That (sure looks like) Plyboo Neopolitan stranded bamboo plywood. We used a sheet of it to build a number of miniOnken. Comes in 4'x6' sheets and ends up running close to 4x the price of the quality ply we use. Very dense and heavy, shipping from the US could come close to the purchase price.
Construction, tooling, & cost issues aside, the nicest sheet material we have yet used for speaker builds.
dave
The DGAFs
Meet the DGAFs:
As the name might imply, these speakers were the result of a late night at MIT. I designed them in HornResp in about an hour. They are OD-MLTLs, tuned to bottom out around 50hz.
The drivers are Fostex FE166ES-Rs that I have had laying around for a while. They have VERY limited xmax, so the enclosure was designed to be a compromise between depth extension and excursion, keeping in mind that the listening volume is not going to be very high.
The material is cheap plywood (with voids lol) left over from the fort that was built for orientation. I didn't have access to a table saw, and didn't want to wait to use the waterjet, so I just freehanded everything on a circular saw. A good amount of glue was used to seal up various gaps.
These are basically studies in what happens when you take a pretty good design and excellent speakers and then throw all other 'good build principles' to the wind.
The result is surprisingly good. There is obviously some coloration in the 200-500hz range, but the high end and bass is really quite nice. There is a definite soundstage, and they are very listenable.
I plan to build a 2ft^3 sealed subwoofer to hang on the wall behind these things, and I will waterjet that enclosure so it will be an interesting juxtaposition of high precision vs VERY low precision. It will be nice to have the low end support, though they are very listenable without a sub.
FUN FACT: these are the only speakers I have ever made that are partially painted with my blood
splinters...
Meet the DGAFs:
As the name might imply, these speakers were the result of a late night at MIT. I designed them in HornResp in about an hour. They are OD-MLTLs, tuned to bottom out around 50hz.
The drivers are Fostex FE166ES-Rs that I have had laying around for a while. They have VERY limited xmax, so the enclosure was designed to be a compromise between depth extension and excursion, keeping in mind that the listening volume is not going to be very high.
The material is cheap plywood (with voids lol) left over from the fort that was built for orientation. I didn't have access to a table saw, and didn't want to wait to use the waterjet, so I just freehanded everything on a circular saw. A good amount of glue was used to seal up various gaps.
These are basically studies in what happens when you take a pretty good design and excellent speakers and then throw all other 'good build principles' to the wind.
The result is surprisingly good. There is obviously some coloration in the 200-500hz range, but the high end and bass is really quite nice. There is a definite soundstage, and they are very listenable.
I plan to build a 2ft^3 sealed subwoofer to hang on the wall behind these things, and I will waterjet that enclosure so it will be an interesting juxtaposition of high precision vs VERY low precision. It will be nice to have the low end support, though they are very listenable without a sub.
FUN FACT: these are the only speakers I have ever made that are partially painted with my blood
splinters...Attachments
Try also the drivers described here:
http://www.diyaudio.com/forums/full-range/171707-chinese-taiwan-4-dual-cone-speakers.html
You won't be disappointed!
Ciao!
Just something I have been playing with for the last year. It's a DIY full range 6” unit, the plan is that it shall bee used fro 80Hz and op. This has been the best project that I have been working with in years, and the most challenged by far. Here is some pictures.
Take care
Take care
Attachments
¿Is it a field-coil speaker? I have always wished to do something like that, but as you say it is extremely challenging. Looks promising...
Any particular wisdom on using this ply (e.g. cutting or gluing)? May be a better post for another thread I suppose.
catching up a few days later -
as for working with this specific grade of bamboo plywood -
- take time on your layout for "grain" alignment / matching with highly figured patterns light the Neopolitan stranded
- your tooling cannot be too new or sharp - highest tooth count carbide tipped fine cut saw blades you can afford, and brand new router bits.
- regular wood glue works just fine for me (Titebond Type II or III)
- if deeply rabbeting edges to achieve the effect shown below, handle very carefully, as the top "ply" is very fragile in the long grain direction, but the results can be well worth the effort
These were my first Fonkens with bamboo, and must have taken 50 hrs to get "close enough"
- as tough as bamboo might be, to avoid bruising you still want to use blocks/ cauls etc when clamping with F or Pony type pipe clamps.
- as I'm a lazy sonufabeech when it comes to finishing, I tend to spray a few coats of lacquer, but it can look just as gorgeous with your favorite oil/wax formula.
as for working with this specific grade of bamboo plywood -
- take time on your layout for "grain" alignment / matching with highly figured patterns light the Neopolitan stranded
- your tooling cannot be too new or sharp - highest tooth count carbide tipped fine cut saw blades you can afford, and brand new router bits.
- regular wood glue works just fine for me (Titebond Type II or III)
- if deeply rabbeting edges to achieve the effect shown below, handle very carefully, as the top "ply" is very fragile in the long grain direction, but the results can be well worth the effort
These were my first Fonkens with bamboo, and must have taken 50 hrs to get "close enough"
- as tough as bamboo might be, to avoid bruising you still want to use blocks/ cauls etc when clamping with F or Pony type pipe clamps.
- as I'm a lazy sonufabeech when it comes to finishing, I tend to spray a few coats of lacquer, but it can look just as gorgeous with your favorite oil/wax formula.
catching up a few days later -
as for working with this specific grade of bamboo plywood -
- take time on your layout for "grain" alignment / matching with highly figured patterns light the Neopolitan stranded
- your tooling cannot be too new or sharp - highest tooth count carbide tipped fine cut saw blades you can afford, and brand new router bits.
- regular wood glue works just fine for me (Titebond Type II or III)
- if deeply rabbeting edges to achieve the effect shown below, handle very carefully, as the top "ply" is very fragile in the long grain direction, but the results can be well worth the effort
These were my first Fonkens with bamboo, and must have taken 50 hrs to get "close enough"
- as tough as bamboo might be, to avoid bruising you still want to use blocks/ cauls etc when clamping with F or Pony type pipe clamps.
- as I'm a lazy sonufabeech when it comes to finishing, I tend to spray a few coats of lacquer, but it can look just as gorgeous with your favorite oil/wax formula.
Excellent. Thanks, Chrisb. Oh, and beautiful work on the Fonken.
Tang Band W8-1808 8" Neodymium Full Range
I finished these about 1 month ago.
It was a lot of work to get the finish right on the boxes.
I find voices to be sibilant in this 1.4 cu ft sealed box with a 200W solid state ATI amplifier.
They would probably sound better with a tube amp.
They would probably sound better open baffle, or at least ported.
But I am not going to experiment.
I am selling the drivers because I don't like them in a 1.4 cu ft sealed boxes that I built. I just listed them on Craigslist (Los Angeles and Ventura county).
I am going to move on and build a 2-way with these boxes.
I finished these about 1 month ago.
It was a lot of work to get the finish right on the boxes.
I find voices to be sibilant in this 1.4 cu ft sealed box with a 200W solid state ATI amplifier.
They would probably sound better with a tube amp.
They would probably sound better open baffle, or at least ported.
But I am not going to experiment.
I am selling the drivers because I don't like them in a 1.4 cu ft sealed boxes that I built. I just listed them on Craigslist (Los Angeles and Ventura county).
I am going to move on and build a 2-way with these boxes.
