I am building an off the grid sound system.It is going to be on a bike trailer and main goal is that it is loud (target for 100-200 cyclist pedaling in the street).I don't want bad quality sound, but I may sacrificed some very high fidelity if can reach more people, the audience are not audiophiles.
Currently I have :
With a lithium battery (36v nominal) and 1000WH and this class D amp ( 2.1)
AIYIMA Amplificador de alta potencia TPA3255, Clase D, HIFI 2,1, placa amplificadora de Audio Digital, 300W + 150W + 150W, para cine en casa|Amplificador| - AliExpress
it is a tpa3255 amplifier the specs are 300W for subwoofer and 150W for each channel at 4 ohms . Although this is very optimistic ( the subwoofer is BTL but the stereo channel are SE ).According to some reviews I have seen you can expect 90 W RMS for the woofer and 30 W RMS per channel for the HF.
I already have a subwoofer JBL Cs1214T ( 200RMS ) 12" woofer 4 ohm 35hz-200 hz 90 db
there is the frequency response of the ported subwoofer
https://www.avsforum.com/attachments/cs1214-tsp-pdf.2459670/
Then I need to choose the stereo loudspeakers, I am newbie on audio so I am a bit lost. I am looking for some speakers 35W RMS/ 4 ohms each ( if I choose 8 ohms the W RMS will be too low I think. I am open to any suggestion ( Full range, coaxial , open baffle,etc). As the sub only reach 200hz I was considering a set of full range speakers ( to have good mid tones , even if I have to sacrificed the high frequency a little bit, I don't mind to much)
So considering:
faital pro 4 4fe35" 30w
FaitalPRO 4FE35 - 4" Mid-range
or mojador spm-200X/4
MONACOR SPM-200X/4 - 8" Full-range
I was going to build a sealed enclosure but when using a speaker box simulation I realized the qts of these speakers are too high: Monaco qtc=0,97 and faital=0,73 . So no possible to have the recommended QTC around 0,7.
( there is a version of the faital with neodim magnets have a qtc=0,54)
1) It is sensible this type of speakers for the application and amplifier?
2) Will they work in a sealed enclouser or it is better another enclosure?
3) Will you recommend another approach?
Thanks in advance!
Currently I have :
With a lithium battery (36v nominal) and 1000WH and this class D amp ( 2.1)
AIYIMA Amplificador de alta potencia TPA3255, Clase D, HIFI 2,1, placa amplificadora de Audio Digital, 300W + 150W + 150W, para cine en casa|Amplificador| - AliExpress
it is a tpa3255 amplifier the specs are 300W for subwoofer and 150W for each channel at 4 ohms . Although this is very optimistic ( the subwoofer is BTL but the stereo channel are SE ).According to some reviews I have seen you can expect 90 W RMS for the woofer and 30 W RMS per channel for the HF.
I already have a subwoofer JBL Cs1214T ( 200RMS ) 12" woofer 4 ohm 35hz-200 hz 90 db
there is the frequency response of the ported subwoofer
https://www.avsforum.com/attachments/cs1214-tsp-pdf.2459670/
Then I need to choose the stereo loudspeakers, I am newbie on audio so I am a bit lost. I am looking for some speakers 35W RMS/ 4 ohms each ( if I choose 8 ohms the W RMS will be too low I think. I am open to any suggestion ( Full range, coaxial , open baffle,etc). As the sub only reach 200hz I was considering a set of full range speakers ( to have good mid tones , even if I have to sacrificed the high frequency a little bit, I don't mind to much)
So considering:
faital pro 4 4fe35" 30w
FaitalPRO 4FE35 - 4" Mid-range
or mojador spm-200X/4
MONACOR SPM-200X/4 - 8" Full-range
I was going to build a sealed enclosure but when using a speaker box simulation I realized the qts of these speakers are too high: Monaco qtc=0,97 and faital=0,73 . So no possible to have the recommended QTC around 0,7.
( there is a version of the faital with neodim magnets have a qtc=0,54)
1) It is sensible this type of speakers for the application and amplifier?
2) Will they work in a sealed enclouser or it is better another enclosure?
3) Will you recommend another approach?
Thanks in advance!
Regarding the efficiency: as our power supply is the battery, I want the system to be efficient ( that will increase the amount of time I could run it.)
Regarding the second question, not sure the typical situaton will be a lane of people ( typically around 7 m wide , and much longer in length)
Regarding the second question, not sure the typical situaton will be a lane of people ( typically around 7 m wide , and much longer in length)
The opportunity is there to use a high sensitivity compression tweeter and an efficiency increasing waveguide to cover the higher frequencies.
Efficiency at lower frequencies may take some space to do well, how much do you have?
And lastly, doing this all at really low frequencies gets more difficult. What is your frequency cutoff, or what do you require in bass?
Efficiency at lower frequencies may take some space to do well, how much do you have?
And lastly, doing this all at really low frequencies gets more difficult. What is your frequency cutoff, or what do you require in bass?
The most efficient way would be using a high efficient fullrange that is ok, like the Fane Sovereighn 12-250TC. As this is an outdoors system, the rising frequency won't be bad. This box can work in that config in a simple 50L sealed cabinet, and has an efficiency of 98dB/1w/1m so it won't use much power and go loud (109dB theoretically at 35w/1m). This driver was ment for such types of setup (smaller P.a. midtops). It has a high qts, but in reality that gives only a little 1dB bump (almost not hearable) below where you will use the driver with that woofer. And filling the box with stuffing will even reduce that. I did build a cabinet for that as a midtop for a garden system of a friend with a 15" (Faital 15FH500) woofer with an active analog crossover at 200Hz and that works flawless in his garden in the woods where he live.
With compression drivers and woofers you can also do it, but you will have to use a active crossover to really save power for that setup, as the compression driver is mostly more efficient and needs to be padded down. Passive this will just burn power to heat. Active means powering a dsp and 2 amps in stead of one (so it will actually take more power).
With compression drivers and woofers you can also do it, but you will have to use a active crossover to really save power for that setup, as the compression driver is mostly more efficient and needs to be padded down. Passive this will just burn power to heat. Active means powering a dsp and 2 amps in stead of one (so it will actually take more power).
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For the bass I already have bought a JBL subwoofer 12"
4 ohm 35hz-200 hz 90 db. 56liters ported
there is the frequency response of the ported subwoofer
https://www.avsforum.com/attachments/cs1214-tsp-pdf.2459670/
Regarding the compression tweeter , my main fear is that the mid frequencies will be too low combined with the subwoofer. As well the 2.1 amplifier is 35w per channel at 4 ohms but most tweeter are 8 oHMS so I will only have 17.5 watts per channel, not sure this is enough.
This speakers looks nice, but my amp gives 35w at 4ohms ,at 8hms will be only 17.5 watts per channel.That is why I was looking only at 4ohms full range speakers. But I see I will need a 95db/1w/1m 4 ohm speaker to have same dB with 35watts. I forget about that! Thanks for pointing out!, I may not restrict only to 4ohm speakers but 8hms with +3db sensibility
The speakers is a little bit price and if I need to buy two and build 2x 50l boxes it will be very big! My subwoofer is 60l so it will be +100l. Little to much. I may be looking for speakers half the size, and if possible little bit cheaper.
Thanks for the help!
High efficient and small are hard to find i'm affraid in fullrange. And otherwise you will end up with a way more complex system of a 2 way. The Fane is as small and cheap as it gets as far as i know. The only alternative is the Beyma 12GA50 that is as large, more expensive and less good. Smaller ones will be less sensitive so not fit for your low power amplifier, and not be cheaper.
I see, will it combine fine with the subwoofer I have. I found the frequency response of vented enclosure @2,83V. 4ohms
It is 50 liters box, mine 56 so should be pretty close
If I understood correctly for a good sound you want a flat SPL response across the frequency. So as I have difference impedances and watts I should check the final SPL¿?:
1) The subwoofer is 90db at 55hz @2.83V so in real is 87db at 55hz @1watt/1m .So if I have 90 W RMS available for the subwoofer that is 106,5 db at 1meter
2)If I choose the Fane Sovereighn 12-250TC. 98dB/1w/1m( 17.5W in one channel) this will be 110 db ( as waxx was saying). is this suitable¿?, But it is just 1 speaker, what happen to the other channel¿?. Can I leave it like without a speaker? I will gain +3db with the other speaker isn't it?, but I haven't got space for another 50 liter speaker in the trailer. I don't mind going mono if the amps can work like that (it is SE for each channel). Otherwise what happen if I use a smaller box? If I run a sealed enclosure calculator I get QTC=1 for 50L.
2b)What about Visaton BG17 it is 6"5 93db/1m/1w 8ohm so with 17,5w will be 105,4db, two of them 108 db.
VISATON BG 17 - 8 Ohm - 6.5" Full-range
Don't know how to calculate the box size because it Qts=0,74 don't know which Qtc should choose. This doesn't seem to be as good as the Fane but it is smaller.
If I can run mono, it seems better to use just the Fane over the stereo Visaton, the only doubt I have is the size in case of Visaton. If I choose QTC=1 I get 10 liters ( so It will be 20 liters both). Is it ok a QTC=1 I see the recommendation is around 0,7 but not posible to achieve obviously with qts=0,74
Thanks for your support I am learning a lot!
An externally hosted image should be here but it was not working when we last tested it.
It is 50 liters box, mine 56 so should be pretty close
If I understood correctly for a good sound you want a flat SPL response across the frequency. So as I have difference impedances and watts I should check the final SPL¿?:
1) The subwoofer is 90db at 55hz @2.83V so in real is 87db at 55hz @1watt/1m .So if I have 90 W RMS available for the subwoofer that is 106,5 db at 1meter
2)If I choose the Fane Sovereighn 12-250TC. 98dB/1w/1m( 17.5W in one channel) this will be 110 db ( as waxx was saying). is this suitable¿?, But it is just 1 speaker, what happen to the other channel¿?. Can I leave it like without a speaker? I will gain +3db with the other speaker isn't it?, but I haven't got space for another 50 liter speaker in the trailer. I don't mind going mono if the amps can work like that (it is SE for each channel). Otherwise what happen if I use a smaller box? If I run a sealed enclosure calculator I get QTC=1 for 50L.
2b)What about Visaton BG17 it is 6"5 93db/1m/1w 8ohm so with 17,5w will be 105,4db, two of them 108 db.
VISATON BG 17 - 8 Ohm - 6.5" Full-range
Don't know how to calculate the box size because it Qts=0,74 don't know which Qtc should choose. This doesn't seem to be as good as the Fane but it is smaller.
If I can run mono, it seems better to use just the Fane over the stereo Visaton, the only doubt I have is the size in case of Visaton. If I choose QTC=1 I get 10 liters ( so It will be 20 liters both). Is it ok a QTC=1 I see the recommendation is around 0,7 but not posible to achieve obviously with qts=0,74
Thanks for your support I am learning a lot!
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Ok ,I see. I realized you already answer about the qts as well!
One additional question: having the same 12" subwoofer driver , would it be a better configuration instead of ported for the subwoofer? I did asked because my initial plan was to have a smaller mids on top of the round sub. But now I have a to build a big enclosure on top of circular sub, which is not ideal for the integration in the trailer. I just wonder if could used the already existing 56l/ported (I could seal it if needed) for the fane. And build a subwoofer enclosure for the subwoofer driver ( a squared one below the circular one). Would be easier to integrate in my DIY trailer. A squared sub below and circular mid on top( IE I may used a 4rth order/6th order sub box?. The space I have is 67 cm length, 35cm width and could choose the height ( around 40cm maximum, less if possible).
Does it make sense from a audio point of view or better stick to the existing sub and make a 50l enclosure for the fane ?
One additional question: having the same 12" subwoofer driver , would it be a better configuration instead of ported for the subwoofer? I did asked because my initial plan was to have a smaller mids on top of the round sub. But now I have a to build a big enclosure on top of circular sub, which is not ideal for the integration in the trailer. I just wonder if could used the already existing 56l/ported (I could seal it if needed) for the fane. And build a subwoofer enclosure for the subwoofer driver ( a squared one below the circular one). Would be easier to integrate in my DIY trailer. A squared sub below and circular mid on top( IE I may used a 4rth order/6th order sub box?. The space I have is 67 cm length, 35cm width and could choose the height ( around 40cm maximum, less if possible).
Does it make sense from a audio point of view or better stick to the existing sub and make a 50l enclosure for the fane ?
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There is another option if the space of 67x35x height is not enough for the sub: Putting the existing 56l ( ported or sealed) enclosure with the fane on the bottom and the subwoofer on top. In this case I have more space ( above the wheels of the trailer) then I will have 67cmx67cm and the needed height with the 12" JBL driver for the sub enclosure.
if you want loud, high efficiency, compression driver is the way to go
110.7dB/w/m, covers 110Hz to 4kHz
Atlas Sound PD-5VH 40W Compression Driver
110.7dB/w/m, covers 110Hz to 4kHz
Atlas Sound PD-5VH 40W Compression Driver
@AllenB I will play mainly music.
@adason I didn't know about this kind of compression drivers, the ones I usually see covers higher frequencies.This seems the opposite better at mid frequencies than at high ones. It is quite interesting also because it won't occupy much volume compare to a midrange enclosure. Problem is the price is out of the range for this project
@adason I didn't know about this kind of compression drivers, the ones I usually see covers higher frequencies.This seems the opposite better at mid frequencies than at high ones. It is quite interesting also because it won't occupy much volume compare to a midrange enclosure. Problem is the price is out of the range for this project
Sure , it is just I didn't know they exists. I am new to audio and just associated compression driver to tweeters. Good to know. Are there single compression drivers for mid and high frequencies or this is just too much to ask? I guess it will be more difficult to build and be such efficient.
You can do 2-way with a compression driver. You can do 2-way for home use with a 1" driver, or 2-way for PA use with a 2" driver (for example).
Your choice of woofer is most important because it sets the sensitivity. If you try for deeper bass you can lose some sensitivity. Sometimes you want to use two or four woofers at a time.
It is difficult to know what you need for your application.
Your choice of woofer is most important because it sets the sensitivity. If you try for deeper bass you can lose some sensitivity. Sometimes you want to use two or four woofers at a time.
It is difficult to know what you need for your application.
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