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Discussion Starter #1
I know its a bit cheeky, but any chance of an assist, i am planning some ICE mods, and wondered if any body had got any plans for a sealed sub box suitable for a 10 or 12" sub. and if they would care to share some details of its shape and size. Thanx in advance..............
 

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this is just what im doin at the mo , i too am struggling with dimensions for box as im fitting 2 13" subs in enclosed box . what makes u go for encosed as ported will give more bass but not as much quality. also there is plenty of sites that give advice but it all conflicts a bit ,i was at k&m installs at weekend and they were saying face them into boot as to point to hatch as bass wavelengths are long and it bounces back giving it the extra room to perform sort of thing ive actually got my car stripped out (boot ) at mo to do some sound deadening but any new subs should come with dimension instructions mine does but only for bass reflex enclosures.
 
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i have always tended to go with sealed boxes, as it is the quality thing i am after, and as for the facing into the boot thing, also correct, it was tried both ways in my last car, and proved right, managed to prove my mate with a similar car wrong on that one, also sealed boxes are easier to make, as the porting technique can be quite tricky, position and size of port, etc, etc.
Have you done the Front speaker upgrade, if so, what used, and how installed, what Brands do you favour, and why, personally i like pioneer,the EOL head units look ace and sound great, as for speakers, its a matter of choice, but we are a bit limited in the brands available i guess.
 
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Oh, nearly forgot, the other main reason for sealed boxes, is because free air subs, when turned up to '11' have the ability to over stoke and cause themselves damage, in a sealed box, the 'bounce' on the trapped air, ensuring (as long as the box is the right size) they cant hit the carriage.
 

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focal subs and focal polykevlar components for front genesis compact 4 amp and in search for a large genesis amp for subs 400wrms each, going to do some door builds
 
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sounds like a project fletch........never tried door builds, a bit like to much hard work for me, as for piccys, will do, but i tend to like the idea of a stealth approach, you know, nothing on show, but plenty of very high quality sound when used, maybe some .wav files (haha).
 

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im a bit pi**ed off with how mines going at mo my instructions with subs only supply info for boxes for bass reflex enclosure and seem to recommend this type but dont want boomy boxes in car im wondering if itll damage subs if i doo do (ron ron) enlosed boxes nobody really wants to give advice (shops ) as i havent sourced from them ie proper ice shops think ill do another search on it later , i did find a good site in america that showed all sorts of enclosures and sizes for diff boxes some for under front seats if i find it again ill post link .
oh and went to price the amp i wanted the other day £1000 genesis monoblock ouch its gonna cost £100 just for the right cables!
 
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thats a double ouch, why do you need such power, a silly question you may think, but think about it, you can only go so loud before you start vibrating the interior apart, unless you are goiong to show the system at sound offs and the like, there are plenty of excellant brands to be had slightly lower down the scale.
 
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I prefer to listen to the engine than loud music in the car. Maybe the 16 valvers don't sound as nice as the antique 8 valvers wink

Marlon
 

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when i ordered the subs i was under the impression they were 300wrms and not the 400 so iwas gonna just have it there for those mad moments and now its gonna cost me in amps .oh and sound offs arent my thing at all i want it to be good for me only thats why im gonna soundproof it . wink
 
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that was the answer i was hoping for. the last thing we need to do is add our great car to the list of 'loud' stereo muppets, its all about sound quality, not volume. so yes i agree, the sound of the engine is great, but for those moments when you cant drive like you want to, it might be nice to hear the music like it should sound, not with the bass turned down, and all tinselly, its not a honda civic you know.
 

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fletch:
im a bit pi**ed off with how mines going at mo my instructions with subs only supply info for boxes for bass reflex enclosure and seem to recommend this type but dont want boomy boxes in car im wondering if itll damage subs if i doo do (ron ron) enlosed boxes...
You won't damage the subs by putting them in a sealed enclosure, but at the same time you won't get the best performance out of them. Do the instructions have the Thiele-Small parameters for the speakers? If so, it's not that hard to design and build an enclosure of your own.
 

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thanks for reply d it seems like you know what your talking about pity i dont ! i have a list of spec's for you on speaker dont know if you can work out what you mean from this?
cone 26cm
sd 530.93cmsquared
xmax 7.5,mm
fs 47.37 Hz
Qes 0.650
Qms 5.000
Qts 0.575
Vas 27.12liters
Res 25.38 ohms
Mms 164.80 g
Bl 15.78N/A
le 17.06mH
Re 3.3 ohms
max power 800w nominal rated power 400w sensitivity(2.83 v/1m)
then it shows you charts for dynamic bass and linear bass for 30 ,40, 50,60 liter boxes does this make any sense to you ? :eek:
 

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Going on the figures you've mentioned, I'd recommend a sealed enclsoure of 56.26 ltrs (1.99 cu ft). If you can buy one off the shelf, then fine. Otherwise, I would build one using 18mm MDF (make sure you wear a mask when cutting MDF!).

Make sure that all the seams are sealed, and check that the INERNAL volume is correct (remembering to subtract the volume of the driver itself).

The shape of the box isn't that important, but make sure that the driver is at least 30mm from any other surface, and that there is at least 60mm clear behind it.

Hope this helps!

Feel free to ask if you've any more questions. :)
 

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thanks alot its been doin my head in trying to sort this one out ,oh and by the way do you mean each (im asuming you do) and would you run them in parrallel as dont really understand that it gives twice the power what are you losing?
thanks again craig
 

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Yes, thats 56.26 ltrs each, so if you want both in one enclosure then thats 112.52 ltrs or 3.97 cu ft.

As to wether to run them in parallel, it depends on wether your amp is 2 ohm stable. If it is, it will state it clearly in the documentation and thats all well and good - if not, keep them in series or damage could result!

Oh, and make sure that the RMS power output from the amp into 2 ohms isn't greater than the RMS power rating of the driver....or it might let the smoke out!!!
 
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I still think that one of you lot should buy my nice Dragster Amp.

4 x 100w rms
bridgable and lots of other stuff.

As new, in the box etc.

£100, bargain at twice the price!

If you want any pics mail me or check this out -

Nice shiny amp

This shows the amp when it was in the wifes Punto.
 

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cant keep a good man down , D thanks again for info i think im gonna go for a genesis dual mono 2 ohm stable in parrallel it puts out 700wrms in this form the speakers are 400wrms each would in your opinion would this be under powering them ? and how come you know so much about all this? oh also (if youve got time and patients) what sound deadening do you recommend ive been looking at dynamat extreme and acumatt but they arnt cheap are they but dont want to false economise.
thank AGAIN craig
 

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Using a 700W amp with 2x400W drivers sounds fine, not under-powered at all!! I'd double-check that these are both RMS, not PMPO or Peak or some other strange rating that often appears on sound equipment. For instance, if the amp is 700W RMS and the drivers are 400W peak, then methinks your drivers won't last long...

I haven't used Dynamat before, but have heard good things about it in the past. Apparently it's best to whack it on any large panels, such as floor, doors and the roof.

As to why I happen to know a bit about this subject...well, I design electrical & electronic systems for simulators for a living, and they have included some 'impressive' audio setups - my favourite included 32 tweeters, 12 mid-range and 8 sub-woofers, powered by 2kW of amps (not including the external PA system - that's another story!) in a sim the size of a mini-bus!
 
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