is the "ultra mobile" part. So only amp9, battery and one pair of chassis and maybe a battery charger. The double switch is for switching between battery use or power supply use (and charging)
- The right half Boominator contains a power supply with e.g. 24V/10A
 

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The AMP9-B has four outputs and four inputs. If you connect it according to your schematics, then the amp will fry. If you have a signal connected to an input you also need to have a load on the output.
This can be a problem in your situation. If you disconnect the right-boominator, then you need to connect a dummy load to the output instead. If you forget to do this and start playing music the chip will be damaged.
You can also have both left and right channel in both the left and the right boominator, so the load just goes from 4 to 8 Ohm when you disconnect the right-boominator. The problem with this is that you have a magnet-to-magnet setup but with two different signals, unless you build two separate compartments in each boominator for the drivers and piezos.
A third solution is to parallel and go for mono instead of stereo. Then you will always have load on the channel (2 or 4 Ohm), and your magnet-to-magnet drivers will play the same signal.
There might be a better solution, but I'm a novice when it comes to audio, and have yet a lot to learn.
 
Noob Build

Hi everyone,

I was hoping to make a portable boombox for our dance group. Based on this thread, I've come up with the following part list,

1 Goldwood GW-1058 10" Pro Woofer (PE)

1 Constant Directivity Horn (http://www.parts-express.com/pe/showdetl.cfm?Partnumber=270-049)

1 LFP Battery (12.8V, 1.8 Ah) (Customize LiFePO4 14505 Battery: 12.8V 1800 mAh ( 23Wh, 4S3P Flat Pack, 2A rate))

1 Smart Charger (Smart Charger (0.7 A) for 12.8V (4cells) LiFePO4 Battery Pack, 100-240VAC, CE listed)

Total costs so far: ~$110

I know I still need an amp, and that's where the difficulty comes in. Since we don't really use stereo sound, we only need a mono amp. However, we need to get as much power as we can out of the amp, matching the drivers/tweeter. This is because there are several dance groups in the area we practice, and sometimes we can barely hear our music.

Based on the specs on my driver/tweeter, I would want an amp that is 1x200W, correct? at 8 ohm or 4 ohm, as one could parallel the driver and tweeter? Does anyone know where I could find an amp like that? (class D, of course, preferably based on TA2050 chip? or something like that). Thanks for your help.

Also, does that battery have enough playing time for ~ 10 hours at a high volume?
 
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Hi, I am planning to do a small boom box out of two 6x9's with a T-amp. Is that a good idea? Will I be able to play loud enough? The reason I am not building a boominator is because it's too heavy, and I am boot very good at building stuff...

Are 6x9's typical car speakers? If so, don't. Why not use car speakers for a boombox?

You can always build a half boominator, if the big version is to heavy.
Just don't expect that you will get the same sound from boxed car speakers.

If you want a small speaker, then the the Monacor SP 60 are liked by many. I don't have any experience with it myself though. SP-60/4
 
Could I build a halfinator with a SMSL A1 TA2021B T-AMP 2X25W Tripath Class Stereo Integrated Amplifier gold new | eBay ? Is there a drawing available of the halfinator?

Search and ye shall find :D

Rubenn's sketch-up drawing of a half boominator version is first hit if you goggle "half boominator" ;)

It's not how I would have made it but it gives a good idea to how to make one if you compare with the drawing for the original and then do some adaptations to suit your purpose the best. Only thing that you must not change is the internal volume where the speakers are mounted and the port tunings, though the latter could be done in a number of different ways.
 
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Search and ye shall find :D

Rubenn's sketch-up drawing of a half boominator version is first hit if you goggle "half boominator" ;)

It's not how I would have made it but it gives a good idea to how to make one if you compare with the drawing for the original and then do some adaptations to suit your purpose the best. Only thing that you must not change is the internal volume where the speakers are mounted and the port tunings, though the latter could be done in a number of different ways.

Thanks!

I have another question. Some boomboxes have the magnets glued together, and some have 8 holes, how do you choose which way to do?

EDIT: My t-amp has 2 inputs for speakers, left and right. How do connect my four speakers to the T-amp? I am a bit new to all this...

EDIT2: I am trying to choose which 2 piezo tweeters that I am going to use, but it is very hard. Can some one help me out a bit? I am ordering them from ebay. Does this par do the job: http://www.ebay.com/itm/DJ-PA-Profe...554?pt=LH_DefaultDomain_0&hash=item4ab0de6fe2 ?
 
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Thanks!

I have another question. Some boomboxes have the magnets glued together, and some have 8 holes, how do you choose which way to do?

EDIT: My t-amp has 2 inputs for speakers, left and right. How do connect my four speakers to the T-amp? I am a bit new to all this...

EDIT2: I am trying to choose which 2 piezo tweeters that I am going to use, but it is very hard. Can some one help me out a bit? I am ordering them from ebay. Does this par do the job: DJ PA Professional Boom Box Piezo Tweeter Speaker Pair | eBay ?

the "8" holes are just something that strengthens the construction. The boominators using this will be more rigid that the ones without, but the magnets are still glued together in order to add even more mechanical strength :)

the two inputs are just for left and right.. read this thread and you will find how to connect your speakers. (In principle you just connect all speakers from the left side to one of the inputs and all the speakers from the right to the other input. You will however need to make a simple filter in order to match the frequency response of the tweeters and the bass unit. You will find extremely many references to the right wiring scheme in this thread. It will take some time to read it all through but it will for sure save you some time in the end)
 
2 more questions:

1. I wanted to hear what the final conclusion was on what to do when connecting the HP-10W, since they aren't as deep as they used to be. Is it like rubennn did here: http://www.diyaudio.com/forums/clas...b-ultimate-party-machine-194.html#post2617367 - or is there a smarter way?

2. Since we've decided not to let the boominator kill us, a fuse from the battery, as explained previously, would be needed, but how big a fuse?
 
I have decided to go with 2 P.audio HP-10Ws and two QLM-1005s.

The stats for the woofer:
Effect: 100 W RMS.
Sensitivity 96 dB.
Frequency 50-4000 Hz.
Impedance 8 Ohm.
Recommended cross over frequncy 90-3000 Hz

The stats for the piezos:
Effekt 300 W.
Sensitivity. 95 dB
Frequency. 4000-40000 Hz.

As you can see the recommended cross over freuency for the woofer is 90-3000 Hz, which is quite a big "scale". For me it is hard to know what is appropriate. I read somewere in this thread that 1,5khz wold be enough, would it?

EDIT: But here: http://www.sweclockers.com/forum/78-gallerikommentarer/993733-boominator-orange-feeling/ the guy is using 250Ohm 5W, hm?

EDIT2: The guy in the link above said that he removed his resistors, and i still sounded OK? How come? If so, why are you all using cross overs? Now, I am confused!
 
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im about to make a boombox with:
2x HP-10W
2x Piezo tweeters (i dont know which im going to buy yet)
1x Amp6-basic
7,2aH Pb battery

For the tweeters/piezos ive been thinking about these: Monacor DT-100 .. i can get them for like half the price.. or should i go with piezos like these | IMG Stage Line 110530 |Piezohorn MPT-165 Hjttaler-enheder Piezo Diskanter or any of the other one from discoworld.dk ?

Im planing to build one like this: marine core theme boombox - YouTube so it will be on a size so i can take it with me in a bus ..

Hope you can help me, and thanks for alle the threads!