Projects - JKN 01 Speaker Project
Construction of Raal JKN 01 MTM
This speaker project has been in progress for some time now close to 2 years in fact but finally
construction is going ahead.
I have tried some Ribbon drivers before but was looking for some which could be crossed around 2000 HZ the contenders were R2 and R3. R3 was too expensive and R2 was still in my mind.
I have talked to a guy from Czech Republic and he recommended trying the Raal 140 as it is good. I did check the Raal website see the (pictures) graphs and all was looking good crossing at 1600HZ "well" .I did take the plunge and ordered these drivers and now I'm happy that I did, as I'm really happy with it's performance
- Special FLATFOIL® pure Aluminium ribbon
- Ribbon material: aluminium
SPL VS FREQ.& Horizontal Dispersion
SPL VS FREQ.& Vertical Dispersion
Here is a link for Australian distributor
For Mid/bass I have been recommended to use some of these companies
In the end I decided to go for the PHL 1220 with Raal 140 D15
Here is a link for Australian distributors
WA - Australia
The next step was to find the right design (enclosures.) I did not want to just make a simple box.I was looking for something different. I have to mention that at the same time a friend of mine Mark was after some enclosures for his 3 way design using the same drivers etc. MT enclosure (Raal 140 15D and 1 off PHL 1220)and for his bass he decided to used Peerless. Mark has been contacting Alex from Raal for any ideas. As a matter of fact it turns out Alex is a designer himself and he sent us some of his designs that he has done in the past. We had a look at his designs and it was clear to us that Alex is the man for our projects. Mark had some of his ideas, and let Alex know what he would like. It took some time as it turned out to be a more complicated design than originally planed. I won't explain how Marks 300KG each speakers design came to life. I will concentrate on my MTM 110 KG bookshelf.
Brief summary of my MTM's
(Hi-Fi World April 2009)
The box is constructed from 2 separate Ply's (909 subdue 24mm external and 28 hardwood ply (armor 34f) for internal and bracing. Note that 909 Subdue ply is a specialy made ply used in boating, aero industries and especially used as a soundproof partions' around engines and so on. The 909 ply is basically 2 pieces of 12 mm ply and in the middle a 5 mm wave bar is pressed and glued.
The box is going to be 50 mm thick all around.
Here is the Drawing