Hi, i did just register on this forum, but i've been reading threads around here for a couple of weeks.
I'm planning on making a boombox in the style of a Thodio iBox. I know that there has been many threads about the subject but the amount of hardware analysis hasn't really been done.
If you watch this video:
thodio iBox XC audiophile iPod speaker Boombox aptX? Bluetooth - YouTube
The iBox seems to punch a good amount of volume due to it's small size and weight. (9kg or 20lbs)
So what do we know ?
The manufacturer claims that they use a audiophile tripath TK2050 based 2 x 100 watts RMS amplifier.
In my build i would throw that amplifier in the garbage can straight away due to it's high battery consumption compared to a Tripath TA2020 chip based amp like the "41hz AMP6 Basic kit". (I ordered that amp kit last week btw)
Then we got the battery and the speakers.
What do u guys think that would be a fair solution to speakers and battery ?
My demands are low weight and decent volume.
My current boombox is made of 12mm plywood and uses a 12v amp from china (not sure about chipset)
with a 4Ah lead acid battery, the weight is 6kg, and it got 2pcs "Clarion coaxial 5.25" speakers.
I know you boombox veterans will be laughing at my previous build, but i wasn't really in to this back then. Now i have read a whole lot of build, including over half of the legendary Boominator thread by Saturnus.
And guys, i live in Finland so i most likely wont order anything expensive from outside EU due to the VAT and high price shipping.
So feel free to post links and stuff, i really want to make a new kind of "default" boombox design like the Boominator but in a much smaller and lightweight package.
I know you can't brake the laws of physics considering weight and volume do relate to each other in these kind of projects.
But i'm pretty sure we guys can get really close to braking the laws if we all put our competence and experience together.
I don't know if this is the right forum to post but mods feel free to moce the thread if you like.
I'm planning on making a boombox in the style of a Thodio iBox. I know that there has been many threads about the subject but the amount of hardware analysis hasn't really been done.
If you watch this video:
thodio iBox XC audiophile iPod speaker Boombox aptX? Bluetooth - YouTube
The iBox seems to punch a good amount of volume due to it's small size and weight. (9kg or 20lbs)
So what do we know ?
The manufacturer claims that they use a audiophile tripath TK2050 based 2 x 100 watts RMS amplifier.
In my build i would throw that amplifier in the garbage can straight away due to it's high battery consumption compared to a Tripath TA2020 chip based amp like the "41hz AMP6 Basic kit". (I ordered that amp kit last week btw)
Then we got the battery and the speakers.
What do u guys think that would be a fair solution to speakers and battery ?
My demands are low weight and decent volume.
My current boombox is made of 12mm plywood and uses a 12v amp from china (not sure about chipset)
with a 4Ah lead acid battery, the weight is 6kg, and it got 2pcs "Clarion coaxial 5.25" speakers.
I know you boombox veterans will be laughing at my previous build, but i wasn't really in to this back then. Now i have read a whole lot of build, including over half of the legendary Boominator thread by Saturnus.
And guys, i live in Finland so i most likely wont order anything expensive from outside EU due to the VAT and high price shipping.
So feel free to post links and stuff, i really want to make a new kind of "default" boombox design like the Boominator but in a much smaller and lightweight package.
I know you can't brake the laws of physics considering weight and volume do relate to each other in these kind of projects.
But i'm pretty sure we guys can get really close to braking the laws if we all put our competence and experience together.
I don't know if this is the right forum to post but mods feel free to moce the thread if you like.
I'm designing my next boom box using PVC pipes
but in the amp stage i'm stuck, the TA2020 can give just 10w with aceptable distortion, but the one Thodio uses is a total overkill, for the first part i will try TDA2040, just to se if the box have a good sound and everything is ok
For the battery i will be using 6 18650 Li-Ion cells, light weight and have a good capacity i think that's good solution, if you need more juice just add more cells
but in the amp stage i'm stuck, the TA2020 can give just 10w with aceptable distortion, but the one Thodio uses is a total overkill, for the first part i will try TDA2040, just to se if the box have a good sound and everything is ok
For the battery i will be using 6 18650 Li-Ion cells, light weight and have a good capacity i think that's good solution, if you need more juice just add more cells
Hmm, interesting idea you got there ..
I still think that the Amp6 could pump that volume lvl than other TA2020 chip based amps like the "Lepai LP-2020A+". The only downside with particularly the Amp6 is the maximum 14.5VDC restriction, but do you guys know if that limit is spot on ?
What will for instance happen if i feed 14,8V DC into the Amp6 (from 4pcs 18650 Li-Ion cells)
I still think that the Amp6 could pump that volume lvl than other TA2020 chip based amps like the "Lepai LP-2020A+". The only downside with particularly the Amp6 is the maximum 14.5VDC restriction, but do you guys know if that limit is spot on ?
What will for instance happen if i feed 14,8V DC into the Amp6 (from 4pcs 18650 Li-Ion cells)
It will die. A 4-cell li-ion pack is 16.8V when fully charged. Although the amp6 probably can survive 14.8V short term, there's no way it will survive 16.8V.
Well, is there any easy way to regulate the voltage to 14.5v or below ? Or is it easier to go with a amplifier with a wider voltage range .
If you're willing to accept the losses there's always dc-dc converters or just old fashioned regulators.
I don't see a need though.
Substitute the dangerous li-ion batteries (which are proven to self combust with 100% certainty) for safe LiFePO4 batteries and the problem is solved. LFPs are 3.2V nominal per cell, not 3.7V. Charge voltage is 3.6V per cell, not 4.2V. So a 4 cell LFP is 14.4V max, and maintains above 12.4V for 90% of it's cycle life.
But using 3 cells Li-Ion you get 12.6 fully charged and 11.1 almost discharged, you could use that to power the amp6
And yet we could play with the drivers, 2 8ohms driver in parallel you have 4 ohm and 6db more in sensitivity
And yet we could play with the drivers, 2 8ohms driver in parallel you have 4 ohm and 6db more in sensitivity
you know it will go up in flames at some point.
Seriously. Forget li-ion batteries for anything you build yourself. When they go up in flames (and they will) you can't even blame the manufacturer or get anything from the insurance.
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I have to disagree,
Today's Li-Ion cell have multiple levels of protection, a pcb that cut's over voltage, under voltage, over current, short circuit, disable the cell if it's to discharged. A physical valve that prevents the pressure build-up inside the cell
I use the 18650 cell's in flashlight's, everyday on my diy cellphone portable chargers, to power up amp's sometimes, never had problems
I had done in little research about LiFePo, the main problem i see is the low capacity per size, in the 18650 i get 2600ma, a same size LiFePo cell only 1000ma
Okay, so i suggest that LiFePo4 is the battery to go for a lightweight boombox build like this.
How much Ah do you guys think that it will be needed for this kind of project ?, lets think, that small boombox is mostly four one evening use, so let's say we want it to play for 15 hours. I know it's a lot more than just one evening, but let's always be on the safe side.
Let's say that we are listening to music and we are using a total of 10watts from the amplifier at 14.4V.
Ampere is now watts/volts (10/14.4) = 0.69 amps
Ah needed = Hours we want/Ampere (right)? = 15/0.69 = 21,7 Ah battery needed ?
My calculations are really really wrong or my values on the output wattage are not right.
Because we wont need a 22Ah battery to power that boombox for 15 hours do we ?
But okay, the second problem is that if we really need that much Ah from LiFePo4 batteries then isn't it going to cost alot ? I'm not sure what brand i've been looking on but what I have seen i can tell that LFP batteries seems to be really really expensive.
Can you guys link some side that have a EU webshop or Warehouse that sells LFP batteries for a reasonable price ? (if there is any)
How much Ah do you guys think that it will be needed for this kind of project ?, lets think, that small boombox is mostly four one evening use, so let's say we want it to play for 15 hours. I know it's a lot more than just one evening, but let's always be on the safe side.
Let's say that we are listening to music and we are using a total of 10watts from the amplifier at 14.4V.
Ampere is now watts/volts (10/14.4) = 0.69 amps
Ah needed = Hours we want/Ampere (right)? = 15/0.69 = 21,7 Ah battery needed ?
My calculations are really really wrong or my values on the output wattage are not right.
Because we wont need a 22Ah battery to power that boombox for 15 hours do we ?
But okay, the second problem is that if we really need that much Ah from LiFePo4 batteries then isn't it going to cost alot ? I'm not sure what brand i've been looking on but what I have seen i can tell that LFP batteries seems to be really really expensive.
Can you guys link some side that have a EU webshop or Warehouse that sells LFP batteries for a reasonable price ? (if there is any)
Science disagrees with you. It has been proven that all li-ion cells without exception and no matter the protection and care taken always will self-combust. It may take 1000s of years, or it may take a week but they will self-combust at some point.
Lainus, music signals are not continuous sinus waves. So divide power by 8 but remember to double for 2 channels.
As mentioned several times in the Boominator thread, a 7Ah SLA lasts about 20 hours at maximum volume before clipping. So a 6600mAh LiFePO4 should be plenty. Luckily that's also pretty easy to get and although costly to buy (roughly $100 for roughly 7Ah is standard) it is in fact cheaper than li-ion batteries simply because they can be recharged at least 10 times more before capacity starts to drop (2000-5000 deep cycles vs. 200-500 deep cycles). Even if an LiFePO4 is overcharged/overdischarged by accident, all that happens is a loss of a few hundred effective deep cycles.
I am not aware of any EU dealer that have them in stock, luckily LiFePO4 batteries are by default UN38.3 approved so they can be shipped internationally.
This is an example of what can be found on aliexpress. These are same size as 12V 7Ah standard SLAs.
Free shipping 1pcs/lot LiFePO4 Battery 12V 7.5Ah for UPS or E bike with Long cycle life or motorcycle starter-in Battery Packs from Electrical Equipment & Supplies on Aliexpress.com
Many other options are available. If you like to DIY your own pack you can typically get away with 2/3rd of that price even when the PCM is included.
As mentioned several times in the Boominator thread, a 7Ah SLA lasts about 20 hours at maximum volume before clipping. So a 6600mAh LiFePO4 should be plenty. Luckily that's also pretty easy to get and although costly to buy (roughly $100 for roughly 7Ah is standard) it is in fact cheaper than li-ion batteries simply because they can be recharged at least 10 times more before capacity starts to drop (2000-5000 deep cycles vs. 200-500 deep cycles). Even if an LiFePO4 is overcharged/overdischarged by accident, all that happens is a loss of a few hundred effective deep cycles.
I am not aware of any EU dealer that have them in stock, luckily LiFePO4 batteries are by default UN38.3 approved so they can be shipped internationally.
This is an example of what can be found on aliexpress. These are same size as 12V 7Ah standard SLAs.
Free shipping 1pcs/lot LiFePO4 Battery 12V 7.5Ah for UPS or E bike with Long cycle life or motorcycle starter-in Battery Packs from Electrical Equipment & Supplies on Aliexpress.com
Many other options are available. If you like to DIY your own pack you can typically get away with 2/3rd of that price even when the PCM is included.
In that point i agree, since lithium react with the atmosphere gases, but i still prefere to use them, the price, and the relation of volume/capacity
Of course if missused they offer great danger, but since they are used a lot in today's world (cars,cell phones, computers, etc) i'm not too worried about safety issues
But the weight isn't too critical and have funds to spend i agree with the LiFePo, in my project i have little space to the baterries, so Li-ion is the way
I don't share the same paranoia of lithium ion cells, provided cells are properly selected and taken care of. This includes:
- Keep them within a good temperature range (10-40 deg C - cell temperature, not ambient)
- Don't overcharge. I charge 4.2V lithium ion batteries to 4.0-4.1V.
- Don't overdischarge.
- Use fuses.
- Use charge balancing with multiple series cells.
- Use cylindrical cells, not bag cells. They're made by machine, a lot more consistent and a lot more durable.
Lithium thionyl chloride cells, on the other hand, scare the **** out of me.
- Keep them within a good temperature range (10-40 deg C - cell temperature, not ambient)
- Don't overcharge. I charge 4.2V lithium ion batteries to 4.0-4.1V.
- Don't overdischarge.
- Use fuses.
- Use charge balancing with multiple series cells.
- Use cylindrical cells, not bag cells. They're made by machine, a lot more consistent and a lot more durable.
Lithium thionyl chloride cells, on the other hand, scare the **** out of me.
Okay guys, now i'm considering a 7ah SLA battery again because it's easy to get and really cheap. I most likely will upgrade it in the future but for now it has to do.
So what about the speakers, is there anyway possible that i can get as much volume from a amp6 combined with the right speakers (some 4ohm high sense speakers i suppose) ?
What would the speakers be ?
i can't find any documentation on what speakers is used in the iBox, however maybe some fullrange 4ohm PA speakers that is affordable would do ?
When i know what speakers i'm going to use i will start to make a 3D sketch in Solidworks. But i need to know what the volume of the box is going to be first.
Please keep coming with replies, suggestions and thoughts, it's really nice how active you guys are at answering on this forum.
So what about the speakers, is there anyway possible that i can get as much volume from a amp6 combined with the right speakers (some 4ohm high sense speakers i suppose) ?
What would the speakers be ?
i can't find any documentation on what speakers is used in the iBox, however maybe some fullrange 4ohm PA speakers that is affordable would do ?
When i know what speakers i'm going to use i will start to make a 3D sketch in Solidworks. But i need to know what the volume of the box is going to be first.
Please keep coming with replies, suggestions and thoughts, it's really nice how active you guys are at answering on this forum.
Hello guys, i'm gonna bump this thread after a few weeks of silence. I've got my amp6-basic and it's done and working. I also milled a custom heath´sink out of aluminium at work 😛
Now i'm going to start ordering speakers and stuff. I'm thinking of going 2pcs Monacor SP60/4 because they are so well known and V-Bro @41hz forums just completely loves them, and well, they are not expensive at all so why not give them a try. I'm thinking of matching them up with 2pcs of the Dayton ND16FA-6.
Saturnus recommended to use a 6.8uF capacitor as a HP-Filter for the Dayton tweeter, so i'm guessing i'm gonna trust him and go with the 6.8uF cap, that will give me a HP-Filter starting from about 3.9kHz.
So here's my current shopping cart at EU Audio:
2pcs Monacor sp-60/4 ND16FA-6 - Dayton 5/8 inch Neodymium Dome Tweeter - Europe Audio
2pcs Dayton ND16FA-6 SP-60/4 - Monacor HiFi bass-midrange speakers 60Wmax 4Ω - Europe Audio
2pcs EGL/6.8/50/5 - True bipolar smooth-foil capacitor 6.8uF 50V - Europe Audio (I'm not sure what caps to use since i can't really tell the difference between them)
So what do you guys think about the hardware so far?
Feel free to help with the caps and anything else, it's a open thread, every idea possible is great and encouraging 🙂
An externally hosted image should be here but it was not working when we last tested it.
Now i'm going to start ordering speakers and stuff. I'm thinking of going 2pcs Monacor SP60/4 because they are so well known and V-Bro @41hz forums just completely loves them, and well, they are not expensive at all so why not give them a try. I'm thinking of matching them up with 2pcs of the Dayton ND16FA-6.
Saturnus recommended to use a 6.8uF capacitor as a HP-Filter for the Dayton tweeter, so i'm guessing i'm gonna trust him and go with the 6.8uF cap, that will give me a HP-Filter starting from about 3.9kHz.
So here's my current shopping cart at EU Audio:
2pcs Monacor sp-60/4 ND16FA-6 - Dayton 5/8 inch Neodymium Dome Tweeter - Europe Audio
2pcs Dayton ND16FA-6 SP-60/4 - Monacor HiFi bass-midrange speakers 60Wmax 4Ω - Europe Audio
2pcs EGL/6.8/50/5 - True bipolar smooth-foil capacitor 6.8uF 50V - Europe Audio (I'm not sure what caps to use since i can't really tell the difference between them)
So what do you guys think about the hardware so far?
Feel free to help with the caps and anything else, it's a open thread, every idea possible is great and encouraging 🙂
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An externally hosted image should be here but it was not working when we last tested it.
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