Full-Range Dutch ESL Project File translated - Page 4 - diyAudio
Go Back   Home > Forums > Loudspeakers > Planars & Exotics

Planars & Exotics ESL's, planars, and alternative technologies

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 17th July 2010, 03:01 AM   #31
diyAudio Member
 
Join Date: Nov 2005
Location: Southern Germany
Bolserst,

Regarding tensioning rate two things need to be considered:

1. If you wind several wires to the gig, some will be wound loose and some more strong. If you stretch the gig by about e.g. 2 % it could be that the more loose wires wont be stretched to plastic deformation savely.
2. If you choose an appropriate copper condition, it will harden when exceeding a certain stretch ratio. I am utilizing this effect.

You are right, stretching by 10 % isnt easy and i experienced cracked wired as well. I took me some investigations and finally i found the copper quality and jig design to fix it.

As mentioned in the previous post wire stators are a very thankful design for ESL. Having solved some problems manufacturing is reproducable, reliable and low cost without compromising quality.


BTW: Bolserst, somewhere i read some thoughts of you, that an segmented wire panel should be more efficient than a perf stator.

You are absolutely right. In a nonsegmented panel (flat or bended) the amp will see full capacitance of the panel at any frequency. In order to provide bandwith up to 20000 Hz, you need to reduce stepup ratio. In additon a non-segmented panel will increase sound pressure with increasing frequency, so you need to "burn" energy in a passive network to linearize frequency response.
I did some comparisons between segmented and non-segmented wire stator. In order to target identical high frequency limit and identical lowest impedance of at least 2 ohms, the stepup ratio needed to be reduced from 1:160 to 1:100, which is a significant difference. At lower frequencies, where effiency is most important for ESL-designs, the segemented panel is more efficient by about 4dB at identical input level.

That perf stators are more efficient is imo on of the most famous rumours regarding ESL and possibly its due to the ML hybrid designs.

Capaciti
  Reply With Quote
Old 17th July 2010, 08:56 AM   #32
diyAudio Member
 
Join Date: Oct 2007
Location: melbourne
hi all
great thread keep it coming !

ok so far we have
1 , wire .... any pvc insulated from 1mm to 3mm od inc insulation with solid being best

2 ,segmented design makes for an easyer load and better dispersion

3, higher the better with floor to ceiling best on panel size

4, keep wire spacing similar to d/s spacing for best sensitivity

5, for full range seperate sections are best so on a panel size of say 1800mm x 360mm you would split it in half and have 1x 1800mm x 180 doing bass and 1x 1800mm x 180mm doing mid/high side by side (like capacity panels )

6, d/s spacing for full range ???

7, ds spacing for hybrid = .8 to 1.5mm depending on how accurate your panels are built

8, diaphram ,thinner is better with 3 to 4 micron ideal

9, stretch your wires between 2 to 10% depending on wire type and jig

please add to my list or point out any mistakes

cheers sheafer
  Reply With Quote
Old 17th July 2010, 09:56 AM   #33
diyAudio Member
 
Join Date: Nov 2005
Location: Southern Germany
Slr 5000,

most agreed, but:

4. always keep wire spacing as close as possible, even at larger D/S and make closer than 50% open area down to 30%
6. D/S Spacing for fullrange not more than 3mm. More will kill sensitivity significant and if you exceed a certain excursion low frequencies sound uncontrolled and boomy. A fullrange with area about 0,5qm will play loud enough if fundamental resonance is best controlled. Most designs suffer pressure due to resonance peaks consuming excursion without the impression of playing loud.
10. For lowest distortions and highest level output build your design as symmetric as possible. e.g. the D/S spacing of both stator halfs should not vary more than 0,1mm !!!!! for e.g 2,5mm D/S spacing. You can check your accuracy when looking into the finished ESL. If the membrane looks bended towards one stator its bad if it looks perfectly plane - bingo ! A worse symmetric stator design will cause the mebrane to bend up to 1mm. Easy to understand that this kills level. 2,5mm minus 1mm is just 1,5mm excursion left !!!

Capaciti
  Reply With Quote
Old 17th July 2010, 10:36 AM   #34
diyAudio Member
 
Join Date: Oct 2007
Location: melbourne
hi capacity
re the segmentation of the panels
the panels im currently building are modeled visually on your element x2 which i find most beutifull and have inspired me to make a wire stator esl

each panel is 2 x sections 1800mm high by 180mm wide side by side
i would like to run both sections full range down as low as possible and then fill in the bottom end with a sub

is there a theoretical ideal segmentation for this size of panel section for full range eg 1800mm x 180mm
each panel section will have 40 wires with a 2mm centre to center spacing and a d/s of 2.5mm

i was thinking 4 sections of 10 perhaps
  Reply With Quote
Old 17th July 2010, 10:40 AM   #35
diyAudio Member
 
Join Date: Oct 2007
Location: melbourne
[QUOTE=slr 5000;2246065]hi all
great thread keep it coming !

ok so far we have
1 , wire .... any pvc insulated from 1mm to 3mm od inc insulation with solid being best

2 ,segmented design makes for an easyer load and better dispersion

3, higher the better with floor to ceiling best on panel size

4, keep wire spacing close as possible down to 30% spacing for best sensitivity

5, for full range seperate sections of the same size are best so on a panel size of say 1800mm x 360mm you would split it in half and have 1x 1800mm x 180 doing bass and 1x 1800mm x 180mm doing mid/high side by side (like capacity panels )

6, d/s spacing for full range max 3mm for minimum distortion

7, ds spacing for hybrid = .8 to 1.5mm depending on how accurate your panels are built

8, diaphram ,thinner is better with 3 to 4 micron ideal

9, stretch your wires between 2 to 10% depending on wire type and jig

10, make both stator halves as symetrical as possible ,no more than .1mm variation for lowest possible distortion

please add to my list or point out any mistakes

cheers sheafer[/

ive edited the above with capaciti revisions

Last edited by slr 5000; 17th July 2010 at 10:46 AM.
  Reply With Quote
Old 18th July 2010, 03:09 AM   #36
diyAudio Member
 
bolserst's Avatar
 
Join Date: Jun 2005
Location: Fort Worth, Texas
Quote:
Originally Posted by Capaciti View Post
If you wind several wires to the gig, some will be wound loose and some more strong. If you stretch the gig by about e.g. 2 % it could be that the more loose wires wont be stretched to plastic deformation savely.
Hi Capaciti,

This is a very important point, and a detail I left out. Thanks for bringing it up.

Like you say, when winding the stator wires back and forth between pins it is very difficult to get them all wrapped with identical tension. What I do before marking the starting point for the 2% stretch is pull tension until any slack or looseness is removed from every wire. Then, mark this as the length for starting the 2% stretch. Otherwise, it would be possible to end up with some wires that did not get stretched enough to reach the plastic deformation zone. With this technique, every wire is stretched a minimum of 2%.
  Reply With Quote
Old 18th July 2010, 07:12 PM   #37
mavric is offline mavric  United States
diyAudio Member
 
mavric's Avatar
 
Join Date: Nov 2009
Location: some place nice
Default wire

Where or whom can you purchase the wire? As well, there are the resistors and values. can you kindly send a pic with 10 meg or higher to my email, as you know a picture is worth a thousand words.
The gig is and a been a problem, i was using mdf, but as i have used it for so long, i know it will splt, any suggestions?
You are obviosly a professional. I love to try different things in audio. Curious has always been my reply, so is there anyway to get better, more high res pics from your build? I did mine as step by step, still learning, want more. PM me for an email with better pics please. Other wise,have a good weekend, Mavric
__________________
The only true wisdom is in knowing you know nothing.
A wise man does not need advice and a fool won't take it.

Last edited by mavric; 18th July 2010 at 07:26 PM.
  Reply With Quote
Old 19th July 2010, 09:03 AM   #38
Calvin is offline Calvin  Germany
diyAudio Member
 
Calvin's Avatar
 
Join Date: Nov 2004
Location: close to Basel
Hi,

the electrical openness depends very much on the thickness and the electrical behaviour of the insulation material. One cannot simply say PVC has much lower impedance and higher capacitance than air. It depends on which derivative, colour/ingredients and manufacture of the PVC. Electrical parameters may vary considerably. With regard to efficiency of the stator construction and field homogenity thinner insulation and smaller distances are preferred.

I disregard the above claims about segmented panels beeing more efficient than punched metal sheets. Theory and practise tells different. At least do I have to see the wire stator panel that beats a decent metal sheet stator in dynamic range at same input voltage range. Sonically the larger membrane area shows can be heard as a more dynamic play.
The transformation factor of the audio tranny is a direct measure of the panel´s efficiency. It translates the low value input voltage to the needed high value drive voltage.
In other words, the drive and polarizing voltages needed for a certain SPL are a direct measure for the efficiency of the panel. The lower those voltages the higher the panel´s efficiency. Typical values for wire stators are >1:75 and Vpol of >3kV, while metal stators may only need values of 1:50 and Vpol of 1.5kV. Regardless of the stator construction will a voltage driven ESL panel need some equing. This always costs on efficiency. It doesn´t matter though where I spoil the energy. Be it external eq-circuitry on the primary side of the audio tranny or be it on the secondary side ´within´ the panel. The segmenting resistors or -differently named- equalizing resistors of a segmented wire stator waste efficiency equally well as a notch-filter on the primary side.
The disadvantage of all components on the secondary side is the increased transformation factor of the audio tranny, which should always be as low as possible.
The segmentation reduces the capacitance towards higher frequencies by reducing the active stator area/membrane area. So we have a serious loss of active membrane area, hence loss of soundpressure level which is countered by a higher transformation factor of the audio tranny. But while the active membrane area may be reduced to 1/4th or less (meaning a SPL-loss of -6dB or more), the difference between a transformation factor of 1:50 and 1:100 translates to just +3dB. The impedance rises by a factor of 16 in this case, which means a slightly better efficiency wattage-wise, but since we assume an stable amplifier, that is constructed as a voltage source, only the voltage-efficiency is of importance. In this regard the non segmented metal sheet Stator is far better.
At lower frequencies the active stator area/membrane area is the same and so is the capacitance value. Therefore similar transformation factors (hence drive voltages) should be needed.
As practise shows (see Matthis) metal sheet stators still reach the same SPLs with lower transformation factors and voltages, which means that the metal sheet stator shows better efficiency even in the lower freq range. Admittedly it´s difficult to compare matters when dimensional differences of the constructions in the range of tenths of millimeters already have greater influenceon the results than the conceptional differences.

jauu
Calvin.

ps: One of the biggest advantages of low voltage ESL designs is the reduced voltage stress (voltage-gradient stress) which means less aging and higher safety margins and which allows the usage of better components.
  Reply With Quote
Old 19th July 2010, 01:09 PM   #39
diyAudio Member
 
Join Date: Nov 2005
Location: Southern Germany
Why should a perf metal stator be more efficient than a non-segmented wire stator, when both having identical area, D/S spacing and open area ???

Capaciti
  Reply With Quote
Old 19th July 2010, 02:10 PM   #40
diyAudio Member
 
bolserst's Avatar
 
Join Date: Jun 2005
Location: Fort Worth, Texas
Quote:
Originally Posted by mavric View Post
Where or whom can you purchase the wire? As well, there are the resistors and values. can you kindly send a pic with 10 meg or higher to my email, as you know a picture is worth a thousand words.
The gig is and a been a problem, i was using mdf, but as i have used it for so long, i know it will splt, any suggestions?
Hello Mavric,

Unfortunately I don't have the spare time right now to put together a complete step by step build guide. In fact I'm away on business right now. It may have to wait til retirement

Wire Stretching Jig strength:
If I remember correctly, it took about 30 lbs of force to stretch a single 22AWG wire, 50lbs for 20AWG. So, if your panel has 80 wires and you want to stretch them all at once it will need to withstand 2,400 lbs of force for 22AWG and 4,000 lbs of force for 20AWG. Your jig will need to be made out of metal to withstand this magnitude of force. The end blocks holding the ends of the wire will need to handle the force too. Each pin needs to handle the force for stretching 2 wires. If you want to stretch your wires you will need to build a metal jig. I used 1" x 4" structural steel tubes for the frame and 6061-T6 aluminum 0.5" x 2" for the end blocks. I got the steel from a local supplier and the aluminum from online metals.
Rectangular Tube - Norton Metals eCommerce
Order Aluminum 6061 Rectangle in Small Quantities at OnlineMetals.com

Wire sources
There are many online sources for 20-22 gauge solid copper hook-up wire.
Mouser Electronics - Electronic Component Distributor
Allied Electronics ? Electronic Parts and Components Distributor
Wire & Cable: Red/Black Zip Cord high strand count bonded wire. Stranded & Solid Hookup Wire UL 1007. PTFE Coated Stranded Wire for high temperature and abrasion resistance. Magnet Wire for winding coils ballasts and motors. Power Wire (Monster Type)
PVC Products - Jaguar Industries

For experiments and smaller test panels, you can get 100 ft rolls of 22AWG at your local Radio Shack.

Recommendation
For anybody contemplating building stretched wire stators, I would recommend starting small.
Try building a 4" x 12" panel to learn the techniques involved, and to try out different materials and adhesives.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Building / Designing my first full range esl electros Planars & Exotics 1 2nd June 2010 03:06 PM
.slb file (translated library file)...! spice freak Solid State 0 28th October 2008 03:20 PM
Full range ESL vs ESL + sub Jacobus Planars & Exotics 18 24th September 2007 02:50 AM
Dutch ESL builders attention...part ESL for free Bas Horneman Swap Meet 10 14th June 2005 07:54 AM
Help in designing a full range ESL transformer PLEASE! mwmkravchenko Parts 11 8th June 2005 12:27 PM


New To Site? Need Help?

All times are GMT. The time now is 11:47 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2