Ribbon headphone design - Page 2 - diyAudio
Go Back   Home > Forums > Loudspeakers > Planars & Exotics
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

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 14th May 2017, 05:59 PM   #11
jcx is offline jcx  United States
diyAudio Member
 
Join Date: Feb 2003
Location: ..
true ribbons are only fixed at the ends, the sides are free - but practical tolerances means there's a gap which lets lower frequency to leak from front to back, killing the low frequency response

also ribbons are very low R - practical ribbon tweeters come with a step down trnasformer built in - way to heavy for on head wear


with all the physics, engineering against you, either learn it well enough to see the problems

or try cheap fast experiments where you can make all the parts at home; superglue, dremel tool, conductive copper tape...

if you superglue the magnets to phenoic or pcb base material you can remove them for later experiments with acetone

Last edited by jcx; 14th May 2017 at 06:02 PM.
  Reply With Quote
Old 14th May 2017, 07:29 PM   #12
urmom is offline urmom  United States
diyAudio Member
 
Join Date: Apr 2016
Quote:
true ribbons are only fixed at the ends, the sides are free - but practical tolerances means there's a gap which lets lower frequency to leak from front to back, killing the low frequency response
Low frequency deficits are usually much less of an issue with headphones and my push pull suggestion should help with this no?

Quote:
also ribbons are very low R - practical ribbon tweeters come with a step down trnasformer built in - way to heavy for on head wear
I never understood the issue with the low impedance of ribbons and planars, an active current source buffer could drive low impedance loads with ease, it's really a non-issue.

Quote:
with all the physics, engineering against you, either learn it well enough to see the problems
That's why I'm here asking you lovely folks for your wisdom The internet has nothing on you guys

Quote:
or try cheap fast experiments where you can make all the parts at home; superglue, dremel tool, conductive copper tape...
You may have a point here but my assumption in this case is that ribbons are simple enough to not screw up with a reasonable pre-made structure such as the bracket in my pictures, I don't want to skin a cat twice. Am I wrong?

Last edited by urmom; 14th May 2017 at 07:32 PM.
  Reply With Quote
Old 14th May 2017, 10:51 PM   #13
jcx is offline jcx  United States
diyAudio Member
 
Join Date: Feb 2003
Location: ..
Default Uin Engineering programs are the fastest way to get up to speed

if not guided by deep relevant engineering knowledge of the domain then yes you are likely wrong

not saying you can't self educate, but in industry someone might expect even a Masters with EE, Mechanical, Acoustics courses and a few years of industry experience to expect much progress

if you go the empirical, experimental route you should expect dozens, hundreds, possibly thousands of preliminary, throwaway experiments before you build the knowledge to even begin to picture "prototypes"

read about Thomas Edison for a look into the work needed without good theory, practical engineering knowledge to leverage
Edison even hired actual experts such as Nicola Tesla to improve his generators


go for simplest “first sound” experiment – learn how to cut, fixture, make electrical connection to your foil
figure out, make a fast, cheap disposable try at how to hold magnets and foil, interconnect all together
make another, and again, and again...

drive it with a PA and series power R to keep the amp safe

learn how much current destroys the foil

get an idea of the SPL, frequency tilt

think it over, make a “better” 2nd attempt – did you actually get better – do you have the tools, know how to make the relevant measurements?
  Reply With Quote
Old 14th May 2017, 11:51 PM   #14
urmom is offline urmom  United States
diyAudio Member
 
Join Date: Apr 2016
I thought the main variables with ribbon are foil thickness, geometry, and current. What sort of other variables do I need to watch out for?
If I'm going to make so many prototypes like you suggest, would strong plastic be rigid enough to experiment with? Metal is darn expensive to order.
  Reply With Quote
Old 15th May 2017, 12:36 AM   #15
jcx is offline jcx  United States
diyAudio Member
 
Join Date: Feb 2003
Location: ..
Default copying something that exists - sometimes practical - de novo design...

...is a whole different deal

I don't know any true ribbon headphone - which argues for their being impractical

fabrication of parts, fixtures to make the parts, fixtures to align the parts, machining, cutting, drilling, crimping, gluing... turns out to be hard problem even if you knew the best dimensions of everything

and right now it sounds like you have no idea of motor design or acoustics that would let you even make a guess of what would make acceptable headphones with true ribbon transducers

my only somewhat informed guess is that while you can make sound with a ribbon, a headphone sized, wearable ribbon is unlikely to give even conversational level SPL even at high mids, much less lower frequencies


I expect electrostatic headphones are best entry diy build for the sound quality - but hard to recommend on safety grounds
  Reply With Quote
Old 15th May 2017, 01:40 AM   #16
urmom is offline urmom  United States
diyAudio Member
 
Join Date: Apr 2016
Quote:
I don't know any true ribbon headphone - which argues for their being impractical
Probably due to the low impedance inherent to them. It's easier to get planars at higher impedance.

Quote:
my only somewhat informed guess is that while you can make sound with a ribbon, a headphone sized, wearable ribbon is unlikely to give even conversational level SPL even at high mids, much less lower frequencies
There's other threads where people have done it and claimed good results, including bass. Here is one example Ribbon or planar headphones


Quote:
fabrication of parts, fixtures to make the parts, fixtures to align the parts, machining, cutting, drilling, crimping, gluing... turns out to be hard problem even if you knew the best dimensions of everything
It's pretty easy to CAD up a design and get it printed, no need for drilling, machining and all that.

The bracket design I posted earlier only requires a few screws to assemble the whole driver, no glue or fiddling required which brings me back to the question, is hard plastic sufficient enough for a ribbon suspension structure? It's light, cheap, and non magnetic.
I imagine it might absorb vibrations though I'm not sure.


Quote:
and right now it sounds like you have no idea of motor design or acoustics that would let you even make a guess of what would make acceptable headphones with true ribbon transducers
Certainly true which is why I posted the thread. I'm always hungry for knowledge and unfortunately on the subject of audio design the information I need is usually scattered all over the internet, usually a few words here and there and never enough for what I need, thus there is no substitute for getting information from the horses mouth, I'd be happy to hear any and everything you're willing to share with me on the subject.
  Reply With Quote
Old 15th May 2017, 03:46 AM   #17
diyAudio Member
 
bolserst's Avatar
 
Join Date: Jun 2005
Location: Fort Worth, Texas
Quote:
Originally Posted by urmom View Post
Are there pros/cons to using smaller strips vs a single big one other than efficiency?
Distortion and coloration increases with wider strips because the flux density variation across the gap increases as the magnet separation is increased.

Flux density formulas here: Magnetic Flux Density Formulas from Australian Magnetic Solutions
Online calculator/plotter here: Graphs of Magnetic Flux Density - Online calculator from Australian Magnetic Solutions

Standalone calculator/plotter for flux density between a pair of rectangular magnets created by diyaudio member posted here:
DIY ribbon dipole tweeter, reductio ad minimum
If you read this thread from the beginning you will see the OP was experimenting with a spaced/stacked magnet geometry to reduce the flux density variation in the gap.

Last edited by bolserst; 15th May 2017 at 03:49 AM.
  Reply With Quote
Old 15th May 2017, 10:59 AM   #18
lowmass is offline lowmass  United States
diyAudio Member
 
Join Date: Jan 2016
urmom,

There really is no substitute for simply throwing somthing together out of superglue and popcicle stiks and just start to play. The ribbon is about the easyest transducer to build and will perform suprisingly well as a headphone even in the crudest form.

I made my first ribbon headphone from nothing more than a few magnets, a 2 inch by 3 inch squares of cheap wood panel about 1/8 in thick with a rectangular hole cut in middle. The magnets just superglued on to wood . A simple flat structure. At ends where ribbon attaches were small block of wood glued on. These 1/2 height of magnets so ribbon suspended at middle of magnet depth. The ribbon was tacked onto these blocks with double sided tape and a simple wood screw run through with wire under it to connect to amp.
I ran a 4 ohm resister in series with ribbon and hook it all directly to amp outputs. With ribbon close to ears they were plenty loud enough AND will have suprising bass!

This units ribbon was 3 inches long and 3/4 inch wide. The magnets were about 1/2 inch deep. true free swinging ribbon cut out of kitchen foil. The magnet flux would likley model to show quite a bit of variation across gap BUT after a few experaments my ears told me that this is not nearly as big an issue as expected. Just dont try to widen magnet gap too much. This was close to max.

Just a simple bare bones ribbon you can make from almost nothing that you can play around with while you plan and learn. You will actually save yourself a ton of wasted time by playing around a bit to help guide your design decisions. Attempting to design without hands on real world knowledge almost always ends up making an unessasarily complex device that has issues.

Last edited by lowmass; 15th May 2017 at 11:08 AM.
  Reply With Quote
Old 15th May 2017, 02:23 PM   #19
urmom is offline urmom  United States
diyAudio Member
 
Join Date: Apr 2016
Cool, I will try that experiment and do some reading from that forum bolserst linked.
In your opinion can ribbon headphones sound as good as commercial high end options?
  Reply With Quote
Old 15th May 2017, 05:01 PM   #20
lowmass is offline lowmass  United States
diyAudio Member
 
Join Date: Jan 2016
Ive never heard a commercial "high end" headphone. all I can say is a simple ribbon completely out performed ALL the others I have heard by a large margin.

Get some experience just making simple ribbons. Theres probably nothing more important to good design than actual hands on real world development. Were I work we call CAD "cartoon land" were everything works and everything seems right, until its actually built
  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
New design for segmented ribbon tweeters Spatz Planars & Exotics 8 5th June 2013 09:55 PM
DIY ribbon design/construction thadman Planars & Exotics 6 11th November 2009 09:14 PM
Important areas of ribbon motor design goskers Planars & Exotics 6 2nd June 2008 07:49 PM
bookshelf design around foster ribbon aleexman Planars & Exotics 0 19th December 2007 04:06 PM
Ribbon magnetic design leiade Multi-Way 2 20th September 2002 06:11 AM


New To Site? Need Help?

All times are GMT. The time now is 10:08 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright ©1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2
Wiki