MDF vs Birch

[kkerley33]

Well, I know this debate may never be solved, but I had the ever present "Honey Do' list that was growing out of hand. I won 4 tickets to todays Cubs vs Reds game in Cincinnati so I sent my wife and her 3 sisters to the game.

That allowed me to nail down the Honey Do list and crank the La Scala's...

Anyways, I was looking at building a "matching" LS looking box to hold my components and possibly place a Mid and Tweeter in to use a Center Channel.

So after readin the threads about MDF vs Birch, I was curious what to use and the costs.

The arguements that I have heard are that MDF sounds better on the low end while the detractors have responded with Klipsch only made the change to save money.

Well after my "price research" I can guarantee that Klipsch is indeed saving money by using MDF. One poster earlier commented that MDF is almost as much as plywood. That post was correct...accept that is only for construction grade plywood.

When you step up to B2 Grade Birch Core Plywood (cabinet grade), its costs over $45.00 for a 3/4 x 4 x 8 sheet. Grade C2 (general core) with a Birch Veneer Runs $32.00.

A 1 inch x 4 x 8 sheet of MDF runs only 14.00 while a 1 inch by 4 x 8 sheet of MDF with Birch Veneer runs 21.00. As you can see, Klipsh is indeed saving over 50% on the "base section of the LS2's compared to using Birch Plywood. That said, the 3/4 inch Birch Plywood did not have the strength rating that the 1 inch MDF did, but the 3/4 inch MDF and 3/4 inch Birch plywood were almost identicle. 1 Inch Birch Plywood is not readily available and is quite expensive when I inquired about Special Order...and it must be ordered by the Flat.

So thats my comparison...at least based on Cost. Hope this sheds some light...and let the argument...begin again. LOL

BTW...The Cubs won, I got nearly half the list done and plenty of time to enjoy some music.

KAK

[Guest " "]

"Anyways, I was looking at building a "matching" LS looking box to hold my components and possibly place a Mid and Tweeter in to use a Center Channel."

great idea

I would recomend an ST-350 instead of the k-77 and the 511B instead of the K-400.

It's an urban legend that the MDF sounds better and cost the same.  Most of the folks who heard LaScala II's and attribute the improved bass to the MDF, have never heard LaScala's with AL-4 xovers.  

Anyone who builds cabs can attest to birchply, cab grade, being a pricey item...well worth the price.

MDF is easier to make look pretty, since it does not soak up as much paint as Birch ply, it's cheaper to paint.

[kkerley33]

Fritz,

I can attest to the paint thing. I also built a set of Roller Platforms to put the LS1's on. I bought a sheet of the pricey Cab Grade Birch Plywood, they had a damaged piece so it only cost me $20.00. I have used almost a pint of black paint and it is just soaking through. I haven't hit the Lacquer yet. I may just not use Lacquer since they are only going to be "wheels" anyways to save the floors.

When I get around to building the Center, I will let you know.

My thought is to take the readily available plans for LS boxes from the internet and cut the Hieght in half since I will not be using the low end anyways. That should leave enough room for my DVD player, dish box and integrated Amp to fit in the opening. I will leave the back open to improve airflow.

Question to you is, where do I aquire the Horn, Midrange Drive, Tweeter and crossover? Should I attach anything for the low-end such as a passive sub off to the side? I have 2 twelve inch passive sub boxes sitting in the attic.

Any thoughts?

KAK

[Chicago_Pete]

Cubs fan, translation: Wait till next year:)

[Guest " "]

kkerly33

Sounds like you have a plan.  

The parts you need are all over the place.   I, like many on the forum, have a small stash of them.

[theplummer]

Well, I know this debate may never be solved, but I had the ever present "Honey Do' list that was growing out of hand. I won 4 tickets to todays Cubs vs Reds game in Cincinnati so I sent my wife and her 3 sisters to the game.

That allowed me to nail down the Honey Do list and crank the La Scala's...

Anyways, I was looking at building a "matching" LS looking box to hold my components and possibly place a Mid and Tweeter in to use a Center Channel.

So after readin the threads about MDF vs Birch, I was curious what to use and the costs.

The arguements that I have heard are that MDF sounds better on the low end while the detractors have responded with Klipsch only made the change to save money.

Well after my "price research" I can guarantee that Klipsch is indeed saving money by using MDF. One poster earlier commented that MDF is almost as much as plywood. That post was correct...accept that is only for construction grade plywood.

When you step up to B2 Grade Birch Core Plywood (cabinet grade), its costs over $45.00 for a 3/4 x 4 x 8 sheet. Grade C2 (general core) with a Birch Veneer Runs $32.00.

A 1 inch x 4 x 8 sheet of MDF runs only 14.00 while a 1 inch by 4 x 8 sheet of MDF with Birch Veneer runs 21.00. As you can see, Klipsh is indeed saving over 50% on the "base section of the LS2's compared to using Birch Plywood. That said, the 3/4 inch Birch Plywood did not have the strength rating that the 1 inch MDF did, but the 3/4 inch MDF and 3/4 inch Birch plywood were almost identicle. 1 Inch Birch Plywood is not readily available and is quite expensive when I inquired about Special Order...and it must be ordered by the Flat.

So thats my comparison...at least based on Cost. Hope this sheds some light...and let the argument...begin again. LOL

BTW...The Cubs won, I got nearly half the list done and plenty of time to enjoy some music.

KAK

I'm not sure where your pricing your MDF, but I did the same thing within the last year (I built a DIY Sub). First I went to Lowe's. Their MDF reminded me of plain old particle board and was priced about what you quoted. I didn't really think about it at that time. The only reason I didn't buy was because I was prefering 1" material. I then went to my local Lumber yard that's been around as long as I can remember. I ordered a sheet of 1" without asking price. When it arrived, I about had kittens at the $49.00 price tag. Oh well, I ordered it. I guess, I own it. Once I saw the quality between the two, I understood why the 1" was so much more expensive. Lowe's is mis representing their product IMHO. Remember, "Buyer be Ware".

[kkerley33]

I went to Menards. Part of my Honey Do list was repairing a cabinet as well so I was only looking at Cabinet grade materials. They did have particle board there as well...it was dirt cheap (I want to say $7 or $8 a sheet) A lot of contractors use it for subflooring...especially in Attics. I have used it my garage as a backing for slot board I put up to hang yard tools from.

I was able to use the scrap of 3/4 Birch that I bought to make the repair and my roller cart for the speakers...with enough left over for the top of the center cabinet I want to make.

It is easy to tell the diference between MDF and Particle board. The first is weight. MDF is heavy as sin and you can usually get it already veneered.

KAK

[oldtimer]

Urban legend? Paul Klipsch was still alive when mdf was used instead of ply....Oh yeah, Hope is not considered urban.

[bigyank]

I built a pair of speakers earlier in the year and used double refined MDF. 1" thck 4x8 sheet was over 90 lbs. As in the earlier post, the stuff Lowes and HomeDepot sells is crap, plain and simple. Look on edge and the stuff at Lowes has different coloration. The double refined feels and cuts like concrete so if you are going to work with it, make sure you have an extra set of hands and some very sharp tools.

Here was my supplier within the mid-atlantic. They even carry up to 2" thick Double Refined MDF:

http://russellplywood.com/mediumdensityfiberboard.html

Yank

[JerolW]

' have used almost a pint of black paint and it is just soaking through.'

Try some sanding sealer. It should help.

jerol

[Guest " "]

"Paul Klipsch was still alive when mdf was used instead of ply."

which means?

[bigyank]

Missed that one. A paint I used which works perfectly with MDF and after 2 coats becomes waterproof:

http://www.acrytech.com/store.asp?pid=14119

Only issues I had were that while water cleanup did in fact work, you still had to work hard to cleanup. Results, awesome. I used a heavy splatter roller which made a stucco like finish but rounded tips. Also, self priming too[]

Yank

[oldtimer]

"Paul Klipsch was still alive when mdf was used instead of ply."

which means?

Which means that he authorized the use of mdf and if you want to go farther his favorite forte speakers which he had in his office were made with mdf, he loved them, so should you, ya? and get off your high horse about mdf enough said ja?

[Guest " "]

Paint on MDF chips easy.

[Guest " "]

"get off your high horse about mdf enough said ja?"

Don't have a horse

[oldtimer]

Sorry, thought you had a sense of humor, my bad. Mas didn't get the reference either, or at least chose to ignore it.

[Guest " "]

Here's some MDF vs comments from a cabinet maker website.....overall...it seems like some folks like the stuff....oh yeah...and some folks don't like it....

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

MDF is better in every category except one, cost. But the spread in cost is not as great as it once was.

I agree - MDF is always my preference even over veneer core, and definitely over particleboard.

If it's as damp in the summer as my garage, both materials are sponges and would swell like crazy. How about dropping a few extra bucks and using MDO?

From the original questioner:
I have actually left a piece or two of MDF outside for several weeks. I live in South Florida, and it was in the middle of summer. So needless to say, it rained a lot! The MDF really didn't look that bad. I would put it far above particleboard when it comes to moisture. I want to know about strength and ability to hold screws or nails. As far as MDO goes, it's just too expensive.

From contributor U:
MDF does not hold screws at all. It weighs a ton, unless you like the lightweight stuff. And underlayment grade PB is not much better. I much prefer a dense industrial grade PB core with melamine two sides, edgebanded on all edges - pretty much waterproof, and you can use screws. MDF is great as a consistent substrate for wood veneers or for paint grade work, but I do not get why one would build cases with it.

Melamine clad industrial grade particleboard is better all around. MDF for doors is okay, not boxes.

Please appreciate that particleboard comes in many styles... low density, medium, and high. It comes with a variety of glues and surfaces. It comes with different particle sizes.

MDF has less variability in market specifications. MDF edges can be exposed and finished without edge banding. MDF can be routed and even embossed. Particleboard will make a flatter shelf with less creep, especially if it has a solid wood face or edge.

Do not discount one product just because the standard fasteners do not work well. Use fasteners (and finishing) intended for that product.

Gene Wengert

I've spent the last 15 years convincing clients (mostly the time wasting know-it-alls) that MDF is an entirely different product than particleboard. It drives me nuts when people see a bundle of 5/8" super-refined MDF on the shop floor and visions of 3/8" particleboard Wal-Mart furniture go through their minds. There's a local shop that uses 1/2" CDx plywood with butt joints for boxes and drawers sides and claims "all wood cabinets" while knocking my deal! Give me a break, that's roof decking! What's next, 7/16" OSB? Amen to using the correct joinery and fasteners, be it with particleboard, MDF, thermofused melamine or veneer core plywood. By the way, if you're getting water, you don't need a different cabinet builder, you need a different plumber!

I use only confirmat on particleboard or MDF. It holds fine - never had a problem.

From contributor B:
They stopped making Pintos and Gremlins for a reason. The same reason they should stop making particleboard. Edge banded or not, it's still particleboard. What harm would it do to use good materials?

I use confirmats and Zip R screws in plywood and MDF. With a good hard kick the plywood joint will give. With a harder kick the MDF will too. But who's gonna kick a wall cabinet in a garage? Either one will work.

Don't take offense of my dislike for particleboard (unless you invented it). We all have our preferences and reasons for using certain products.

From contributor D:
What are you saying? I don't believe you are using plywood to make cabinets. I don't care how you wrap it, face frames or banding. When your done, it's still filler core sheets of "who knows what" held together with glue of some sort, with a tiny skin of pretty wood on (probably) only one side. Doesn't anyone make a solid wood (or solid lumber core veneer) cabinet anymore?

What is particleboard, wood chips and glue? What the heck is MDF, wood mush and glue? What IS this industry coming to..?

The "industry" is coming to safeguarding the meager profits allowed by the budget minded builder/consumer, through the use of cost effective materials. I honestly feel that MDF is a superior product to particleboard or veneer core plywood - machinability, appearance, joint strength, fastener holding, core density. I fought the downsides of plywood for years - core voids, inconsistent thickness. Have you ever noticed when someone comes in to get an estimate the first thing they say is "no particleboard!" but when you go by the project to see who/what bumped you out of the job, all you see is particleboard? The housing developments must consume a billion feet a month of this stuff.

Anyone using particleboard, please explain the benefits other than the $6.00 a sheet difference vs. MDF. Any known pitfalls? If it's working in your operation, more power to you. I'm considering getting on the bandwagon.

From contributor D:
You know I'm just razzin' you, buddy. I use the best products I can find for my operations. Good quality 3/4 VC plys have been getting harder and harder for me to source. It's not so much the cost as it is the inconsistency of product, lot to lot, even at the cost I must pay. Face veneers are getting more costly as the appearance quality continues to decline. With frameless cabinetry, as I am now doing, the thickness variance can wreak havoc with my desired 3mm reveals.

I like everything about MDF core ply except two things. For my assembly method, I find that MDF tends to split more easily when edge fastening and that tendency also concerns me that the fastener holding ability is compromised. The second objection is that (though I do my best to capture machine dust) the dust from MDF is powder fine and my respiratory system lets me know at the end of the day that I have been breathing MDF dust, even in relatively small amounts. PB seems to come off the blade in chips, with much less dust in the shop air. The first objection could be overcome were I to use conformat screws or dowel construction, but since I don't I believe that high grade (don't laugh) PB holds my Zip-R screws better.

There is another issue that keeps me from using MDF core products. I dont have a local source for MDF core melamine and I do prefer white mel as my standard interior. The 6.00 (or 36.00) difference in cost is not of much concern to me Im not running a factory and I (and my target market) would not have a problem with a couple hundred dollars added to the materials cost of most any of my jobs. One last comment: If you could go back a year or two into the archives of this forum (and a few other woodworking forums), you would find that I was one of the most outspoken advocates of VC ply carcasses and a diehard bigot of anything containing PB or MDF.

From contributor U:
There is a huge difference between industrial grade (very good), commercial grade (okay), and underlayment grade (Wal-Mart) particleboard. One must first know the difference to make an educated decision about this subject.

Regarding MDF, no screw will hold reliably in the stuff, period. MDF is much more likely to split if you do try to use screws. Cabinets built from MDF weigh a ton! On the plus side, MDF is unrivaled as a substrate for wood veneer and for paint grade millwork.

MDF for cases? No thank you very much. I'll take melamine with an industrial grade PB core anytime.

From contributor J:
The melamine cases have me intrigued. To those using melamine, are you using thermofused or cold rolled? As I don't do any finishing, what problems will be encountered with on-site finishing (melamine interior with wood RP doors/fronts)? Do you use wood edgebanding on melamine cases? Do you band all exposed edges or only those visible (front edge)? What about finished ends and wall cabinet bottoms? I think the melamine interior would be great.

Particleboard comes in many different qualities. To say that MDF outperforms or whatever particleboard is like saying a Cadillac outperforms a Ford. You need to specify what job you are considering... a F-350 Ford pickup will outperform a Cadillac when hauling, on back roads, etc., while the Cadillac might win on a smooth road considering ride comfort and quietness.

Too many people think that particleboard is hunks of wood haphazardly glued together. Not true. Particleboard is an engineered product with specific properties that must be met to have it graded in a specific grade and usage grouping. Particleboard today is not like the stuff we used for cabinets and so on in the 1950s. In many uses, especially structural, and in fastening, particleboard will greatly outperform MDF.

Incidentally, what is MDF? It is the same wood used for particleboard, except it is made smaller (fibers or groups of fibers) before it is glued back together. It uses the same adhesive, too! The June 2002 issue of FDM magazine had a nice summary of the composite board definitions. Read it before making statements that are not really true but that need qualifications.

Regarding plywood: Again there are grades of plywood which reflect the intended usage. Some folks, however, do not adhere to the grades and therefore will not sell graded plywood, but just plywood. It might look the same on the outside and sell for less, but it is not equal to the good plywood product whose quality is determined by the HPVA.

Gene Wengert

From contributor J:
I'll stand corrected on my knowledge of particleboard. I agree today's particleboard is not the stuff from the 50's. However, most consumers fail or refuse to recognize that fact, and assume that someone using particleboard is offering and using cheap materials and construction. Not so. The manufacturers of particleboard don't seem to make an effort to educate the end user (homeowner) on the different grades and benefits of their product. As I said earlier, the melamine cladding would be a super finish inside - hard to compare with any sprayed finish.

From contributor B:
True, PBC materials are better than they've ever been. But it's still particleboard. Put that in a cabinet here and you won't last. Like one guy said, folks see it and their thoughts turn to wallyworld KD stuff.

Contributor D, MDF dust is a monster! And you hit it right on with today's veneer cores not being consistent.

A well-built cabinet will last, whether it's plywood, MDF, or PBC melamine. I prefer plywood because of weight and dust. MDF dust kills my nostrils, melamine dust irritates my eyes.

I use a lot of PBC rock maple melamine. My supplier keeps it just for me. Makes a pretty interior. Some folks prefer it. Some even like the white. Those folks believe me when I explain the quality. But most think I'm trying to sell cheap stuff to increase my bottom line. I tell them the only difference in price is in the finishing - melamine is cheaper. Plywood costs about $6 a sheet more, but my aching back is worth that. I've built with a lot of MDF, too. If pre-drilled and done right, it won't break or split as easily as PBC or some veneer ply. Some of the ply I'm getting lately is terrible, though.

My #1 choice is lumber core Agathis plywood because it's lightweight, paints and stains well, and is fairly consistent in color. But now it's up to $31.50 a sheet, a tad more than veneer shop birch. I just like it. But most importantly, my high-end customers do too.

From contributor U:
Contributor J, to answer your questions about melamine -

I edgeband the fronts to match the exterior finish, using PVC banding. To do that, you need to know the exterior finish color in advance. I use "glue back" melamine for my finished ends, and apply wood veneer with waterbase contact cement after assembly. My wall cabinet bottoms are two-sided melamine (mostly white), raised 32mm up, with a 32mm light skirt below. Great for undercabinet lights, and no veneer or finishing required.

I band my adjustable shelves 4 sides. Parts for the sink cabinet and any cabinets exposed to water get banded 4 sides. Otherwise just the exposed edges get banding.

For finishing, I only need to remove the doors and drawers, and mask off the finished ends.

MDF is a better substrate than industrial or commercial grade particleboard substrates.
It is also more expensive and heavier.

If you want to upgrade a bit because of moisture worries there is one type of MDF that is quite moisture resistant. I left some outside for two weeks and it was rained on several times. It was laminated with a phenolic resin paper. The only exposed board was the edges and they did not swell. It was used later for concrete forms.

The board's brand name is MEDEX. It is a Sierra Pine product. It can also be had with TF melamine on it (Hard Rock Maple even). This product is heavier, more costly, and harder on cutters. It may not be easily available as the mill that makes it is in western Oregon.

I would agree with most of everything already said about PB vs MDF. Take a piece of MDF and soak it for 24 hours and do the same with PB. Let it dry for 48 hours. This will make up your mind in a hurry. Medex is an excellent product that we use all the time for sink countertop substrates.

The comments below were added after this Forum discussion was archived as a Knowledge Base article (add your comment).

Comment from contributor A:
We have found that MDF suits our needs in the commercial store fixture industry. It has a consistent thickness throughout the sheet, comes in a wide variety of sizes (thickness, width and length), and depending on the type you buy, it machines extremely well. Add to these positives the fact that it paints exceptionally and you have a universal board. Also know that you can buy a MDF product known as Medite or Medex. This has some moisture resistant properties - something you may want to check with your supplier on.

Comment from contributor C:
Each product has its place. Particleboard is very smooth, consistent, and holds screws and other fasteners well. MDF has a smoother finish, takes machining very well, but doesn't hold screws too well. Use dowels or other fasteners. MDF is heavier than particleboard. Lightweight MDF is great, but can't be trusted to hold a screw at all. Veneer-core plywood is fine, but the thickness (or should I say thinness) of veneers means it is very hard to sand without sand-throughs because of the uneven surface. We use all of these products, plus melamine panels, in our custom office furniture, because each has its own good features and bad. Solid wood panels are too hard to make and too expensive to consider.

We do a lot of veneer tables with solid edges, using particleboard and MDF, and we can sand them on a widebelt. Can't do that with veneer core plywood without sandthroughs, even on expensive sanders. HPL always gets a particleboard core.

Comment from contributor E:
I work for a custom/semi-custom fish tank manufacturer. We use MDF on some of our cabinets that will be holding 200+ gallon tanks. We use nothing but wood glue and brad nails on all of our joints. The brads are basically used to hold the joint together while the glue dries. We've never had a failure that I'm aware of even with the thousands of pounds that sometimes rest on our cabinets.

If you can get away with it I would stick with glue joinery on MDF and stay away from mechanical fastening as much as possible.

Comment from contributor M:
For cabinets, I prefer plywood in the box and natural wood for faceplates. I like the ease of MDF for the center of painted doors (will not split and machines well) or machining trim works for painted surfaces. I would not build my boxes out of MDF, nor would I use it for shelving. MDF works well for both square and round post because of its easy painting, machining and I think superior glue hold with brad nails. As far as facing plywood edges, I prefer a 1' facing instead of a veneer. Biscuits work well and it cross grains for support.

Comment from contributor S:
Why restrict you carcass material choices to PB or MDF? As noted already by others, mechanical (screws, etc.) joinery in these products is usually sub-par. Having been a woodworker since my teens and now a general contractor, with a number of years spent working in a small lumber yard that catered to cabinet shops and custom wood workers; my vote for carcass material is lumber core (LC) material.

We sold more LC Luan sheet material for carcasses than any other sheet good we stocked. This was in Hawaii, where humidity isn't of Floridas proportions, but substantial, still. The LC sheet product is the choice of most local shops for carcasses as it is more stable than veneer core (VC) and doesn't weigh as much as MDF. MDF tilts the scales at 99 lbs a sheet. If memory serves my correctly, the LC was about half the weight of MDF.

Granted, the MDF lends itself to a painted finish better than most other products. Case in point, one day a regular customer brought in a painted raised panel door for us to see. It turned out that it was one a one piece door made from MDF and CNC routed to look like a raised panel. Flat as could be, stable, no panel rattle due to changing conditions, and the weight gave it a feel of quality. A Euro hinge with a cup in the door allows the screws to hold the MDF without worry of fatigue, as opposed to a non-cup style hinge.

Comment from contributor P:
I've never made a cabinet, but I can say I use MDF to make subwoofer and speaker boxes on a regular basis and I've only had a couple of cases where the MDF has cracked and that was mostly because I was in a rush and jamming wood screws into the box with a drill instead of taking my time. On the other hand everything I've owned that was made of particleboard has in some way or another been damaged beyond repair.

[Jay481985]

I built a pair of speakers earlier in the year and used double refined MDF. 1" thck 4x8 sheet was over 90 lbs. As in the earlier post, the stuff Lowes and HomeDepot sells is crap, plain and simple. Look on edge and the stuff at Lowes has different coloration. The double refined feels and cuts like concrete so if you are going to work with it, make sure you have an extra set of hands and some very sharp tools.

Here was my supplier within the mid-atlantic. They even carry up to 2" thick Double Refined MDF:

http://russellplywood.com/mediumdensityfiberboard.html

Yank

depends on the home depot and lowes. Being that I live in New Jersey I can basically go down 5 more miles to see a better store. I went to around 5 different home depots and lowes each and noticed that some buy cheaper grade wood and that goes for everything in the store. Some stores did not carry the minwax ebony and when I asked they had no clue what I was talking about while another store was like which size, pint or quart?

Some of the better stores I remember carried georgia pacific mdf which was pretty good while some other home depots carried things that reminded me of crushed cardboard.

[colterphoto1]

your point is?

Try having void free plywood manufactured 1" thick. The 3/4" was 7 ply, so we'd need, what like 11 ply perfect void free plywood? Do you know how little of that is made in the world?

Another little complication, to avoid waste, the old LS were nearly perfect cuts from 4x8 sheets. If you make the cabinet just the teensiest bit larger (like to get the 1" thickness the walls are slightly larger exterior dimensions) you need to go to larger sheets or have a tremendous amount of waste. Klipsch uses 5x10' sheets of the MDF. Now we want it milled so that it can accept dado joints for more strength, ever try that with plywood?

NEXT!

[colterphoto1]

Fritz,

I can attest to the paint thing. I also built a set of Roller Platforms to put the LS1's on. I bought a sheet of the pricey Cab Grade Birch Plywood, they had a damaged piece so it only cost me $20.00. I have used almost a pint of black paint and it is just soaking through. I haven't hit the Lacquer yet. I may just not use Lacquer since they are only going to be "wheels" anyways to save the floors.

When I get around to building the Center, I will let you know.

My thought is to take the readily available plans for LS boxes from the internet and cut the Hieght in half since I will not be using the low end anyways. That should leave enough room for my DVD player, dish box and integrated Amp to fit in the opening. I will leave the back open to improve airflow.

Question to you is, where do I aquire the Horn, Midrange Drive, Tweeter and crossover? Should I attach anything for the low-end such as a passive sub off to the side? I have 2 twelve inch passive sub boxes sitting in the attic.

Any thoughts?

KAK

Try priming the wood first.