FI Q12 sounds horrible

[jman21 0]

Well you didn't say it was it a sealed enlcosure, just that it was 1.25cuft and not within spec so I assumed it was a ported enclosure because 1.25 is right in the middle of the sealed recommendation.

 

Since it's a sealed enclosure AND it appears to be unloading the sub at high volumes I would still highly suggest going over the enclosure with a fine tooth comb to make absolutely certain that it doesn't have any air leaks.  Any kind of air leak affects the performance of a sealed enclosure.  Surprisingly I've found over the years the most common places for air to leak from is where the sub mounts to the enclosure and around/through where the screws go through the frame to mount it and around/through terminal cups when they're used.  Enclosure carpet doesn't always work very well to help seal where the sub or terminal cups mount.  I've also seen air push right through cheap terminals and through the sub mounting holes when the hole was cut out with a jig saw and a little ob-longed.  Hell, on the enclosure I built for my XCON it had air pushing right through the screw threads.  I had to pull all the screws and put sealant on them to keep the air from pushing through them.

 

It's a sealed enclosure, there's not many more things to check.  Just because you put the sub and it's current enclosure in another vehicle and it did the same thing doesn't mean the sub is at fault.  If nothing else, with that you've proven it wasn't an issue with the amp or settings and have pretty well singled out the enclosure or the sub itself and my money is still on the enclosure.  The best way to test whether or not it's the sub itself is to try it in another enclosure.  Also you said you used liquid nails when building the enclosure which I've never had luck with.  Titebond II is the only glue to use when building enclosures in my opinion.  You also wouldn't believe the number of times I've heard someone complain about the noises coming from their subs thinking they were the problem only to find out what they were hearing was a panel on the enclosure knocking against another one because it was poorly built.  I'm not saying that's the exact problem with yours, but more often than not when it comes to an issue like the one you're having the enclosure is at fault and not the sub.  

 

Fi does make fantastic subs however the people who HAND BUILD these things are still human and can make a mistake.  There was a thread not too horribly long ago of a person who had an issue and it turned out to be something with the leads, or coil but it had to be one of the first times I've ever actually seen a manufacturing mistake.  Take into account the shear number of subs they sell through the Fi brand and the brands they OEM build for that have rarely ever had any problems at all and I think they do pretty damn good myself.  Testing in another enclosure is the sure fire way to know for certain.  If it still does it in another enclosure then the likelihood of the sub having a problem becomes much more prevalent, if it plays flawlessly then you know there has to be an issue with your enclosure.  That will be the fastest way to tell what's really going on.

thanks for this info.  the next step is to build a different box.  im going with a traditional sqaure sealed box just for test purpose. ill change the glue as well.  i grew up using liquid nail so its second nature.  i agree with all you said though.  im not giving up on FI but so far its a first for me to build a box for a sub and have it sound bad.  unless FI is a picky whore about enclosure and air space.  Is there an air space recommended other than factory requirment you think. Personally its hard to imagine that huge sub sitting in a .75-1 cft box.

[lithium 358]

 

 

Personally its hard to imagine that huge sub sitting in a .75-1 cft box.

make sure to factor in the subwoofer displacement when you're designing the box. 

[altoncustomtech 773]

 

Well you didn't say it was it a sealed enlcosure, just that it was 1.25cuft and not within spec so I assumed it was a ported enclosure because 1.25 is right in the middle of the sealed recommendation.

 

Since it's a sealed enclosure AND it appears to be unloading the sub at high volumes I would still highly suggest going over the enclosure with a fine tooth comb to make absolutely certain that it doesn't have any air leaks.  Any kind of air leak affects the performance of a sealed enclosure.  Surprisingly I've found over the years the most common places for air to leak from is where the sub mounts to the enclosure and around/through where the screws go through the frame to mount it and around/through terminal cups when they're used.  Enclosure carpet doesn't always work very well to help seal where the sub or terminal cups mount.  I've also seen air push right through cheap terminals and through the sub mounting holes when the hole was cut out with a jig saw and a little ob-longed.  Hell, on the enclosure I built for my XCON it had air pushing right through the screw threads.  I had to pull all the screws and put sealant on them to keep the air from pushing through them.

 

It's a sealed enclosure, there's not many more things to check.  Just because you put the sub and it's current enclosure in another vehicle and it did the same thing doesn't mean the sub is at fault.  If nothing else, with that you've proven it wasn't an issue with the amp or settings and have pretty well singled out the enclosure or the sub itself and my money is still on the enclosure.  The best way to test whether or not it's the sub itself is to try it in another enclosure.  Also you said you used liquid nails when building the enclosure which I've never had luck with.  Titebond II is the only glue to use when building enclosures in my opinion.  You also wouldn't believe the number of times I've heard someone complain about the noises coming from their subs thinking they were the problem only to find out what they were hearing was a panel on the enclosure knocking against another one because it was poorly built.  I'm not saying that's the exact problem with yours, but more often than not when it comes to an issue like the one you're having the enclosure is at fault and not the sub.  

 

Fi does make fantastic subs however the people who HAND BUILD these things are still human and can make a mistake.  There was a thread not too horribly long ago of a person who had an issue and it turned out to be something with the leads, or coil but it had to be one of the first times I've ever actually seen a manufacturing mistake.  Take into account the shear number of subs they sell through the Fi brand and the brands they OEM build for that have rarely ever had any problems at all and I think they do pretty damn good myself.  Testing in another enclosure is the sure fire way to know for certain.  If it still does it in another enclosure then the likelihood of the sub having a problem becomes much more prevalent, if it plays flawlessly then you know there has to be an issue with your enclosure.  That will be the fastest way to tell what's really going on.

thanks for this info.  the next step is to build a different box.  im going with a traditional sqaure sealed box just for test purpose. ill change the glue as well.  i grew up using liquid nail so its second nature.  i agree with all you said though.  im not giving up on FI but so far its a first for me to build a box for a sub and have it sound bad.  unless FI is a picky whore about enclosure and air space.  Is there an air space recommended other than factory requirment you think. Personally its hard to imagine that huge sub sitting in a .75-1 cft box.

 

 

Nope, I'd go with what Fi recommends.  As Brendan mentioned you have to factor in the volume the sub itself to the volume of the enclosure.  So say you're going to build an enclosure that is 1.5cuft NET, be sure to add the .16cuft of driver displacement for a total box volume of 1.66cuft total.  For example the outside dimensions of a box that size might be 16" W x 16.75" D x 14.5" H, internal dimensions being 14.5" W x 15.25" D x 13" H.

 

Every sub manufactured is picky about it's enclosure.  The enclosure is everything to how it performs and the type of enclosure and other details can change just how picky it is.  Sealed enclosures are the most forgiving and ported enclosures have to be much closer to the alignment specifications to work as designed.  The more complicated the enclosure alignment (such as 4th order bandpass and 6th order bandpass) the more critical the design and build of it is but one major thing is common among all of them and will make or break their success and that's being AIR TIGHT.

 

You said your current enclosure is 1.25cuft.  How sure are you of that figure?  Is that 1.25cuft including the sub displacement or not?  Any chance you can post up dimensions so we can help verify the internal volume?

 

Sorry I'm so inquisitive but the more information we have the more we can do to help you verify with as much certainty as possible where the problem truly lies.

[jman21 0]

i appreciate all the feedback but i have to come to the conclusion that the sub is bad.  the box recently built was 15 square.  its been in 3 boxes, its the sub not the enclosure. 

Edited March 23, 2014 by jman21

[jman21 0]

 

 

Well you didn't say it was it a sealed enlcosure, just that it was 1.25cuft and not within spec so I assumed it was a ported enclosure because 1.25 is right in the middle of the sealed recommendation.

 

Since it's a sealed enclosure AND it appears to be unloading the sub at high volumes I would still highly suggest going over the enclosure with a fine tooth comb to make absolutely certain that it doesn't have any air leaks.  Any kind of air leak affects the performance of a sealed enclosure.  Surprisingly I've found over the years the most common places for air to leak from is where the sub mounts to the enclosure and around/through where the screws go through the frame to mount it and around/through terminal cups when they're used.  Enclosure carpet doesn't always work very well to help seal where the sub or terminal cups mount.  I've also seen air push right through cheap terminals and through the sub mounting holes when the hole was cut out with a jig saw and a little ob-longed.  Hell, on the enclosure I built for my XCON it had air pushing right through the screw threads.  I had to pull all the screws and put sealant on them to keep the air from pushing through them.

 

It's a sealed enclosure, there's not many more things to check.  Just because you put the sub and it's current enclosure in another vehicle and it did the same thing doesn't mean the sub is at fault.  If nothing else, with that you've proven it wasn't an issue with the amp or settings and have pretty well singled out the enclosure or the sub itself and my money is still on the enclosure.  The best way to test whether or not it's the sub itself is to try it in another enclosure.  Also you said you used liquid nails when building the enclosure which I've never had luck with.  Titebond II is the only glue to use when building enclosures in my opinion.  You also wouldn't believe the number of times I've heard someone complain about the noises coming from their subs thinking they were the problem only to find out what they were hearing was a panel on the enclosure knocking against another one because it was poorly built.  I'm not saying that's the exact problem with yours, but more often than not when it comes to an issue like the one you're having the enclosure is at fault and not the sub.  

 

Fi does make fantastic subs however the people who HAND BUILD these things are still human and can make a mistake.  There was a thread not too horribly long ago of a person who had an issue and it turned out to be something with the leads, or coil but it had to be one of the first times I've ever actually seen a manufacturing mistake.  Take into account the shear number of subs they sell through the Fi brand and the brands they OEM build for that have rarely ever had any problems at all and I think they do pretty damn good myself.  Testing in another enclosure is the sure fire way to know for certain.  If it still does it in another enclosure then the likelihood of the sub having a problem becomes much more prevalent, if it plays flawlessly then you know there has to be an issue with your enclosure.  That will be the fastest way to tell what's really going on.

thanks for this info.  the next step is to build a different box.  im going with a traditional sqaure sealed box just for test purpose. ill change the glue as well.  i grew up using liquid nail so its second nature.  i agree with all you said though.  im not giving up on FI but so far its a first for me to build a box for a sub and have it sound bad.  unless FI is a picky whore about enclosure and air space.  Is there an air space recommended other than factory requirment you think. Personally its hard to imagine that huge sub sitting in a .75-1 cft box.

 

 

Nope, I'd go with what Fi recommends.  As Brendan mentioned you have to factor in the volume the sub itself to the volume of the enclosure.  So say you're going to build an enclosure that is 1.5cuft NET, be sure to add the .16cuft of driver displacement for a total box volume of 1.66cuft total.  For example the outside dimensions of a box that size might be 16" W x 16.75" D x 14.5" H, internal dimensions being 14.5" W x 15.25" D x 13" H.

 

Every sub manufactured is picky about it's enclosure.  The enclosure is everything to how it performs and the type of enclosure and other details can change just how picky it is.  Sealed enclosures are the most forgiving and ported enclosures have to be much closer to the alignment specifications to work as designed.  The more complicated the enclosure alignment (such as 4th order bandpass and 6th order bandpass) the more critical the design and build of it is but one major thing is common among all of them and will make or break their success and that's being AIR TIGHT.

 

You said your current enclosure is 1.25cuft.  How sure are you of that figure?  Is that 1.25cuft including the sub displacement or not?  Any chance you can post up dimensions so we can help verify the internal volume?

 

Sorry I'm so inquisitive but the more information we have the more we can do to help you verify with as much certainty as possible where the problem truly lies.

 

again i thank you for the help but i dont need advice on building, i am very aware of subtracting the box thickness as well as figuring cubic inches.  though i understand im sure you deal with alot of people who think you just put a speaker in a box and plug it in.

[lithium 358]

i appreciate all the feedback but i have to come to the conclusion that the sub is bad.  the box recently built was 15 square.  its been in 3 boxes, its the sub not the enclosure. 

 

i've yet to hear you describe what "bad" sounds like. given your description of the amp settings and so forth i assume you've got something set up incorrectly. 

[FocusOn20s 0]

Due to OP having a Low Qts sub in a sealed box, wouldn't that have adverse effects on the sound?

 

 

 

Q12
(D1/D2: Dual 2 Ohm, Cooling: No, Dust Cap: Fire, P Chamfer: No, High QTS: No, Spider: No, I Heat Ring: No, Internal Lead: No) Sealed box: .8-1.5 High QTScuft

 

Edited March 23, 2014 by FocusOn20s

[lithium 358]

 

Due to OP having a Low Qts sub in a sealed box, wouldn't that have adverse effects on the sound?

 

 

 

Q12

(D1/D2: Dual 2 Ohm, Cooling: No, Dust Cap: Fire, P Chamfer: No, High QTS: No, Spider: No, I Heat Ring: No, Internal Lead: No) Sealed box: .8-1.5 High QTScuft

 

 

good catch. it would certainly be better if it was ported. if he was only going to run sealed he should have gotten the high qts. should still work in either with a qts of .37

[THX_Elite 26]

I too am curious as to what the sub itself is doing to "sound bad"..may or may not shed some light on other issues.

[Fi 4 life 0]

If the OP did not get the high QTS option then it should be used in a ported enclosure. QTS has a major role in what kind of box the driver should be installed in. Low QTS = ported. Medium = sealed. High = IB.

These are about #'s and not to be taken as exact, but in the end I'd listen to the guys who made these speakers and their suggestions for what kind dand size of box thats tuned between a certain range of hertz to be tuned to for what you should do box wise for their products.

[cloud77 28]

If the OP did not get the high QTS option then it should be used in a ported enclosure. QTS has a major role in what kind of box the driver should be installed in. Low QTS = ported. Medium = sealed. High = IB.

These are about #'s and not to be taken as exact, but in the end I'd listen to the guys who made these speakers and their suggestions for what kind dand size of box thats tuned between a certain range of hertz to be tuned to for what you should do box wise for their products.

No. High Qts only makes the coil gap a bit larger to take away some motor force away from the driver and helps with maintaining its linearity at high excursion levels. A sub without the HQTS option will still perform well in reasonable volumes of a sealed enclosure with good output.