Hello, I have a case specific problem with my JL 12w7 I purchased recently, I have had it professionally put in a sealed enclosure last night and I have a "clud" type of sound when I turn the bass up, The sub sounds great on low to mid volume but as soon as I crank it, it almost sound like its bottoming out, to describe the sound best: Imagine hitting a piece of plywood with a rubber mallet, so instead of a thud its a clud lol. I just had it pulled from a JL HO box (that im selling now) in which it sounded great and was much louder and did not have distortion until the very highest settings, but that box took all my room and made my ears ring, plus I prefer sealed over ported, and the new sealed box sounds dang near perfect until you crank. So please don't tell me "switch back" or buy a new box, I just dropped a lot of money on this set up not about to start over.
Here is my setup, please let me know if I miss some vital details:
1. 1 JL12W7 in a ~1.4 ft^3 +driver sealed box, with fiberglass in corners.
2. 1 JL 500/1 amplifier
3. 1 JL 300/4 amplifier for speakers
4. JL c2 component speakers, 3 way in back 2 way in front.
5. Big 3 upgrade with 4 gauge wire.
6. 4 gauge wire to amps.
7. New quality RCA's and remote line.
8. 1.5 farad capacitor wired in.
9. All types of music.
10. clud sound mainly in kicks and beats.
11. Fuse to match.
12. Sub placement is sideways firing towards the left ~12" or so from the wall panel in the sedan. right behind the back seat.
13. Toyota Corrola 2008
14. %15 dynamatted and puttied the panels to reduce rattle.
15. 3/4 MDF box with double for the baffle, minimal bracing.
16. Aluminium bar grille JL
17. The woofer was firing straight into MDF 8 inches or so clearance, I thought that was what was causing the sound but when I pulled the panel off I did not notice a big improvement in my problem.
Please help me with anything you can, I am a bit upset since it seems no matter how hard I try or how much money I put in this I can't get it to sound quite right! Darn it! lol
I can add pictures by request
Here is my setup, please let me know if I miss some vital details:
1. 1 JL12W7 in a ~1.4 ft^3 +driver sealed box, with fiberglass in corners.
2. 1 JL 500/1 amplifier
3. 1 JL 300/4 amplifier for speakers
4. JL c2 component speakers, 3 way in back 2 way in front.
5. Big 3 upgrade with 4 gauge wire.
6. 4 gauge wire to amps.
7. New quality RCA's and remote line.
8. 1.5 farad capacitor wired in.
9. All types of music.
10. clud sound mainly in kicks and beats.
11. Fuse to match.
12. Sub placement is sideways firing towards the left ~12" or so from the wall panel in the sedan. right behind the back seat.
13. Toyota Corrola 2008
14. %15 dynamatted and puttied the panels to reduce rattle.
15. 3/4 MDF box with double for the baffle, minimal bracing.
16. Aluminium bar grille JL
17. The woofer was firing straight into MDF 8 inches or so clearance, I thought that was what was causing the sound but when I pulled the panel off I did not notice a big improvement in my problem.
Please help me with anything you can, I am a bit upset since it seems no matter how hard I try or how much money I put in this I can't get it to sound quite right! Darn it! lol
I can add pictures by request
JL w7 Problems
I never actually checked with an SPL meter, but I got roughly 5 times more output, (perceived) with the HO Box, I just turned the sub facing the rear (Which messes up my whole plan with the custom install) but I figured out some work arounds... turning it backwards helped by huge amount! Had no idea placement mattered that much.. my installer says the sound waves were canceling each other out.. I just added a few feet of wire so I can mess with the placement till I have it just right. Also I believe the installer used WINISD to build the box, he seems to know fairly well what he was doing but not necessarily a pro. Any other suggestions that would help with reducing distortion and increasing spl in a sealed box? I appreciate your reply thank you
I never actually checked with an SPL meter, but I got roughly 5 times more output, (perceived) with the HO Box, I just turned the sub facing the rear (Which messes up my whole plan with the custom install) but I figured out some work arounds... turning it backwards helped by huge amount! Had no idea placement mattered that much.. my installer says the sound waves were canceling each other out.. I just added a few feet of wire so I can mess with the placement till I have it just right. Also I believe the installer used WINISD to build the box, he seems to know fairly well what he was doing but not necessarily a pro. Any other suggestions that would help with reducing distortion and increasing spl in a sealed box? I appreciate your reply thank you
Also wanted to add, It was the official red eye JL HO ported box for the 12 inch W7. From what I gather my sound would reflect off each other and cancel out, a different placement has helped a whole lot but I'm stilll missing about 40% of my output from the HO to the new sealed.. is that normal? Going from ported to sealed I hear drops 3db is that equal to about 40-50%? by placing the woofer in a rear firing position it has removed most of the "clud" sound... a couple questions:
Does having MDF in the front of the cone or to the side of it effect sound adversely?
is rear firing typically the best position in a sedan?
Does the size of a sealed box effect SPL? If so smaller or bigger for louder?
My installer says he put polyfill in the box, Im not too certain because of his hesitation, will not having it make a big difference?
how tight does the box have to be? Sealed to the point where its waterproof? Or tiny holes or cracks wont make a noticeable difference?
Thank You so much fellow audio gurus your replies are greatly appreciated
Does having MDF in the front of the cone or to the side of it effect sound adversely?
is rear firing typically the best position in a sedan?
Does the size of a sealed box effect SPL? If so smaller or bigger for louder?
My installer says he put polyfill in the box, Im not too certain because of his hesitation, will not having it make a big difference?
how tight does the box have to be? Sealed to the point where its waterproof? Or tiny holes or cracks wont make a noticeable difference?
Thank You so much fellow audio gurus your replies are greatly appreciated
From the data here:
http://mediacdn.jlaudio.com/media/mfg/9013/media_document/live_1/8_13W7_MAN.pdf?1317790345
It seems to be very forgiving in a sealed box.
Here is what I got for 1, 1.4, and 2 cuft
http://mediacdn.jlaudio.com/media/mfg/9013/media_document/live_1/8_13W7_MAN.pdf?1317790345
It seems to be very forgiving in a sealed box.
Here is what I got for 1, 1.4, and 2 cuft
Attachments
1) At 1000 Hz, a 10 dB change in level sounds twice or half as loud.
At 20 Hz, a 5 dB change in level sounds twice or half as loud.
2) A 3 dB change is equivalent to double the power, depending on the frequency it would be from around 60% to 33% different in perceived level.
3) What is the purpose of MDF in front of the cone or to the side of it?
4) Hard to say what makes for "the best position" for a sub in a sedan, every different position will affect the level in the driver's seat differently at different frequencies.
5) The size of the sealed box will affect frequency response and excursion, a big box will extend lower but the speaker can "bottom out" ("clud"?) with less power, a "too small" box will take more power without overexcursion and will be louder at a higher frequency.
Speaker bottoming out or amp clipping or both might sound like a "clud" noise filtered through seat material, but more like a "clack" with the trunk lid open.
6) Complete stuffing of the box with polyfill can make the apparent box size about 15% larger, not a big difference.
7) Air leaks can make a noticeable difference, and would allow the driver more excursion with less sound level.
If the cabinet is not bolted or rachet strapped in place, at high drive levels the weight of the moving cone could cause the box itself to "hammer" the trunk, which might be the sound you hear.
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Jl w7
Thank you weltersys, you explained quite a bit of the things that were puzzling me, after messing with the placement I found the best place was on the far left right behind the seat facing to the rear of the car, the "clud" sound only appears when the volume is beyond any comfortable level now, looks like I figured out the biggest issue, placement placement placement....
Now I only hear (other than the sweet sweet bass) plastic rattle and some clanging on loud volumes, seems like the plastics rattle in the mid bass and the metal at a lower frequency, I also suspect you are right about the box hammering my trunk... The thing won't be attached till tomorrow and that may partially be at fault.
On another note, from what I understand the JL 12W7 can handle 1000watts RMS, at the moment I am giving only 500. I cranked up the bass boost and signal strength on the amp to max, and use a separate bass knob up front to control the bass volume. Can this hurt my amplifier? I don't crank it too much on the knob, I just like having that ceiling for the songs that have quiet bass..
I'm not too worried about the woofer since I'm only at half power, and the amps do get a little cool air since I keep one seat down, although they still get pretty hot. The amps never went in to thermal shutdown yet. Any thoughts?
Thank you weltersys, you explained quite a bit of the things that were puzzling me, after messing with the placement I found the best place was on the far left right behind the seat facing to the rear of the car, the "clud" sound only appears when the volume is beyond any comfortable level now, looks like I figured out the biggest issue, placement placement placement....
Now I only hear (other than the sweet sweet bass) plastic rattle and some clanging on loud volumes, seems like the plastics rattle in the mid bass and the metal at a lower frequency, I also suspect you are right about the box hammering my trunk... The thing won't be attached till tomorrow and that may partially be at fault.
On another note, from what I understand the JL 12W7 can handle 1000watts RMS, at the moment I am giving only 500. I cranked up the bass boost and signal strength on the amp to max, and use a separate bass knob up front to control the bass volume. Can this hurt my amplifier? I don't crank it too much on the knob, I just like having that ceiling for the songs that have quiet bass..
I'm not too worried about the woofer since I'm only at half power, and the amps do get a little cool air since I keep one seat down, although they still get pretty hot. The amps never went in to thermal shutdown yet. Any thoughts?
Jl 12w7
Oh and the purpose of the mDF to the sides and in front of the woofer was to enclose the sound from the trunk and channel the sound straight into the cab. From what I read and hear for that to work the sub has to be sealed from the trunk and that wasn't done so that caused a lot of problems... So for any novices reading, don't try to channel your sound into the cabin through one of the seats, turns out it cancels out in this position and does not sound good at all, or loud for that matter.
Oh and the purpose of the mDF to the sides and in front of the woofer was to enclose the sound from the trunk and channel the sound straight into the cab. From what I read and hear for that to work the sub has to be sealed from the trunk and that wasn't done so that caused a lot of problems... So for any novices reading, don't try to channel your sound into the cabin through one of the seats, turns out it cancels out in this position and does not sound good at all, or loud for that matter.
Hi Aleksrussian,
After having read the description of your woes', it really doesn't sound like there's anything wrong with your driver (sub) at all. I use JL Audio amps and subs as well, and am fully aware of their capabilities.
What I think happened is: after swapping boxes (going from a tuned reflex to sealed), you noticed a radical drop in SPL; likely somewhere around 6 to 10db decrease in output...ask me how I know...!
To compensate, you increased the volume level at the H.U., problem solved, right? Ahhh, but...Problem NOT solved. It sounds like you're hitting the "Input stage" of the amp too hard; particularly on the kicks and strong (saturated) bass notes.
This is not the same thing as over driving the amplifier's output devices and causing them to exceed their 'safe operating area' (SOA) output level. When you allow the head unit to feed the amp's input stage too much voltage, it can sound exactly like there's something loose inside your speaker box; I did this when I changed my subs from 'bass reflex' to 'I.B.'!
I then performed a proper 'input sensitivity' adjustment and the problem went away. Here's a link to JL Audio's "amplifier set-up" web page...https://www.google.com/url?sa=t&rct...SeA9_VZVSl0urmTaA&sig2=F92ciTgNLP710E59gkthnQ
Hope this help's,
rigtec Cheers
After having read the description of your woes', it really doesn't sound like there's anything wrong with your driver (sub) at all. I use JL Audio amps and subs as well, and am fully aware of their capabilities.
What I think happened is: after swapping boxes (going from a tuned reflex to sealed), you noticed a radical drop in SPL; likely somewhere around 6 to 10db decrease in output...ask me how I know...!
To compensate, you increased the volume level at the H.U., problem solved, right? Ahhh, but...Problem NOT solved. It sounds like you're hitting the "Input stage" of the amp too hard; particularly on the kicks and strong (saturated) bass notes.
This is not the same thing as over driving the amplifier's output devices and causing them to exceed their 'safe operating area' (SOA) output level. When you allow the head unit to feed the amp's input stage too much voltage, it can sound exactly like there's something loose inside your speaker box; I did this when I changed my subs from 'bass reflex' to 'I.B.'!
I then performed a proper 'input sensitivity' adjustment and the problem went away. Here's a link to JL Audio's "amplifier set-up" web page...https://www.google.com/url?sa=t&rct...SeA9_VZVSl0urmTaA&sig2=F92ciTgNLP710E59gkthnQ
Hope this help's,
rigtec Cheers
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Oh, I thought that this might be helpful as well; if you haven't gotten an answer to this question as of yet. Here's a link regarding "Poly-fill".
Doubling the cone surface area and adding 1.5 lbs/ cuft poly-fill...WOW!!!!!!
rigtec, best regards!
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