I want to use four 8" long throw sub-woofers in a sealed enclosure. They're the tang band one with 12 mm x-max. My only problem is that they say for a sealed enclosure you gotta have a driver Q over .4
This particular driver's Q is .3. Would it work?
This particular driver's Q is .3. Would it work?
The speakers have a Vas - the suspension stiffness which is
expressed as an equivalent box volume.
This and the cone mass determine Fs - the free air resonant frequency.
When you put the driver in a box the box volume combines
with Vas to raise the stiffness and the resonant frequency
goes up and at the same time the Q goes up.
Its the Q of the driver in the box that counts not its free air Q.
So yes you can, absolutely, but you need the right box volume
per driver for the Q you want. But note that sometimes to get
the Q you want the resonant frequency in box can be too high.
Try playing around with one of the box calculators here :
http://www.speakerbuilding.com/software
🙂 /sreten.
expressed as an equivalent box volume.
This and the cone mass determine Fs - the free air resonant frequency.
When you put the driver in a box the box volume combines
with Vas to raise the stiffness and the resonant frequency
goes up and at the same time the Q goes up.
Its the Q of the driver in the box that counts not its free air Q.
So yes you can, absolutely, but you need the right box volume
per driver for the Q you want. But note that sometimes to get
the Q you want the resonant frequency in box can be too high.
Try playing around with one of the box calculators here :
http://www.speakerbuilding.com/software
🙂 /sreten.
Sure, but it will have a high F3, so will be more midbass than sub-woofer. Since you have four, you could put them in a low Q sealed cab (big) and use EQ to flatten the in-room response, at the expense of efficiency of course.
GM
GM
Cool.. thanks guys.
Actually raising the Q is exactly what i want to do. I'm thinking about using something like the ELF (or EAS as Rod Elliot calls it) subwoofer controller where you raise the Q of your woofer(s) to the point where the new resonance frequency is about the same as your main speakers (your satellites, midranges or whatever) and you operate your subwoofers below their new resonance peak. Then you use equlization and mega huge amps to get a perfectly flat responce down to 20hz.
The only thing that boggles me is this - From modeling, to get four of the woofers i want to use to have a resonance frequency as high as the mains i'd have to put them woofers in a ridiculously small sealed enclosure (.2 cubic feet for the four of them - 8 inchers!!!!) and then flatten out the responce and drive 400 watts into them!!! There is something slightly disturbing about that concept and common sense tells me it aint gonna happen. If it would work out it would of course be the greatest thing in the world - .2 cubic foot enclosure with that goes down to 20 hz. Hmmmm... what a nice thought
Although in reality i'd just end up blowing the woofers with the 400 watt amps. I guess i'll have to look for a better woofer for the job.... -or seek mental help
Actually raising the Q is exactly what i want to do. I'm thinking about using something like the ELF (or EAS as Rod Elliot calls it) subwoofer controller where you raise the Q of your woofer(s) to the point where the new resonance frequency is about the same as your main speakers (your satellites, midranges or whatever) and you operate your subwoofers below their new resonance peak. Then you use equlization and mega huge amps to get a perfectly flat responce down to 20hz.
The only thing that boggles me is this - From modeling, to get four of the woofers i want to use to have a resonance frequency as high as the mains i'd have to put them woofers in a ridiculously small sealed enclosure (.2 cubic feet for the four of them - 8 inchers!!!!) and then flatten out the responce and drive 400 watts into them!!! There is something slightly disturbing about that concept and common sense tells me it aint gonna happen. If it would work out it would of course be the greatest thing in the world - .2 cubic foot enclosure with that goes down to 20 hz. Hmmmm... what a nice thought
Although in reality i'd just end up blowing the woofers with the 400 watt amps. I guess i'll have to look for a better woofer for the job.... -or seek mental help
If you have a choice of speakers other than the TangBands, I suggest you look at Human Speakers 6" and 8" woofers, at about $60 USD each. They are intended for sealed systems and have been used in commercial speakers. The 8" woofers are very forgiving of box size. They are recommended by LDSG. The models of interest are
003 6" woofer
007 6" long throw woofer
008 6" 2 ohm long throw woofer
001 8" long throw woofer
005 8" extra long throw woofer
006 8" 2 ohm long throw woofer
http://www.humanspeakers.com
003 6" woofer
007 6" long throw woofer
008 6" 2 ohm long throw woofer
001 8" long throw woofer
005 8" extra long throw woofer
006 8" 2 ohm long throw woofer
http://www.humanspeakers.com
There's something extremely wrong with your modelling.
By mains I believe you mean your other speakers - there's
no reason why this frequency is relevant to the bass alignment.
Your subwoofer amplifier will control the frequency the sub
crosses over to the mains and this is low pass function,
completely seperate to the high pass function of the bass
alignment.
🙂 /sreten.
By mains I believe you mean your other speakers - there's
no reason why this frequency is relevant to the bass alignment.
Your subwoofer amplifier will control the frequency the sub
crosses over to the mains and this is low pass function,
completely seperate to the high pass function of the bass
alignment.
🙂 /sreten.
Actually, there is a very clear reason why it's relevant. If you visit Rod Elliot's sound pages and the subwoofer processor project,
http://sound.westhost.com/project48.htm
you'll see that the frequency at which the cut off for the main speakers is at is very relevant since this is where you have to bring the subwoofer's system resonance to.
This is not just 'adding' a subwoofer at any frequency. The purpose of this thing is to have a flat responce and smooth integration from mid to woofer down to 20 hz.
How much are the human drivers??
You are quite right,
sorry I should have read your post more thoroughly.
I couldn't find a TangBand 8" bass unit at Parts Express.
The post above states the Human drivers are around 60 USD each.
🙂 /sreten.
sorry I should have read your post more thoroughly.
I couldn't find a TangBand 8" bass unit at Parts Express.
The post above states the Human drivers are around 60 USD each.
🙂 /sreten.
Sreten,
Parts express doesn't carry that driver. Tang Band is a bit weird like that, you never know what to expect from them. Go here...
http://www.nuera-acoustic.ca
they carry the 8" tang band and an interesting 6X9 too along with a bunch of smaller ones.
I have to say that the human drivers look nice. But the tang bands are cheap.. and they look cute too 🙂
Parts express doesn't carry that driver. Tang Band is a bit weird like that, you never know what to expect from them. Go here...
http://www.nuera-acoustic.ca
they carry the 8" tang band and an interesting 6X9 too along with a bunch of smaller ones.
I have to say that the human drivers look nice. But the tang bands are cheap.. and they look cute too 🙂
Nice unit - good price !
I'd say forget about the EBS stuff.
Just put them in a box and design towards Q=0.6.
What box volume and box F do you get ?
🙂 /sreten.
I'd say forget about the EBS stuff.
Just put them in a box and design towards Q=0.6.
What box volume and box F do you get ?
🙂 /sreten.
Uh......I think you have it reversed.....
You should not try to put a driver with a Qts of over 0.4 in a ported enclosure.
Boom box city.............
Any driver will work in a sealed enclosure.
How well?......depends...........
Jocko
You should not try to put a driver with a Qts of over 0.4 in a ported enclosure.
Boom box city.............
Any driver will work in a sealed enclosure.
How well?......depends...........
Jocko
Jocko Homo
No one ever even mentioned the word "ported" in this thread. Where did you see me or anyone else say i want to put a driver with a Q of over .4 in a ported enclosure?
No one ever even mentioned the word "ported" in this thread. Where did you see me or anyone else say i want to put a driver with a Q of over .4 in a ported enclosure?
Sreten,
On second thought, i will not use the 8" tang band driver. I've found a few threads on the net suggesting that it needs a passive radiator to work properly and it'll cost more than the driver itself. pooo 🙁
On second thought, i will not use the 8" tang band driver. I've found a few threads on the net suggesting that it needs a passive radiator to work properly and it'll cost more than the driver itself. pooo 🙁
Jesus wept,
one minute your talking about EBS alignments requiring
massive EQ and the next your your listening to garbage.
The drivers parameters indicate reflex loading is the way
to go, that is no surprise, never was. You only need
passive radiators to achieve reflex alignments in smaller
volumes than the indicated reflex volumes.
But its still perfectly feasable to use the the drivers in a
sealed box but you may require some EQ, far less than
required for the EBS alignments.
The answer to the above will determine the EQ if needed.
🙂/sreten.
one minute your talking about EBS alignments requiring
massive EQ and the next your your listening to garbage.
The drivers parameters indicate reflex loading is the way
to go, that is no surprise, never was. You only need
passive radiators to achieve reflex alignments in smaller
volumes than the indicated reflex volumes.
But its still perfectly feasable to use the the drivers in a
sealed box but you may require some EQ, far less than
required for the EBS alignments.
The answer to the above will determine the EQ if needed.
🙂/sreten.
Hi Sardonx,
You can put almost any speaker or number of speakers in a closed box and correct its response at wish electronically as long as its Qt is below 0.5 to 0.6. But practical limitations limit electronic max bas boost to app. 6-10 dB. I experimented a lot with it in the past with good results. HERE is a .zip file with a short engineering note on what I did. It includes an Excel sheet where you can fill in driver params and box volume to see what you can expect. With this approach you can tailor box response to your taste and eventually room bas gain. Hope this is helpful.
Cheers 😉
You can put almost any speaker or number of speakers in a closed box and correct its response at wish electronically as long as its Qt is below 0.5 to 0.6. But practical limitations limit electronic max bas boost to app. 6-10 dB. I experimented a lot with it in the past with good results. HERE is a .zip file with a short engineering note on what I did. It includes an Excel sheet where you can fill in driver params and box volume to see what you can expect. With this approach you can tailor box response to your taste and eventually room bas gain. Hope this is helpful.
Cheers 😉
I mentioned "ported" because that is the only application that I can think of where the Qts of a driver would dictate which enclosure it will not work in.
Therefore......any driver can be used in a sealed enclosure.
Jocko
Therefore......any driver can be used in a sealed enclosure.
Jocko
Sreten,
for the 8" TB long throw. If you aim for a Qtc of .6 you get
a box volume of .27 cubic feet and an F3 of 67.71 hz. This is approximetly the size that i would visually like to see with that woofer.
Let me tell you why i could'nt use such a box in the beginning. I wanted to use the EAS in my system but the mid woofer that i ordered starts to roll off at 150hz. Anyway, for EAS you have to bring the sub's resonance up to that point.. and obviously 67 hz is not that point.
But it doesn't matter cuz i found out that you can use the linkwitz transform circuit and achieve nearly the same thing using any box volume. So I afterall may use that woofer 🙂)
Just out of curiosity.. what makes you choose a Q of .6?
Now i'm going to check out Pjotr's zip file
for the 8" TB long throw. If you aim for a Qtc of .6 you get
a box volume of .27 cubic feet and an F3 of 67.71 hz. This is approximetly the size that i would visually like to see with that woofer.
Let me tell you why i could'nt use such a box in the beginning. I wanted to use the EAS in my system but the mid woofer that i ordered starts to roll off at 150hz. Anyway, for EAS you have to bring the sub's resonance up to that point.. and obviously 67 hz is not that point.
But it doesn't matter cuz i found out that you can use the linkwitz transform circuit and achieve nearly the same thing using any box volume. So I afterall may use that woofer 🙂)
Just out of curiosity.. what makes you choose a Q of .6?
Now i'm going to check out Pjotr's zip file
Jocko
I know that this driver wont work in a ported box and that's why i started this thread asking about a *sealed* enclosure. But thanks anyways 🙂)
I know that this driver wont work in a ported box and that's why i started this thread asking about a *sealed* enclosure. But thanks anyways 🙂)
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