Hello, I have build an off the grid system, based of 36v batteries, with 1000wh capacity. Everything is carried in a bicycle trailer and play music outdoor to 50 100 people
It has a 12" JBL subwoofer 50l box 4ohms ( rate at 200rms) and a 12" full range fane sovereign ( rate at 250 RMS) 52 liter enclouser 8ohms
Currently I am using an aiyima 2.1 tpa3255 amplifier. But I want more power.
https://m.es.aliexpress.com/item/40...&spm=a219c.12010612.8148356.10.3cf47340bNi80O
Currently based on battery consumption it runs at 30w or 40w at max volumen. I could run it 48h non stop!. but I will want to run it with more power, something close to the the RMS power of the speakers.
I have a preamp to step up the input voltage of the music.
The current amp 2.1 is BTL for the subwoofer and se for each channel , and only using one channel for the fane and subwoofer . Not ideal.
I don't know if I could take more power from the actual amplifier , or I need to switch. The specifications advertised are wrong, but I realized that too late.
My idea is to change to two mono amp which are pbtl, to get the max power possible from the 36v battery.
Either a tpa3255 from 3e or a wondom
WONDOM AA-AB3124?
I will need to split frequencies somehow , probably a DSP because I want the system to be efficent.
What amp do you recommend? Is there a better combination of amps or other way run the system .
It has a 12" JBL subwoofer 50l box 4ohms ( rate at 200rms) and a 12" full range fane sovereign ( rate at 250 RMS) 52 liter enclouser 8ohms
Currently I am using an aiyima 2.1 tpa3255 amplifier. But I want more power.
https://m.es.aliexpress.com/item/40...&spm=a219c.12010612.8148356.10.3cf47340bNi80O
Currently based on battery consumption it runs at 30w or 40w at max volumen. I could run it 48h non stop!. but I will want to run it with more power, something close to the the RMS power of the speakers.
I have a preamp to step up the input voltage of the music.
The current amp 2.1 is BTL for the subwoofer and se for each channel , and only using one channel for the fane and subwoofer . Not ideal.
I don't know if I could take more power from the actual amplifier , or I need to switch. The specifications advertised are wrong, but I realized that too late.
My idea is to change to two mono amp which are pbtl, to get the max power possible from the 36v battery.
Either a tpa3255 from 3e or a wondom
WONDOM AA-AB3124?
I will need to split frequencies somehow , probably a DSP because I want the system to be efficent.
What amp do you recommend? Is there a better combination of amps or other way run the system .
Can you afford to double up on the "fane sovereign" part? Might as well make use of the power that you've got / how these amplifier types are designed for anticipated use (2.1)...
No I do not have room for another fane. Nevertheless is not weight efficient ( it will add more than 10kg speaker + enclouser, and need to pedal the bike trailer. Currently the fane is not using 10%, of the RMS power , so increasing power would be more efficient.
I may used the current amp for the subwoofer and add two tweeters , and get another mono amp for the fane. It is another possibility but neither used full potencial of the subwoofer...
I would want to get al least 100 150 w from the fane and the sub, IE 300w total, which is the actual power I sized the batteries for.
I may used the current amp for the subwoofer and add two tweeters , and get another mono amp for the fane. It is another possibility but neither used full potencial of the subwoofer...
I would want to get al least 100 150 w from the fane and the sub, IE 300w total, which is the actual power I sized the batteries for.
More power requires more voltage. Even with the best possible bridge amplifier, the most that sub will see is about 150 watts on a 36 volt battery. The mains only about 20 watts apiece running half bridge. A 48 volt system would get you around 250W. That’s not really a lot louder and might be all the sub will take. You could certainly get more out of the mains by running those in BTL - around 75 watts apiece on the 36 volts. Then run the crossover frequency down and let the mains take care of *some* of the bass. Just use the sub where the more efficient Fanes can’t go.
If that’s all the battery you can have, the only real way to get more power would be to configure it for 12 volts and use a car amp (with a built in DC-DC converter) to get you to a higher wattage. That will be less expensive than building a custom DC-DC converter and using a 500 or 1000 watt ICEpower module. Might have to upgrade the sub - if it’s only good for 200 watts you’re not too far from its limits now.
If that’s all the battery you can have, the only real way to get more power would be to configure it for 12 volts and use a car amp (with a built in DC-DC converter) to get you to a higher wattage. That will be less expensive than building a custom DC-DC converter and using a 500 or 1000 watt ICEpower module. Might have to upgrade the sub - if it’s only good for 200 watts you’re not too far from its limits now.
Why I don't understand is why the sub , which is bridge is not taking more power, total power I am getting is 30-40 total including the fane
I will be happy with 100 watts each with two mono pbtl amps, but doubt I can reach it if the specs are like the one I bought, maybe 3e or sure are better?
I am new to audio, I understand that your power will be V*V/R been r resistance of the speaker. So more v more power. But how car audio allow for higher power when they use only 12v?
Stepping from 36v to 12v will have additional looses isn't it?
The batteries are lithium, and want to keep them 36v cos the charger are set to that voltage
I will be happy with 100 watts each with two mono pbtl amps, but doubt I can reach it if the specs are like the one I bought, maybe 3e or sure are better?
I am new to audio, I understand that your power will be V*V/R been r resistance of the speaker. So more v more power. But how car audio allow for higher power when they use only 12v?
Stepping from 36v to 12v will have additional looses isn't it?
The batteries are lithium, and want to keep them 36v cos the charger are set to that voltage
You need to use a boost converter to increase the battery voltage for a higher powered amp. Car audio amps often have a boost converter integrated into the amplifier which is how they get the higher DC bus voltage to put more power into the speaker. The amps are limited by the voltage swing they can put across the voice coils of the drivers which usually have 8 ohm or sometimes 4 ohm resistance.
I think if I were to do this, I'd run it mono bi-amped into a hi-efficiency coaxial driver, ala Rod's PA box project:
Project 137-1
He runs it bridged and a 36 volt supply would give you ~ 65 watts rms for the woofer and plenty enough to drive the compression tweeter to equal the woofer output. With a 95 db-efficient woofer, that's about 116 db SPL peak, plus 3 db for the tweeter. Allowing for 13 db of headroom should allow playing at 106 db SPL rms. That's pretty loud!!
Project 137-1
He runs it bridged and a 36 volt supply would give you ~ 65 watts rms for the woofer and plenty enough to drive the compression tweeter to equal the woofer output. With a 95 db-efficient woofer, that's about 116 db SPL peak, plus 3 db for the tweeter. Allowing for 13 db of headroom should allow playing at 106 db SPL rms. That's pretty loud!!
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The only two ways to get more power is to increase voltage given the same load, or reduce load impedance given the same supply voltage.
That is why you're not getting full output of the amplifiers. The 3255 will need a boost converter and the 3251 PBTL will run at maximum power, provided you can have a load ~2 ohms.
Every car amp (that I know of) uses a boost converter to push the voltages up, and have output stages rated to 2 ohm operation. This is the only way to promise hundreds of watts from 12V. Else with and 8 ohm load and a single 36V supply, you can't get more than 50W with a bridged amplifier.
Boost converters are very variable in performance. Cheap ones that you can buy online can be terribly inefficient, and not even capable of proper audio performance due to their slow response to peak demands. Properly built, they can be formidable, but finding a good one off-the-shelf will be tricky.
That is why you're not getting full output of the amplifiers. The 3255 will need a boost converter and the 3251 PBTL will run at maximum power, provided you can have a load ~2 ohms.
Every car amp (that I know of) uses a boost converter to push the voltages up, and have output stages rated to 2 ohm operation. This is the only way to promise hundreds of watts from 12V. Else with and 8 ohm load and a single 36V supply, you can't get more than 50W with a bridged amplifier.
Boost converters are very variable in performance. Cheap ones that you can buy online can be terribly inefficient, and not even capable of proper audio performance due to their slow response to peak demands. Properly built, they can be formidable, but finding a good one off-the-shelf will be tricky.
I would go for a TPA3255 based amp
On 36 V you would get 120W for sub and 2x 69W for mid/high
with 48V this doubles, so you can add another 12V battery when you want more.
DC 30-48V TPA3255 Chip Class-D Stereo Audio Amplifier: Amazon.in: Electronics
That one is unavailable but there are other boards with the chip
On 36 V you would get 120W for sub and 2x 69W for mid/high
with 48V this doubles, so you can add another 12V battery when you want more.
DC 30-48V TPA3255 Chip Class-D Stereo Audio Amplifier: Amazon.in: Electronics
That one is unavailable but there are other boards with the chip