That's very specific, only the hard core serious competition 180 db guys do that.
The vids you see on youtube are not those guys, all those vehicles should still be street legal unless they blasted the windsheild out.
I don't know the details of how they use concrete lining, I just know they do.
The vids you see on youtube are not those guys, all those vehicles should still be street legal unless they blasted the windsheild out.
I don't know the details of how they use concrete lining, I just know they do.
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no no no. This is not for a competition, this is not to be the loudest going down the street. obviously I understand I won't be able to hear the difference and that is not the point.
Simply asked what was your guys's experience with lining enclosures, surely you don't just let them sit as unsealed mdf.
If i'm going to spend several hours constructing a purely sq enclosure, i'd love to extract that extra decibel.
You buy a rolls royce because it's the equivalent of an sq car, but wouldn't you expect it to be fast as well?
I'm mostly settled on using fiber glass and resin on the inside to seal, add integrity, and make it smooth. Has anyone tried this and found a difference?
Simply asked what was your guys's experience with lining enclosures, surely you don't just let them sit as unsealed mdf.
If i'm going to spend several hours constructing a purely sq enclosure, i'd love to extract that extra decibel.
You buy a rolls royce because it's the equivalent of an sq car, but wouldn't you expect it to be fast as well?
I'm mostly settled on using fiber glass and resin on the inside to seal, add integrity, and make it smooth. Has anyone tried this and found a difference?
Some people around here paint enclosure interiors but that's mostly for moisture barrier and aesthetics. Like I said, most people don't worry about smoothing the inside of enclosures.
Fibreglass can be used to seal and smooth but it won't add any integrity (other than the aforementioned moisture barrier and aesthetics).
Integrity (the kind of integrity I believe you are looking for) comes from strength and stiffness and as such mdf is a very poor foundation. Painting or wallpapering the interior with vinyl isn't going to do much. I already told you how to get that last db. Do you have any bracing in your box? If not that will give way more benefit than making the interior smooth.
For reference, I'm going to start a car audio build next week, I'm getting a free beater car to play with. I'm going to make it loud by using plenty of driver (pair of 12 inch Kicker L7) and plenty of amp (1000 watt class d monoblock amp with 120 amp fuse) - $300 worth of kijiji junk I picked up last year.
I'm going to use enclosure design to get the highest spl possible (with 30 hz tuning), the box is going to be large (might even build it inside the trunk so it can be as large as possible and not worry about having to try to cram it through the trunkhole). The box is going to be strong, stiff and well braced. No mdf.
I'm going to use oversized ports, probably with large flares on both ends.
I'm going to upgrade the big 3 (alternator to battery, battery to chassis, engine ground to chassis). I might even add another battery.
To be honest, the LAST thing in the world I'm worried about is making the box interior smooth to gain a fraction of a db.
This whole system (including the car) is going to cost less than $500 and I predict it will shame much prettier, costlier, and complicated systems in much higher classes.
I've got a friend that recently picked up a Honda CRX with an IB wall with eight 12's and over 2500 watts rms worth of very expensive amps. I'm pretty excited to blow that right out of the water with good design on a shoestring budget with a tiny fraction of his drivers and power.
Fibreglass can be used to seal and smooth but it won't add any integrity (other than the aforementioned moisture barrier and aesthetics).
Integrity (the kind of integrity I believe you are looking for) comes from strength and stiffness and as such mdf is a very poor foundation. Painting or wallpapering the interior with vinyl isn't going to do much. I already told you how to get that last db. Do you have any bracing in your box? If not that will give way more benefit than making the interior smooth.
For reference, I'm going to start a car audio build next week, I'm getting a free beater car to play with. I'm going to make it loud by using plenty of driver (pair of 12 inch Kicker L7) and plenty of amp (1000 watt class d monoblock amp with 120 amp fuse) - $300 worth of kijiji junk I picked up last year.
I'm going to use enclosure design to get the highest spl possible (with 30 hz tuning), the box is going to be large (might even build it inside the trunk so it can be as large as possible and not worry about having to try to cram it through the trunkhole). The box is going to be strong, stiff and well braced. No mdf.
I'm going to use oversized ports, probably with large flares on both ends.
I'm going to upgrade the big 3 (alternator to battery, battery to chassis, engine ground to chassis). I might even add another battery.
To be honest, the LAST thing in the world I'm worried about is making the box interior smooth to gain a fraction of a db.
This whole system (including the car) is going to cost less than $500 and I predict it will shame much prettier, costlier, and complicated systems in much higher classes.
I've got a friend that recently picked up a Honda CRX with an IB wall with eight 12's and over 2500 watts rms worth of very expensive amps. I'm pretty excited to blow that right out of the water with good design on a shoestring budget with a tiny fraction of his drivers and power.
I'm pretty excited to blow that right out of the water with good design on a shoestring budget with a tiny fraction of his drivers and power.[/QUOTE said:
@Just a guy:
doing things like the big three (might gain you a few fractions of a db)
why would you flare the ports if you aren't worried about those extra db's?
you'll add another battery? the guy on I posted a link to added an extra battery, do you know how much he gained?
about as much as oh wait, lining the inside of his enclosure.
doing things like the big three (might gain you a few fractions of a db)
why would you flare the ports if you aren't worried about those extra db's?
you'll add another battery? the guy on I posted a link to added an extra battery, do you know how much he gained?
about as much as oh wait, lining the inside of his enclosure.
I like standard 3/4" 5-ply birch because I think it's stiffer than baltic, but baltic is nicer to work with, and more expensive. Both are stiffer and lighter than MDF, far superior for subs.
what size / how much power would you run to an enclosure out of 3/4 birch? Just to compare to mdf. If I were to use 1" mdf for 3 ft3, would you use 3/4 birch?
I've always heard to use 13 ply over 5 or 7 ply... you find it works good?
I've always heard to use 13 ply over 5 or 7 ply... you find it works good?
Density is useless without strength and stiffness. Jello is extremely dense but doesn't have any strength or stiffness. Aluminum is very light but very strong and stiff for it's mass. Which do you think would make a better enclosure material? If you can afford baltic birch it's nice but for a budget build I'd use just about anything (even osb) instead of mdf. Especially in a car where weight matters (if you care about fuel efficiency).
Doing the big three can gain you anywhere from 0 to several db, depending on how bad the original situation is and how much power you intend to draw.
Oversized ports will reduce velocity tremendously. Large flares help with end termination. Both of these things will have much greater effect than smoothing, which will simply reduce your Reynolds number. Unless your port is extremely undersized or extremely long your Reynolds number isn't going to be high enough to make much difference anyway, so smoothing won't do much. Have you looked up Reynolds number yet?
Sarcasm is easy and fun, right? You seem to be basing all these opinions on the results one random guy on the internet shared in a thread where he didn't say much about his measurement conditions. A passing car can skew your results by a few db and so can moving the mic an inch. Or opening the window an inch, or sitting in the car when you measure.
There are things that you can do that will make your system better and stronger and there are things you can do that won't make much (if any) difference at all. If you are suggesting that lining the inside of your sub box with vinyl is better than upgrading your wiring and adding an extra battery, I'm not really sure what to say about that.
Are you at UWO? If so I'm about 1/2 hour away and if things go well in about a month I'll have a car you can actually experience (not just random internet postings) so you can judge whether I know what I'm talking about or not.
Doing the big three can gain you anywhere from 0 to several db, depending on how bad the original situation is and how much power you intend to draw.
Oversized ports will reduce velocity tremendously. Large flares help with end termination. Both of these things will have much greater effect than smoothing, which will simply reduce your Reynolds number. Unless your port is extremely undersized or extremely long your Reynolds number isn't going to be high enough to make much difference anyway, so smoothing won't do much. Have you looked up Reynolds number yet?
Sarcasm is easy and fun, right? You seem to be basing all these opinions on the results one random guy on the internet shared in a thread where he didn't say much about his measurement conditions. A passing car can skew your results by a few db and so can moving the mic an inch. Or opening the window an inch, or sitting in the car when you measure.
There are things that you can do that will make your system better and stronger and there are things you can do that won't make much (if any) difference at all. If you are suggesting that lining the inside of your sub box with vinyl is better than upgrading your wiring and adding an extra battery, I'm not really sure what to say about that.
Are you at UWO? If so I'm about 1/2 hour away and if things go well in about a month I'll have a car you can actually experience (not just random internet postings) so you can judge whether I know what I'm talking about or not.
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I'm definitely not going with mdf this build, the small box I have now is already way too heavy. Could you comment on how effective it is per thickness? With your 2 12's and 1000 watts what thickness would you use? Normally I'd use 1" thickness if I wanted it to be solid...
Hi all,
For anyone’s knowledge, even some of the most respected studio reference far/mid/near field systems, some of which that cost a small fortune and are build with the highest standards and best materials and are designed for the most critical ‘professional ears’ in the world , are made of quality MDF or HDF. Some of them spend decades of costly research in improving their materials to the finest. So just ask yourself, do you think if MDF was that bad they wouldn't use a better material like ply that only would raise the total price of a system by less than 1%?!
1.PMC
2.Adam Audio
3.Genelec
4.Dynaudio
For anyone’s knowledge, even some of the most respected studio reference far/mid/near field systems, some of which that cost a small fortune and are build with the highest standards and best materials and are designed for the most critical ‘professional ears’ in the world , are made of quality MDF or HDF. Some of them spend decades of costly research in improving their materials to the finest. So just ask yourself, do you think if MDF was that bad they wouldn't use a better material like ply that only would raise the total price of a system by less than 1%?!
1.PMC
2.Adam Audio
3.Genelec
4.Dynaudio
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I didn't click any of those links, but are any of them car audio subwoofers? Was the primary goal behind any of them to get the most spl with the least internal losses with the least possible weight? I'm guessing no.
Weight, strength, stiffness, and minimizing internal losses are the 4 things that mdf does worse than any other flat sheet material. Mdf has it's place but that place is not in the trunk of my car.
That's my opinion only, but I don't want a 700 pound box with bracing at every 6 inches in my trunk.
You like big horns, don't you? How many big horns have you made with mdf?
EDIT - I forgot about moisture resistance. Car trunks (especially older cars with rusty bottoms) can get really wet and the carpet holds the moisture forever. Mdf is the worst material you can get for sucking up moisture, swelling and falling apart.
Weight, strength, stiffness, and minimizing internal losses are the 4 things that mdf does worse than any other flat sheet material. Mdf has it's place but that place is not in the trunk of my car.
That's my opinion only, but I don't want a 700 pound box with bracing at every 6 inches in my trunk.
You like big horns, don't you? How many big horns have you made with mdf?
EDIT - I forgot about moisture resistance. Car trunks (especially older cars with rusty bottoms) can get really wet and the carpet holds the moisture forever. Mdf is the worst material you can get for sucking up moisture, swelling and falling apart.
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If you had clicked on the links you would have seen that none of them are car subwoofers.
Actually, I did click those links and I'm not all that impressed with those studio monitors. They seem more high end pro-audio hype and flash than anything. A transmisson line studio monitor....? Seriously?
Plywood is most widely used in pro audio, the vast majority of tops and subs use it. The only place MDF is used is in studio monitors, for the same reason it is used in home audio speakers. MDF is simply just too flexy and heavy for subs when compared to ply. People use MDF in subs because they don't know better, or it simply sells to "audiophiles" who don't know better.
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I know, that was an attempt to politely say those products have nothing at all to do with the topic at hand (you can tell by the brand names) so there's no reason to even look at them.
chances are good that some of your favorite films and music were mixed on those speakers.
ive got a pair of one of the lower priced adam speakers. the ribbon tweeters are a joy.
but id never never use them in a car or foh
Why in the world would you think 5 cross plys of softwood are stiffer than 13 cross plys or hardwood? Standard 5 ply "birch" is thin birch veneer w/ softwood plys. True Baltic Birch is all birch.
Edit: I've just searched on your posts and most of them are disrespectful, flames or baiting. Beat it.
I've taken 2'x4' panels side by side and flex tested them, just what was available in home depot, appeared to be high ply count baltic vs. normal 5-ply. 5-ply I checked was stiffer than the baltic in equivalent thickness. Maybe the reduced number of piles is stiffer, or actual thickness is more, or it is directional in its stiffness, and I was flexing it against the stiff direction. Poplar is nominally 20% softer and lighter than birch otherwise. YMMV.
The product is sold as "birch plywood", it's poplar core with a thin birch veneer. Columbia Forest C-3 grade commonly available at HD, $47 for a 3/4" sheet. Reasonable quailty, works good for subs, but certainly not as nice as baltic birch.
http://www.columbiaforestproducts.com/Content/Documents/Hardwood_Plywood_Core_Guide.pdf
http://www.fpl.fs.fed.us/documnts/fplgtr/fplgtr190/chapter_05.pdf
3/4 in. x 4 ft. x 8 ft. C-3 Whole Piece Birch Domestic Plywood-165921 at The Home Depot
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@Turbo dawg
You said you flex tested them and the 5 ply was stronger? Just wondering if you compared overall density and mass.. I can brace for strength, but i'm curious about vibration and density...
I was at HD today and their plys looked really good. I couldn't believe how heavy the mdf was in comparison.. Never using it again...
5 ply maple verse 5 ply ^^ birch plywood. or even the poplar fur?
I don't think I saw pure BB there, and certainly nothing in 13 ply. Could you make some recommendations for an extremely sturdy subwoofer enclosure?
You said you flex tested them and the 5 ply was stronger? Just wondering if you compared overall density and mass.. I can brace for strength, but i'm curious about vibration and density...
I was at HD today and their plys looked really good. I couldn't believe how heavy the mdf was in comparison.. Never using it again...
5 ply maple verse 5 ply ^^ birch plywood. or even the poplar fur?
I don't think I saw pure BB there, and certainly nothing in 13 ply. Could you make some recommendations for an extremely sturdy subwoofer enclosure?
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