Planars, Classic drivers OB or others ?

[Eldam]

Geraldfryjr,

The frequency curve of your little planar is very good ! The flater is yhe one after electronic correction ? It seems a good deal because it's easier to flat a curve for distorsion than to bump it (like OB below 300 hz) or less width planar à la Infinity G&B rd75. Do you use a bass box below 100 hz or good enough like that at short distance ?

I plan first if not expensive to try a little panel to test esl sound in domestic room. To have cost effective, I have to go less the cost of a magnet ribbon planar like (the cost effective) B&G Neo 10 (100 euros). You say 20 dollars. I bet . The problem here in France who take the direction of Midle-Age is to source Dupont&Nemours 3 microns film and coating materials ! I see no brands in my countrie makes planar, just a fanatic guy who make an artisanal plasma tweeter ! But Ebay maybe helps me...

 

[geraldfryjr]

The ripples in the curves are caused from reflections of the nearby monitors and such on my desk and the two curves are just to different smoothing factors.

Basically they are extremely flat and I only used the shelving eq's on my mixer to act as a type of crossover system.
All else is pretty much flat and straight forward.

I have posted in a past thread of a more accurate curve of just the panels with no reflections mucking up the curve.

Here is a thread that is a bit more detailed,

A Desktop ESL Build

Here is a copy of this thread,

~~~~~~~~~"I found some FR charts today of the system.

The first chart just shows the overall response of the system in RED and the ESL in GREEN.

The next two charts are as follows,

The BLACK line represents the test signal and is set to drop the extreme lower frequency as the excursions with little woofer were quite large.

The BLUE line is the overall combined response.

The GREEN line is just the ESL.

And the RED line is the woofer by itself.

Had this test been in a more open area the FR curve would have been ruler flat.
The one thing that i do like about testing this way is that it shows me exactly what I was hearing.
On the previous chart the bottom line is the THD and the sound was incredibly clean and jaw dropping as I could not pinpoint hearing either driver.
The sound appeared to be coming from one single point even when a frequency sweep test was done.

I was quite amazed for such a simple little setup as there is always room for improvements (maybe !!).

The test was done the HOLMImpulse and a Dayton measurement microphone through a Mackie32-8 mixer and a Gina24 sound card.

The last chart was done with a Peavey PVM520TN.
It is a large diagphram dynamic microphone an has seen its days of use but it is still very flat but does roll off at about 15Khz.
I mostly use it for Bass and high SPL measurements.

I think I have some charts calibrated in SPL db using REW5 and if I find them I will post them as well."~~~~~~~~~~~~~~~~~~~~~~~

Here is the thread detailing the build of my newest Segmented Design,

A Segmented Stator Desktop ESL

This design was inspired by the discussion we had in this thread,

http://www.diyaudio.com/forums/plan...tor-esl-simulator-esl_seg_ui.html#post2908293

Yes , it has been difficult to source Mylar these days although not impossible.
The Type I have is .25mil (6um).
It is the same stuff you use too make Magnetic Planar's as well.

Beside the paint and electronic's it may be the one component that seems cost the most although shipping shouldn't be as bad on your side of the pond.
It is made only in Germany somewhere anymore.

Typically many have found it on Ebay for various prices that aren't to bad.
But at least it can be found in larger widths as well,as mine is only 12" wide material.

To answer your question, It is the Stator that is segmented and not the diaphragm.

I have had the thought of a Segmented Diaphragm recently but I am not sure if it will work well, or even, if at all.

I am still working out some details in order to give it try when I start testing the my new model.
Theoretically it seems that it should work, But we shall see.

I too will able attempting a Plasma tweeter some time soon as well !!

Enjoy !!

jer

 

[geraldfryjr]

Here are a few more pic's of my small builds,

http://www.diyaudio.com/forums/planars-exotics/158115-material-esl-2.html#post2075441

And my system and MicroESL,

http://www.diyaudio.com/forums/planars-exotics/158115-material-esl-2.html#post2074212

http://www.diyaudio.com/forums/planars-exotics/158115-material-esl-2.html#post2076459

This thread was from a very successful build from a complete Newbie Mavric and was Inspired by CharlieM's design.
The build was assisted by Charlie as well.
I have heard these panels and they sound fabulous!!!
He had started another thread showing many pictures of the build from beginning to end as well.

But like I said, They can be made any size you choose build.
And the choice of materials you choose will determine the overall cost depending on how resourceful you are.

When calculating your build keep in mind that you want no less than about 40% open area to about 55% or so of maximum open area.

The plastic grid I used is $10 for a 2'X4' peice and widnow screen is less than $.25 per square foot.
I used Licron as my coating and this is not cheap but for my very first panel I used graphite.
There are many other types of DIYcoatings that works as well and cost next to nothing to make.

I spent about $200 trying different materials only to come up with a panel that was actually dirt cheap to build and the performance was not lacking in the slightest what so ever!

For my Stator coating I use Acrylic Enamal Spray Paints and my study can be found here,

http://www.diyaudio.com/forums/plan...tric-coatings-fact-fiction-2.html#post2893839

This whole thread is very informative and should be read from start to finish.

Here is another great thread on Coatings and some more details about my little panels and how the are constructed.
Very long and another great read,

http://www.diyaudio.com/forums/planars-exotics/109789-esl-diaphragm-coating-7.html#post2142822

http://www.diyaudio.com/forums/planars-exotics/109789-esl-diaphragm-coating-8.html#post2160477

Here are some of the other Frequency response charts that I had mentioned earlier in this same thread,

http://www.diyaudio.com/forums/planars-exotics/109789-esl-diaphragm-coating-8.html#post2162068

jer

 

[geraldfryjr]

Addum to the last post,

Those were done with the Peavey 520TN microphone and typically they actually show the response of that particular microphone, as they are very flat as I have found out after when I got the Dayton Measurement microphone that I now use.

I had a response test that I did that showed a panel to be ruler flat even with the Peavey mic.
I had taken extra measures to dampen the room with acoustic treatments from reflections, But those post's as well as most of that thread got erased for some reason at that point in time, I don't know what the cause was or what the details of the issue were for the moderation to happen but they are now gone.


Jer

 

[Eldam]

Geraldfryjr...A big thank to you for all the explanations and links.

I found the link about the 6u mylar on the DIY ESL 's site of Jazmann (thanks for this didactic site, very easy to understand, even for a french). Strangly the most difficult to source is maybe the classical stator, because I don't find a "click & mortar" supplier here. And understand now that the % openess and thick is not choose by chance ! If the openess wouldn't be so important I believe than flat wired ribbon used for speakers cables or air self could match... but air pessure between such stators and diaphragm...herk ! Maybe wired in horizontal position... 2 cm depht stator stacked each others with one air self ribbon but 99% openess because 0.001 mm thick seen by the diaphragm. Is it a silly idea ?

By the way you conviced me that the narrow and wired segmented sator way is certainly the better in regard to my own taste (larger sweet pot), easier integration with the room and I believe with hybrid but in a two box speaker to avoid vibration for the planars... easier with little planar.

We can imagine too that under 100 Hz you can have the bass box (OB, LT, others...) at 3 or 4 meters of your listening position and the little planars at 1 meter or less : gently set up for sweet spot and a near headphone philosophy à la Linkwitz 's Pluto (that he puts near the chair for suround... or main speaker...if the WAF agree and the time alignement of the DSP agree too. My understanding is that the bass are not beaming under 80 Hz. the quality of the 80 to 150 hz area is certainly a problem in such a project. Maybe 48db/octave cut would help ?

I have to find near me an audiophile who have a Quad ESL to have a listening benchmark reference...
It seems that I have a new project now and not too expensive...super !

Thank you again all.