I recon that it means that the sound will be 105-107db loud when standing 1 meter from it? - Isnt that okay loud?
I still dont get why 4 x P.Audio P10W makes it 4ohm, when 2 x P10W are 8ohm, im really confused by that
I recon that it means that the sound will be 105-107db loud when standing 1 meter from it? - Isnt that okay loud?
I still dont get why 4 x P.Audio P10W makes it 4ohm, when 2 x P10W are 8ohm, im really confused by that
Yea, its quite nice.. It will be far far superior to any storebought ghettoblaster
Hmm okay, ill give you a very brief explanation of the impedance question.. Imagine you have a painter, he can paint your room in 8 hours.. If you add a second painter (like you parallel 2 speakers) which can paint the room in 8 hours and they do it together, they can do it in 4 hours.. Makes sense?
If you lower the impedance of the woofers by paralleling them you'll give your amplifier a smaller load and it can therefore perform better..
Then you might think - AHH BUT HOW ABOUT PARALLELING MORE FOR 2 OHM OR 1 OHM FOR MOAAARRE EFFECT?!
That would be possible, however if you dont provide the amp with enough resistance it will be like riding your bike downhill in a low gear trying to make the pedals propel the bike forward = disaster in short..
2 ohm is possible with something like the Amp6, provided with enough cooling, but you'll be treading on thin ice if you dont know what you are doing
Hope that helped a bit!
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Hahah! Phaedras you just made me think of these old pictures
I believe that it hurts your ears at around 120 dB and up from there.
An externally hosted image should be here but it was not working when we last tested it.
I believe that it hurts your ears at around 120 dB and up from there.
It won't even do 12W into 8 ohms under normal circumstances.
Remember the formula from before. You can just reverse that and see what voltage it needs to get 12W.
supply voltage = Square Root ((12W / 0.9 (efficiency)) * 16 (double impedance)) = 14.6V
14.6V is the absolute maximum rating of the chip, and far above what a car battery will provide.
Yea, its quite nice.. It will be far far superior to any storebought ghettoblaster
Hmm okay, ill give you a very brief explanation of the impedance question.. Imagine you have a painter, he can paint your room in 8 hours.. If you add a second painter (like you parallel 2 speakers) which can paint the room in 8 hours and they do it together, they can do it in 4 hours.. Makes sense?
If you lower the impedance of the woofers by paralleling them you'll give your amplifier a smaller load and it can therefore perform better..
Then you might think - AHH BUT HOW ABOUT PARALLELING MORE FOR 2 OHM OR 1 OHM FOR MOAAARRE EFFECT?!
That would be possible, however if you dont provide the amp with enough resistance it will be like riding your bike downhill in a low gear trying to make the pedals propel the bike forward = disaster in short..
2 ohm is possible with something like the Amp6, provided with enough cooling, but you'll be treading on thin ice if you dont know what you are doing
Hope that helped a bit!
Oh that makes sense, im still about confused about why more unites means less work for the amp, but now I see the basics behind it.
To make a long story short, 2 x P10W with NEW CLASS Amp SA-36 TA2020 Amplifier Tripath Chip | eBay UK would be a FAR better choice than any boomblaster?
Haha now you are making me nervous again man
I dont wanna show up with a shitty boombox that makes absolutely no noice at all I really must advice against the LePai AMP. I bought two of them of Ebay while experimenting with the boominator: both of them stopped working while playing at loud volumes! AMP6 is still delivering! =)
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YouTube - Boombox with built in VU-meter
The “Malen” Boombox « Popdevelop – A developer team from Malmö, Sweden
I haven't had a Lepai yet, but S.M.S.L. worked fine for me last year. That's also almost as cheap as Lepai. Never stopped working for me
Haha now you are making me nervous again man
Remember that Boomblasters also run on batteries, right? And they also run on 12V batteries (10 D cells in series under load = 12V), so the same formula applies to those. Except they use crappy small very insensitive speakers and not professional 10" woofers.
A boomblaster has a maximum output of 99dB. That's what your HP-10Ws will have when it uses 2 watts. So it will actually play twice as loud the largest version of the JVC Boomblaster, the KA-Boom.
The real Boominator will play 4 times as loud. And go far lower in bass, and have far better sound quality.
Hmm, that does not sound promising.
Ill make sure to bring a TA-10.1 as backup, just in case.
Hmm, didn't know there was a "new" version. I bought them last year (spring/summer 2010). It was a silver chassis and "550W"
Any special markings on the "new" version?
Yeah, the 550W sticker is gone, that the obvious difference. It now features protection relays, and better board layout, etc etc. It's a complete overhaul. Still not up there with the Trends, Muse and other higher cost ones but it's getting close.
It was introduced in February I think. That or March. It's called the 2011 updated new version.
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Here is one implementation of a boombox. The amplifier is my own design and it includes a push-pull SMPS + TDA8920BTH class-D amplifier chip. The PCB has four layers. The speakers are MGR 8" (cheapest with decent sensitivity ).
).An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Hi, we are building a boombox for the upcoming Roskilde Festival, it's our first time we've done it, and we have bought the following items
Lepai TA2020 Class-T Amp mini Stereo Amplifier 20WX2 - eBay.com.sg: Lepai TA2020 Class T Amp Mini Stereo Amplifier 20WX2 (item 180655852672 end time May 19, 2011 11:47:56 SGT)
6x9" 360W Xzound GTX-2 - 6x9" hjttalerst 360W Xzound GTX-2 - Hjttalere - HiFi, DVD og Multimedie - Autoudstyr - thansen.dk
Continuous Output power 160
Normal impedence 4 Ohm
Varta 12V carbattery 61AH
Would these parts fit great together, or?
Do you have some good advices for it, what should the volume be inside the box. Anything we should be aware of?
Thanks in advance
Lepai TA2020 Class-T Amp mini Stereo Amplifier 20WX2 - eBay.com.sg: Lepai TA2020 Class T Amp Mini Stereo Amplifier 20WX2 (item 180655852672 end time May 19, 2011 11:47:56 SGT)
6x9" 360W Xzound GTX-2 - 6x9" hjttalerst 360W Xzound GTX-2 - Hjttalere - HiFi, DVD og Multimedie - Autoudstyr - thansen.dk
Continuous Output power 160
Normal impedence 4 Ohm
Varta 12V carbattery 61AH
Would these parts fit great together, or?
Do you have some good advices for it, what should the volume be inside the box. Anything we should be aware of?
Thanks in advance
Hi, we are building a boombox for the upcoming Roskilde Festival, it's our first time we've done it, and we have bought the following items
Lepai TA2020 Class-T Amp mini Stereo Amplifier 20WX2 - eBay.com.sg: Lepai TA2020 Class T Amp Mini Stereo Amplifier 20WX2 (item 180655852672 end time May 19, 2011 11:47:56 SGT)
6x9" 360W Xzound GTX-2 - 6x9" hjttalerst 360W Xzound GTX-2 - Hjttalere - HiFi, DVD og Multimedie - Autoudstyr - thansen.dk
Continuous Output power 160
Normal impedence 4 Ohm
Varta 12V carbattery 61AH
Would these parts fit great together, or?
Do you have some good advices for it, what should the volume be inside the box. Anything we should be aware of?
Thanks in advance
First of all, read the whole thread because your question is asked like a thousand times in more or less the same way.
Im sorry to disappoint you but the speakers you choose and the battery conflict with the purpose of the boominator, and that is to play load on low energi usage while still having a fairly light boombox. First of all that battery is very heavy. Its altso not built to be discharged completely. Car batteries are made to have a high jolt and then charge back up. Its simply not designed for the purpose of a boombox. The problem with the speakers is that there is not any info to use for calculation of the volume of the box, or atleast i can not find any?
What kind of design are you aiming at, the boominator or just a box with a amp, battery and speakers?
The boominator is many hours of work done by Saturnes calculating the perfect design to maximize the performance and mobility of the boombox which is discussed in this thread. Making such a high quality product will be difficult with your materials.
"If you lower the impedance of the woofers by paralleling them you'll give your amplifier a smaller load and it can therefore perform better."
I just noticed this from a few posts back and wanted to make sure it got corrected. Just the opposite is true, in that a 4 ohm load actually places more demands on the amplifier, not less. Think of an electric drill--one that draws 6 amps will have a lot more power than one that draws three amps. And the one that draws more amps will do so because of Ohm's law: lower resistance. It's not the same thing as impedance, which brings frequency into the mix, but the notion is the same.
That's the reason a really low-ohm load overheats an amp not designed for it, because it's pushing more current through it and can't get rid of the heat beyond a certain point.
--Buckapound
I just noticed this from a few posts back and wanted to make sure it got corrected. Just the opposite is true, in that a 4 ohm load actually places more demands on the amplifier, not less. Think of an electric drill--one that draws 6 amps will have a lot more power than one that draws three amps. And the one that draws more amps will do so because of Ohm's law: lower resistance. It's not the same thing as impedance, which brings frequency into the mix, but the notion is the same.
That's the reason a really low-ohm load overheats an amp not designed for it, because it's pushing more current through it and can't get rid of the heat beyond a certain point.
--Buckapound
It was sorta what I was trying to explain in layman terms, as the amp6 does have a higher output at 4ohm than 8.. The explanation was perhaps a bit gauche, but for someone with little understanding of electronics, I think it explained it a bit..
Thanks Buckapound for clearing it up
Hi, we are building a boombox for the upcoming Roskilde Festival, it's our first time we've done it, and we have bought the following items
Lepai TA2020 Class-T Amp mini Stereo Amplifier 20WX2 - eBay.com.sg: Lepai TA2020 Class T Amp Mini Stereo Amplifier 20WX2 (item 180655852672 end time May 19, 2011 11:47:56 SGT)
6x9" 360W Xzound GTX-2 - 6x9" hjttalerst 360W Xzound GTX-2 - Hjttalere - HiFi, DVD og Multimedie - Autoudstyr - thansen.dk
Continuous Output power 160
Normal impedence 4 Ohm
Varta 12V carbattery 61AH
Would these parts fit great together, or?
Do you have some good advices for it, what should the volume be inside the box. Anything we should be aware of?
Thanks in advance
Gah, its a bit annoying that you post something like this in a thread about the Boominator which has 120+ pages advising NOT to ever use carparts in a boombox..
Its not possible to calculate what the volume of the cabinet should be nor the port as there are no specifications on those speakers.. You really need to read the entire thread and then return when you have a deeper understanding of Boombox-building