My DIY speakers -"J&N"

[Jororaitchev]

The idea of hand-made/ DIY / loudspeakers was born in me, when I saw the model of JBL-tI6K . The design and fabrication of these unique shapes are made by a Danish designer. The pyramidal shape of the speakers is generally denied by the DIYers, or at least for the most part, but I decided at the moment that's my loudspeaker design. If there is interest in the topic, I will continue ;

 

[Blaylock]

Those are gorgeous. Please, do tell more.

 

[Voodoo Rufus]

Yes, go on. I've built my fair share of kit speakers. It's a great hobby, until you have more audio gear than the significant other can handle.....

 

[EarthDog]

I've got a Theil CS 3.7 vibe (or some B&W) with these... moar plz!

 

[Jororaitchev]

Gentlemen, thank you all for your attention and good evaluation of my project, thank you very much!

I will show a few stages in the construction of these speakers, but first their technical characteristics;
The loudspeakers are;
"SEAS"- Excel / Tw-1”, Mw-5”for center 2х 5.5”, Bass-8,5”/ and cross-over parts- "Intertechnik".
Nominal impedance- 8 Ohm.
Range 30Hz- 25kHz.
Characteristic Sensitivity(2,83V/1m)- 87db.
Long Term- 110W.

I'll show you, how I made these speakers, supported with photos and with detailed information as possible. This project is a long time ago and some of the stages during their construction , I can not show them - I do not have the necessary material, but what is available, I suppose will be enough to provoke your interest.
At first, I had to figure out how to bend MDF plates. In the internet now has a very detailed material on how this process is being carried out with complicated multi-operative press machine, but 2009 this information was scarce and irrelevant to me because, its clear I can not make a similar device at home.
to be continued...

 

[Jororaitchev]

For this purpose, I made this "Home Matrix" for the front speakers;




and for the center ;

On these matrices I bended 8 layers of 4mm MDF. The adhesives I've used will be discussed at a later stage;




The filters are positioned in this way;



My initial idea was, for a bass speaker 6.5 ", but once I assembled the pilot model and measured the internal volume of the cabinet, found that I had enough reserve even for a 10" speaker. I decided at this stage to use 8.5 ".
This is the first option;


The final decision;

After veneering the next steps are, to make the desired color , and the following finish manipulation , spraying with high quality automobile acrylic lacquer;



to be continued

 

[Blaylock]

Wow. That truly is impressive. I'm an amateur woodworker and this project raises many questions. For starters, what is the purpose of the foil and how did you get your seams so flawless?

 

[Jororaitchev]

Wow. That truly is impressive. I'm an amateur woodworker and this project raises many questions. For starters, what is the purpose of the foil and how did you get your seams so flawless?

I am very glad that you are interested in carpentry! I am an electrical engineer - High Voltage, carpentry is my hobby, but I made good money from it - a fact!
From the position of my 62 years, I think I have something to teach you.
Joro
P.S.
I will explain everything to you, just a little patience, please, let's wait for more questions!

 

[NiHaoMike]

For starters, what is the purpose of the foil...

Most likely electrical shielding, some digital amplifiers have the speaker outputs at a common mode of about 50Vpp at 400kHz or so whenever the amplifier is operating (not just when playing audio), which can be problematic for particularly sensitive electronics very close to the speakers or (unshielded) speaker cables.

BTW, the TI TAS563x are known to have that problem when used in a "reduced inductor size" config, the newer TPA3255 (currently the best single chip amplifier out there) uses a tweaked modulation scheme to mitigate that.

 

[Jororaitchev]

This aluminum foil is to not to be glued the layers in bending, only for this is.

Post magically merged: Feb 5, 2022

.... and how did you get your seams so flawless?

The veneer I use in Bulgaria is known as "Birds of Maple", in the world is also known as "Bird's eye" . We reach the moment of very specific activity - veneering with natural veneer. When veneering panels, details is in one plane, there are no problems. There is only a requirement - the person who collects the individual pieces has good skills, the rest is completed by the pneumatic press.
When we talk about a complex shape, our immediate association is for "Vacuum press", but there is a limit to the thickness / height / of the workpiece. If we are talking about veneering of a flat surface with motifs on the surface - it does work, but if it is another massive form dont.
Due to the complexity of the process, i will pay close attention to it. My technique is complex, risky on a large scale and I definitely do not recommend it to enthusiasts with little experience! A natural veneer can bend tangentially or radially, usually masters prefer to work in just one direction - for less headaches. In my method of processing, I use both bending directions simultaneously, but add a third diagonal bending.
The other main problem is the adhesive with which it sticks the veneer, it is polychloroprene, this glue does not allow you to move the veneer, once touched to the base there is no other chance-stays there. If you try to move it, you will break the veneer at the moment, and when we talk about "Birds of Maple" with a price over 40 EUR, the feeling it's not pleasant!
I will explain my technique for cutting veneer before gluing it.
On the finished cabinet of the loudspeaker, from " India paper" / she is the closest with the veneer / I make the templates that should lie perfectly on the base. The problem is in the wrong shape, the veneer after gluing in one part, changes his shape, although everything has previously been matched perfectly. It requires a lot of attention, patience, and proper judgment, which part should squeeze, otherwise balloon spaces are created, which are very difficult to correct without being visible later. Sometimes, depending on the type of veneer, moistening helps, but this action also requires judgment with experience.

 

[Voodoo Rufus]

Wow. Excellent work. I might have to dig up my speaker pictures from a year ago and post them.

 

[Jororaitchev]

Wow. Excellent work. I might have to dig up my speaker pictures from a year ago and post them.

Thanks!
Come on! My photos are 10 years old/ this is was my first project/.

 

[Jororaitchev]

After veneering the next steps are, to make the desired color , and the following finish manipulation , spraying with high quality automobile acrylic lacquer;

To obtain the desired gloss, after about the tenth layer, the surface after each new one subsequent layer (total about 20-25) is polished, the result is this end product;

Post magically merged: Feb 8, 2022

A few more photos on the topic;

A flirtation with the light, checking the quality of veneer and painting;

 

[Jororaitchev]

Meet with my logo, please! The name of the my loudspeakers - "J&N" are the initials of Joro/ my nickname / and Nelly/nickname of my wife / and this is ours logo.

Some think," It looks like the J and N are giving each other a high five". Yes, that's right, it's been 40 years together!
in reality;

 

[EarthDog]

When I go back to separates/start on the media room, I want something like these fo sho...just incredible!!!

 

[Jororaitchev]

When I go back to separates/start on the media room, I want something like these fo sho...just incredible!!!

Maybe something like this room?

 

[Jororaitchev]

I will show you one of my projects I had to change it , basically right at the very beginning - the back speakers ;
We all know, what is the ideal shape for the speakers- sphere. For technological reasons, it is difficult to do, especially with three tape loudspeakers. I strive to make the second most effective form - the egg. To begin with, I schematically design this way. I calculate the approximate volume, how do I find the right volume, will show you later in my project .
The loudspeakers are "SEAS"- Excel T25CF002 ", W18EX001- 6,5" . Everything is handmade, no "CNC" machine is used.
First option;

Тhe internal structure of the cabinets;