The Boominator - another stab at the ultimate party machine

[buddaertyk]

It's not because I wanna be to inoying. but I would be very happy if one of you guys want's to tell me how I maybe could make an okay Boombox that would be able to last quite a while. im probably the only one with this question in this tread.
But I would be so happy and there would also be a camp at Roskilde and Jelling that would be so much better

From a hopefully Buddaertyk.

[ThokN]

Hello Saturnus. We've build a Boominator for Roskilde 09, and it was a huge success. This year we are planning on making it a bit more powerful, so I have a couple of questions to your planned changes for your new Boominator.

Originally Posted by Saturnus

I'll be making some minor changes though, like adding a phase plug with a rod that will connect the 2 speakers mechanically through the center.

What effect will this have?

Originally Posted by Saturnus

The amp6basic is going to be replaced with an amp9basic

I've been thinking of doing the same, but do you know if it will be as easy to implement, as the Amp6-Basic? I think we are going to have it build for us, so I'm talking about if it will work 'out-of-the-box' with two 12v batteries in a similar way to the amp6-b.

Originally Posted by Saturnus

and it's going to run on LFP cells instead of SLAs.

What impact will that have on the performance of the Boominator compared to SLAs?


I'm looking forward to see the new Boominator!

[ThokN]

Originally Posted by buddaertyk

It's not because I wanna be to inoying. but I would be very happy if one of you guys want's to tell me how I maybe could make an okay Boombox that would be able to last quite a while.

I don't think there is any guide, if that is what you are thinking about. You should read this thread, which would probably give you all the information you need, although I know there are a lot of different suggestions and strange numbers to comprehend. If you make one which is roughly the same as Saturnus' original Boominator, then it should last a very long time, both physically and battery wise.

I small to-do list/guide would probably be like this:

1. Look at the pictures of Saturnus' Boominator to get an idea of what it is and will look like. (Two speakers and tweeters on each side, a seperate compartment in the middle for batteries and amplifier. The speakers are glued together magnet-to-magnet to enhance efficiency, and held in place by a piece of wood in the middle of each of the two speaker compartments, but without seperating the compartments, since they should share the volume (I think it's about 23 liters or something). Read and understand parallel and serial connections of the speakers and tweeters.) This is the way we did it, but Saturnus' internal design probably differ somehow.

2. Find it's dimensions in this thread, and get the wood needed to make the box.

3. Find the parts needed. (i.e. amp6-basic, 4x HP-10W speakers, 4x Zomax piezo tweeters, speaker cables, mini-jack cable for mp3-player, 12v SLA battery/batteries, amorphous solar cell that will fit the dimensions of the boominator if built in.) There are other stuff needed too, like volume knob, resistors for tweeter crossover and stuff, but you will find these while reading the thread.

4. Start building! Since there's no guide, you will probably have to do some things your own way, like fitting the solar panel, the batteries etc.

I would probably recommend getting one of the 41hz.com forum users to build the amp and send it to you. We fried ours when testing it, but i think V-Bro build ours perfectly for a small fee.

Hope this helps. You will still have some reading to do in this thread, though

[ThokN]

Oh and btw. In a setup like the Boominator, will an Amp9-Basic be significantly louder than the Amp6-Basic? I've tried to understand percieved volume, watts and dB, and as I understand it, the total watt increase from 2x25w to 4x50 will give a boost of 6dB, right? I'ts just hard for mo to understand if 6dB is that much of a difference outdoors like at Roskilde for example.

I guess the 4x amount of power used, will result in less than double the percieved volume(which would be +10dB)?

[Saturnus]

Originally Posted by 17DoubleE

Hey everybody,

I've read and re-read this message thread and like many of you, have the bug to build one. Hats off to Saturnus for the skillful design work and for sharing it with us.

I like the design details of your Boominator, Saturnus, and with your permission plan to pattern mine off of your design.

I'm from the USA where I can't seem to locate either the HP10W or the Zomax HP100 piezos. From this thread, and a review of the specs on the partsexpress website, I understand the GW-1058 to be a suitable substitute for the HP10W. I read the discussions about a few other tweeters, but didn't see recommended a substitute tweeter that's on par with the HP 100.

Do any of you have a recomendation for a good-sounding tweeter like the HP 100? Is there an even more efficient speaker than the GW-1058 (with appropriate specs) that is not too terribly expensive?

Thanks, Bill

Thanks a bunch mate. And no, I have no problem people copying the boominator or using it as inspiration for their own design.

It's possible you could find something that would equal or be better than the HP10W/GW1058s in price, efficiency, or sound quality but I doubt you can find anything that will equal them in all 3 at once.

There's no piezo I know of that can do what the Zomax HP100 can do but a suitable replacement would be Parts-Express.com:*Constant Directivity Horn | super tweeter tweeters tweeter ir horns horn tweeters horn tweeter horn CTS although that would require making a simple filter.

Originally Posted by Love Below

Have you startet on your new boominator saturnus?

Yes Finally.

Originally Posted by ThokN

Hello Saturnus. We've build a Boominator for Roskilde 09, and it was a huge success. This year we are planning on making it a bit more powerful, so I have a couple of questions to your planned changes for your new Boominator.

Glad to hear it

Originally Posted by ThokN

Originally Posted by Saturnus
I'll be making some minor changes though, like adding a phase plug with a rod that will connect the 2 speakers mechanically through the center.

What effect will this have?

Even more mechanical stability (as if that was really needed), and hopefully a bit better dispersion in the higher mid-range to match the tweeters.

Originally Posted by ThokN

Originally Posted by Saturnus
The amp6basic is going to be replaced with an amp9basic

I've been thinking of doing the same, but do you know if it will be as easy to implement, as the Amp6-Basic? I think we are going to have it build for us, so I'm talking about if it will work 'out-of-the-box' with two 12v batteries in a similar way to the amp6-b.

More or less, you'd probably need a set-up trafo to get the gain high enough to match an iPod, if that's your source. Alternatively you could try an integrate a docking station with built in preamp (maybe even remote controlled).

Originally Posted by ThokN

Originally Posted by Saturnus
and it's going to run on LFP cells instead of SLAs.

What impact will that have on the performance of the Boominator compared to SLAs?

LFPs are half the weight for the same capacity, they can be fully recharged in under one hour, and they last at least 10 times longer (meaning they can be recharged more than 10 times more times before starting to wear) in fact they can probably last 30-50 years in a design like this were you don't recharge that often where SLAs most often don't survive a season intact.

They're also completely safe in every way. Much more so than SLAs or any other kind of battery.

Originally Posted by ThokN

I'm looking forward to see the new Boominator!

As am I.

And now I have a question for you folks out there. Is there someone who can permanently host a small file, if so then I'll put up the "easy-build"-version Google SketchUp drawing of the original Boominator for all to use.

[Saturnus]

Originally Posted by ThokN

Oh and btw. In a setup like the Boominator, will an Amp9-Basic be significantly louder than the Amp6-Basic? I've tried to understand percieved volume, watts and dB, and as I understand it, the total watt increase from 2x25w to 4x50 will give a boost of 6dB, right? I'ts just hard for mo to understand if 6dB is that much of a difference outdoors like at Roskilde for example.

I guess the 4x amount of power used, will result in less than double the percieved volume(which would be +10dB)?

Doubling the power would actually only give 3dB more. But I'm not actually going to use it in 24V mode. I'm going to use some other tweeters intirely so I need a passive line level filter (PLLXO) with some more ingenious tweaks of my own invention (I think, at least haven't seen it before).

[ThokN]

Quote:
Originally Posted by ThokN View Post

The amp6basic is going to be replaced with an amp9basic

I've been thinking of doing the same, but do you know if it will be as easy to implement, as the Amp6-Basic? I think we are going to have it build for us, so I'm talking about if it will work 'out-of-the-box' with two 12v batteries in a similar way to the amp6-b.

I was more thinking about the fact that Amp9-b has 4 output channels, while Amp6-b has 2. And because of the genius parallel-wiring of the Boominator, it was actually favorable to have only 2 outputs for 4 speakers, so the speakers went from 8ohm to 4ohm. But...

...will this work on the Amp9-b? I understand that it is possible to only use 2 channels of the Amp9, but does that mean that it will become 2x100W instead of 4x50W? If it will only be 2x50W half of the watt will obviously be unavailable to us.

But if we connect a speaker to each channel, it will not be possible to parallel-wire them as we do now, losing the big advantage of 4ohm.

Can you confirm this? Or is there a way to wire it all up in a way that will provide the full total 200W, while keeping the speakers paralleled for 4ohm?

Doubling the power would actually only give 3dB more. But I'm not actually going to use it in 24V mode. I'm going to use some other tweeters intirely so I need a passive line level filter (PLLXO) with some more ingenious tweaks of my own invention (I think, at least haven't seen it before).

What is the reason you are not using it in 24V mode? That was my original idea to begin with, to get the maximum power for the speakers, resulting in higher volume, right? We have 2x 12V SLA's in our Boominator, so we could just wire them in series to get 24V. I don't suppose this will use more power when at same volume levels as our old 12V solution.


Sorry if these are stupid newbie questions, but I am still a newbie to this

[ThokN]

Originally Posted by Saturnus

And now I have a question for you folks out there. Is there someone who can permanently host a small file, if so then I'll put up the "easy-build"-version Google SketchUp drawing of the original Boominator for all to use.

I've just talked to a friend of mine, also involved in our building of our Boominator, and he has a webserver and would be happy to host the file for you. If you could upload it somewhere, he could download it and store it on his server permanetly? If you just give me the link in here.

That would be so awesome

[ThokN]

What are your thoughts on this speaker?

TRUVOX-0818MR

They are at 102dB! This would be a huge percieved volume boost from 96dB right?

It is only 8", but 100W RMS as with the HP-10W.

[Saturnus]

Originally Posted by ThokN

What are your thoughts on this speaker?

TRUVOX-0818MR

They are at 102dB! This would be a huge percieved volume boost from 96dB right?

It is only 8", but 100W RMS as with the HP-10W.

It's a midrange driver. Resonance Frequency at 450 Hz meaning it won't play anything below that.