The Boominator - another stab at the ultimate party machine

I have been doing some more thinking about my halfinator.

I'm thinking 'bout making the halfinator in a standing design, with each HP-10W playing on different channels to get a decent stereoimage. I will though still make holes in the center bracing so that I can use one port for both speakers. Here are some non-detailed sketches I made in paint just to show how I'm thinking. There are currently two versions I'm thinking off.

1:
An externally hosted image should be here but it was not working when we last tested it.


2:
An externally hosted image should be here but it was not working when we last tested it.


Note that the right and left side will be identical, that will say 2x HP-10 in total etc. The back will not be identical to the front though, as there will be nothing there.

In the second version I'm thinking off using 2xHP-10 and 4xPiezo's. This is due that the low frequesies stays around the speaker, while the higher frequensies just travels straight away and will eventually get lost outdoors if you'r not standing in front of the piezo's. But if you sit in front of the port in the second version, I gues you will get:
* A decent stereoimage
* A decent soundimage, with both low and high frequensies.

Am I right?
Would you recommend any of theese two versions? Or would you go with another one?

I would be very pleased to hear your opinions.

All the best,
bekutori

What I'm hearing you describe is 2 speakers playing stereo, but in the same cabinet, right?
I'm no audio expert, but I'm pretty sure that this is listed as a "DON'T" in the Speaker building for dummies book :) - correct me if I'm wrong.

So if you insist on building a Halfinator, I think you should stick to one channel. But if I were you, I'd copy the original design, and make a true Boominator.

Happy building :)
 
Hey guys!

So i've almost gathered all the parts required to build a full-blooded Boominator!

Im thinking of a mod that i havent been able to see when searching the thread.
It is a so:
An externally hosted image should be here but it was not working when we last tested it.

Im planning on putting switches on the positive wires going to the 2 speakers on one side of the boominator. This drawing is very crudely drawn (no piezos etc. drawn), so in reality these switched would be placed on the front panel where we have all the other inputs.
My question is - Is this even safe for the speakers/amp? And if it is, would a regular flip switch like this do?

And lastly - if the switches are connected to the positive wires of the speakers AND turned on (so that the speakers are activated), would it have a noticeable effect on the sound quality?
 
So, me and a friend are gonna try and build a standard boominator, sans solar cells (might be added later though). I'm thinking about LiFePO4-batteries vs SLA and found this reseller (click Shorai in the left pane) in Sweden for a MC LiFePO4 called Shorai. Do you think these prices are competetive, 919 kr for a 7Ah battery 483 g and 113 x 58 x 89 mm, considering shipping is free when ordering two or more batteries or a battery with charger? On a MC-forum someone mentioned Bohemian Racing as a ok and cheap supplier, but they seem to be US-based (?) and I guess shipping over the atlantic is expensive and/or slooow.

I find different numbers on what voltage the LiFEPO4-cells delivers, guess it depends if you measure when just charged or a medium over their usage. But the highest I saw (for a 4cell pack) was 14,34 V fully charged and no load. and from the 41hz webshop the amp6basic seems to handel up to 14.5 V DC so I guess no problem, right?

Still reading trough the thread for the second time, to get it all straight. My friend studies electronic engineering and design so she's responsible for that part, but since she has little time over from school I'm the one who collects all the info. I've already placed orders for 4 p.audio HP10W and 4 MPT-001 tweeters from PLUS-Elektronik.d, and a assembled amb6 basic from 41hzaudio. Both these places seemed to have some trouble with their PayPal-accounts, which seems a bit funny since I've been using PayPal for a couple of years and never ran into that with anyone else. But we're in contact via email so everything will sort out I guess.

When calling my closest wood supplier for Wisa Form Birch plywood they claimed that they only had 'Wisa Form' in stock. Which is strange since there is no thing called that, or rather there is eight things called that, depending how you look at it... and one of them is the 'Birch' one. I guess that everyone who works at a place can't be knowledgeable of everything they have.
Did I understand correctly that 9 ply would give best acoustics and Birch would be the lightest kind of 12 mm? So that if I step down in veneer layers from 9 ply I sacrifice sound quality, and if I get another kind of wood than birch I gain weight?

Also, add me to the list of people who would pay for a easy-to-follow construction manual...:)
 
So, me and a friend are gonna try and build a standard boominator, sans solar cells (might be added later though). I'm thinking about LiFePO4-batteries vs SLA and found this reseller (click Shorai in the left pane) in Sweden for a MC LiFePO4 called Shorai. Do you think these prices are competetive, 919 kr for a 7Ah battery 483 g and 113 x 58 x 89 mm, considering shipping is free when ordering two or more batteries or a battery with charger? On a MC-forum someone mentioned Bohemian Racing as a ok and cheap supplier, but they seem to be US-based (?) and I guess shipping over the atlantic is expensive and/or slooow.

You can buy them directly from Shorai Europe
 
how come is this?

I am not planning on switching the speakers on and off while the amp is turned on. And im guessing when the connection is not fulfilled between the speaker and the amp, the speaker will draw no power.
Please correct me if im wrong!
If you have two speakers sharing the same airspace, you have to drive them both. Otherwise the open speaker will act like a hole in the box.
 
Of course. If you make the centerbrace without holes and have separate reflex ports on each side, it would be possible. I'd still not recommend it though.
Indeed. But i think i'll just ditch it. The plan were to make it double as a home stereo system (where i dont need 360* audio covering). But since the main purpose is to use it at Roskilde, im just going to ditch the idea. Thanks for the help
 
Hello everybody!
I'm new here, i started lurking this post some time ago, but it's sooo long, and i can't find the info i needed reading random pages of it!
I'm setting up a solar-powered stereo and i'm stuck at the amp!!!
Obviously i'm looking for a high power efficient digital amp. This have to be powered by the solar cells i already have. I've got more than one, quite powerfull, but they're not identical, i cannot use them in series so i'm stuck at 12V!!!
I was thinking about one or more TA2024 or similar for the mid-high tones, and this should be pretty fine (right?)! Now, i'm looking for a bit more powerfull low (maybe sub?) tones. But it's hard to find something that sounds good(read: loud) at 12V! Have you got any suggestion?
I found some TK2050 based boards that have rated voltage 10-32V, and claims 2x100W@4ohms.
BUT: would this TK2050 sounds louder than a TA2024 even on 12V?

OR: are there some other product that suits my needs and that i've missed?

I've also found some "class d/b" car amplifier made by rockford fosgate that claim high power efficiency and high spls at 12V, but they are kinda over powered and overpriced for this project!

Please help me!!!
 
PinkNoiser,

There is a theoretical limit to how much power you can get in an amplifier running on 12 v. The Tripath 2020 is about the limit at 15 wpc or so. Car amps work by using a switched mode power supply to raise the voltage, but these are going to suck some efficiency, too. There is a discussion here some months ago about running 2050 amps off 24 volts, but many who are building with that capability are putting a switch so they can drop down to 12v for efficiency's sake, as most people don't like the music super loud all the time.

Reports from those who have heard the Boominator are that it is LOUD. Efficient speakers make a huge difference, turning more of your amp's energy into sound. A small increase in dB makes a huge change in volume.

Go ahead and build one with a 2020. If you don't think it's loud enough, then you can switch to an electronic crossover (don't forget that this will suck some power too) and just use the 2020 for the highs.

--Buckapound
 
I was thinking about one or more TA2024 or similar for the mid-high tones, and this should be pretty fine (right?)! Now, i'm looking for a bit more powerfull low (maybe sub?) tones. But it's hard to find something that sounds good(read: loud) at 12V! Have you got any suggestion?
I found some TK2050 based boards that have rated voltage 10-32V, and claims 2x100W@4ohms.
BUT: would this TK2050 sounds louder than a TA2024 even on 12V?

OR: are there some other product that suits my needs and that i've missed?

Please help me!!!

IMHO you didn't miss anything. I use many tripath amps and the TK2050 gives a great, clean 50w @8ohms and 100w @4 ohms. it is very loud and it works at 12v. i power it with 14.7v li-poly batteries i buy from hong kong via ebay. these actually charge up to 16.8v. i like how this amp takes a wide range of voltages perfect for these batteries. These are durable amps. I use them on bicycles and they hold up to vibration! You can use this for your subs but i use these for everything when i go loud. I have not found its equal nor better.
 
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Many thanks for your faste replies!!!
Buckapound, i'm aware about the physical limits about SPL, for the istance, i would be satisfied even if the tk2050 is not worse than a 2024 in the same configuration.

So, if there aren't better alternatives, I think i will buy both 2024 and 2050 amps, due to the small costs. I will try both, eventually powering tweeters with 2024 and woofer with 2050, or just with 2050 (in this case i can eventually boost my system if not solar powered, with a 32VDC supply)

3 more questions now:
  1. I live in italy. Thats explains pretty much everything: why I want a solar powered stereo, why my english is so bad, and why I'm having hard time finding a close suppliers for equipments. I've planned to buy some assembled kits from Sure Electronics, shipped directly from china. Is this a bad idea? Do you know some better dealer, located somewhere in Europe? Do you think that shops like 41Hz would be better?
  2. Efficient speaker: the 360° layout doesn't suits my needing, so no magnet to magnet solution... I have no clue about high sensitivity speaker, not costy and shipped in urope with ease. Any advice? Maybe i could buy 4x 8ohm speaker and use 2 for each channel, this would increase efficiency? I've also seen some high sensitivity open baffle speaker. They have lots of cons (like 360° sound that is not fine for me), but also some pro: a well designed solution with open baffles would be very portable. Need you suggestions.
  3. Crossovering i was thinking 'bout active crossovers, with the hope that they would be more efficient than a passive solution. I would eventually build them by myself from spare components. Are there best alternatives? What about using a DPS? Would be good? Would be better? How much would i spend?
 
IMHO you didn't miss anything. I use many tripath amps and the TK2050 gives a great, clean 50w @8ohms and 100w @4 ohms. it is very loud and it works at 12v. i power it with 14.7v li-poly batteries i buy from hong kong via ebay. these actually charge up to 16.8 [...]

Could you do some testing for me? It would be great if you should test TK2050 at different voltages with the same input level, and tell me how much the spl vary...