[JohnR]

Just curious Please post here if so.

Reason I ask, I found a place just down the road from me that sells cuts for wood turning, but also has some boards and planks that could be nice for speaker baffles. We have such a unique flora here, I'm wondering if anyone is taking advantage of it in their audio gear (or related furniture, racks etc).

Not exactly on topic, but here's a violin carved from native materials (I took the photographs) -

[WerTicus]

real wood isn't good for speaker boxes.

It will expand and contract and you will end up with an unsealed box or joins needing resin to fill them.

[JohnR]

So far all my boxes with real wood baffles (7 of them) are fine...

[JohnR]

Today I talked to the chap who made the violin pictured above. He explained a few things to me, which I found interesting. One is that to make a violin (or cello etc) he selects quartersawn wood, which is least prone to cracking. He also said that the way the violin is constructed ensures that the wood doesn't crack - the end grain is sealed, and the curve in the belly and back allow for some movement of the wood.

For guitars (he also makes classical guitars), the wood is glued to struts across the grain. However, it is glued up in a dry cabinet, so that the wood might (try and) expand but not contract later - contraction, I surmise, is what causes cracking.

Now I'm not an instrument maker but this was quite interesting. He also suggested looking up specific species online to get the measure by which that wood changes with humidity, there is a standard way of measuring it.

I suspect that the admonishment against using solid wood in speakers is more a matter of taking due care - it may be easier to get wrong than using MDF (or plywood), but that doesn't mean it can't or shouldn't be done. And, of course, you don't have to veneer it

[WerTicus]

very interesting, I'm guessing the wood cabinets I've seen were not made by a true pro.

[JohnR]

I was thinking there might be other projects as well that could use some of our unique woods. Front panels? Racks? Just thinking out loud here

Here's the place near me that I mentioned - this page shows some of the woods

http://bradsburls.com.au/sections.htm

[Mr Content]

John, I have been asked a few times to finish speakers with a wood panel over the MDF or HDF cabinet, It can look stunning in some of the darker timbers, but I tend to shy away from using just wood alone. In big panels, it definitely rings more that an MDF/HDF cab. Also I feel that a multi layers of dissimilar material works best for speaker cabs...............But I admit that I am firmly in the "make the cab/panel, as inert as you can" camp, with will show in my opinions

Mr C

[bluesky]

Hi John

My local woodworking club goes out every month or so to collect wood from local farmers and then it is air dried under big carports at the club house. 

So you get wood like Mango, Avocado and lots of wattle.  Beware of some of the wattle species though as the saw dust can be quite carcinogenic.  I have been meaning to find out more about Australian timbers and if we have something that is close or matches the specs of Maple that those in the States use for all manner of audio stands.

Ian

[andyr]

Just curious Please post here if so.

I've had frames made up for 2 sets of Maggies from Oz hardwoods (to replace the 18mm MDF frames they come with, stock):

* the 1st set was a single frame each side; these were made of ironbark.  Very dense and very difficult to work - I had wanted the splanks of wood to be joined by mortice & tenon joints but the ironbark was too hard for the furniture maker's m&t machine to work on, so he had to use dowels & disks to join the 4 planks.  So probably, in retrospect, this was not a good choice of wood.  But they did make my Maggies sound better. 

* the 2nd set had 2 frames each side (to separate the bass panel from the other 2 drivers) and was made from 'Forest Red'.  (Hadn't heard of this before but that's what the furniture maker called it.)  Still dense but easier to work than the ironbark - so he was able to use m&t joints.  The wood has a lovely red tinge and a slightly wavy grain, so looks great.

I also had a plinth made from Tasmanian Myrtle for my LP12.  This has a curly grain and is a work of art.


Regards,

Andy

[mandoman]

I have made plenty of speaker cabinets from solid Australian native woods, Jarrah, Myrtle and Tassie Oak.  No problems with air leaks or splitting.  Some are now over 10 years old and still no problems.  The secret is proper design.  You need to assume the wood is going to expand and contract across the grain and design the cabinet accordingly.  You can safely assume little or no movement along the grain, however.   I don't make the front baffles from wood, they are always MDF.  So top, back, sides and bottom are glued, back and front baffle are not glued but are screwed on with a rubber seal so they can move.  Careful how you glue bracing, don't glue long grain across the grain.  I make prototypes from MDF and the final cabinet from wood, and in every case the solid wood cabinets have sounded better than the MDF.  I think that is because the wood is much much stiffer and somewhat heavier than MDF.  The biggest difference I have found was between MDF and Jarrah.  Of course solid wood is going to move with changes in humidity, but don't let that stop you.  Try and get quarter sawn wood if you can.  There is a lot of BS said about the unsuitability of solid wood.  The only problems are actually availability and high cost.

I make music instruments, so am very familiar with how guitars, mandolins and violins are made.

[jules]

I've used Australian red cedar and Huon Pine as boxes for pre-amp, amp and a turntable and Tallowood for external, 75mm X 50mm circumferential bracing "belts" around an MDF sub. I figure the stiffness of the Tallowood will make up for something of a deficit in that department for MDF, without causing any ringing [if that's really a problem]

Do I have any measurements .... ha, ha, ha, no.

[coffeebush]

I am no woodworker but my recent build of a cascadetubes.com circuit 6as7 Purple Heart amp I used a local timber. It was Grevillia robusta I believe cut from rough and gnarly plank I found on Facebook. Just had enough to finish the job after making wrong measurements