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YOUR RESEARCH996 Under seat subwoofer in the ”tub”?
Reported or suspected cause
simply the volume
Reported cause
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Reported cause
The problem is simply the volume, which is far too small.
Leading evidence: 'simply the volume' (1 discussions report identifying this cause; no attributable repair resolution). Across 1 matching discussions, the most frequently mentioned possible cause is 'simply the volume' (1 discussions; 1 report identifying it and 0 suggest it). The most frequently discussed action is 'Adjust level of bass output' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Install behind the rear seat bench above the control units
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Performed · outcome unconfirmed
I've now got the Bose subwoofer, which is installed behind the rear seat bench above the control units.
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Performed · outcome unconfirmed
I removed the Tang Band W5 woofers today and installed ETON 13cm subwoofers.
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Performed · outcome unconfirmed
I replaced the front door loudspeakers with old Focal Polyglass woofers and built the large enclosures into the door and insulated them with aluminum butyl.
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I've also replaced the standard dash and rear speakers with Alpine speakers of the same size.
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Performed · outcome unconfirmed
I replaced the front door loudspeakers with old Focal Polyglass woofers and built the large enclosures into the door and insulated them with aluminum butyl.
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11 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
911uk: 1 discussions
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Generation: 20261026T212127Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
Im thinking about mounting an under-seat subwoofer box to improve my stereo system.
One place that came to mind is in the ”tub” underneath one of the front seats.
Has any one tried that location or has the dimensions?
Not sure if there'd be enough room for a sub to be effective under the seat.
My Turbo has a sub box from the factory behind the rear seats and works very well. Could build one for there, or find an original one?
Other thoughts, has your car got speakers in the front doors, if not adding them with the speaker enclosures behind would help.
And lastly cabs can't have the rear shelf sub, so have one which fits in the passenger footwell
Pardon our interruption...
I have a coupe with original door speakers and upgraded speakers in the dash and back seat.
I can measure the space next time Im at the car, but would ideally find the dimensions and if it fits, order it so it can be mounted at the same time
The DLS version Im looking at is 290x210x73mm so relatively small.
I have been doing car hi-fi for 30 years now. I have yet to find an under-seat subwoofer that has satisfied me in terms of sound. They all have the same problem, that it tickles the passenger's sphincter a little, but it simply lacks the fun that a subwoofer should provide in the low frequencies. The problem is simply the volume, which is far too small.
I've now got the Bose subwoofer, which is installed behind the rear seat bench above the control units. If you insulate the cabinet, replace the speaker chassis (Tang Band W5) and give it enough power with a new power amplifier, the result is not bad at all.
I replaced the front door loudspeakers with old Focal Polyglass woofers and built the large enclosures into the door and insulated them with aluminum butyl. The front system on the dashboard (Bose), the door loudspeakers and the subwoofer run via a separate 5-channel power amplifier.
I've tried all of the above to get a decent sound out of the Bose box and gave up. The porting is such that there is a massive spike at about 80Hz that you need a DSP to drive out. I think that if you've made the door enclosures larger they will be doing so much mid bass and reaching down that they will compensate for this perhaps? I put Audisons into my door enclosures but i think it was a mistake as they don't move enough air...
I tried measuring with the seat still in yesterday, so it was not 100%. Unfortunately the oval shape of the tub makes it too small for the unit in mind. The width is like 24-25cm, but it gets to small after about 26cm so Im lacking 2-3 cm. I will measure again with the seat removed to get some decent numbers I can trust.
I think its hard to chose wich route to take. Ideally I dont want to put in a big (heavy) enclosure and alter the space or design of the interiour. But I also know that these smaller units will not perform to any higher standard. I have a couple of boxes Ive used in the past, but they are 12" regular boxes, so they will offcourse never fit (but give the right sound quality and power).
Have you tried insulating the housing? It's hardly surprising that the unstable plastic produces a peak at 80Hz.
I removed the Tang Band W5 woofers today and installed ETON 13cm subwoofers. Tomorrow I will insulate the entire cabinet again with aluminum butyl.
I had an active Eton subwoofer here, from which I had removed the 2 speakers. The woofer wasn't very big, but it had a fairly low resonance frequency.
Of course, I would prefer to rebuild the cabinet and the port in exactly the same way and install it instead of the BOSE subwoofer, but I want to try it this way first.
I added a bit of insulation but I haven't changed the drivers - I put them in series and I stuffed the box with poly before giving up on it. I found an 8" solid box that someone had built which fits to the side against the wheel arch on the passenger side - I'm using that at the moment which is a huge improvement but obviously not as OEM look as I would like.
I bought a Pioneer
TS-WX130EA under seat sub and put it behind the rear seats of my C2 996, as I don't have a bose sub box there. It sounds excellent and gives a good thump of bass that was totally lacking before. Has an incline controller to adjust the level of bass output. I've also replaced the standard dash and rear speakers with Alpine speakers of the same size. Can recommend the sub box.
Ive been measuring and found that if I put 2-3mm washers under the seat mounts on the passenger side, some of the Pioneer units will fit under the seat (991 seats). The Pioneer TS-WX140DA have rounded corners so will probably go for that one.
Glad to hear that you are pleased with the result, the 140 unit should have similar performace.
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