Hello everyone, (sorry about the essay!)
I will cut right to the chase, I have only ever built one speaker two 3" full range shielded drivers in a sealed cabinet small enough to fit on my desktop amp when i was in high school. I originally built it out of pine mainly because it was the only thing my school shop had access to, I have since out-grown it and I am looking to build a new pair.
From all of the research I have done it seams the universal opinion is that Baltic Birch plywood is the material of choice when it comes to building speaker cabinets.
I have recently found a local timber re-seller that stocks Baltic Birch plywood. I submited a request for a estimate of one sheet measuring 2400mm x 1200mm x 19mm.
I plan on building a two way cabinet using the B&C 6NDL38 6.5" Woofer and the B&C DE35 tweeter.
The timber re-seller has two different types of ply with a significant difference price.
Also of note is that I am going to have the cabinets cut out on a cnc router because it is cheaper than the upfront cost of tools/equipment to do it myself and I want to recess the woofer and it is a awkward shape.
Option 1:
B/BB FSC Birch Plywood for $215
Pics:
Face: Brirch Ply FSC Face.jpg - Google Drive
Edge:Birch Ply FSC Edge.jpg - Google Drive
Option 2:
B/B Birch Plywood with Acacia core for $125
Face:Birch Acacia Ply Face.jpg - Google Drive
Edge:https://drive.google.com/open?id=1AMe-Pk_Tn_naQR5Ab63scja8RbE8MAHU
I am leaning towards the Birch with the Acacia core because the face looks to be of far better quality, and the price.
Now the actual question.
Does the Birch with a Acacia core preform any worse than the regular Birch, and if so is it very noticeable?
Thanks in advance for the help.
I will cut right to the chase, I have only ever built one speaker two 3" full range shielded drivers in a sealed cabinet small enough to fit on my desktop amp when i was in high school. I originally built it out of pine mainly because it was the only thing my school shop had access to, I have since out-grown it and I am looking to build a new pair.
From all of the research I have done it seams the universal opinion is that Baltic Birch plywood is the material of choice when it comes to building speaker cabinets.
I have recently found a local timber re-seller that stocks Baltic Birch plywood. I submited a request for a estimate of one sheet measuring 2400mm x 1200mm x 19mm.
I plan on building a two way cabinet using the B&C 6NDL38 6.5" Woofer and the B&C DE35 tweeter.
The timber re-seller has two different types of ply with a significant difference price.
Also of note is that I am going to have the cabinets cut out on a cnc router because it is cheaper than the upfront cost of tools/equipment to do it myself and I want to recess the woofer and it is a awkward shape.
Option 1:
B/BB FSC Birch Plywood for $215
Pics:
Face: Brirch Ply FSC Face.jpg - Google Drive
Edge:Birch Ply FSC Edge.jpg - Google Drive
Option 2:
B/B Birch Plywood with Acacia core for $125
Face:Birch Acacia Ply Face.jpg - Google Drive
Edge:https://drive.google.com/open?id=1AMe-Pk_Tn_naQR5Ab63scja8RbE8MAHU
I am leaning towards the Birch with the Acacia core because the face looks to be of far better quality, and the price.
Now the actual question.
Does the Birch with a Acacia core preform any worse than the regular Birch, and if so is it very noticeable?
Thanks in advance for the help.
Sorry it has taken so long to reply.
-Does the stiffer acacia laminate have an effect on sound?
-The birch plywood with the acacia core is about 1.4x stiffer compared to the regular birch sheet. Seller said it is commonly used as a indoor floor substrate. The other birch is used to make luxury kitchen cabinets.
-The birch with acacia core is 6 thick plys of acacia with a thin birch face. The other is 9 thinner plys of birch only.
-Does the stiffer acacia laminate have an effect on sound?
-The birch plywood with the acacia core is about 1.4x stiffer compared to the regular birch sheet. Seller said it is commonly used as a indoor floor substrate. The other birch is used to make luxury kitchen cabinets.
-The birch with acacia core is 6 thick plys of acacia with a thin birch face. The other is 9 thinner plys of birch only.
Plywood is a sonorous material. Parasitic resonances will appear
For acoustic boxes probably need to take a material with low Q, such as MDF. Or marble (not joke)
For acoustic boxes probably need to take a material with low Q, such as MDF. Or marble (not joke)
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Would help to have the edges side-by-side in the thread rather than some Drive.
To my eye, I'd pay $5 more for the more-ply product; but NOT $100 more. I rather doubt any but the most experienced golden-ears would know the difference in residential speakers. (Road-PA speakers do need tough wood because roadie-abuse opens up the plywood and it can buzz.)
The mimosa-core has a visible void-- this is a cheaper construction with a cheap wood. I had no idea mimosa could be structural, though I use Luan and that's also cheap wood.
To my eye, I'd pay $5 more for the more-ply product; but NOT $100 more. I rather doubt any but the most experienced golden-ears would know the difference in residential speakers. (Road-PA speakers do need tough wood because roadie-abuse opens up the plywood and it can buzz.)
The mimosa-core has a visible void-- this is a cheaper construction with a cheap wood. I had no idea mimosa could be structural, though I use Luan and that's also cheap wood.
Attachments
That is a pretty low ply count. The 18mm stuff we use has 15 plies. Use whichever material is stiffer… that pushes any potential resonances up high enuff that they will not likely be excited. And any piotential resonances will be hi-Q which means they need a steady sustained input in a very narrow bandwidth, something that rarely happens with misic.
dave
dave
'Some' say MDF is to be avoided at all costs, except the larger 'some' use it in most speakers made on the 'planet', all the while giving reasons, akin to the use of unicorn poo as an aphrodisiac, why their choice is so much better.
I have used MDF several times and cannot hear a deficiency. Why not use it and use the balance of the budget for some very nice veneer?
BTW, how much will those drivers cost to get to OZ? There are many drivers, just as good if not better, to be had here at a reasonable cost.
I have used MDF several times and cannot hear a deficiency. Why not use it and use the balance of the budget for some very nice veneer?
BTW, how much will those drivers cost to get to OZ? There are many drivers, just as good if not better, to be had here at a reasonable cost.
Tromperie,
Yeah I just got past the research phase to the budgeting. With current currency conversion
it would run about $940. That includes
- 2x 6NDL38 Woofers
- 2x DE35 Tweeters
- 2x Dayton Audio 4.5K 2-way crossovers
- 1x WF60PA full range amp with wifi (I plan on streaming from s media server)
- Terminals, Mounting hardware, and Batting
Still a bit rich for my blood do you have any suggestions on alternatives?
Yeah I just got past the research phase to the budgeting. With current currency conversion
it would run about $940. That includes
- 2x 6NDL38 Woofers
- 2x DE35 Tweeters
- 2x Dayton Audio 4.5K 2-way crossovers
- 1x WF60PA full range amp with wifi (I plan on streaming from s media server)
- Terminals, Mounting hardware, and Batting
Still a bit rich for my blood do you have any suggestions on alternatives?
Thank You!
Thanks everyone for the input looks like i will be going with the cheaper brich plywood with acacia core.
Thanks everyone for the input looks like i will be going with the cheaper brich plywood with acacia core.
You should include also two variable L-Pads ( 10-15 $ each ) to make the tweeter level match with the midwoofer ( without any filter the level @ 1W/1m is well above 90 dB, though if you have to equalize it for bass it will droop below the 90 dB "line", but being the speaker for PA use it will never have enough bass, so better to keep it above the 90 dB line )
I'm sure it would sound good, but I think the Birch plywood with Acacia core is more of a birch veneer over acacia ply. This will be different to birch ply, which is very dense, I would hazard a guess the weight is at least 1/3rd less. And probably designed for lining vans or something that requires less density. I could be wrong.
Lots take the approach of a lighter material, just stick loads of bracing in.
You could probably get the birch cut in Europe on a beam saw (CNC but not router) for way less and sent over on a pallet, you can get good birch ply here in the UK for £40 and £15 to cut up.
Lots take the approach of a lighter material, just stick loads of bracing in.
You could probably get the birch cut in Europe on a beam saw (CNC but not router) for way less and sent over on a pallet, you can get good birch ply here in the UK for £40 and £15 to cut up.
Murphy ply from Portland. A 13 ply core and they add a maple ply on either size. Put a caliper to a piece and it is somewhat over the nominal 18mm thickness.
dave
Shows how well the marketing departments have done promoting MDF, its only advantage being that it is cheap (to buy, to work, to finish).
dave
McFluffels is a long way from the Baltic. Far end of the world.
He's got a choice including an Australian wood I'd never seen sold for lumber. Just as he'll never see Maine Pine except as an exotic. He'll never see a Moose and I'll never see a Kangaroo in my yard. Different down under.
I think he's been told right. The all-Birch is fancy kitchen cabinet. Stable, and does not show voids on cut edges. The mimosa-core is more economical, probably still stable and strong, at least for flat-work without exposed edges (floor underlay). Underlay panels *may* warp if unconstrained (nailed to joists), cabinet doors shouldn't. However a speaker box constrains all its panels.
All respect to Dave who has tuned many more speakers than me: I'm not sure "stiff" is a primary goal. Double stiffness (if possible) moves panel resonance 1.4X higher, not much; and may move it to a more audible range. Above resonance, sound transmission is all about the Mass, not the stiffness. It would be good to have Damping, but that is harder than it looks. We like wood because it has more damping than many materials; still we use wood for Marimba bars, so wood can be ringy.
For all your bleating about MDF, there is no evidence to support your claims. Would you please ease off until there is some?
For normal hifi, I don't think you need such high power capable drivers when you will never drive them to that level. I use SB Acoustics woofers and mids, as my signature shows, and they aren't ever pushed to full volume with the LM3886 60W amps that drive each. There are other drivers, such as SEAS and Visaton if you like a little pricier, that will do the job.
I see you are buying a premade crossover. Is that made specifically for those drivers?
Have you factored in freight from the US? It is very expensive.
I think Dave should make a dedicated, why MDF sucks thread and just repost a link to there. I have seen him defend ply and lament MDF lots of times.
G' Day Mate,
I hate to tell you this , but the list of components that you propose is not hi-fi
at that price point .
For what it looks like that you are proposing , 20mm mdf will be just fine .
But please go ahead and build what you propose , then work on this for the next few years .
regards
I hate to tell you this , but the list of components that you propose is not hi-fi
at that price point .
For what it looks like that you are proposing , 20mm mdf will be just fine .
But please go ahead and build what you propose , then work on this for the next few years .
regards
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