[rklein]

Hi:

I recently purchased some SS drivers from Rick and also from one of his customers out in California.  I am planning on making the "Texas Tower" that Fred down in Texas made.  I was talking with a woodworker/cabinet guy who has done work for me at my home in the past about my project and I asked about possible sources for good MDF (not all MDF is the same...).  I also mentioned possible sources for veneer.  His response was why do that when you can order MDF Core Veneer?  He turned me on to a product that looks very good!  See the below link...

http://www.cfpwood.com/products/default.aspx

You can either get regular plywood veneer or MDF core veneer.  If you scroll down on the right side you will see the available veneers(you can also special order a species not listed).  The price for a 4x8 sheet of 1" MDF Core with a Walnut veneer is $98. 

Has anyone gone this route for DYI'ing speakers?  One of the questions I have is that on the above website it mentions that the MDF Core is "Medium Density".  However, it is also very low in it's Formaldyhyde content.

Pro's or Cons over the MDF and then applying veneer method??

Thanks,

rklein

[tcsubwoofer]

Sounds like a good project.  Let us know how it goes.

I used some MDF core veneer this last summer to build a large built in bookshelf.  I used it for the shelves since it bows less over time than veneered plywood.  Nice material.

Being on the final stages of an RC-5G kit the one thing I've learned is that the cuts for a speaker using preveneered MDF would have to be extremely accurate which is hard to do with a hobby setup.  I'm pretty anal being an engineer and I'm pretty satisfied with my work so far, but I was still off by as much as 1/16" on a couple edges which is really a fairly large gap on a speaker.  Since I was using veneer over the box this was easy to fill and sand with wood putty before pressing the veneer.

If you use preveneered MDF all of your joints would have to be mitered I believe otherwise you will be showing end grain of the MDF.  If your box is rectangular or square this is a lot easier versus a box without perpendicular angles.  While you may save time and money in not having to press veneer you will spend a lot of time trying to cover up and correct any edge mistakes you may have made which might be hard to match and pull off.  As my first effort in doing veneer I was worried that my edges would be bad, but in fact they came out nearly flawless and look like a solid piece of wood.  Not so sure you will get that with mitered MDF core.  Just my 2 cents and I'm open to hearing what others think.

I would use double refined MDF which is very strong for MDF.  I bought some at a good local wood company in the Denver area (should be easy for you to get in your area).   I'd also stick with cold press veneer or perhaps iron on since the wood you are choosing is easy to acquire. 

[rklein]

Thanks for your reply tcsubwoofer.  I was thinking of copying the below design(although I am using two Scan-Speak 7" Revelator woofers and a Scan-Speak AirCirc tweeter in a "MMT" format)

http://www.taylorspeakers.com/html/bifrost.html

I was going to apply a piano high gloss finish to the sides.  It would seen the only places I would have to worry would be the seam between the top and front/back of the cabinet.  I am still undecided as you have stated to use a "double refined MDF" and the MDF core is listed as "Medium Density". 

Thanks,

rklein

[rklein]

Below is the original thread on the speakers I will be building.

http://www.audiocircle.com/index.php?topic=58819.0

Thanks,

rklein

[mcgsxr]

I would think that all MDF is medium density, as it stands for Medium Density Fibreboard... http://en.wikipedia.org/wiki/Medium-density_fiberboard

Are you looking for HDF?  http://en.wikipedia.org/wiki/Hardboard

[rklein]

I would think that all MDF is medium density, as it stands for Medium Density Fibreboard... http://en.wikipedia.org/wiki/Medium-density_fiberboard

Are you looking for HDF?  http://en.wikipedia.org/wiki/Hardboard

I am not looking for HDF.  Your reply makes perfect sense to me... I didn't put two and two together...

I would use double refined MDF which is very strong for MDF.

This reply through me off a little. 

Thanks

rklein

[planet10]

I am still undecided as you have stated to use a "double refined MDF" and the MDF core is listed as "Medium Density". 

You could just bypass that dilema and use plywood... (the more plys the better -- the 18mm baltic birch we use has 13 plys) I've also seen ply with MDF as the outer layers to make finishing easier (haven't tried that)

dave

[planet10]

I would think that all MDF is medium density, as it stands for Medium Density Fibreboard...

MDF comes in all sorts of grades, from stuff that you can almost crumble in your hands up to stuff that should really be called HDF.

dave

[Christof]

If you have the ability to make clean & accurate cuts it sounds like the way to go.  I typically press up one 4x8 sheet and then break it down into panels rather than press individual panels.  I not would expect much it the way of "figured" wood for this price but for your boxes this 1" veneer core should work very well.  Just a thought, maybe you can have your friend press up something special for the baffles and use the 1" walnut for boxes.

 

[mcgsxr]

I am with Planet10 on this one, having built speakers with both mdf and baltic birch ply, the ply is well worth the extra expense, and effort.  My current OB speakers are still in raw mdf form, but my intention all the long (alright it has been almost 4 years...) has been to make the final baffles with baltic.

[tcsubwoofer]

I am with Planet10 on this one, having built speakers with both mdf and baltic birch ply, the ply is well worth the extra expense, and effort.  My current OB speakers are still in raw mdf form, but my intention all the long (alright it has been almost 4 years...) has been to make the final baffles with baltic.

Have you found that due to plywood expansion and contraction differences between the face and edge of plywood that the edge/ends might show through veneer with time for those joints that might have the edge/end exposed (i.e. a butt joint versus a mitered joint)?  I also recollect that MDF was better at dampening sound than plywood though I could be wrong.  Thoughts? 

Since a speaker usually only requires about 2 or 3 panels of material I think buying good MDF or plywood is a wash.  I paid $36 for 3/4 double refined MDF and $51 for 1" thick MDF.  I do think it is about twice that for birch or red oak ply - nothing that breaks the bank.

Given that the Texas Tower is being modeled after Taylor speakers and the front, top, and back use veneer while the sides appear to be capped with MDF or solid wood in a black piano like finish it does seem like using preveneered wood would be more of an option for the center veneer.  You would only have 2 visible seems to deal with.

[Rick Craig]

Hi:

I recently purchased some SS drivers from Rick and also from one of his customers out in California.  I am planning on making the "Texas Tower" that Fred down in Texas made.  I was talking with a woodworker/cabinet guy who has done work for me at my home in the past about my project and I asked about possible sources for good MDF (not all MDF is the same...).  I also mentioned possible sources for veneer.  His response was why do that when you can order MDF Core Veneer?  He turned me on to a product that looks very good!  See the below link...

http://www.cfpwood.com/products/default.aspx

You can either get regular plywood veneer or MDF core veneer.  If you scroll down on the right side you will see the available veneers(you can also special order a species not listed).  The price for a 4x8 sheet of 1" MDF Core with a Walnut veneer is $98. 

Has anyone gone this route for DYI'ing speakers?  One of the questions I have is that on the above website it mentions that the MDF Core is "Medium Density".  However, it is also very low in it's Formaldyhyde content.

Pro's or Cons over the MDF and then applying veneer method??

Thanks,

rklein

The quality of the core is usually good with the pre-veneered MDF sheets; however, the veneer can really vary and you cannot make matched cabinets.

[rklein]

Thanks for all of the replies.  I appreciate it.  

The quality of the core is usually good with the pre-veneered MDF sheets; however, the veneer can really vary and you cannot make matched cabinets.

I agree with Rick.  However, a local company(Cleveland Plywood) stocks the MDF Core with most of the standard veneers, so I do have the ability to go and select a couple of sheets to try and match them as closely as possible.

Thanks,

rklein

[jons]

Thanks for all of the replies.  I appreciate it.  

The quality of the core is usually good with the pre-veneered MDF sheets; however, the veneer can really vary and you cannot make matched cabinets.

I agree with Rick.  However, a local company(Cleveland Plywood) stocks the MDF Core with most of the standard veneers, so I do have the ability to go and select a couple of sheets to try and match them as closely as possible.

Thanks,

rklein

Also, remember that matching only really matters when you get into the more exotic woods with different figures in it.  Just plain walnut really isn't going to matter. 

Those are some pretty awesome speakers, I would really like to build a set.  It would be fun to do a comparison with my Seas Thor kit. 

[James Romeyn]

Aug '08 Stereophile Industry Update had a brief history of speaker panel materials since the '40s.  The article included a new, affordable, reportedly better-sounding laminate recently developed & employed by two British designers:

2/3 MDF particle board or MDF (article states the jury is still out which of these two materials sounds better when employed alone)
1/3 classic BB ply

I wonder why they didn't just split the materials 50/50?  Maybe a simple byproduct of the availability of certain panel thicknesses?       

A unique bipolar speaker is planned w/ separate .5cf enclosures up/down; considering 1.25" laminate, 3/4" PB + 1/2" BB ply. 

My favorite standmount is built from solid 32mm (1.25") ovangkol (AKA schedua).  The best known price for ovangkol is $18/board foot (ouch!).  A .5cf enclosure (not including front/back) would require about $90 worth of ovangkol; a little steep to say the least.

I cloned the above standmount & will shortly compare the sound of the ovangkol vs. the above-described PB/BB ply laminate.       

[cadobhuk]

What was the best stand mount you've heard? How did other standmounts you've heard compare?

[James Romeyn]

I edited the post to "my favorite standmount"; it's not one of Rick's wonderful speakers so only PM is appropriate. 

The Selah RC3R is among my favorites & definitely preferred over the following speakers priced between $4k-$7k/pr USD MSRP as of mid-late '08:

KEF 201/2
Dali Helikon
Dynaudio Confidence C-1
Esoteric (Teac, made by Tannoy of England) MG-10

[EARGASM]

Removed by member.