thats usually distortion, might be from the box tuned too low if its a ported box or too much power making it over excurse? lol is that a word? but yea that happened to me once and no its wouldnt be the make of the box thats doing that, its probably the amp or the tuning of the box...
what kind of sub and amp are they if i may ask? my brother let me use his boss amp til i had enuf for my bp1200.1 and i got a high pitched distortion from my sub when it reached lower frequencies
Anonymous
Posted on
i was wondering, how do you tune a box?
jay amaro
Unregistered guest
Posted on
that depends on what type of box: SEALED which a sealed box doesnt offer much tuning except by 2 ways that i know of which is enclosure size and using polyfill or fiberglass (insulation) added inside the box and then while its not exactly tuning you can adjust the location and direction the subwoofer/woofer fires and try to get a gain but using the area surrounding it i.e. pillar, corner, glass etc. for example if you had a sealed sub firing straight into a rear seat you might get a better bass responce simply by turning the box around or vice versa you just hae to use the vehicles natural acoustics which is different for all cars. thats about it for sealed there isnt much you can do. PORTED now for ported you have a great deal more choices as in addition to placement you can also adjust by port length and size to tune it at any given frequency within its range. BANDPASS a very poor choice all the way around but within a very limited range it can be tuned for very high spl but you will need very carfully selected crossover points to catch the roll off and hope your woofer, midbass of other sub can give you some badly needed "fill" to reproduce the frequency ranges not covered before or after where the bandpass is tuned. sealed and ported tend to be more linear and accurate. jay
Anonymous
Posted on
my sub is an L5 12's solobaric.... my amp is a JBL BP600.1....
the sub sounds funny with any amp i put on it....i think its the box....an sealed 1.1 cu ft plywood one.
what i originally asked is......is there a noticable sound difference in a plywood box and an MDF one???
jay amaro
Unregistered guest
Posted on
as for the plywood question yes it can be a suitable material if it is a hardwood versus a softwood species plywood and also the grade of plywood used and if you do use it you need a -
grade A face and a grade 1 back 7 ply sheet but considering the price of that (around 45-60) to mdf's price and i would save that type of plywood for furniture, cabinets and stuff like that. id trade you mdf or soft plywoods all day long for a good grade A1 hard plywood!! i love to make custom cabinets and tables!
also even better than MDF which is just what it says a Medium Density Fiberboard i hear all this talk about plywood, MDF, 3/4" and 3/4" bonded and doubled or using a 1" MDF and particleboard, fiberglass etc etc. particleboard just simply sucks and should be turned back into sawdust it is the worst wood product ever invented. mdf is good if its braced properly because it does and will flex. a high quality hradwood faced plywood is good and about as equal to mdf. if your really serious and thickness should be determined by enclosure size, subwoofer size and when i built something that i really dont want to resonate much i use HDF!! it doesnt get much better than that but i go an extra step as for lining the interior of the box that i am not willing to share at the moment but you want a material that is stiff and will not flex which can be controlled by bracing, material choice and thickness. if anyone tells you an exact material and thickness to use they are lying to you and they know very little about physics.
**anonymous** oh yeah i forgot to tell you some things about using fill for a sealed box to try and "tune" it well first a few general rules of thumb apply which is reserve a pound of fill material per cu ft. then start adding a little fill 1/4 to 1/2 pound at a time to change the responce and stop and listen each time until it gets where you want it. leave it loose theres no need or benefit to attach it to the inside of the box. you can add and adjust by filling the box with anywhere from 10% to 75% fill. another neat trick with sealed boxes and using fill well first of all sealed boxes are always smaller than the other types but you can even go smaller than the minimum recommended enclosure size and use about 50% fill to make the box act larger for the subwoofer so if not sound quality but size is real critical then sealed and using fill would be a good idea. jay
Anonymous
Posted on
ok....i have a 1.1 cu ft sealed box made of 3/4" plywood (mahagany). will my solobaric sound better in a 3/4" MDF box of the same size???
will there be any sound difference???
Anonymous
Posted on
im starting to understand a little more about tuning, but when i hear about tuning a box to 32 hz, how is that accomplished?
jay amaro
Unregistered guest
Posted on
if the box is braced properly and "stuffed" to be honest i doubt there will be a very noticeable sound difference. the ping type sound you mention does seem like a backwave reverberation or possibly a loose panel. im curious how did you make the box? did you use screws or nails? is the box sealed good? did you use any type of glue or adhesive between the joints and did you use a butt or a mitered joint to put the box together? if you answered nails, no glue, no sealant/chaulking then i would take the box apart and glue each panel connection and fasten them with course thread screws. use something like gorilla glue which is a polyuerethane wood glue or i personally like liquid nails subfloor adhesive and when i use it to join a box in addition to screws i dont need to caulk the inside since it is sealed also. but then again its not a bad idea to caulk the inside for good measure if you want some extra security. also you will want to attach braces either cross braces (tie the sides, top and back of the box together) or a ribbing type brace that runs from front to back which for a 1 cu ft box just one down the ctr of each side should be fine in 1x1 or 1x2. and also did you use cleats? i put cleats at every joint connection which is also glued and screwed when i assemble the box. that gives me 3 attaching points for each panel connection. then id add a little stuffing and let me know if you still have a problem but i would think there shouldnt be anymore. it sounds like you have a loose panel connection in the box to me though. your gonna loose internal volume and with the displacement of the subwoofer and assuming you have adequate bracing (to the joint connections and box)id say you are gonna lose between .15 to .20 cu ft. im just guessing though and you can do the math for the exact displacement. jay
Anonymous
Posted on
i'm gonna build a new box , and use MDF this time..
the one i have is chaulked and was put togetther w/ glue and nails....im gonna use screws and stuff this time....and brace hte crap out of it!!!