hi im trying to do a boot install. long story short everything is sorted except how to store the subs the car came with two 10" alpine type r's and they are currently sitting in a bog (that i thinks causing them to under-perform) anyway i want to mount them behind the rear seats so the speaker faces outwards in a nice neat carpeted box. one problem i am ****ing useless when it comes to this and have no idea of all the terminology, i was just wondering if someone could simply tell me how much space do they need in the enclosure and do i need to put breathing holes ect ect and what else to i have to factor in? any help is greatly appreciated thankyou.

You have to find the manual for the subs and it will tell you the sub size enclosure. Go and have a look at my build on my boot install you will see how i done mine but instead of mine facing out have yours facing to the back seats, and id suggest no holes/ports. My subs are 2x 12" clarions and they blow **** apart how i have my setup, very clear, very punchy and plenty of base.

cheers, there some good pics and a nice looking setup! whats the advantage of the speaker cone facing the seats though? because i love the look of opening a boot and bang, two subs in your face

Look to be honest i think people just put them facing that way so they can open the center rear seat and you can see the subs, but thats all wank factor to me personally. Genrally this is seen done on the VT's, VX's and all that. I got my ones facing out and i couldnt be any happier, vibrates the **** out of the car and if your in that back seat you get a full back message as well as piercing painful ears. If i were you id face them forward so when you open the boot you can see your subs instead of a boxed wall. You will be happy with them facing the back, although you may notice you will get more rattle with them facing the back, which then means you will need to solve where the rattle is coming from.

Subwoofers are non-directional, therefore it doesn't matter which way you have them...

^ Very true. Another thing to know guys, when speaker (subwoofer) manufacturers give recommended sizes for a enclosure suitable for a specific subwoofer, it is for the 'normal' way of installing one (ie cone facing OUT, positive wire to positive terminal, negative wire to negative terminal) HOWEVER, if you decide you want to have the cone facing IN to the enclosure, you should wire it like opposite (negative wire to positive terminal, positive wire to negative terminal). This is so that the driver (the sub) pushes or pulls at the correct time, otherwise it'll sound like ar$e

reverse fit is the coolest (untill you get sick of the extra weight in the rear stuffing up your handling and you bin the lot)

How would it reverse the polarity in your amp? And how would it half the effect of bass? And how would it 'blow' the protection mode? Yes your right about some amps having reverse polarity protection, some do some dont. However, my previous post wasnt exactly the complete truth. Yes, how you wire your subs does depend on whether they are inverted in the box or not. BUT it also depends on how many other speakers (including other subs) are/will be playing the same frequencies. (ie the Low Frequency of your door/parcel shelf speakers overlaps the highest frequency of your sub, and/or if you have more than one sub) if your main speakers overlap the freqency of the sub(s), then you'll want them all to be 'pushing' air out at the same time (otherwise they will be opposite and cancel each other out - meaning very little or no audible bass) - in this case you'd wire them normal (positive to positive). or if your running 2 subs, you'll want them to be pushing air out at the same time, so you'll want to wire them both the same. However I still stand by what I said about subwoofer manufacturer's recommended enclosure sizes - that they are for a sub mounted in a box with the cone facing out (normal) and wired positive to positive. Think about it - if you turn the sub around so the back of it is now facing out, (keeping the polarity the same), it is now using the boot of the car as its enclosure, because the amount air behind the sub (which was previously determined by the inside dimension of the box is now determined by the dimensions of your boot, so the effect of bass is reversed, which you don't want. sorry HTURBO not trying to have a go, I do think in some cases you would be right and me wrong, but I think the situation does vary from case to case (ie different brands/number of speakers/how the boot install is laid out etc etc what it comes down to is speakers being in/out of phase - really just a matter of testing it for your own application - if you play music (helps if you know the song quite well) thru some speakers you should be able to hear if they are out of phase (wrong polarity) as the song won't sound right (quite horrible actually ). just my 2c going by what I've read and learnt, I do understand others people will have varying experiences Some original photos have not been recovered yet.

Quote: Originally Posted by onetidyvl [View Post] cheers, there some good pics and a nice looking setup! whats the advantage of the speaker cone facing the seats though? because i love the look of opening a boot and bang, two subs in your face The best way to mount a sub is with the cone facing the boot, magnet facing the cabin. You will get more bass if it is able to bounce around in the boot, and rebound back into the cabin; rather then straight into the cabin. only problem is that u get more boot rattle. the only advangage of having a sub facing the cabin, is the look from inside.

Just do what i said and wire it up the normal way, how bout that? Problem Solved.

Agreed, my reverse mounts were wired normally and they sounded awesome

Sub will sound much better faced towards the rear of the car. There is some theory behind this but I would avoid loading the subs against the back seat if you want the best results. Nothing wrong with running sub inverted if you choose to do this, however you will need to reverse the polarity.

Quote: Originally Posted by HTURBO [View Post] OMFG There was nothing wrong with what I have stated. Simply you reverse the polarity of your wiring when inverting the sub magnet out. opposite polarity to when installed cone facing out. Inverted: positive wire to negative terminal on sub. Negative wire to Positive terminal on sub. ---------- Post added 02-07-10 at 19:51 ---------- Quote: Originally Posted by hturbo [View Post] i would not recommend reversing the polarity. It will eventually reverse the polarity in your amp and will cause your amp to overheat. Also it will half the effect of bass.(been there done that) some amps have a reverse polarity protection so it can't be done. When i was young i done the exact same thing to my kicker amp and blew the protection mode in it. In the end, had it repaired & lost 2 channels because half of the board was fried. lol Some original photos have not been recovered yet.

Dude, Im talking about an inverted woofer, Magnet out on show. If you leave your wire polarity the same configuration you would with the cone facing out the sub is pushing your pressure sound waves into the sub box? By turning the sub around (inverted) and reversing the polarity you are effectively doing the exact same thing as conventionally mounted cone face out with polarity positive to positive, negative to negative. Understand what I am saying? Amps polarity cannot be trained as you have states earlier. An amp is simply sending an ampified signal to a motor. depending on the polarity of that motor will depend on whether it pushes or pulls, very simple stuff. Amplifiers dont have protection mode for the polarity of the speaker outputs as you stated also, what I think you will find is the amp has polarity protection mode for incorrect power polarity connection.

LOL, air pressure, sound waves are result of displacement of air from the pushing and pulling of the speaker irelivant of what shape it is. When attempting to integrate a sub with your main speakers, you want the positive pressure wave from the sub to coincide with the positive pressure wave from the main speakers at the frequencies that they are both reproducing. To do this, and again I am commenting on an inverted sub as you have effectively turned the sub around you need to reverse the push pull actions of the cone area and this is done by reversing the polarity. Again, reversed polarity will have no effect what so ever on your amp and in NO WAY will it damage your amp. It is effectively doing the same purpose it was if your sub was facing conventional cone out. Job of amp push and pull the cone, doesnt matter which way the cone is facing. OMFG he says. Oh yeh Power polarity. When a nob puts the power wire in the earth and earth wire in the positive inputs of the amplifier. Although I havent done this myself it will **** most amplifiers, however there are some amps that will protect itself if this was to occur.

My brother and I both had 2x Boston Pro 12s in the same size box running on the same PG ZX450s, mine were magnets out and his were magnets in, both wired pos to pos and neg to neg and the two systems sounded the same

wow ive had no internet for 3 weeks and ive missed so much ok.... subwoofers work the same way inverted or normal way... they only move air and use a box to amplify the sound, it makes no difference if it moving in or out or if the box is in front or behind. so it wont use the boot as a box when inverted... the sub box will be ALMOST the same but when a manufacturer recomends a 2 cuft box normally... if you were to invert it you need to remove the speakers displacement (sub physical size) from the box size, so if displacemnt was .2 cuft you would make the box 1.8 cuft. this is why all subs have displacement in the specs. wiring subs in reverse polarity will not damage an amp and ive NEVER seen it happen.... it only controls wheather or not the sub pushes or pulls... in fact some amps now even have a 180degree switch which reverses the polarity in the amp. normally when i fit subs inverted i DO wire them in reverse but this depends on the car, position etc need to listen to it first and decide if it needs reversing. my 2 cents anyway Some original photos have not been recovered yet.

Quote: Originally Posted by HTURBO [View Post] At the end of the day. Try both ways. If your happy to have it in reverse polarity then be it. If not leave it normal. It entirely up to the listener what sounds best. Running subs in reverse polarity will loose bass to some extent. no it doesnt man..... and ive tested this with a termilab db meter at work subs invertered and normal same db's Some original photos have not been recovered yet.

not all subs have curved cones mate.... pioneer shallow mount sub etc they have a flat face.... wiring the sub in reverse just means it will push instead of pull man.... but still moves the same when it happens its just in reverse to the doof doof.... if the box is in the cab ie hatchback it could possibly be wired standardly but for a commodore where its in the boot it may need to be reverse wired as it would help minimise the delay from the boot reverberations. also tests have been done (by alpine, pioneer themselves) that a sub friing backwards in a car or boot is ALWAYS louder in db's but ovioulsy sounds different to the ear... this is to do with the soundwaves being loaded onto a surface and reproducing the sine wave on the way to the ear. i would never fit a sub in reverse in my car if it hampered the performance but it dosent.... the 4 tens in mine are going reverse mounted. i understand your logik about the xmax of the cone being larger on the forward throw then the in throw but they are virtually identical. a flat sub face moves the same amount of air as a fcurved one providing they are of equal size ie12" this is why the kicker solabaric are reonound for being louder as a square 12" cone has more surface area. but as you have said every system is different and its really upto the listener as to their preference.

HTURBO is wrong, most if not all speakers have the same amount of travel in each direction, meaning they will push the same amount of air either way. Reversing polarity (or phase) will make no difference at all to the amplifier. Maybe do a bit of reading on the technical aspects of how a speaker works.