now, my follow up question is this:
how much power will they use in reality?
i have estimated my 1000wrms/2000w max amp for my tops to use about 125-250wrms in reality because of a -9db crest factor.
i want to have an idea of how many batteries are needed to power these
how much power will they use in reality?
i have estimated my 1000wrms/2000w max amp for my tops to use about 125-250wrms in reality because of a -9db crest factor.
i want to have an idea of how many batteries are needed to power these
The amount of power used will all depend on the crest factor of the music you play.
Your estimate for the top cabinets is reasonably conservative.
Some EDM low frequency peak-to-average power ratio is similar to a sine wave (3dB) which could be reduced even further by amp clipping, a square wave has a peak-to-average power ratio of 0dB.
If you are trying to estimate how many lead-acid batteries are needed, don't forget to include Peukert’s law..
Your estimate for the top cabinets is reasonably conservative.
Some EDM low frequency peak-to-average power ratio is similar to a sine wave (3dB) which could be reduced even further by amp clipping, a square wave has a peak-to-average power ratio of 0dB.
If you are trying to estimate how many lead-acid batteries are needed, don't forget to include Peukert’s law..
ah, Peukert’s law, didn't know about that one, i know voltage is dropping on high discharge rates though
interesting.. goddamn
that means i need heck of a battery bank. if my subs really would average 300wrms each, that is 100A in total... let's say my top is drawing 12A, we are up to 110A.
110A. at 0.2C that gives me a battery size of about 2000AH for 5 hours playtime if i understand this graph correctly? JEEESUS CHRIST. even at half that current i am up to 1000AH bank
interesting.. goddamn
that means i need heck of a battery bank. if my subs really would average 300wrms each, that is 100A in total... let's say my top is drawing 12A, we are up to 110A.
110A. at 0.2C that gives me a battery size of about 2000AH for 5 hours playtime if i understand this graph correctly? JEEESUS CHRIST. even at half that current i am up to 1000AH bank
Your "12v" car amp's output is probably based on around 13.8-14.2v.
Lower voltage will reduce the amp power considerably.
The amplifier might be at best around 90% efficient, so add 10% to all your calculations, and reduce power by the the expected voltage drop. And more amperage is required for the same watts as voltage drops...
With an average of 300 watts into a 15lb075, it will burn up fairly quickly 😉 .
That said, before it burns up, the voice coil temperature will rise, increasing it's impedance by as much as double, so it may loose 3dB in output compared to when it is cool.
At any rate, a 3dB increase in 1/w 1m sensitivity would half your battery requirements.
Doubling the amount of subs will increase sensitivity by 3dB...
When you consider the Peukert effect, lithium batteries can be a much better value, even before considering that their voltage does not drop under load like a lead acid's does.
The SPL of of a 2.2kw generator is nothing compared to the sound system you are proposing, but the cost of a battery bank that can sustain 2.2kW for five hours compared to diesel is.
Lower voltage will reduce the amp power considerably.
The amplifier might be at best around 90% efficient, so add 10% to all your calculations, and reduce power by the the expected voltage drop. And more amperage is required for the same watts as voltage drops...
With an average of 300 watts into a 15lb075, it will burn up fairly quickly 😉 .
That said, before it burns up, the voice coil temperature will rise, increasing it's impedance by as much as double, so it may loose 3dB in output compared to when it is cool.
At any rate, a 3dB increase in 1/w 1m sensitivity would half your battery requirements.
Doubling the amount of subs will increase sensitivity by 3dB...
When you consider the Peukert effect, lithium batteries can be a much better value, even before considering that their voltage does not drop under load like a lead acid's does.
The SPL of of a 2.2kw generator is nothing compared to the sound system you are proposing, but the cost of a battery bank that can sustain 2.2kW for five hours compared to diesel is.
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Dangit, i suppose i have to go grab that generator then…
Actually i found a used soundtown Nix 5000IB 230v amp for like 130 eur/usd. Maybe that could work, i could use 1 channel for subs and the other one for tops. That amp is actually cheap even compared do car audio amps
But that amp only has xlr Input? What more stuff do i need to get to get going? I’m not into pa stuff really… also the amp has no filtering…
Actually i found a used soundtown Nix 5000IB 230v amp for like 130 eur/usd. Maybe that could work, i could use 1 channel for subs and the other one for tops. That amp is actually cheap even compared do car audio amps
But that amp only has xlr Input? What more stuff do i need to get to get going? I’m not into pa stuff really… also the amp has no filtering…
For a tapped horn Design specifically for the 15lb075. Check this out:
http://www.hifi-forum.de/viewthread-159-10898.html
It is in German, but should be easily translatable.
Plans are Here:
https://workupload.com/file/wUxHuY4pYcx
And someone else who build it:
http://www.hifi-forum.de/index.php?action=browseT&forum_id=159&thread=10985&postID=5#5
http://www.hifi-forum.de/viewthread-159-10898.html
It is in German, but should be easily translatable.
Plans are Here:
https://workupload.com/file/wUxHuY4pYcx
And someone else who build it:
http://www.hifi-forum.de/index.php?action=browseT&forum_id=159&thread=10985&postID=5#5
thanks klaus, i will check it out!
now, how much midrange do i need to match 4 of these horns?
i am thinking about getting a whopping 32 of these cheap 6.5" car audio drivers: https://www.brl.se/sv/artiklar/madpm164.html
they are around like 10 euros a piece! still waiting for the quote from the firm though. apparently they should sound okay for the money
my other option is getting two more 12" midrange driver, since i already have two laying around, but that is not as cool as ditching them for a wall of 6.5" haha
now, how much midrange do i need to match 4 of these horns?
i am thinking about getting a whopping 32 of these cheap 6.5" car audio drivers: https://www.brl.se/sv/artiklar/madpm164.html
they are around like 10 euros a piece! still waiting for the quote from the firm though. apparently they should sound okay for the money
my other option is getting two more 12" midrange driver, since i already have two laying around, but that is not as cool as ditching them for a wall of 6.5" haha
Depending on the plans and drivers used, two 18" hog scoops may go lower, but won't be as loud as four jbell SS15.
Just get the most amount of driver area that you can afford. Worry about the design afterwards, size does not seem to be a concern.
At this point I would argue for high sensitivity drivers using the "port assisted" closed box, working the speaker JUST around its upper impedance peak. Say 18PS76 or more modern driver, tuning below the usable band (lets say 35Hz or whatever) and using the only 40-85Hz band. That should be quite efficient? Though from my angle of view, everything looks like nail when I'm a hammer. 🤭😂
hey welter,
why didn't you tell me about your keystone design? 😀
i'm now thinking two 18" keystones with two better b&c drivers, or two ROAR18. maybe that is better than cheaping out... would also leave me room to add another pair later on if i want
i struggle to find a frequency response on this box. you don't happen to have on for me? also, what ~300 euro driver would you go for?
why didn't you tell me about your keystone design? 😀
i'm now thinking two 18" keystones with two better b&c drivers, or two ROAR18. maybe that is better than cheaping out... would also leave me room to add another pair later on if i want
i struggle to find a frequency response on this box. you don't happen to have on for me? also, what ~300 euro driver would you go for?
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i found a pair of faitalpro 18hw1070 on the used market. i simulated these for the THAM18 and they performed poorly, but way better for ROAR18:
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Because you wrote "sound quality is not my priority" "looking for LOUD".
The Keystone with the B&C 18SW115-4 has good sound quality, goes lower than the designs you have been considering, but is not the "LOUDEST" nor has the best output per euro ratio.
To get the most out of a pair of B&C 18SW115-4/Keystone I'd recommend ~6000 watts, considerably more than the 1000-2000w range you have been writing about.
The response of the Keystone sub can be seen in the OP and all through the thread.
https://www.diyaudio.com/community/threads/keystone-sub-using-18-15-12-inch-speakers.185588/
The Keystone with a single B&C 18SW115-4 has similar sensitivity and frequency response to the 2x18" JBL SRX728, but considerably more output due to the B&C 18SW115-4 having ~+6dB more excursion potential.
I have no experience with the ROAR18, and don't know the pricing of drivers in the European market.
Art
Okay, i ditch that idea
I was told the 15lb075 only could take, at best 150w in a ss15 box because of the low xmax, and the 15lb100 could take at best 250-300w. So i thought maybe it would be better with two proper 18” boxes, playing a bit deeper is just a sweet bonus. I can maybe another one later
The roar15 has decent output i think?
I have a few options in my price range:
2 used faitalpro 18hw1070
2 new b&c 18tbx100
2 new b&c 18nbx100
2 new b&c 18nw100
2 new rcf lf18g401
These are about half the price of the 18sw115
By going with 2*18” i lose ~3db sensitivity compared to 4 ss15 boxes, but with the better drivers i would be able to feed them more power to make up for the loss
I could of course option for a single 18sw115 too, and put it in a c2e paraflex box or something, but i dont know if it would be worth it
I was told the 15lb075 only could take, at best 150w in a ss15 box because of the low xmax, and the 15lb100 could take at best 250-300w. So i thought maybe it would be better with two proper 18” boxes, playing a bit deeper is just a sweet bonus. I can maybe another one later
The roar15 has decent output i think?
I have a few options in my price range:
2 used faitalpro 18hw1070
2 new b&c 18tbx100
2 new b&c 18nbx100
2 new b&c 18nw100
2 new rcf lf18g401
These are about half the price of the 18sw115
By going with 2*18” i lose ~3db sensitivity compared to 4 ss15 boxes, but with the better drivers i would be able to feed them more power to make up for the loss
I could of course option for a single 18sw115 too, and put it in a c2e paraflex box or something, but i dont know if it would be worth it
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KaffiMann: Almost. It must go hand in hand with motor force or you just burn it all to heat. Amps are arguably more expensive than speakers. Always balance things out.
For synthetic music, I would argue against 3000W into one speaker with not so long 4.5 coil and stiffer suspension (18SW115 gets the pass). That might be expensive to buy, expensive to drive, and expensive to buy recones. 🤭
For synthetic music, I would argue against 3000W into one speaker with not so long 4.5 coil and stiffer suspension (18SW115 gets the pass). That might be expensive to buy, expensive to drive, and expensive to buy recones. 🤭
Agreed, though I guess that solves itself to some extent if the drivers have high-ish xmax.
Most weak motor designs have low-ish xmax.
So far it seems like the OP is going for around 200-300 Watts per driver, not overly concerned about cooling so far, but it is an important point.
Most weak motor designs have low-ish xmax.
So far it seems like the OP is going for around 200-300 Watts per driver, not overly concerned about cooling so far, but it is an important point.
For what it's worth, I drive the 15lb075 in my tapped horn with a 500W/4Ohm Thomann e-800, managed to let it smell, but never had excursion problems. It is limited to something like 0,7*max. Voltage and usually I low cut at 40Hz.