Soap bubble speaker - 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 15th January 2007, 03:39 PM   #1
APi is offline APi  Finland
diyAudio Member
 
Join Date: Nov 2004
Location: Oulu
Default Soap bubble speaker

Have you ever put anything that has static charge next to a stream of water? Yes - The water bends.

How about doing a electrostatic speaker that has a ultra thin soap bubble as a diaphragm? It should work ok and has extreme high efficiency.

My idea how to test this is to build a plate that has many small holes. It forms a waterfall kind of plate where soaped water or similar is falling slowly down and thousand pieces of water films are formed in holes. These soap films stay because new liquid is fed all the time.

The plate can be a metal grid that has high voltage and it is between stators. Should work, eh. Even curved planars are possible to be build this way.
  Reply With Quote
Old 15th January 2007, 05:23 PM   #2
diyAudio Member
 
I_Forgot's Avatar
 
Join Date: Jan 2005
Location: Phoenix, Az.
THAT is an interesting idea!

I can foresee all sports of problems, but that's what will make it fun to build!

A little glycerin or detergent in the water will make it slightly conductive.

Maybe the center of the speaker will be a perforated panel with the water/soap supply flowing down over it. The small bubbles in the perforations will produce the sound. So you'll have an array of thousands of tiny bubbles (Don Ho?) making the sound. The self resonance should be very high frequency. The only tension on the bubbles will be the surface tension of the liquid. Since you're operating below resonance the response should be very predictable.

I suspect it might be difficult to get the water to flow and form each bubble. You might need something to wipe the bubble-frame periodically to replace popped bubbles.

Definitely an interesting project!

I_F
  Reply With Quote
Old 16th January 2007, 03:42 PM   #3
APi is offline APi  Finland
diyAudio Member
 
Join Date: Nov 2004
Location: Oulu
Yes. You propably need some kind of wipening mechanism to constantly build new soap films since you cannot trust that they stay forever. It is possible if you have a motor moving perforated panel slowly against something etc. Silent? Challenge.

It would be good if water drops in the perforated panel could automaticly build and keep thin film in every single hole but that might be hard. We donīt want a thick noisy waterfall over holes spoiling efficiency!

So what to do? Any ideas?

P.S. Soap film can be far below 1um. Good efficiency. No need for audio transformer?
  Reply With Quote
Old 16th January 2007, 08:09 PM   #4
diyAudio Member
 
Join Date: Nov 2005
Default Bubbles ???

There is a song about such a speaker: "I'm forever blowing bubbles" !!!

Good luck !!!
  Reply With Quote
Old 16th January 2007, 08:39 PM   #5
diyAudio Member
 
Join Date: Sep 2006
Try it!
  Reply With Quote
Old 16th January 2007, 09:28 PM   #6
diyAudio Member
 
Join Date: Aug 2006
Fascinating idea. I might just have to try it one of these days (when I have finished my current revision of my stereo).

Quote:
Yes. You propably need some kind of wipening mechanism to constantly build new soap films since you cannot trust that they stay forever. It is possible if you have a motor moving perforated panel slowly against something etc. Silent? Challenge.
If you have a vertical disc of perforated material, with only the top of it between the stators, you could rotate it through a 'bath' of water. You will end up with a huge box though, and you have to insulate everything very well. You can alter how much water is left in the holes by varying the position of the stators (towards/away from the bath).

The only problem that I can see with this is that the disc will be unsupported around the edge, possibly causing it to flex.

James
  Reply With Quote
Old 16th January 2007, 09:40 PM   #7
diyAudio Member
 
Join Date: Sep 2006
I just tryed it quick. If could not get any sound, i think the voltage has to be very high. I think i had about 2000V. I tryed with a laser driver but it just arced to to bubble and poped it. I will try to get higher voltages some time.
  Reply With Quote
Old 17th January 2007, 08:34 AM   #8
APi is offline APi  Finland
diyAudio Member
 
Join Date: Nov 2004
Location: Oulu
I thought different ways of building soap bubbles that last long enough.

One of the easiest way (in theory) would be a a kind of wide "bicycle chain" that rotates slowly. Lower roller is inside a soap water pool and upper in the air. When a chain rise from the pool soap films are formed between each horizontal rod in the chain. No need for a water pump.

The chain goes up between stators and down behind them.

Horizontal rods are made of metal and wide enough for the whole panel. Unfortunately you cannot make curved panel this way.
  Reply With Quote
Old 17th January 2007, 11:56 AM   #9
diyAudio Member
 
Join Date: Aug 2006
ak_47_boy,
Did you charge the bubble? If so, how did you drive the stators? If not, was the 200v modulated? if not, then there would have been no sound.

APi,
I like that idea- it is better than the rotating disc.

James
  Reply With Quote
Old 18th January 2007, 09:00 PM   #10
diyAudio Member
 
Join Date: Sep 2006
I just stuck an output transformer backwards, played music, stuck one wire in the water and the other i brought close to the bubble. I also tryed attaching a piece of tin foil to the lead close to the bubble. Maby there has to be a bias supply ect. just like a esl.
  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
Onix & soap needs a re-cap fatmarley Parts 28 7th December 2013 09:07 AM
SOAP preamp PCB,s zei Group Buys 19 11th May 2009 10:26 AM
Horn mouth bubble size MaVo Subwoofers 1 25th February 2009 12:59 PM
Output of Onix Soap PS kptseng Solid State 2 16th December 2005 01:12 AM
The Bubble for BG Ribbon Tweeters TheoM Multi-Way 0 9th February 2004 05:20 AM


New To Site? Need Help?

All times are GMT. The time now is 03:55 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright Đ1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2