i got an alpine ported sub enclosure at the mo it has a shitty 175 watt sub in it but i jst got a 1000w alpine, jst wonderin if it wud b better to use the enclosure or put the sub under the parcel shelf
cheers j
1000w alpine on parcel shelf/or inclosure
Moderator: martauto
Only a couple of questions but its quite a wide topic:
The only type of sub that suitable for parcel shelf mounting is one that is designed for use 'infinite baffle' - ie a really really large box. I doubt your sub is designed for this. Most subs available nowadays are designed for box mounting or "IB".
Secondly, its unlikely that your sub is going to sound its best in a generic ported box (although it will work).
The only type of sub that suitable for parcel shelf mounting is one that is designed for use 'infinite baffle' - ie a really really large box. I doubt your sub is designed for this. Most subs available nowadays are designed for box mounting or "IB".
Secondly, its unlikely that your sub is going to sound its best in a generic ported box (although it will work).
beemerboy
post up your sub model designation and we'll tell you if it's ib or not.
if your alpine sub is ib (infinite baffle) and you mount it directly to the shelf then you have to ensure it is sealed front to back to eliminate return waves - these are sound waves that make the journey from the front of the sub to the rear (or vice versa) and muddy the sound. (they make it sound crap basically) this means sealing the cabin from the boot by blocking all the holes. this can be done with mdf and high density foam or with some glassfibre work. if you travel this route you'll end up with a sub that will happily play slow bass notes accurately but won't go too loud or like quick bass very much. so - what do you tend to listen to? as this question becomes relevant.
alternatively a ported box for little money should be availble from alpine (via a dealers) that's deigned specifically for that sub model. this will work a whole lot better than a generic box. it is possible to use glassed in t-nuts to bolt this to the underside of the shelf - the sub then works in its ideal enclosure size with porting enabling it to work as efficiently as possible i.e. it will play louder and go lower. this is more work but doesn't involve sealing the boot from the cabin.
alternatively if you walk into a dealers with a tape measure and measure the alpine enclosure and port carefully and do some maths you can then create your own custom box that will fit your shelf area more accurately. this is loads of work but will turn out the best for your sub and car combination if you do it right.
easier than these however is to buy the alpine box and secure it in the boot facing the ski-hatch.
infinite baffle subs are cosidered by many to provide better sound quality than sealed enclosure units - but they don't play as loud before distorting. before fitting ib subs you need to be quite sure that sound quality is your thing and that you'll be happy without toooo much volume - although it won't be quiet! sound deadening also increases volume - use liberally!
to put this into perspective for you i ran 2 alpine ib subs on the underside of my shelf for around 18 months and they shook the car quite happily. evetually though i pulled them out and now run two sealed enclosure subs in a custom box under the shelf - but this was around 50-55 hours installation work.
paul
post up your sub model designation and we'll tell you if it's ib or not.
if your alpine sub is ib (infinite baffle) and you mount it directly to the shelf then you have to ensure it is sealed front to back to eliminate return waves - these are sound waves that make the journey from the front of the sub to the rear (or vice versa) and muddy the sound. (they make it sound crap basically) this means sealing the cabin from the boot by blocking all the holes. this can be done with mdf and high density foam or with some glassfibre work. if you travel this route you'll end up with a sub that will happily play slow bass notes accurately but won't go too loud or like quick bass very much. so - what do you tend to listen to? as this question becomes relevant.
alternatively a ported box for little money should be availble from alpine (via a dealers) that's deigned specifically for that sub model. this will work a whole lot better than a generic box. it is possible to use glassed in t-nuts to bolt this to the underside of the shelf - the sub then works in its ideal enclosure size with porting enabling it to work as efficiently as possible i.e. it will play louder and go lower. this is more work but doesn't involve sealing the boot from the cabin.
alternatively if you walk into a dealers with a tape measure and measure the alpine enclosure and port carefully and do some maths you can then create your own custom box that will fit your shelf area more accurately. this is loads of work but will turn out the best for your sub and car combination if you do it right.
easier than these however is to buy the alpine box and secure it in the boot facing the ski-hatch.
infinite baffle subs are cosidered by many to provide better sound quality than sealed enclosure units - but they don't play as loud before distorting. before fitting ib subs you need to be quite sure that sound quality is your thing and that you'll be happy without toooo much volume - although it won't be quiet! sound deadening also increases volume - use liberally!
to put this into perspective for you i ran 2 alpine ib subs on the underside of my shelf for around 18 months and they shook the car quite happily. evetually though i pulled them out and now run two sealed enclosure subs in a custom box under the shelf - but this was around 50-55 hours installation work.
paul
i saw a doctor and she gave me some pills....


swr-1040 : that's a sealed enclosure sub. it'll have to be put into an enclosure of the correct interior volume for it to work at its best. mounting it under the rear shelf without an enclosure it won't sound very good at all.
the up side however is that making a sealed enclosure for it is straight foward so long as you have access to a jigsaw, tape measure, drill etc and have some patience...
paul
the up side however is that making a sealed enclosure for it is straight foward so long as you have access to a jigsaw, tape measure, drill etc and have some patience...
paul
i saw a doctor and she gave me some pills....


If you have the Thiele-Small data on the sub (should come with it) then you can calculate the exact enclosure size from here:
http://www.carstereo.com/help/Articles.cfm?id=26
The only value you won't have is Qtc, you get to choose this one. There is a little bit of writing on that page about Qtc values, I built mine using 0.707 and it sounds lovely.
http://www.carstereo.com/help/Articles.cfm?id=26
The only value you won't have is Qtc, you get to choose this one. There is a little bit of writing on that page about Qtc values, I built mine using 0.707 and it sounds lovely.
'89 Touring - slightly rippled with a rusty underside
'94 e36 tree climber
'94 e36 tree climber
jordano
if you walk into a dealers and ask they should be able to tell you all you need to know.
paul
if you walk into a dealers and ask they should be able to tell you all you need to know.
paul
i saw a doctor and she gave me some pills....





