Grille covers on or off

[Franin]

I'm curious to know my sub in certain scenes kept hitting the grille cover was I meant to have the grille covers off when watching a movie? I was told by a friend that I should to let the sub preform at it's best, is that true?

 

[MidnightSensi]

Your grill cover should have enough clearance for the subwoofer driver. What subwoofer do you have?

Are you sure it isn't the subwoofer driver bottoming out from over-excursion?

 

[Mister House]

I find it hard to believe that you can hear the woofer hitting the grill. I am not calling you a liar by any means I just think that anything hitting a cloth surface is hard to hear.

 

[markw]

The cone is not hitting the grille cloth. The cone's excusrion won't allow it to travel that far out. There's some other problem at play here.

As to it affectng the sound in other ways, this is a non-issue with the frequency range reproduced by a subwoofer.

 

[rmk]

I'm curious to know my sub in certain scenes kept hitting the grille cover was I meant to have the grille covers off when watching a movie? I was told by a friend that I should to let the sub preform at it's best, is that true?

I seem to recall the same thing with my Fathoms Frank. I think is was a loose front baffle anchor bolt. The SS pegs that the grills attach to are also the bolts for the front baffle and if loose they can rattle. Check them out by hand and carefully tighten any loose ones with a Cresent Wrench (I think you guys call them Spanners)

OTOH, those drivers are capable of some serious excursion. Are you boosting the low frequencies with the ELF trims?

 

[Franin]

I seem to recall the same thing with my Fathoms Frank. I think is was a loose front baffle anchor bolt. The SS pegs that the grills attach to are also the bolts for the front baffle and if loose they can rattle. Check them out by hand and carefully tighten any loose ones with a Cresent Wrench (I think you guys call them Spanners)

OTOH, those drivers are capable of some serious excursion. Are you boosting the low frequencies with the ELF trims?

Hi RMK
Thanks will do it happened at the beginning helicopter scene in Transformers apart from that all is good. Though if I take grille off it doesn't make that sound. Were you also getting result? Haven't touched Elf trim at all. Forgot to add I moved the covers a bit forward out still leaving them on and it was fine.

Cheers

 

[Franin]

I seem to recall the same thing with my Fathoms Frank. I think is was a loose front baffle anchor bolt. The SS pegs that the grills attach to are also the bolts for the front baffle and if loose they can rattle. Check them out by hand and carefully tighten any loose ones with a Cresent Wrench (I think you guys call them Spanners)

OTOH, those drivers are capable of some serious excursion. Are you boosting the low frequencies with the ELF trims?

Hi RMK
By hand none of them move but I carefully put a spanner the right ones moved quite easily. I went to tighten them and got a tap sound off one of them. I Stopped did not go any futher I hoping I havent caused any damage. I tried it out doesnt seem to have any effect on the bass but still the same scene with helicopter makes noise on cover. I take it off its fine but it certainly moving quite a bit of air.

 

[rmk]

Hi RMK
By hand none of them move but I carefully put a spanner the right ones moved quite easily. I went to tighten them and got a tap sound off one of them. I Stopped did not go any futher I hoping I havent caused any damage. I tried it out doesnt seem to have any effect on the bass but still the same scene with helicopter makes noise on cover. I take it off its fine but it certainly moving quite a bit of air.

Hummm, don't tighten them any more but you should call your dealer and mention the driver impacting the grille. Is it happening with both Fathoms?

You could also call JL and get their take. Actually I think they look good with the grilles off so that is the best short term answer.

 

[Franin]

Hummm, don't tighten them any more but you should call your dealer and mention the driver impacting the grille. Is it happening with both Fathoms?

You could also call JL and get their take. Actually I think they look good with the grilles off so that is the best short term answer.

Just on one of them and on that particular scene. Wrote jl audio an email bit no reply.spoke to the distrubutor of JL here and he's going to access the construction papers of the unit to see what those pegs are. Told him there bolts but he was under he Impression they weren't and that tap sound that happened I could of busted a seal to the bolt/peg inside.

He has to get back to me know. He did tell me these subs are designed to move the excursion quite a bit, I guess know I wil have to wait to see if I have done any damage.

Cheers

 

[rmk]

Just on one of them and on that particular scene. Wrote jl audio an email bit no reply.spoke to the distrubutor of JL here and he's going to access the construction papers of the unit to see what those pegs are. Told him there bolts but he was under he Impression they weren't and that tap sound that happened I could of busted a seal to the bolt/peg inside.

He has to get back to me know. He did tell me these subs are designed to move the excursion quite a bit, I guess know I wil have to wait to see if I have done any damage.

Cheers

They are the front baffle bolts (do you see any others ) and I’m sure you didn’t damage them. JL’s chief engineer talked me though removing the baffle and driver once. I may be the only owner foolish enough to have to have done that myself.

Checking them ocassionally is actually a good idea as the driver can loosen them over time or so I was told by JL.

 

[Franin]

They are the front baffle bolts (do you see any others ) and I’m sure you didn’t damage them. JL’s chief engineer talked me though removing the baffle and driver once. I may be the only owner foolish enough to have to have done that myself.

Checking them ocassionally is actually a good idea as the driver can loosen them over time or so I was told by JL.

Well that's good to know as I know I did not overtighten them let alone tighten them fully. That tap sound sounded like a bolt that spung into place of that makes any sense.

I had fuses blown on both units same time I had to call out the jl guy to come and replace. There is no way I would do that let alone do what you did. Do the baffle bolts have a nut behind them to screw into ?

 

[Franin]

I'm curious to know my sub in certain scenes kept hitting the grille cover was I meant to have the grille covers off when watching a movie? I was told by a friend that I should to let the sub preform at it's best, is that true?

I find it hard to believe that you can hear the woofer hitting the grill. I am not calling you a liar by any means I just think that anything hitting a cloth surface is hard to hear.

Unfortunatley the surface of the grille is cloth and plastic through out.

 

[Franin]

Your grill cover should have enough clearance for the subwoofer driver. What subwoofer do you have?

Are you sure it isn't the subwoofer driver bottoming out from over-excursion?

without the covers works perfectly fine.

 

[Franin]

The cone is not hitting the grille cloth. The cone's excusrion won't allow it to travel that far out. There's some other problem at play here.

As to it affectng the sound in other ways, this is a non-issue with the frequency range reproduced by a subwoofer.

That Excusion bit around the subwoofer does, I think Without it works perfectly fine.

 

[rmk]

Well that's good to know as I know I did not overtighten them let alone tighten them fully. That tap sound sounded like a bolt that spung into place of that makes any sense.

I had fuses blown on both units same time I had to call out the jl guy to come and replace. There is no way I would do that let alone do what you did. Do the baffle bolts have a nut behind them to screw into ?

As I recall there are threaded inserts on the main enclosure that the grill pegs screw into. You really need to talk to JL about this and I would call tech support.

 

[Franin]

As I recall there are threaded inserts on the main enclosure that the grill pegs screw into. You really need to talk to JL about this and I would call tech support.

I will call tech support today to see if they can help. Thanks

 

[Franin]

try to call tech support more than a few times did not realise they get that busy.

 

[highfigh]

I'm curious to know my sub in certain scenes kept hitting the grille cover was I meant to have the grille covers off when watching a movie? I was told by a friend that I should to let the sub preform at it's best, is that true?

There's no way a grill cloth will resist the air pressurization from a subwoofer enough to matter. If the cloth had a vinyl backing, it would just become a diaphragm that responds to the cone's motion.

 

[rmk]

There's no way a grill cloth will resist the air pressurization from a subwoofer enough to matter. If the cloth had a vinyl backing, it would just become a diaphragm that responds to the cone's motion.

Apparently you have never seen a Fathom grille. The Fathom grilles are made of a good grade ABS plastic and covered with grille cloth. The structure is very strong and if the driver impacts the grille as apparently is happening with Franks unit, it would make a sound. I may have heard the same sound when I had my Fathoms.

 

[Franin]

There's no way a grill cloth will resist the air pressurization from a subwoofer enough to matter. If the cloth had a vinyl backing, it would just become a diaphragm that responds to the cone's motion.

Hi Highfigh,

I wish the were fully cloth but as rmk explained its ABS plastic throughout. I guess it has its pro's like kids trying to poke there finger in the cover.