Hi all of you.
I have been offered some surplus neodynium magnets and got the idea to use them for making a pair of ribbon drivers. The magnets are WERRY powerfull. This should give a driver with a high sensitivity. Have anny of you heard about others using these magnets for DIY?
About making the ribbon foil with the conductive foil, where can i find information about this?
Thanks for helping out.
Peter Jensen
I have been offered some surplus neodynium magnets and got the idea to use them for making a pair of ribbon drivers. The magnets are WERRY powerfull. This should give a driver with a high sensitivity. Have anny of you heard about others using these magnets for DIY?
About making the ribbon foil with the conductive foil, where can i find information about this?
Thanks for helping out.
Peter Jensen
One of my audio buddies has built mid & tweeter ribbons... he couldn't afford Neo magnets -- if you have enuff of them it should be doable -- because of the pull it can be tricky getting the magnets into position -- watch your fingers.
dave
dave
Actually I'm planning to try my hand at building a long ribbon driver. The ribbon fabrication and magnet placement is fairly easy. But for a short ribbon (like the stage accompany, raven, etc) have short ribbons (for good vertical dispersion) and thus the ribbon is very low impedance and needs a matching transformer.
My idea is to make a much longer ribbon and pick the ribbon thickness and width to get me to a reasonable (4 ohms or so) impedance without a matching transformer. I haven't done the calculations yet, and I'm hoping that I don't need a 30 foot high ribbon.
Sheldon
My idea is to make a much longer ribbon and pick the ribbon thickness and width to get me to a reasonable (4 ohms or so) impedance without a matching transformer. I haven't done the calculations yet, and I'm hoping that I don't need a 30 foot high ribbon.
Sheldon
stokessd said:
My buddies midrange ribbon is 5 or 6' long and he still needs a matching trafo...
dave
Hi again
Thanks for replying.
I know of the impedance problems with ribbons. I was thinking of making a line source combined with a dipol sub. Using these magnets i think it could be made using a quite wide midrange ribbon 4-8 cm combined with a more narrow 1 cm tribble ribbon in the same gap. (X-over 5khz or so) This would not be posible using standard magnets (to low a field when taking the magnets to far apart = low sensitivity), but it might be posible using neodynium ones. The reason why i would like a wide midrange is to improve the low freq respons of the system. X-over to the bass should be about 100 Hz or so. I have made ribbons before (La folia) and i remember thet the hard part was to make a relative wide ribbon that had a good tribble respons. Making a light narrow tribble ribbon with a good tribble respond is not hard.
Problems. Would it be posible to mount a tribble ribbon in front of a midrange ribbon in the samme magnet gap? An other option would be to mount the trible ribbon beside the midrange ribbon. Maybe in a M - T - M configuration with a pair of midrange ribbons beside a tribble ribbon.
About mounting the magnets are surplus mountes on a steel bracket with holes, so they are easy to mount.
What do you think?
Peter
Thanks for replying.
I know of the impedance problems with ribbons. I was thinking of making a line source combined with a dipol sub. Using these magnets i think it could be made using a quite wide midrange ribbon 4-8 cm combined with a more narrow 1 cm tribble ribbon in the same gap. (X-over 5khz or so) This would not be posible using standard magnets (to low a field when taking the magnets to far apart = low sensitivity), but it might be posible using neodynium ones. The reason why i would like a wide midrange is to improve the low freq respons of the system. X-over to the bass should be about 100 Hz or so. I have made ribbons before (La folia) and i remember thet the hard part was to make a relative wide ribbon that had a good tribble respons. Making a light narrow tribble ribbon with a good tribble respond is not hard.
Problems. Would it be posible to mount a tribble ribbon in front of a midrange ribbon in the samme magnet gap? An other option would be to mount the trible ribbon beside the midrange ribbon. Maybe in a M - T - M configuration with a pair of midrange ribbons beside a tribble ribbon.
About mounting the magnets are surplus mountes on a steel bracket with holes, so they are easy to mount.
What do you think?
Peter
That looks like the magnet from a hard drive.
I just read some DIY ribbon stuff on www.snippets.org. John R. Whittaker's "cautionary tale" didn't motivate me. Sounded like a disappointing experience.
When I get home I'm going to check out May2001 of AudioXpress which had a DIY ribbon article by Justus Verhagen.
I just read some DIY ribbon stuff on www.snippets.org. John R. Whittaker's "cautionary tale" didn't motivate me. Sounded like a disappointing experience.
When I get home I'm going to check out May2001 of AudioXpress which had a DIY ribbon article by Justus Verhagen.
It takes a remarkable amount of B and H fill a 3/4" gap at 2Tesla. Not to mention a whole mess of steel...
http://www.soundimage.ishoejby.dk/Different-col/Ribbon.htm
Those ESG ribbons are pretty reasonably priced.
happy experimenting, John
http://www.soundimage.ishoejby.dk/Different-col/Ribbon.htm
Those ESG ribbons are pretty reasonably priced.
happy experimenting, John
Here's some *BIG* Nd magnets I saw recently. A great way to hurt yourself quick if you're not careful. 2 little 1.25"x0.5"x0.15" Nd35s once gave me a blood blister. I would think through every movement before I picked up one of these brutes.
4x5 square N38
4" dia. N38
4x5 square N38
4" dia. N38
Nd
Hi again
These are BIG
, but also werry expensive 🙁 . The surplus ones I have considered cost a small fraction of the price of these 😉 . I am thinking of using a lot of them to make somthing like a 150 Cm line source
. This will take a LOT of magnets so they need to be cheap. Still using cheap surplus Nd magnets will give more power then stardard megnets normally used for making ribbons. I will be making some experiments in the future with these. I will let you know.
Peter Jensen
Hi again
These are BIG
, but also werry expensive 🙁 . The surplus ones I have considered cost a small fraction of the price of these 😉 . I am thinking of using a lot of them to make somthing like a 150 Cm line source . This will take a LOT of magnets so they need to be cheap. Still using cheap surplus Nd magnets will give more power then stardard megnets normally used for making ribbons. I will be making some experiments in the future with these. I will let you know.Peter Jensen
Yeah, I agree those biggies aren't much use for audio apps.
If you haven't already, do a "neodymium" search of Ebay. I saw what seemed to be pretty good prices there on large lots of small Nd mags.
Have fun with your ribbon experiments.
Bill
If you haven't already, do a "neodymium" search of Ebay. I saw what seemed to be pretty good prices there on large lots of small Nd mags.
Have fun with your ribbon experiments.
Bill
Have you considered an electrostatic driver? Easier to build, and less moving mass. I keep getting drawn toward building my own ribbon drivers, but I'm so pleased with my ES panels that it's not a high priority except for my engineering curiosity.
Sheldon
Sheldon
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