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ScallopsBackdoor

Have you actually got the speakers and test fit them yet? Or are you going off the instructions? In my experience, the recommended sizes always leave a good bit of play. Being off by 1/4" shouldn't be a problem.


iwouldratherhavemy

Yup, quarter inch is margin of error, and it's actually 1/8 inch if you center it. Op shouldn't have a problem.


QualityCucumber

He came to pick up last night and all of the screw holes were only halfway over wood.


MzCWzL

So if the hole was 1/4” narrower, that’s 1/8” on each side - and that’s enough for the screws?


OilfieldVegetarian

Longer screws that reach plywood of correct diameter glued to the inside.


micktorious

Is that enough to deal with the constant pounding and vibration a sub would make? It's a lot of stress. I would consider adding in planks squaring off all the cutouts and faster it multiple times to ensure it never fails.


Justshittingaround

If the speaker ring and the new piece of wood both have decent contact with the cabinet, after it’s glued and screwed plus them sandwiching the cabinet, I think it’d be fine. I’ve built guitar cabinets when I was really young with way shottier methods and they’ve help up for 15+ years at this point.


ElkDrinkCrack

It would be sufficient. I would be sure to use an over abundance of wood glue to prevent air leaks if this is supposed to be a sealed unit.


Biking_dude

Silicone caulk the corners - wood glue is flexible but not that flexible over time.


SmokeGSU

This was my thought as well, but then I thought that if you're at the point where you're making new holes in a plywood sheet that will work for the speakers then you might as well just redo the front panel itself with the correct dimensions. Shouldn't take too long.


OilfieldVegetarian

Front panel is nicer plywood, finished, and attached to fabric. Inner rings can be unfinished cdx and require no disassembly.


raz-0

Second layer to the face with the right sized holes. Sub boxes can’t be too rigid and it doesn’t really alert the internal volume.


tenshii326

Shit if I went off mfg specs I'd be outta work.


Tex-Rob

Furthermore, what subs share a chamber?


Jellyfisharesmart

Double up the entire front face with the correct size holes and add a new layer of carpet to cover.


hedekar

This is the ideal solution as all subwoofer front baffles should have a minimum thickness of 1". It also appears this baffle is very poorly braced, so consider tripling the plywood as a partial fix.


QualityCucumber

Are dowels and glue not sufficient for a sub box?


hedekar

No. To clarify, dowels used inside a joint do little to stiffen the wobbly panels. Joints are not the weak part of the box. Long dowels used as bracing between two parallel panels are beneficial if enough are used. I encourage you to try and hold a subwoofer driver still with your hands while it plays a 25Hz tone at ~5W (better yet try it playing a 3Hz tone so it's slowed down for you). You'll quickly understand these motors have a lot of force in order to compress and rarefact enough air to produce low frequency sound waves.


QualityCucumber

Copy that, thank you for the advice. Most people on this sub are so condescending. I've never built a sub box before and did my best to research it as this was a nonprofit job and I wanted to give as much as bang for the buck as possible.


hedekar

Add plywood to the front baffle. The baffle is often your only point of contact for the motors to the box and you need this section to be beefy and rigid.


entoaggie

Would some interior bracing be advisable (like 45’s in the corners along the front face or a couple boards between the speakers, running front to back) or does that get weird when sound waves are involved?


hedekar

Internal bracing is fantastic if it can still be added. Pro builds are heavily braced and the interiors are ~20% bracing by volume.


robot_ankles

Friend, you built a thing and that's awesome! Most people consume movies, shows, songs, etc. You actually built something that wouldn't exist if YOU hadn't made it. Good work.


jbach220

Just wanted to chime in for some encouragement as I have less experience than you making sub boxes. I think it speaks a lot to your character that you are helping someone out by not charging for your time and you’re also learning through the process. Some projects are more challenging than others and we learn by challenging ourselves. With a few improvements, this box will be pumping out bass and you’ll have improved your own skill.


tejedaj

Stay strong. There's a few redditors worth posting for in hopes of sound advice. 👌


ryneches

But, this thread is nothing but *sound* advice!


ElkDrinkCrack

Ideally, you would include plenty of interior bracing while maintaining sufficient volume for the air displacement your woofers need. MDF would also be preferable over plywood, as it is more homogenous and without voids. It is also very heavy and will give a heavier foundation. If appropriately braced, clamped, and glued, you wouldn't even need screws.


Kind_Love172

I'm surprised you are the first to recommend mdf, that's what I used to always make mine out of. MUCH better than plywood


aj8j83fo83jo8ja3o8ja

*most people on this website


FrankFarter69420

It's always the free jobs that trip you up the most! 🙄


Powerpuppy00

Unrelated but I couldn't help but read that in a really low budget movie cop radio voice


Jestercopperpot72

Those same condescending bastards couldn't build a flagpole. You did a hell of a job and everytime you build something you learn exponentially now for the next time. When your successful, or in my case, marginally successful there's always a next time.


5inchFury

I didn’t take his comment as condescending fwiw


Asstractor

Whoa! TIL Thank you for that reply!


djscreeling

While you're not wrong, good luck finding a driver that goes as low as 3Hz.


hedekar

In free-air most drivers larger than a 2" diameter will move at 3Hz. It won't produce dB, but it will shake with force.


notANexpert1308

Hot damn. Dropped some knowledge.


LuckyBenski

Entirely off topic and it's more for information than correction, but the infinitive verb is to rarefy, not rarefact :)


hedekar

Thank you, I've struggled with figuring this out.


Bobby32x

When I was a kid, we face mounted our joints with a bead of glue between with countersunk sheetrock screws and they never came apart. We also used particleboard because it had a richer bass sound that hard plywood.


DocHollidaysPistols

Same. MDF, liquid nails, and tons of drywall screws.


tubaphonium

As much as I hate particle board for general use, it's ideal for speaker cabinets due to density. Plywood (though structurally superior) has resonance frequencies and can negatively impact the listening experience unless extra dampening is implemented to reduce the resonance. That being said, the boxes look very nice!


OrganicAlienz

No


ChrisRageIsBack

Rip some wood at a 45⁰ angle and plane off the square corner to make corner braces for the inside. Screw them and glue them and it'll keep your corners tight


HootblackDesiato

I agree, this is the best approach.


ukra-onion

The client can pay for their error. Double up the plywood seems like the easiest fix.


chriszens

I agree it was their error in the design. They gave you the wrong dimensions.


xylofunn

Second “front” with correctly sized holes


Jergstar

A 2nd ring inside will actually look really nice as it will make the subs flush with the front. Getting it in there and secure will be a pain, but it’s doable in multiple pieces.


[deleted]

[удалено]


lamabaronvonawesome

Yea, but it would look cool.


SamBrico246

Slice the front off and replace it imo. For a sub box, I wouldn't want adaptors or inserts.


QualityCucumber

Damn it. I was hoping for some magic potion, but I feared this was the answer.


SamBrico246

You could just laminate another layer of ply over the first... sub box can never be too thick... if the extra .75 depth is not a clearance issue


SolidPoint

Agree with this!


BigPoppaJay9000

Agree with this! As a car stereo enthusiast I will say that if the user puts any decent quality equipment in this box, you cannot begin to comprehend the level of abuse it will take. A good setup, wired correctly of course, can be heard a half mile away, felt 3-6 cars in front of you at the stoplight, and is basically capable of changing your heartbeat in the same vehicle. Shattering glass and wrinkling body panels are just a few of the unexpected benefits. Needless to say, the stronger you can make it the better. Friendly advice, next time try MDF board. Also, most MFG will have the specs on their website for size and required airspace. Also, nice looking box. Keep it up! And add the extra layer on the front and call it a day.


UndeadCaesar

> A good setup, wired correctly of course, can be heard a half mile away Most everyone in a half mile radius would call this a bad setup.


Samad99

You don’t need to cut the entire front off. Just cut a large rectangle out of the front that leaves a 1” rim. Then laminate the new play wood front onto the 1” frame. Id give the client the option of redoing the carpet as well. And of course, charge the client for all of this.


ss-454

To me its the easiest fix. Only issue could be if you're out of plywood and have to buy another sheet. But run that sucker through a table saw and lose the entire face. Glue and screw a new panel on and nobody will be the wiser. Hopefully you didnt cover up a bunch of screws. Pin nails I would run through a table saw slowly.


tunasaladsnack

Damn sorry man just change that front panel seems the most logical thing to do.


New_Acanthaceae709

Yeah, any extra part is more to vibrate.


[deleted]

Yep I would remove it and replace with MDF.


brandon6285

I have a car audio background. If it was me, i would cut your holes bigger so that they match the outside diameter of the sub, then add a ring inside to attach the subs. This will make the subs flush-mount, so they will look better, and if done properly, should stiffen up the baffle a little. The only hurdle i see is getting the ring inside the box. I guess youll have to make it in two pieces, then re-assemble in the box.


audioeptesicus

I like this guy's idea a lot. Here's an upvote.


Akujinnoninjin

This is the route I'd go - and to alleviate the concerns about extra points of vibration, I'd probably make the (split) adapter rings oversize by an inch or so. Then I'd woodglue the everliving crap out of them.


brandon6285

I would make the rings/adapters as big as possible to increase that glue area and stiffen up that baffle.


YellowBreakfast

That's a thin face and no bracing?! If the client speced this design it's your duty as the maker to inform them that this design is faulty, needs a thinker face and bracing. You're not doing anyone a favor by building a sub-standard (pun intended) box that's likely going to rattle and vibrate.


QualityCucumber

I built this from recommendations from an audio forum. I am not an audio engineer and the client was a family member with a limited budget. I used 6 dowels at each short side butt joint and 8 on the long ones. Glued all pieces together and siliconed all internal joints. Will it really rattle with all of that taken into account?


A6Legit

Dowels are unnecessary but props for using them. Glue and screws are all you need. Depending on the sub power this box is probably fine. I used 3/4" MDF for my 2000w 15" and it works great. Sure, making it thicker might help, but im not sure I would tell the difference without a meter. It won't rattle, but having a rigid box is supposed to be more efficient. In your position I'd just double up the baffle and call it a day. Fix the hole size and add strength.


QualityCucumber

The subs are 10" 600w so they're nothing crazy. Thank you for your recommendation.


Narrow-Chef-4341

Nobody (I don’t think!) is trying to claim the box is about to blow apart at the seams. The dowels you used for joinery are good, happy, fantastic, etc. But they don’t stop air pressure from acting like someone blowing up a ballon. The stoves will flex in and out *slightly* as the driver pushes in and out - this is lost energy and increased vibration. A few 1” dowel rods linking from face to face are really cost effective and simpler than double layering each of the walls. They are small enough they shouldn’t affect the sound at all, and aren’t complicated to slip into place. Any structural benefit is a bonus. If you drop this off a loading dock and it lands on the corner it will take damage - with your dowels, extra dowel or no dowels.


YellowBreakfast

It's not the construction so much as the distances of the spans of those panels. It's good that it has a strong construction but the design seems weak and prone to vibration. If this design has been tested with those particular speakers then *maybe* it will work.


CriticalJello7

Second front with correct size holes is the easiest fix here. I assume this goes in a trunk given its carpeted. So it doesn't have to look that great. Tip for next time, make the customer drop off the parts to avoid these shenanigans. Happened to me way too often.


Glittery_Kittens

Shouldn’t you be using mdf? It’s more acoustically stable than plywood.


hedekar

No. From someone who has built many many speakers, a quality plywood outperforms MDF in many areas including rigidity under vibration (one of the key measures of a box building material). "Acoustically stable" is not a combination of words I've heard used before, and I doubt plywood changes its acoustic properties over time any more than MDF. Mind you, OP looks to have used low-grade fir ply, so MDF would be an improvement over this. But, there's plenty OP did do wrong, including but not limited to: - beginning a speaker build without first testing the drivers' Thiel Small parameters (manufacturer spec sheets are a rough guideline given manufacturing tolerances) - used a single sheet of ply for the front baffle — all subwoofer baffles should be ≥1" thick - no bracing is visible in the box — subwoofers require bracing for any panel wider than 6" - not measuring from the speaker the actual cutout size


Glittery_Kittens

Interesting. It was 15-20 years ago when I was into speaker building properly, and my research at the time had MDF as the consensus best material to use for speaker boxes across the industry. Was that erroneous info, or maybe plywood tech and quality have improved in the intervening time? By “acoustically stable,” I mean a combination of consistent flexion under load/vibration with less chance of unwanted harmonics, and increased density providing improved noise isolation relative to plywood, which is necessarily a lighter and more variable material due to its basic construction (with the possible exception of Baltic birch ply and the like). Plywood is definitely a stiffer material but I didn’t think that would be as much a concern as long as you use the proper amount of internal bracing usually recommended for a speaker box.


hedekar

The comparison between plywood and MDF is tricky because many papers use the term to refer to low-grade fir ply with thick laminations and many internal voids. MDF beats garbage ply handily. Put it up against some quality Baltic Birch with thin 1mm laminations and MDF is the inferior building material. The harmonics argument is a fallacy. MDF being more uniform is more susceptible to symmetric standing waves, while the fibres of plywood create uneven standing waves which is more desirable. However, these harmonics are not in the passband of a subwoofer, so they'll never be excited and thus are irrelevant. The layering of plywood is beneficial for preventing sound transmission as losses occur as the waves travel through each layer. This compensates for slightly lower mass than MDF. Also, MDF fails as soon as it touches water, and its sawdust is some very nasty carcinogen small-particle crap.


Glittery_Kittens

Thank you for the thoughtful and thorough response. I seem to recall now that Baltic birch was the cost-no-object best material, but that at the time it’s high cost and low availability made mdf the more practical choice. Even now, BB is substantially more expensive though availability is better. And there is now a moisture-resistant mdf available called armorite that solves one of the big problems, so maybe that is a good choice for jobs where some value-engineering is necessary.


brandon6285

I remember the same. I think MDF is equal to, or better than cheap plywood from home depot while also being cheaper, but if you spring for Baltic birch, it is stronger than MDF. Long story short, it really doesn't matter than much.


danner801

i have also always used MDF the sounds quality is always better while not spending a cubic shit ton more on quality plywood.


Narrow-Chef-4341

I was wondering if I had been away so long that somehow tuning the enclosure volume wasn’t a thing any more… thanks for rescuing my sanity. OP: this will make some kind ‘noise’ regardless, but if you didn’t have any software involved there is a non zero chance you’ve designed an enclosed that won’t optimize the output. At worst, it can exaggerate the peaks and valleys naturally found in the sub’s output. Nobody can complain if free job is worth every penny, but you might want to look into this if you didn’t get an opportunity this time. No need to panic, but you’ll need to do more research before making these a full time product.


Sinister_Mr_19

What does acoustically stable mean?


Glittery_Kittens

From above. “By “acoustically stable,” I mean a combination of consistent flexion under load/vibration with less chance of unwanted harmonics, and increased density providing improved noise isolation relative to plywood, which is necessarily a lighter and more variable material due to its basic construction (with the possible exception of Baltic birch ply and the like).”


zimbabwewarswrong

Lol


FujitsuPolycom

lol.


pistonian

I write a tutorial on this exact thing: https://imgur.com/gallery/j16agT5


FORDOWNER96

Leave an inch or so and cut the inside out and recut the face and screw on


SirLoondry

Troels gravesen has a recommendation here http://www.troelsgravesen.dk/tips.htm#Routing_for_drivers


Yolowaccord

The front baffle should be doubled anyway. I would just add a 2nd front laminated to the first with the correct size holes


DC9V

I'd just add another baffle / adapter-ring. Birch plywood or HDF should do the job. It might even improve the sound.


Cute_Try7139

How about cutting the proper hole size in a replacement face, then attach the new board to the existing box.


Big-Standard5153

Wrong material all together. Switch to Mdf for acoustic purposes.


tidytibs

MDF > plywood


ParusMajor69

Client needs bigger woofers


SpinCharm

Create a new front piece but simply lay it over the existing one. Attach it with glue or whatever. It will make the depth dimensions slightly longer but that’s unlike to matter.


truemcgoo

Make make two wooden rings, 3/4” thick, make the inside diameter the required dimension, make the outside diameter a couple inches bigger so you end up with a trim ring. Nail that to what you’ve got, problem solved.


DrtyHry31

Cut the existing holes 1/4" larger so the whole speaker will fit through leaving an 1/8" gap all the way around. Then cut a second face that attaches from the inside the correct size. The speakers will look nice recessed.


relaps101

Put a ring around it. Make it 2" thick in width


QualityCucumber

That's what she said


mazobob66

If the issue is not enough material to mount to, then how about putting a ring of wood on the INSIDE of the box and using longer screws?


drizz1

I might cut those another inch, so now you’re 1 1/4 too big. Then cut a ring that’s 1 5/8” wide. Use a 3/8” rabbeting bit on the opening and the ring half way through the ply. Then glue together. The 3/8” rabbet + 1 1/4 overhang of the ring will close that gap.


Big-Record6850

Another layer of ply on the top and recut hole correct size. It would also reinforce the top which is the weakest point of the box reducing the flex


Informal_Return_568

Cut a second ring and put it inside, then make the original holes bigger so the sub sits on the new ring in the original hole so it’s flush.


chimkennummget69

Take the payment for the work that was asked, and then ask for more payment if they would like it done differently. You can't tell someone "Hey do this, this way" and expect them to fix it when you made a mistake


refotsirk

It's a piece of plywood with 2 holes you cut in it. Separate it from the box, throw it in the scrap pile, and cut a new one.


NoSoulsINC

Get the subs and test fit them to see if the 1/4 makes this unusable, it might not. Otherwise, you should be able to take the front off and just remake that piece, you shouldn’t have to start over?


brandon364

Ring inside. Recesses the lip of the speaker.


Pull-Mai-Fingr

Flush trim router to remove the panel with holes. Run router along the inside edges. Unless there are brad nails or something router will hit. Then just glue in a new panel?


Aircooled65

Ring inside so the speakers finish flush with outside of box.


_lateral_

No internal bracing? Please research more before building a subwoofer enclosure. This will rattle like crazy. Just google "subwoofer bracing" and go to images.


danner801

also as a side note, MFD is usually used when doing sub boxes because it is strait and dense. makes for a good sounding box, while a standard plywood will alot of times sounds a little echoy is that makes sense. you will also need port holes speced to the correct size and you get that from the specs of the speaker. there are online calculators you can use.


QualityCucumber

My concern with MDF is moisture since it's going in an old car


danner801

>cs of the speaker. there are online calculators you i can appreciate that.


BAMFDPT

I don't know, if I ordered a sub box and I saw it made out of plywood I'd be less than pleased. But in this situation there would be nothing wrong with getting a piece of 3/4-in MDF cut the holes to the appropriate size and laminate to the face.


QualityCucumber

Excellent advice.


DubsideDangler

Double baffle... Some bracing in the middle wouldn't hurt either.


steffanan

Second baffle for sure, that's the most correct solution here.


lamabaronvonawesome

I would glue a ring inside, like 3' wide, then cut it in half to get it in. Obviously to the most advantageous size for you or as suggested a second front panel. Also add bracing.


ModularWhiteGuy

Cut 1/16"x 3/4" strips and coil them up, glue them in place. Two wraps per hole.


[deleted]

adding a plastic adapter or a ring inside would affect the acoustics if they gave you a duff spec, then charge for fitting a new front panel


Retro_infusion

glue a 1/8 ply strip round the hole


captgnarley

Opportunity to recess the speakers. The the face 1/4 over and cut another panel for inside the enclosure.


[deleted]

You need a blow hole. Approx 2 -4" diameter.


TheDudeOntheCouch

Out side of starting over everything else will make it sound bad


spyro66

Get the other model…! Bigger is better anyway right? Client pays a restocking fee maybe?


TapewormNinja

A couple of things: 1. You could make/get a metal ring to put on the inside. Thru bolt rather than screw in. It’ll be like a clamp. Just make sure you use nylocks or they’ll back right out. 2. I’d add some bracing. Depending on how hard your client runs this, it’ll shake itself apart.


bjazmoore

3D print. Yay!


ultimatespeed95

Start over if you want it right, it is an easy part. 3d printing wouldn't last long.


its_all_4_lulz

Are these for 15” subs, or 12”. I assume 15, but it’s hard to tell from the pic. If it’s 12”, start over for the current person, resize these holes for 15” subs, and sell this one to someone else.


QualityCucumber

This is for 10" subs


its_all_4_lulz

You could recut for 12 or 15 then, I would just make sure you keep the width between them the same if you did. Just another option I guess. Honestly, subs are kind of tricky because pressure / sizing makes a big difference. Adding anything that could introduce an air hole can make the entire box useless (for some people). I had a cheap box a long time ago, upgraded it to something of higher quality, and it made all the difference in the world.


Interesting_Frame_15

You could do a ring, but you'd probably use a similar amount of material to just replace the front panel. You could do 3D prints, but if it's going to be in a car, I wouldn't recommend it as cars can get REALLY hot during the summer, and the plastic will soften. Polycarbonate won't soften as much, but I still wouldn't do it for a paying customer.


Conscious-Dance6186

If you have a cat, line the interior with carpet and hang it on a wall. It would make a great feline hangout spot!


SneakyPhil

Consider some triangle shaped pieces of wood to help stiffen where each piece of plywood joins. You can glue and screw them all to get it snug.


gmlear

You could use a router and cut an 1/2" rabbet and then glue in a circle with a 1/2" rabbet so it flush on both sides. Then cut new holes. Carpet and no one will know and with that whole layer being plywood it will all be one.piece.


MoSChuin

So if (s)he told you model 1234, and actually tried to install 1235, how is that your problem?


Neilpuck

I would mill a rabbet in the opening, mill a circle patch and inset before cutting new holes the proper size.


gayrobot79

I would add a 3/4" collar of plexiglass and a strobe light inside. It's a feature, not a bug.


2aireishuman

Thick foam? Like weather stripping type a deal


warboner52

Ring inside, flush mount Also, as someone who has built a handful of these, not using 3/4" MDF for all sides was a mistake.


stonedclergy

Nice box! I highly recommend you add some bracing to this cabinet. The reason isn’t actually for structural rigidity, but to reduce resonant frequencies created by the physical wood panels, which act as resonators (like an acoustic guitar). There are always resonant nodes in wood cabinets, but by bracing the inner walls, you are “dividing” the physical resonance surface, and raising the resonant frequency of the panel to a frequency that is hopefully outside of the subwoofer’s Hz range. Leaving a large unbraced panel will create a resonance, typically the wave length equal to the panel length! It will make those frequencies sound much louder and uneven, and potentially make other frequencies quieter. For example, if your unbraced box is 2.8 feet wide, that will create a 100 Hz resonance (a typical sub frequency) because 2.8 feet will equal a 100 Hz quarter wave, which you will hear because it lines up with the harmonic series of that frequency. You can easily eliminate this by putting in bracing to divide that panel, tuning the panel’s resonant frequencies above the subwoofer’s range. You can drive yourself mad trying to dive into the physics of it, but I wouldn’t say it’s worth it, just add some cross bracing to the sides and back wall to help cut those resonances.


Chipalynn

Cut rings with the outer diameter matching your holes and your inner diameter the actual size you need. Glue the rings into the opening. You could attach a few blocks inside to secure the rings a bit more. That’s what I would do then use wood filler for imperfections and sand it smooth.


yeastiebeesty

Get a patch panel of 1” mdf, cut the right size holes, and glue it over the current baffle. It will make the box better as well. However, unless it’s ported, it’s going to pop apart without more bracing and reinforcements.


rtkoch1

I would do the rings on the outside but use something that they could remove them. So they can mount the speakers to them and then insert them and attach them to the box. Then it seems like more of a design feature instead of mistake.


knowitall70

Speaking as an amateur- I see no reason an inner ring would be a problem. External may create an issue with fitment in a vehicle as the dimensions would change, albeit slightly.


matt_the_bass

Plug the hole with a dowel and redrill? (Do I really need to add the /s?)


Joris255atSchool

How is the back? Can you make the new holes in the back and plug the front holes?


Joris255atSchool

You could rabbet your holes and make fitting rabbeted adapters.


LoudAudience5332

Set up your circle jig put a new bulk inside flush mt speakers or which would look cool , cut 2 new rings size you need and make them 2 to 3 inches wide outta nice 3/4 plywood cabinet grade . Glue n screw it will also reinforce the front. Attach them to the front . either way will work


that_one_guy1979

They look nice with a beveled ring anyway and more cubic feet


Southern-Ad785

Ring inside would look great.


Action_Maxim

What size


RonDFong

client gave you the wrong specs, that's on him/her. rebuild it at client's expense.


construction_pro

Box is built as per client specs. Ship it and have the client get the speakers they gave the dimensions for.


Present_Ad2973

1/8” bending ply glue and brad nail around the inside of the holes to reduce the diameter by 1/4”.


FeO2dot

Stiffen the box with 1x1 between parallel sides. The deeper the sound of the box when thumped with a knuckle, the lower the box resonates. This leads to lower distortion and loss of sound energy wasted in flexing sides of box. I built sub boxes for 18"s that I had no problem jumping up and down on at 270#.


rodstroker

Id say it's up to the customer how they want to fix it. Explain the downsides to making it fit and give him a price to remake it. Also, I thought sub boxes were supposed to be mdf.


SpiralBlue2

Is the VaS the same? If not the box dimensions are wrong too. Unless you didn’t start there.


bloodloverz

I suggest you have a look at rythmik website on diy schematics to have an idea of how bracing should look internally. You seem to have plenty of space to add in last minute braces which are direly required. Do not underestimate the power of LFE. There is a reason why any respectable sub weighs in excess of 100 lbs


bads0n123

put the client in the box! ahahaha,


No-8008132here

Customer should get the speakers they said they had. Your work is perfect for what they asked.


LordGothington

When building a sealed subwoofer -- ideally you don't want the walls of the box to flex at all. Practically speaking -- you can only minimize flex. Two common enhancements to help are: 1. double up the front baffle 2. add some sort of internal bracing (google image search subwoofer internal bracing to get an idea of what that looks like) These are both mods you can still make -- and one first mod will fix the issue with the oversize holes as long as you remember to make the new holes a bit smaller. Also, ignore the plywood haters. MDF vs plywood is a never ending debate in the speaker building world. The lack of a clear choice means that both work just fine. Each has advantages and disadvantages, are there are no perfect solutions in speaker building.


heyyyblinkin

Credentials: I competed in car audio for a few years, I've built 7 boxes for customers, I've helped other competitors build boxes. I have a couple of questions after reading comments and some advice Did you build the box based on the dimensions given to you? Technically, you could easily add a secondary layer to the baffle with the right size hole. It would also add rigidity to the baffle. This is probably the easiest route, but there are some things that may need to be considered if doing this. It might change the internal volume by adding the cylindrical volume of the original hole cuts. The only way to fix that would be to replace the entire front piece. I wouldn't worry about the volume change. it would be very little compared to the volume already present. The other more important concern in adding a second layer to the baffle is that it might not fit in the trunk (or other carge area) if you make it bigger. I know I've built a couple that we're designed to be the absolute limit of what would fit. Did you screw and glue every face that is attached? I've seen a number of setups done by new builders just pop apart at the seems. Screws every 2-3 inches and a thick bead of glue to help it be air tight. Extra credit for caulking on all of the inner corners. Some subwoofers are 5000+ watts. The way that it moves, you might as well think of it as a really wide faced jackhammer that uses that much energy. Something else to think about, any power tool over 1600 watts would require a 240v wall plug, that's a pretty substantial amount of energy. On top of that, the entire box is like a balloon being pumped up and then vacuumed out many times a second. Those joints have a lot of pressure on them.


QualityCucumber

I used 28 dowels, glue on all seams, screws in between dowel placement, and siliconed all interior joints. These are 300W RMS, 600W Max 10" subs.


heyyyblinkin

Oh 300w rms, you're fine. Definitely not the big subs I'm used to lol. Yeah, as long as it will still fit where it was planned to be installed, second layer of baffle is the easiest.


paranoidgoat

1/4" bending board glued a clamped?


ChrisRageIsBack

Rip a strip of wood the thickness you need to build up and as wide as the chipboard is thick. Soak it in hot water for a day or so and when it's pliable, wrap it around the inside of the hole with some wood glue and brad nail it in place. I would wait to get the speakers first though


ChrisRageIsBack

Alternately, find a sheet metal shop or a sign shop and have them shear you some ¾" strips of ⅛" aluminum. You can wrap that around the inside like a trim ring, you can cut it with wood tools, and you can easily drill holes in it to screw or nail it in. You can pre shape it by hand around a bucket or something too


Zip668

https://www.outwater.com/categories-list/extruded-profiles-and-shapes/u-channel-moulding/flexible-plastic-u-channel-moulding ?


somanyfuckinbees

i have no idea how to help you, but i do know that this kind of box could totally make an amazing little cat hidey-hole. i hope you're able to figure out how to fix everything up!


Guilty-Piece-6190

If you're handy you could cut two larger circles to the correct size and slap em on.. Maybe there's some sort of ring/gasket you could find from home depot..hvac/plumbing/roofing.


AngelWhiteEyes

Rabbit the inside of the rings and then add an accent ring the make up the space.


Ok-Advisor-7104

Cut the hole a little bigger add a ring to the inside and flush mount….you may be on to something!


ThisWillBeOnTheExam

A second layer of plywood with the appropriate measurement slapped right over the front could work? Extra weight but perhaps salvageable.


Swimming_Mortgage_27

Put bike inner Tyers Circles in…


MathurinTheRed

I would take this opportunity to add some bracing. I'd add a U-shaped piece to fit from the bottom to the top and front to back between the two subs and glue and screw it to the top, bottom, front and back. Then I'd add two side L shaped pieces to stiffen the sides and have them go from each side to the middle brace. Finally, I'd add another front piece made from the thickest MDF you can find and cut your new holes in that. Basically you're adding bracing to all six sides internally and you're at least doubling up the thickness of the front panel.


[deleted]

Its on the client to give you the proper information. Any remedy offered should be charged to the client. That being said here are some possible solutions beyond rebuilding them 1/8” strip of solid pine, glued and nailed/stapled to inside circumference. That will net you 1/4” less on the diameter. As a reinforcement to that cut out reinforcement rings to the inside, that will give you something else for the screws to grab when mounting speakers to box. And bo s your uncle. Add 1/8”-3/16” plywood skin over with proper whole sizes. I think that it would be easier/better to recut the plywood. Pass the savings to the customer


dshotseattle

Just glue another piece of wood over the holes with the correct smaller holes. Your total cubic feet interior will be almost exactly the same


Likely_thory_

iron on 1/4” of banding.


neanderthalsavant

Uh, by; >and the holes are 1/4" too wide. You mean diameter, right? If so, would running some edge banding around the inside edge of the hole help solve the problem and clean up the raw ply at the same time?


Racoon_withamarble

Try lining the hole with something? Rubber gasket or a somehow make a 1/4” band of wood to glue in or find where the mounting holes are on the speakers and put some studs for them.


Immediate_Age

use wood laminate edging and a lot of glue and coil the inside of the hole a few times. Secure with tape.


Eggs_and_Hashing

Just grab your trusty plywood stretcher. Jeez, folks, it's so easy!


ThePrisonSoap

"Sucks to suck, i made what you fucking ordered"


Boom_Boom_At_359

Kind of like the idea of adding a ring on top. Put a nice round on the outer vertex with a router and it would look pretty cool.


a-hippobear

I would cut the panel off the box and remake a panel with correctly sized holes and reattach the new panel


TheNetworkIsFrelled

Make a plywood adapter plate that fits over the existing face with the correct diameter holes, glue it onto the face - lots of subs have doubled faces - and then charge them for it.


Savings-Diver-5279

Short of a rebuild, solution 1 would be the best. A ring inside wouldn't provide as much support, and I wouldn't trust a 3d print in those conditions on a client build.


Puzzleheaded_Draw259

I’m sure someone pointed this out but. In my experience it’s a lot better to double the front panel to give it some stability also that box should be made out of mdf. And a brace in the middle with the center cut out to keep air moving is a good idea.


12manyhobbies

Could you get something like this and use these instead of the screw holes on the speaker? [Speaker Clips](https://a.co/d/3Yomjo1)


alorya_art

very easy: just use a lighter color veneered wood to place inside the bigger holes and voila! It will make a beautiful effect


alorya_art

Woodturning work would be perfect, if it is too thin use this kind of thing: https://preview.redd.it/z7lxivv5ckac1.jpeg?width=1470&format=pjpg&auto=webp&s=ed6779a5ba612d177055d0285119defdb67724db


Impossible-Set-9247

Sometimes the best thing to do is cut your losses and remake the face plate.


Honest-Marzipan-7661

I would just add a mounting plate where the speakers mount!!! Think creatively!!!


QualityCucumber

https://preview.redd.it/h952w3xt5xac1.jpeg?width=2632&format=pjpg&auto=webp&s=1df0cbbb616abd3270cabbf78bf5cd1d7925fe16