Hey guys,
I (electronical knownledge, but nothing about speakers) would love to create my own Boombox.
What I want:
Now I had the idea of an expendable Box (as in the picture shown) but possibly in a way, making length with and depth the same when it is extended. There is no need for Stereo sound or any specialties for Higher sound Quality, its just a simple Boombox 🙂
I need to find the right driver (max. 100€, 95+dB) to achieve this goal, and Tipps to find a good AMP for it. Aswell i apreciate help and tipps regarding my design.
http://imgur.com/McgZOjA
Red: silicon or sth
Green: Driver, obviously 😉
Yellow (or w/e): LiPo Battery
Blue: Amplifier
...Yea I know I forgot some wire and a battery loader :/
I hope you can help me.
Regards
Illousion
I (electronical knownledge, but nothing about speakers) would love to create my own Boombox.
What I want:
- 1 Fullrange driver (8"?)
- Class D AMP
- 5 - 10 Ah LiPo Battery
- Lowest possible room (should fit in a rucksack)
- Highest possible bass (should be able to fill a normal room; 15m²)
- Max efficiency
Now I had the idea of an expendable Box (as in the picture shown) but possibly in a way, making length with and depth the same when it is extended. There is no need for Stereo sound or any specialties for Higher sound Quality, its just a simple Boombox 🙂
I need to find the right driver (max. 100€, 95+dB) to achieve this goal, and Tipps to find a good AMP for it. Aswell i apreciate help and tipps regarding my design.
http://imgur.com/McgZOjA
Red: silicon or sth
Green: Driver, obviously 😉
Yellow (or w/e): LiPo Battery
Blue: Amplifier
...Yea I know I forgot some wire and a battery loader :/
I hope you can help me.
Regards
Illousion
Some comments:
8" driver, small box, highish efficiency, extended bass are counter to one another. Better to look at a smaller driver.
Given the constraints given my 1st suggestion would be Mark Audio Alpair 10p (pricing in Europe may push your budget, they are $110 each in USA). It really likes 16-17 litres, but probably works in as small as 10 litre. It is a 5 1/4" class driver.
The expandable box is a challenge, how do you keep it sealed, sealed over time, and keep it from being a secondary radiator.
For power amp, Class D is suggested, the TI 3116/3110s seem to be current favorites.
dave
8" driver, small box, highish efficiency, extended bass are counter to one another. Better to look at a smaller driver.
Given the constraints given my 1st suggestion would be Mark Audio Alpair 10p (pricing in Europe may push your budget, they are $110 each in USA). It really likes 16-17 litres, but probably works in as small as 10 litre. It is a 5 1/4" class driver.
The expandable box is a challenge, how do you keep it sealed, sealed over time, and keep it from being a secondary radiator.
For power amp, Class D is suggested, the TI 3116/3110s seem to be current favorites.
dave
So I should go for smaller drivers?
After I had seen the woofers to some pc speakers I thought that you can fit some bigger drivers in a small box aswell..
Regarding Specially this driver I hope there are better alternatives since it is expensive but misses some efficiency..
Can I reach with drivers around 5" enough bass? I really don't know much about speakers, but I know bigger drivers you mostly will get better bass 😱
And what playable frequency should I aim for? 80hz?
I hope you guys can clear my mind 🙂
After I had seen the woofers to some pc speakers I thought that you can fit some bigger drivers in a small box aswell..
Regarding Specially this driver I hope there are better alternatives since it is expensive but misses some efficiency..
Can I reach with drivers around 5" enough bass? I really don't know much about speakers, but I know bigger drivers you mostly will get better bass 😱
And what playable frequency should I aim for? 80hz?
I hope you guys can clear my mind 🙂
Not 8". A biggish driver in a small box that goes low means you need lots of power.
There are 3" drivers that will get you that low, but with limited loudness capability.
Probably the 1st thing to figure out is a target volume. How big a box can you put into your rucksack?
dave
Well, ofc I want to get away with smallest possible box, but better a little bigger than not enough sound..
If you for example take a look at the 2.1 systems of logitech, like the Z-213 for example, i would be pretty happy if i could achieve that volume level.
With the design i planned i could nearly double the effective room inside the speaker, if its extended.
For my rucksack the possible size would be around 25x35x15 cm or maybe a little bigger. So i could reach possibly 25x35x25 if it is extended, this would let it have a volumen of 21 7/8 liters.
Thanks for your friendly help by the way 🙂
If you for example take a look at the 2.1 systems of logitech, like the Z-213 for example, i would be pretty happy if i could achieve that volume level.
With the design i planned i could nearly double the effective room inside the speaker, if its extended.
For my rucksack the possible size would be around 25x35x15 cm or maybe a little bigger. So i could reach possibly 25x35x25 if it is extended, this would let it have a volumen of 21 7/8 liters.
Thanks for your friendly help by the way 🙂
That sure lowers the bar from what i gathered from your 1st post.
These are designed for near-field use. They have a 2" FR crossed over to a woofer that likely makes it to about 50 Hz. Small cheap amps limit the output. XO to the woofer is likely either too high or there is a hole in the response.
Any number of good 4" FRs should better these. The A10p should be significantly better in all respects.
Assuming 12mm plywood, that gives a gross internal volume of 9.2 litres without an expandable chamber -- that might give you half as much again. With space taken up by battery, amp etc you probably have about 5-7 litre to work with. That indicates a ~4" driver.
Mark Audio CHP70/CHR70/Alpair 6x or 7x, Fostex FF105/125wk, there are a raft of TandBands and others.
I'd likely put Alpair 6p or FF105wk at the top of the list, but CHP70.2 or Alpair 7p would play louder and go lower.
dave
Let us say, the more bass the better, I love to listen to electronic music like dubstep, trap, big room, etc. I won't take the boombox to a barbecue to listen to Beethoven 😉
I don't require special sound quality, but more bass sound and efficiency. Therefore, I want to spend max 100€ on the drivers, since they don't need to be that special regarding sound quality. I have good speakers and good headphones @home that's not what I need 🙂
For design issues I think I want to aim for a cubic form so we could go for having 25^3 or maybe maybe 30 ^3 if it is extended.
Regarding the drivers you have shown I don't like their efficiency, is there no possibility to get over 90dB/W(m)?
I just wish to get a good robust boombox to play in longer nights at barbecues or houseparties of ppl (which are retarded enough not to have useful speakers). I hope I could explain what I want in a way you know my needs 🙂
And I really appreciate your help, since I'm completely retarded with my knowledge about speakers and feel like stumbling in the dark 😀
I don't require special sound quality, but more bass sound and efficiency. Therefore, I want to spend max 100€ on the drivers, since they don't need to be that special regarding sound quality. I have good speakers and good headphones @home that's not what I need 🙂
For design issues I think I want to aim for a cubic form so we could go for having 25^3 or maybe maybe 30 ^3 if it is extended.
Regarding the drivers you have shown I don't like their efficiency, is there no possibility to get over 90dB/W(m)?
I just wish to get a good robust boombox to play in longer nights at barbecues or houseparties of ppl (which are retarded enough not to have useful speakers). I hope I could explain what I want in a way you know my needs 🙂
And I really appreciate your help, since I'm completely retarded with my knowledge about speakers and feel like stumbling in the dark 😀
Just saw this Driver: FULL RANGE 12GA50 | Beyma
It is hella big but they recommend 20+ liters for it, do you have anything to say about it?
It is hella big but they recommend 20+ liters for it, do you have anything to say about it?
For your intended use, I'd recommend Visaton BG17. It's a cheap 6,5" driver, quite popular in Finland along with BG20 (especially in boomboxes). Make a bass reflex box with around 80Hz tuning. For outdoors use, it will likely sound good.
I didn't model it, but with that high Q, and high Fs, it will have a big bump before it rolls off and will likely be challenged to hit 100 Hz.
It should play loud with little power thou. The shelved up topendmay make it sound a bit tinny.
dave
1. Fullrange driver (8"?)
2. Class D AMP
3. 10 Ah LiPo Battery
4. Lowest possible room (should fit in a rucksack)
5. Highest possible bass (should be able to fill a normal room; 15m²)
6. Max efficiency
---
1. and 6. Faital Pro 4FE32 8ohms x qnty 4 drivers for a bipole. Wired in parallel you will get ~95 to 97 dB at 2.83v and 4ohms load. Bipole with drivers front and back will give you 360 deg sound and improve bass because you won't have baffle step loss of bass.
2 Get TPA3116D2 amp - get the $15 board from Aliexpress - best value/sound with no mods. Online Shop Free Shipping! 1pc TPA3116 Class D digital amplifier 50W +50 W with Silent Sleep Design|Aliexpress Mobile capable of 40 watts clean power (0.1% THD at 40 watts and 4ohms with 24v supply)
3. Battery - your choice but may need to add enough cells to get 24v if you want max power. 12v can work well too at moderate SPL.
4. Smallest possible volume would be the XKi 6th order bandpass Karlson aperture alignment but that may be more complicated than you want. Just go with bass reflex with dual drivers tuned for 60Hz. The lower Qts and Vas of the 4FE32 will let you get smaller volumes. Even smaller is to put all drivers in one common chamber and use a single larger passive radiator - this is how many of the smaller Bluetooth micro boomboxes do it.
5. Highest possible bass - what is your SPL requirement? Qnty 4 x 4 in drivers in a ported box or with a passive radiator should get you pretty good bass. The XKi box would get you the highest SPL bass as it controls cone excursion for more power.
2. Class D AMP
3. 10 Ah LiPo Battery
4. Lowest possible room (should fit in a rucksack)
5. Highest possible bass (should be able to fill a normal room; 15m²)
6. Max efficiency
---
1. and 6. Faital Pro 4FE32 8ohms x qnty 4 drivers for a bipole. Wired in parallel you will get ~95 to 97 dB at 2.83v and 4ohms load. Bipole with drivers front and back will give you 360 deg sound and improve bass because you won't have baffle step loss of bass.
2 Get TPA3116D2 amp - get the $15 board from Aliexpress - best value/sound with no mods. Online Shop Free Shipping! 1pc TPA3116 Class D digital amplifier 50W +50 W with Silent Sleep Design|Aliexpress Mobile capable of 40 watts clean power (0.1% THD at 40 watts and 4ohms with 24v supply)
3. Battery - your choice but may need to add enough cells to get 24v if you want max power. 12v can work well too at moderate SPL.
4. Smallest possible volume would be the XKi 6th order bandpass Karlson aperture alignment but that may be more complicated than you want. Just go with bass reflex with dual drivers tuned for 60Hz. The lower Qts and Vas of the 4FE32 will let you get smaller volumes. Even smaller is to put all drivers in one common chamber and use a single larger passive radiator - this is how many of the smaller Bluetooth micro boomboxes do it.
5. Highest possible bass - what is your SPL requirement? Qnty 4 x 4 in drivers in a ported box or with a passive radiator should get you pretty good bass. The XKi box would get you the highest SPL bass as it controls cone excursion for more power.
Hm.. i guess i will go for the Visaton BG17 which Mayuri recommended (thanks man). It is pretty cheap, has a good efficiency and I find no reasons to buy a driver which is more expensive.
What about the design? bassreflex? passive radiators? (horns need too much volume, right?)
What about the design? bassreflex? passive radiators? (horns need too much volume, right?)
High Q driver, you want as large an aperiodic box as you can live with.Don't expect very low bass.
dave
@Xrk971 could you tell me, what do I need to know about those passive radiators?
I would try not to get over 15W with the power consumption, since i want to use this lipo batterie: Modellbau-Akkupack QUATPOWER LA4250-35-6S, LiPo, 22,2 V-/4250 mAh - Stromversorgung - Akkus - LiPo-Akkus - Pollin Electronic
It has 4.25Ah and 22.2V so I will have 94.35 Wh (94.35Wh/15W = 6.29h while listening to maximum loudness)
if i would build a box with 25³ from Plywood (maybe get it that thick to let is resonate with the bass?) and would fit 4 times the same full range driver into it (one on each side) and a passive radiator on the top, which drivers are best for that and how do i select the fitting passive radiator?
The box would probably have ~13liters and if I put the battery etc. in i think i can go with 10 liters.
Again thanks for your help 🙂
I would try not to get over 15W with the power consumption, since i want to use this lipo batterie: Modellbau-Akkupack QUATPOWER LA4250-35-6S, LiPo, 22,2 V-/4250 mAh - Stromversorgung - Akkus - LiPo-Akkus - Pollin Electronic
It has 4.25Ah and 22.2V so I will have 94.35 Wh (94.35Wh/15W = 6.29h while listening to maximum loudness)
if i would build a box with 25³ from Plywood (maybe get it that thick to let is resonate with the bass?) and would fit 4 times the same full range driver into it (one on each side) and a passive radiator on the top, which drivers are best for that and how do i select the fitting passive radiator?
The box would probably have ~13liters and if I put the battery etc. in i think i can go with 10 liters.
Again thanks for your help 🙂
Look for a passive radiator with about double the Sd of your total cone Sd. The 4FE32 is 50cm2 ea x 4 is 200cm2 x 2 is 400cm2. That is about same as an 8in passive radiator. That may make yor box big unless you have a special rectangular one. To model it you need to use something like akabak - which is not easy to use. I don't know of WinISD handles PR's.
Alternatively a pair of 5in PR's is same area as 8in.
Alternatively a pair of 5in PR's is same area as 8in.
8" would fit into when i go 25x25x25cm.
Is it the best choice if i go for the 4FE32 together with this radiator for example: Dayton Audio SD215-PR 8" Passive Radiator
?
And fit all of that into a 25³ Plywood box?
And can i use a resonating thickness of the box?
And what if I would go smaller building only a 20³ box? :/
I totally don't know what do do with this boombox.
To fit it into my rucksack it may maximal have this sizes:
height: 40cm
width: 20cm
length: 25cm
To make it comfortable it may have 20x20x30.
How can i get the maximum bass out of it?
Im getting depressed with this ._.
Is it the best choice if i go for the 4FE32 together with this radiator for example: Dayton Audio SD215-PR 8" Passive Radiator
?
And fit all of that into a 25³ Plywood box?
And can i use a resonating thickness of the box?
And what if I would go smaller building only a 20³ box? :/
I totally don't know what do do with this boombox.
To fit it into my rucksack it may maximal have this sizes:
height: 40cm
width: 20cm
length: 25cm
To make it comfortable it may have 20x20x30.
How can i get the maximum bass out of it?
Im getting depressed with this ._.
Last edited:
A PR is a port substitute in a BR. Neither the Visaton or Beyma are suitable for BR.
Attached is the sim of BG 17 in 10 litre sealed. F6 about 105, F10 88. This is not as low as the FF85wk in an oprimum reflex and it is considered to have no real bass.
A bit of extention and a bit less of a hump could be had with aperiodic loading, but the hump is not as bad as i guessed. Itmay be enuff to give the illusion of bass.
Trying to make it BR would make it worse, so no PRs no ports.
dave
Attached is the sim of BG 17 in 10 litre sealed. F6 about 105, F10 88. This is not as low as the FF85wk in an oprimum reflex and it is considered to have no real bass.
A bit of extention and a bit less of a hump could be had with aperiodic loading, but the hump is not as bad as i guessed. Itmay be enuff to give the illusion of bass.
Trying to make it BR would make it worse, so no PRs no ports.
dave
Attachments
The PR you linked should work with the qnty 4 x 4FE32's. Need to model it though because the PR allows you to have a smaller volume than if you were to use a port.
Sure, then you need a 2-way system with XO and now tweeters. Although you can use full range drivers like the 3FE25 or Vifa TC9FD as a fullrange tweeter from 300Hz to 20kHz, and a woofer from 50Hz to 300Hz. This is the so-called FAST (fullrange assisted subwoofer technology) approach and can work very well. More info in other FAST threads. If you want conventional woofer tweeter XO at circa 1kHz to 3kHz approach, you will have to ask for help in the multiway forum where this question has been asked/and answered at least a thousand times already.
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