Ribbon headphone

[gentlevoice1]

Hi DIY's,

I'm about to build a ribbon headphone but before deciding on which magnets to use and which magnetic conductive material to use between the magnets I would appreciate inputs from other DIY's who have experience with this.

More specifically, I'm considering using a thin membrane, appr. 2 centimeters wide and 5 centimeters long, placed between magnets. A membrane as thin as possible. The magnets will be connected with a suitable material - to allow for magnetic conduction between them.

This is akin to a ribbon microphone so I wonder if any of you have suggestions for what is considered a very good magnetic conduction material with low hysteresis - which also "sounds" superb (if it adds a tonal imprint).

Also if you have experiences with different magnet types, and other ideas/suggestions?

Inputs are appreciated

Regards,

Jesper

 

[rodabod]

Out of interest, have you looked into what the low frequency preformance might be like? The ribbon will need to be kept within the magnetic flux for larger excursions which I would imagine could potentially be quite large.

I suppose ribbon transformers might be suitable as a starting point to give you an impedance in the range of typical headphones. Level handling for the transformer would be a consideration though. An active design could be interesting.

I'm guessing Neodymium bar magnets are probably the way to go. You used to be able to buy them on Ebay. Not sure where else.

Roddy

 

[gentlevoice1]

Hi,

Thanks for your comments & suggestions.

I normally do not play very loud and observing the excursions on my current headphone (Onkyo DP-600) I would say that they are a fraction of a millimeter when played at its loudest. So I would not consider this an issue. Are you thinking of other aspects that may affect low-frequency response besides the tensioning of the membrane?

I'm looking for a headphone that is utterly transparent, and as far as I have heard elsewhere, transformers may not be that transparent.... I realize the impedance will be quite low (depending on choice of conductive material for the membrane, and design, it probably will be in the range of 3- 15 ohms). I will be making a relatively small battery-driven amplifier to drive it.

Thanks for the suggestion about neodymium. Can I ask you - do you suggest this because of the magnetic field strength or because you have experienced that this material has some positive soundqualities (what would they be)?

I will post my design progress here in this thread, and if any of you have comments or suggestions feel free to "opt in" :grin:

However, I do have a busy schedule so I may not be in this forum more than once or twice a week.

Regards,

Jesper

 

[rodabod]

[quote author="gentlevoice1"]Are you thinking of other aspects that may affect low-frequency response besides the tensioning of the membrane?[/quote]

Not really. I'm guessing you'll need to keep them open back for flat response, although I'm not sure about enclosures for headphones.

I'm looking for a headphone that is utterly transparent, and as far as I have heard elsewhere, transformers may not be that transparent.... I realize the impedance will be quite low (depending on choice of conductive material for the membrane, and design, it probably will be in the range of 3- 15 ohms). I will be making a relatively small battery-driven amplifier to drive it.

Transformers can be very clean. My only concern was the levels involved really. A specific active design could be nice. I'm not sure where you got the figure of 3-15 Ohms from though.... I'm guessing you will find it is lower by maybe a factor of ten.

Thanks for the suggestion about neodymium. Can I ask you - do you suggest this because of the magnetic field strength or because you have experienced that this material has some positive soundqualities (what would they be)?

Strength and therefore size.

Cheers,

Roddy

 

[ts8051]

Out of interest, have you looked into what the low frequency preformance might be like? The ribbon will need to be kept within the magnetic flux for larger excursions which I would imagine could potentially be quite large.

I suppose ribbon transformers might be suitable as a starting point to give you an impedance in the range of typical headphones. Level handling for the transformer would be a consideration though. An active design could be interesting.

I'm guessing Neodymium bar magnets are probably the way to go. You used to be able to buy them on Ebay. Not sure where else.

Roddy

Hello, I made such ribbon headphones with succsess. I used 4 bar neodymium magnets N52 60 X 5 X 3mm from Amazon.de. As a conductive non magnetic membrane (ribbon) i used aluminium foil 20 X 60mm from normal material for food wrapping. I reduced the thickness of the aluminium to be lower than 10 microns with etching in hydrochloric acid (for about 20min). The produced headphone drivers have flat responce in middle frequencies and good bass responce related with the small surface of the vibracing ribbon. My question is if there is somewhere a shop selling very thin aluminium foil suitable for this construction.

 

[flashlamp]

lebow foils in the us , I dont know if diyaudio compoents is still open artuer fisher website , maybe else just try chewing gum or cigerette foils or even some icecream foils. are about 6 micron.

 

[flashlamp]

https://lebowcompany.com/foils-list

 

[flashlamp]

looks like arthur fishers website is still open.

https://www.bumblebeepro.com/

 

[flashlamp]

what brand etching solution did you use, or did you make it with the topical solution. or clorox.

that may be a good way to save money on the foil.

 

[flashlamp]

though lebow foils come in big sheets. should provide you more then enough. they may ship to you or they might not .
guess best you can do is call or email them. I think they just might.