Loudspeaker enclosure advice please
Discussion
A strange place to post this but it really is relevant.
I am going to install a reasonably good audio system in my Aeon and have bought a pair of 6.5" Audiobahn component speakers with crossovers and tweeters. They are rated at 280W (gonna need some power to hear them above the V6
)
I can just about squeeze them into the side panels in front of the driver & passenger but unless I build an enclosure of some type behind the speakers they will..
a) Get all the road dirt thrown up from the front wheels
b) Sound awful in the free air
So I was wondering if any of you guys have any idea what size of enclosure I should build to house these beauties between the inner skin and the outer fibreglass sills. I will have to make it from sheet alloy and stuff it with acoustic wadding but should it be ported?
Any advice is greatly appreciated
I am going to install a reasonably good audio system in my Aeon and have bought a pair of 6.5" Audiobahn component speakers with crossovers and tweeters. They are rated at 280W (gonna need some power to hear them above the V6
) I can just about squeeze them into the side panels in front of the driver & passenger but unless I build an enclosure of some type behind the speakers they will..
a) Get all the road dirt thrown up from the front wheels
b) Sound awful in the free air
So I was wondering if any of you guys have any idea what size of enclosure I should build to house these beauties between the inner skin and the outer fibreglass sills. I will have to make it from sheet alloy and stuff it with acoustic wadding but should it be ported?
Any advice is greatly appreciated
You do realise with those componants you'll need an amp to drive them? The head unit won't provide enought power.
As for enclosures, the tweeters don't need one and should me mounted as high as possible and pointing into the centre of the car. A good place is on the dash.
The woofers are best suited low down. A common solution is to build enclosures in the foot wells for them. They don't need to be sealed like some sub-woofers, but do benefit from a solid mounting location for optimum base. Stuffing wadding behind them is a good idea, and I'd get some Dynamat sound proofing behind them too.
If you want the full monty, then you'll be wanting a proper subwoofer too. You can get nice small ones now (down to 5" I think) so can be mounted under the seats.
Then there's speaker wiring, amp wiring etc........
As for enclosures, the tweeters don't need one and should me mounted as high as possible and pointing into the centre of the car. A good place is on the dash.
The woofers are best suited low down. A common solution is to build enclosures in the foot wells for them. They don't need to be sealed like some sub-woofers, but do benefit from a solid mounting location for optimum base. Stuffing wadding behind them is a good idea, and I'd get some Dynamat sound proofing behind them too.
If you want the full monty, then you'll be wanting a proper subwoofer too. You can get nice small ones now (down to 5" I think) so can be mounted under the seats.
Then there's speaker wiring, amp wiring etc........
I was hoping that the head unit (at 50W x 4) would give me half a chance with these but if I have to I will find a teeny amp to put in there somewhere. The tweeters will go on the dash nicely (probably surface mounted) As for subs under the seats ... that's a non starter as I had to go an inch BELOW the existing floor level (on a kind of steel 'under bulge') to get enough headroom! My bum will be the lowest thing on the car However I might be able to make a small sub enclosure behind the seats but I will have to see how much room there is when I've trimmed the interior.
My main question is still unanswered though - how big do I have to make the box enclosures to get a reasonable sound?
However I might be able to make a small sub enclosure behind the seats but I will have to see how much room there is when I've trimmed the interior. My main question is still unanswered though - how big do I have to make the box enclosures to get a reasonable sound?
The speakers don't need to be enclosed, as such. There is no disadvantage to having the rear of a cone in 'free air', in fact it is an advantage to sound quality - Providing the sound produced by the rear of the cone is shielded from the listener.
The ideal enclosure for any speaker is 'as big as possible'. Especially if you want bass. Speaker enclosures are just to shield the sound from the back of the driver from the listener, as it combines with the sound from the front and causes cancellation and a washed out sound.
Some enclosures are 'tuned' or 'ported'. This is basically just reflecting the sound from the back of the driver, at just the right distance so the sounds don't cancel but combine at a specific frequency. Its usually just a trick to beef up the bass from a fairly substandard driver.
For true quality, don't enclose it. Just shield it from crap and stuff a bit of rockwool sound deadening around it.
edited to say:
Also, aluminium sheet is an exremely resonant material, not suited to speaker enclosure or mounting, it would sound well rough. Wood is almost always used. If you could do something to damp the aluminium panel that the speakers are mounting into, it would help. Perhaps contact adhere material to the back of it. If you flick the panel with your finger, and the sound it makes rings for more than a quarter of a second - then its not going to sound too good with a bass speaker mounted to it.
>> Edited by feet on Wednesday 12th January 01:14
The ideal enclosure for any speaker is 'as big as possible'. Especially if you want bass. Speaker enclosures are just to shield the sound from the back of the driver from the listener, as it combines with the sound from the front and causes cancellation and a washed out sound.
Some enclosures are 'tuned' or 'ported'. This is basically just reflecting the sound from the back of the driver, at just the right distance so the sounds don't cancel but combine at a specific frequency. Its usually just a trick to beef up the bass from a fairly substandard driver.
For true quality, don't enclose it. Just shield it from crap and stuff a bit of rockwool sound deadening around it.
edited to say:
Also, aluminium sheet is an exremely resonant material, not suited to speaker enclosure or mounting, it would sound well rough. Wood is almost always used. If you could do something to damp the aluminium panel that the speakers are mounting into, it would help. Perhaps contact adhere material to the back of it. If you flick the panel with your finger, and the sound it makes rings for more than a quarter of a second - then its not going to sound too good with a bass speaker mounted to it.
>> Edited by feet on Wednesday 12th January 01:14
As already mentioned, woofers don't need to be sealed like some sub-woofers, but do benefit from a solid mounting location for optimum base. MDF is a good material to use, but won't like getting wet. GRP can also be used if you make it thick enough so that it doesn't deform when pushed. The most important thing with woofers is that they have a solid mounting location.
Regarding power, maufacturers often quote max power as opposed to RMS. Take a look at the RMS rating of your speakers and find an amp that outputs the same (or even more) RMS power than time. You are far more likely to damage the speakers from under powering them than over powering them! If you crank up your head unit it will distort the speakers and can damage them.
>> Edited by KITT on Wednesday 12th January 09:29
Regarding power, maufacturers often quote max power as opposed to RMS. Take a look at the RMS rating of your speakers and find an amp that outputs the same (or even more) RMS power than time. You are far more likely to damage the speakers from under powering them than over powering them! If you crank up your head unit it will distort the speakers and can damage them.
>> Edited by KITT on Wednesday 12th January 09:29
There will be an optimum size for the enclosures based on the characteristics of the cones. If you pump a lot of power into a cone that's moving in free air all you'll get is a damaged voice coil and handly any volume.
Have a look in your local Maplin shop, they will have a cheap (£5) book on speaker design probably Babani or similar. The enclosure will make far more difference to the sound volume and quality than almost the choice of driver, it's critical you get an enclosure. Most car doors are roughly speaking, an enclosure, they leak air but on the whole they do act as a crude enclosure, especially if you're fitting large speakers.
Sub speakers will be crap without an enclosure, pointless. (Like a sub on a hatchback parcel shelf, nothing below 100Hz and it sounds more like a wobble board than a speaker) An enclosure can be a tube, some of the best subs I've heard in cars were basically a ported tube with a cone at one end, even a smallish bass driver, say 8", will give reasonable sound in this configuration although not at "competition" sound levels.
Have a look in your local Maplin shop, they will have a cheap (£5) book on speaker design probably Babani or similar. The enclosure will make far more difference to the sound volume and quality than almost the choice of driver, it's critical you get an enclosure. Most car doors are roughly speaking, an enclosure, they leak air but on the whole they do act as a crude enclosure, especially if you're fitting large speakers.
Sub speakers will be crap without an enclosure, pointless. (Like a sub on a hatchback parcel shelf, nothing below 100Hz and it sounds more like a wobble board than a speaker) An enclosure can be a tube, some of the best subs I've heard in cars were basically a ported tube with a cone at one end, even a smallish bass driver, say 8", will give reasonable sound in this configuration although not at "competition" sound levels.
Thanks for the input guys.
I think I will construct an alloy sheet 'pod' to bond to the back of my inner body side skin - this will seal it completely against water ingress. I will then reinforce the mounting surface with some MDF, line it with Dynamat and stuff with acoustic wadding to make the most of the acoustic quality. The pods should be about 300mm x 200mm x 200mm (equivalent to a small car door maybe?) and although the results will not exactly be Hi-Fi it will probably suffice. If bass response is not enough I will then look at installing a small pair of 6" subs behind the seats in an mdf enclosure.
I think I will construct an alloy sheet 'pod' to bond to the back of my inner body side skin - this will seal it completely against water ingress. I will then reinforce the mounting surface with some MDF, line it with Dynamat and stuff with acoustic wadding to make the most of the acoustic quality. The pods should be about 300mm x 200mm x 200mm (equivalent to a small car door maybe?) and although the results will not exactly be Hi-Fi it will probably suffice. If bass response is not enough I will then look at installing a small pair of 6" subs behind the seats in an mdf enclosure.
Like busa_rush said: there's an optimal size for every speaker. If you want to know the best volume for a box for your speaker, visit the tech-support section on the audiobahn site: www.audiobahninc.com Look for the Thiele parameters.
If you don't have a lot of room to work with in the car, you could try moulding something in place with cloth/epoxy or glassfiber. I generally use small glassfiber patching kits for this, which are available in most DIY stores overe here in The Netherlands.
>> Edited by ElCamino on Monday 17th January 08:58
If you don't have a lot of room to work with in the car, you could try moulding something in place with cloth/epoxy or glassfiber. I generally use small glassfiber patching kits for this, which are available in most DIY stores overe here in The Netherlands.
>> Edited by ElCamino on Monday 17th January 08:58
ElCamino said:
visit the tech-support section on the audiobahn site: www.audiobahninc.com Look for the Thiele parameters.
Thanks for the link - I'll have a peek
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