No, this is, if because SPL it can not cross to a small speaker (diameter) and with a high SPL and a small (one) number of drivers.
bass is directional above 60hz ish.
good systems use the subs to play the super low end... <50hz
most low end monster subs do not like to play over >60hz.
therefore a 50hz crossover sub needs to be a good sub.
not always $$$ or size.
box type and size is a huge factor.
subs like this generally needs an active crossover. subsonic, low pass,& equalizer for good results.
my tc9 10" off 800rms loves 25hz-55hz ssf24db lp18db nothing else.
good systems use the subs to play the super low end... <50hz
most low end monster subs do not like to play over >60hz.
therefore a 50hz crossover sub needs to be a good sub.
not always $$$ or size.
box type and size is a huge factor.
subs like this generally needs an active crossover. subsonic, low pass,& equalizer for good results.
my tc9 10" off 800rms loves 25hz-55hz ssf24db lp18db nothing else.
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what I mean is if you have great drivers covering all other frequencies but are looking for great subsonics crossed at 50hz/24db,would one be better off buying 2/side Aura NS18($1200/side) or say 4/side-15"($800/side)...I thought someone once said if you are going to cross at 40-50hz,you donnot need to buy such quality drivers???
I am wanting this in a reference designed 4.5way(My 4-12'AT woofers will hit 25hz and are crossed at 150hz).
Yes on SPL also,but clean,clear SPL.
I am wanting this in a reference designed 4.5way(My 4-12'AT woofers will hit 25hz and are crossed at 150hz).
Yes on SPL also,but clean,clear SPL.
for the low end it is based on cone areas and displacement. and then budget. power concerns. box size.
two 18's of high quality may be smaller box. but more power needed. more displacement less cone area.
four 15 of lower quality may be huge box and less power. more cone area less displacement.
same results
cone area.
One 8" = 50.27
One 10" = 78.54
One 12" = 113.1
One 15" = 176.71
One 18" = 254.47
Two 8" = 100.53
Two 10" = 157.08
Two 12" = 226.19
Two 15" = 353.43
Two 18" = 508.94
Three 8" = 150.8
Three 10" = 235.62
Three 12" = 339.29
Three 15" = 530.14
Three 18" = 763.41
Four 8" = 201.06
Four 10" = 314.16
Four 12" = 452.39
Four 15" = 706.86
Four 18" = 1017.87
two 18's of high quality may be smaller box. but more power needed. more displacement less cone area.
four 15 of lower quality may be huge box and less power. more cone area less displacement.
same results
cone area.
One 8" = 50.27
One 10" = 78.54
One 12" = 113.1
One 15" = 176.71
One 18" = 254.47
Two 8" = 100.53
Two 10" = 157.08
Two 12" = 226.19
Two 15" = 353.43
Two 18" = 508.94
Three 8" = 150.8
Three 10" = 235.62
Three 12" = 339.29
Three 15" = 530.14
Three 18" = 763.41
Four 8" = 201.06
Four 10" = 314.16
Four 12" = 452.39
Four 15" = 706.86
Four 18" = 1017.87
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Thanks Slain
I can get some Canadian made 15" subs(IST) for $199ea ..they are a sub used in the car industry(but are they not all used there).
2.5ft3 (sealed)ea will work well on these ...I see Aura ns18's will be back in Feb 2012 and will require 4-5ft3/ea..Power is no problem.
If Aura still had the 15"'s i would buy them.
TC Sounds are a little crazy in price for me.
I have a pair of CSS SDX 15's that I am experimenting with in a 3ft3 sealed box.I will keep them for my HT.
The other subs will be either side or rear firing in my modular mains consisting of..
SS 7100-hi
ATC 75/150"S"-mid
Volt-8" or 10"(experimenting right now)-mid bass
custom AT 12"-low
sub low-?
my design will be W.MB.MTM.MB.W with either side or rear firing subs
I can get some Canadian made 15" subs(IST) for $199ea ..they are a sub used in the car industry(but are they not all used there).
2.5ft3 (sealed)ea will work well on these ...I see Aura ns18's will be back in Feb 2012 and will require 4-5ft3/ea..Power is no problem.
If Aura still had the 15"'s i would buy them.
TC Sounds are a little crazy in price for me.
I have a pair of CSS SDX 15's that I am experimenting with in a 3ft3 sealed box.I will keep them for my HT.
The other subs will be either side or rear firing in my modular mains consisting of..
SS 7100-hi
ATC 75/150"S"-mid
Volt-8" or 10"(experimenting right now)-mid bass
custom AT 12"-low
sub low-?
my design will be W.MB.MTM.MB.W with either side or rear firing subs
Wrong Question
Until crossover frequency is at a wave length comparable to driver dimensions there is no driver upper bound issues to be considered here. The issues remain focused at the driver lower frequency bound alone, where volume displacement capability reigns supreme. How low and strong do you want to go there? To spelunk the first two octaves of program signal, 16-64 Hz, recommend multiple servo-controlled subs with lots of volume displacement. Some examples follow:
Rythmik Audio
Rythmik Audio • Servo subwoofer products
Velodyne Acoustics
Digital Drive PLUS Series - Shop By Series > - Subwoofers > - Shop
Regards,
WHG
Until crossover frequency is at a wave length comparable to driver dimensions there is no driver upper bound issues to be considered here. The issues remain focused at the driver lower frequency bound alone, where volume displacement capability reigns supreme. How low and strong do you want to go there? To spelunk the first two octaves of program signal, 16-64 Hz, recommend multiple servo-controlled subs with lots of volume displacement. Some examples follow:
Rythmik Audio
Rythmik Audio • Servo subwoofer products
Velodyne Acoustics
Digital Drive PLUS Series - Shop By Series > - Subwoofers > - Shop
Regards,
WHG
Hi John,
Most car subs intended for small sealed boxes are well at home in the car audio industry where there is a ton of room gain from the cabin of the car. In a home application where you have a lot less gain, especially if this is in a dedicated listening room, the characteristics of many car oriented subs prove to be out of balance with the goals of the application. You can generally get more clean low frequency reproduction in properly designed BR boxes using drivers with more well rounded characteristics that lend themselves to efficiency. For 20-50hz reproduction, I suggest 18-24" size drivers. They can displace more air with less cone movement, the result is "usually" lower distortion and higher efficiency.
If you have a link to the spec page of the drivers you have in mind though I'd be happy to throw up some comparisons.
Eric
Most car subs intended for small sealed boxes are well at home in the car audio industry where there is a ton of room gain from the cabin of the car. In a home application where you have a lot less gain, especially if this is in a dedicated listening room, the characteristics of many car oriented subs prove to be out of balance with the goals of the application. You can generally get more clean low frequency reproduction in properly designed BR boxes using drivers with more well rounded characteristics that lend themselves to efficiency. For 20-50hz reproduction, I suggest 18-24" size drivers. They can displace more air with less cone movement, the result is "usually" lower distortion and higher efficiency.
If you have a link to the spec page of the drivers you have in mind though I'd be happy to throw up some comparisons.
Eric
I think the massive magnets and crazy amplifier specs coupled with digital eq in store bought stuff like Velodyne and JL Audio have sort-of negated the "bigger driver is better" arguments. I was convinced years ago that a more accurate small woofer is better if the cabinet/porting is correct. (Say what you will about SPL, most do not live in cathedrals.)
Look at the specs on the Velo DD-10: 18-120Hz with a 19 pound magnet. That is a top end many would scoff at. I don't. (Three inches of push/pull?)
The real issue with going low is room dynamics. You need a giant room to really let 18Hz shine (not to mention good program material) but the effectively instant digital eq changes that.
This place is about DIY and I'm sure this sort of stuff will be DIY shortly (if not now) but Velo is widely available. Go to a store and hear for yourself.
BTW: the JL Audio home line has even more crazy specs (at a correspondingly higher price.)
P
Look at the specs on the Velo DD-10: 18-120Hz with a 19 pound magnet. That is a top end many would scoff at. I don't. (Three inches of push/pull?)
The real issue with going low is room dynamics. You need a giant room to really let 18Hz shine (not to mention good program material) but the effectively instant digital eq changes that.
This place is about DIY and I'm sure this sort of stuff will be DIY shortly (if not now) but Velo is widely available. Go to a store and hear for yourself.
BTW: the JL Audio home line has even more crazy specs (at a correspondingly higher price.)
P
Hey John, just a quick note, if you look in the swap meet, there is a thread with some TC Sounds drivers for sale. I think he had 4 15" and was asking $125 ea.
Peace,
Dave
P.S. I have no affiliation whatsoever with the seller, just happened to see both threads and thought I would try to help.
Peace,
Dave
P.S. I have no affiliation whatsoever with the seller, just happened to see both threads and thought I would try to help.
When you say small sealed, how small are you aiming for? In my experience, small sealed configurations on that scale will create other problems... Like where are you going to get enough mains power?
Just some quick modeling reveals that a single 21" RCF driver in a 11ft^3 vented box (with ~6ft^3 additional for the vent, so 17ft^3 total box size), once equalization is accounted for, will play down to 20hz just as loud as 4xTC 15" drivers in an equal amount of sealed box space (17ft^3 in each comparison). However, the power requirements to do so are 1/3rd. So that's about 1/4th the driver cost (assuming new), 1/3rd the amplification requirements, and equal box space delivering the same performance.
I can't fathom doing a sealed box build personally.
Just some quick modeling reveals that a single 21" RCF driver in a 11ft^3 vented box (with ~6ft^3 additional for the vent, so 17ft^3 total box size), once equalization is accounted for, will play down to 20hz just as loud as 4xTC 15" drivers in an equal amount of sealed box space (17ft^3 in each comparison). However, the power requirements to do so are 1/3rd. So that's about 1/4th the driver cost (assuming new), 1/3rd the amplification requirements, and equal box space delivering the same performance.
I can't fathom doing a sealed box build personally.
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thanks Md
I was hoping you would look at the IST 15.2 woofers and see if they are usable as I can get 8 of those for the price of 4 TC.
I was looking further into those TC1000's for sale here but they are 20lb,bottom of the line woofers that sold for $150 new(at times) in the past.
17.5 cubic feet is a little large for me as I was into 10 ft3 max/side.
I was hoping you would look at the IST 15.2 woofers and see if they are usable as I can get 8 of those for the price of 4 TC.
I was looking further into those TC1000's for sale here but they are 20lb,bottom of the line woofers that sold for $150 new(at times) in the past.
17.5 cubic feet is a little large for me as I was into 10 ft3 max/side.
I agree, but I love the tiny sealed box I use in my station wagon. It's a JL Audio 6W3 powered by a JL Audio Slash V2/250W bass amp. The enclosure takes no space and it's the hardest working piece I've ever heard.
Also, my Infinity speakers are also sealed woofers (2x2x12) so maybe cost isn't the only issue in bass quality.
P
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