attempting to get loud in the Aristo, with seats that don't fold...
plus a very restricted boot opening.
its assembled in the boot in 3 main pieces, that are then held together with 4 more pieces, plus a removable top, and baffle.
the problem is, it all started going downhill once testing began...
with about 70 litres sealed, and 200 litres tuned to 58Hz, I expected a peak around 50Hz....
tones tones tones, sweep, sweep, tone, tones tones.... it peaks at 36Hz.... 142dB at 36Hz.
so I moved the entire baffle up, reducing the ported chamber by a lot, and thereby increasing tuning, right? 130 litres, tuned to 70Hz?!?
tones, sweeps, etc....
141dB at 37Hz... my peak didn't move... wtf man!
plus a very restricted boot opening.
its assembled in the boot in 3 main pieces, that are then held together with 4 more pieces, plus a removable top, and baffle.
the problem is, it all started going downhill once testing began...
with about 70 litres sealed, and 200 litres tuned to 58Hz, I expected a peak around 50Hz....
tones tones tones, sweep, sweep, tone, tones tones.... it peaks at 36Hz.... 142dB at 36Hz.
so I moved the entire baffle up, reducing the ported chamber by a lot, and thereby increasing tuning, right? 130 litres, tuned to 70Hz?!?
tones, sweeps, etc....
141dB at 37Hz... my peak didn't move... wtf man!
Attachments
Originally I ran it with the stock rear shelf, so the stock subwoofer grill could go back on...
This was until I discovered that it gained SPL by simply duct taping the port to the shelf.. so I made a new shelf with a round over...
and also, decided to call myself "Team Duct Tape"
This was until I discovered that it gained SPL by simply duct taping the port to the shelf.. so I made a new shelf with a round over...
and also, decided to call myself "Team Duct Tape"
Attachments
double layer on the top, and some bolts, trying to reduce the horrible flex the box has! don't know if it'll increase my SPL, doesn't really matter as its intended as a musical box anyway 
silly me didn't round the internal end of the port before I assembled the box, and the router doesn't fit inside the box.
so, dremel, flap disc, and an orbital sander, and I ended up with this, not great, but it'll do.
also added some silicone sealant and duct tape alone some joins, and gasket foam along others. Added a second layer to the back of the box as well to reduce flex.
silly me didn't round the internal end of the port before I assembled the box, and the router doesn't fit inside the box.
so, dremel, flap disc, and an orbital sander, and I ended up with this, not great, but it'll do.
also added some silicone sealant and duct tape alone some joins, and gasket foam along others. Added a second layer to the back of the box as well to reduce flex.
Attachments
it did, but with the 70 litre sealed chamber it has now, the sealed chamber has a resonant frequency of about 65Hz
dB drag rules.
doors closed, measured on the windscreen, engine not running.
two batteries, one in the stock location, one in the rear.
i just ran several simulations, the port length is dominating the volume changes. about 20cm should tune the box to 65Hz. strange though, I've never tried these changes and seen the port hold tuning this way...
could be the resonance frequency of the car air space... i'm baffled
no pun intended
could be the resonance frequency of the car air space... i'm baffled
no pun intended
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its fine, I've come to accept that 36Hz is where its at...
plus, the reinforcing, duct tape, and rounded port really did help...
higher.wmv - YouTube
plus, the reinforcing, duct tape, and rounded port really did help...
higher.wmv - YouTube
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