Hi,
Sorry if this is in the wrong forum-category, could not really find the appropriate one.
Recently, I was gifted an amplifier and a battery board.
The amplifier board:
Looking for an Arylic Up2Stream Amplifier? - SoundImports
The battery board:
Looking for a LBB-5S Lithium Battery Board? - SoundImports
I want to use these to build a portable speaker for my football team.
As I'm quite the novice (been researching into speaker building for months but still feel like I don't have the faintest idea of what I'm doing), I could really use some advice on my choice of speakers for this build.
I want to keep it as simple as possible, luckily the amplifier has a crossover built-in so I want to just buy 2 full-range speakers for the 2 (50w) channels and a subwoofer for the 1 (100w) channel.
The user manual for the amplifier states this about the speaker power output:
2x50W@4Ω + 100W@2Ω BTL load at 24V
2x30W@8Ω + 75W@4Ω BTL load at 24V
2x22W@8Ω + 48W@4Ω BTL load at 19V
2x15W@8Ω + 30W@4Ω m BLT load at 15V
As I have (5) 18650 batteries at 6.7A and the battery board output states 21V, I think I'm correct to presume the maximum output would be 140W total and this would at max be outputting 2x35W@4Ω + 70W@2Ω?
After watching tens or hundreds of youtube videos, I still do not know which wattage speakers I should be searching for.
I've seen reviews for this board where someone just connects 15 watt speakers with a 20 watt subwoofer, sometimes a 300 watt subwoofer, and everything in between.
My problem is, as this is for a football team, I need speakers which can handle running at 100% volume. I'll try to avoid that, but I'm sure someone will always crank up the volume when I'm not watching.
What would be a good choice?
- What wattage and ohms for the 2 channels?
- What wattage and ohms for the 1 channel? (2 ohms is not an option so at least 4 ohms)
As I said before, this is for a football team so it needs to go very loud, so I'll have to check the efficiency and what not, but the 2 questions above are the ones I'm struggling with the most.
Sorry for the long post, and thanks in advance for everyone who takes the time to read my question.
Sorry if this is in the wrong forum-category, could not really find the appropriate one.
Recently, I was gifted an amplifier and a battery board.
The amplifier board:
Looking for an Arylic Up2Stream Amplifier? - SoundImports
The battery board:
Looking for a LBB-5S Lithium Battery Board? - SoundImports
I want to use these to build a portable speaker for my football team.
As I'm quite the novice (been researching into speaker building for months but still feel like I don't have the faintest idea of what I'm doing), I could really use some advice on my choice of speakers for this build.
I want to keep it as simple as possible, luckily the amplifier has a crossover built-in so I want to just buy 2 full-range speakers for the 2 (50w) channels and a subwoofer for the 1 (100w) channel.
The user manual for the amplifier states this about the speaker power output:
2x50W@4Ω + 100W@2Ω BTL load at 24V
2x30W@8Ω + 75W@4Ω BTL load at 24V
2x22W@8Ω + 48W@4Ω BTL load at 19V
2x15W@8Ω + 30W@4Ω m BLT load at 15V
As I have (5) 18650 batteries at 6.7A and the battery board output states 21V, I think I'm correct to presume the maximum output would be 140W total and this would at max be outputting 2x35W@4Ω + 70W@2Ω?
After watching tens or hundreds of youtube videos, I still do not know which wattage speakers I should be searching for.
I've seen reviews for this board where someone just connects 15 watt speakers with a 20 watt subwoofer, sometimes a 300 watt subwoofer, and everything in between.
My problem is, as this is for a football team, I need speakers which can handle running at 100% volume. I'll try to avoid that, but I'm sure someone will always crank up the volume when I'm not watching.
What would be a good choice?
- What wattage and ohms for the 2 channels?
- What wattage and ohms for the 1 channel? (2 ohms is not an option so at least 4 ohms)
As I said before, this is for a football team so it needs to go very loud, so I'll have to check the efficiency and what not, but the 2 questions above are the ones I'm struggling with the most.
Sorry for the long post, and thanks in advance for everyone who takes the time to read my question.
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One missing consideration is energy. The 18650 batteries are 6.7A, that would be A-H; they'd give you your 21V - at 100% volume - for an hour (ideally). Good enough for the application?
As music is different than a continuous tone, it's hard to imagine how "100% volume" translates into energy draw. Perhaps it's not that different with highly compressed stuff. Point being, you didnt mention the type of music being played - is this a substitute for the "pep band" that typically plays at football games?
I'm trying to imagine anything less than a 300 lb pair of Altec A7 VOT cabinets / horns out along a football field as being effective. Hardly a portable system as battery power suggests. I wouldnt worry about speaker wattage, rather worry about size - go for the largest speakers possible - and the power handling will take care of itself.
Such speakers produce (supposedly) in excess of 100 db SPL 4' in front with just 1W of power; > 120 db with 30W. That would be heard by the team, 20 - 30 yards out from the edge of the field...
Not that Altec A7s are realistic either in terms of availability or practicality. I just mention them so illustratively you'll get an idea of what it would take to well accomplish your goal. You wont get that from one of those slanted auto boxes with two 12s and a couple of piezo tweeters. You'll need high efficiency and that usually means large. Horns with compression drivers and big, efficient bass drivers.
Altec Lansing Voice of the Theatre (VOTT) - Great Plains Audio - look at the picture. Can you build something like the A8? ;')
As music is different than a continuous tone, it's hard to imagine how "100% volume" translates into energy draw. Perhaps it's not that different with highly compressed stuff. Point being, you didnt mention the type of music being played - is this a substitute for the "pep band" that typically plays at football games?
I'm trying to imagine anything less than a 300 lb pair of Altec A7 VOT cabinets / horns out along a football field as being effective. Hardly a portable system as battery power suggests. I wouldnt worry about speaker wattage, rather worry about size - go for the largest speakers possible - and the power handling will take care of itself.
Such speakers produce (supposedly) in excess of 100 db SPL 4' in front with just 1W of power; > 120 db with 30W. That would be heard by the team, 20 - 30 yards out from the edge of the field...
Not that Altec A7s are realistic either in terms of availability or practicality. I just mention them so illustratively you'll get an idea of what it would take to well accomplish your goal. You wont get that from one of those slanted auto boxes with two 12s and a couple of piezo tweeters. You'll need high efficiency and that usually means large. Horns with compression drivers and big, efficient bass drivers.
Altec Lansing Voice of the Theatre (VOTT) - Great Plains Audio - look at the picture. Can you build something like the A8? ;')
:
you could make a scaled Cerwin Vega folded horn for a 10" speaker such as Eminence's Delta 10A - then top that off with a cheap re-entrant horn (see Parts Express) and driver for your midrange. The tweeter could be whatever inexpensive you can source that's 103dB or more.
It would not "go low" - the woofer box would be about the size of some pc cases but a bit wider. It might not have the highest "fi" but might be fun plus pretty loud.
The woofer horn would be pretty light using well braced 12mm Baltic birch plywood. Those aluminum re-entrant horns are very light.
Dayton Audio RPH20 20" Round PA Horn Pair
It would not "go low" - the woofer box would be about the size of some pc cases but a bit wider. It might not have the highest "fi" but might be fun plus pretty loud.
The woofer horn would be pretty light using well braced 12mm Baltic birch plywood. Those aluminum re-entrant horns are very light.
Dayton Audio RPH20 20" Round PA Horn Pair
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