this is my prototype, sounds great, now i have to make nice looking case.
here on my monitor with Aurum Cantus 130MK2
An externally hosted image should be here but it was not working when we last tested it.
here on my monitor with Aurum Cantus 130MK2
An externally hosted image should be here but it was not working when we last tested it.
Very nice! You can't get away with just teasing us with a couple of pictures! How about some details; ribbon width, length, magnet size, crossover frequency, slope? What's nexr?
Denis
Denis
Hello,
Total magnets size is 10x10x200mm, for frame I'm using 14x14mm steel, foil is 12um (baking foil) I dont know where to buy in my country thinner foil. I've build it couple days ago and it's not well measured yet. It plays linear to 1k, but I don't know how dissortion looks below 2k I'have to measure them in a free time. Now my ribbon plays about to 2.5k 1sth order.
I havent finished transformer, it has good freq response
but impedance is not good, it was measured without ribbon:
Transformer, core from ATX supply:
Fabric ribbon tweeters has linear impedance like this:
Maby they are using impedance linearisation with resistor and capacitor, because here is written that DCR is 0.02R
http://www.madisound.com/neocd3.0.html
now I'm going to buy magnets for next ribbon and buy some good cores.
I'm very suprised becouse I don't have thin foil, 0.4T and It's very loud!! I am also going to make steel back to improve magnet force in gap.
With generator the ribbon plays even 200Hz 🙂
big photo:
Total magnets size is 10x10x200mm, for frame I'm using 14x14mm steel, foil is 12um (baking foil) I dont know where to buy in my country thinner foil. I've build it couple days ago and it's not well measured yet. It plays linear to 1k, but I don't know how dissortion looks below 2k I'have to measure them in a free time. Now my ribbon plays about to 2.5k 1sth order.
I havent finished transformer, it has good freq response
An externally hosted image should be here but it was not working when we last tested it.
but impedance is not good, it was measured without ribbon:
An externally hosted image should be here but it was not working when we last tested it.
Transformer, core from ATX supply:
An externally hosted image should be here but it was not working when we last tested it.
Fabric ribbon tweeters has linear impedance like this:
An externally hosted image should be here but it was not working when we last tested it.
Maby they are using impedance linearisation with resistor and capacitor, because here is written that DCR is 0.02R
http://www.madisound.com/neocd3.0.html
now I'm going to buy magnets for next ribbon and buy some good cores.
I'm very suprised becouse I don't have thin foil, 0.4T and It's very loud!! I am also going to make steel back to improve magnet force in gap.
With generator the ribbon plays even 200Hz 🙂
big photo:
An externally hosted image should be here but it was not working when we last tested it.
Transformer Measurement
Hello Uwe,
try to remeasure your little toroid again with some known impedance at the secondary winding, i.e. 0.1 ohm. The transformer is transforming secondary impedance to primary; afais secondary shouldn't be left open. Would be interested to see the results. How many windings do you use for primary and secondary? Good luck!
Hello Uwe,
try to remeasure your little toroid again with some known impedance at the secondary winding, i.e. 0.1 ohm. The transformer is transforming secondary impedance to primary; afais secondary shouldn't be left open. Would be interested to see the results. How many windings do you use for primary and secondary? Good luck!
open secondary:
secondary with ribbon tweeter:
primary:
27 turns 3wires parallel
secondary:
5turns 5wires parallel
wires are from CAT5
I'm going to buy EI core here are some specs with is good? :
http://tme.pl/arts2/pl/a24/e13_7_4-3c90.html
An externally hosted image should be here but it was not working when we last tested it.
secondary with ribbon tweeter:
An externally hosted image should be here but it was not working when we last tested it.
primary:
27 turns 3wires parallel
secondary:
5turns 5wires parallel
wires are from CAT5
I'm going to buy EI core here are some specs with is good? :
http://tme.pl/arts2/pl/a24/e13_7_4-3c90.html
Heavy load
Hello Uwe,
this looks like a very heavy load for your amplifier: afais you just get some 2 ohms at your specified crossover frequency at 2500 Hz. Perhaps you should have at least 50 turns on your primary winding.
Hello Uwe,
this looks like a very heavy load for your amplifier: afais you just get some 2 ohms at your specified crossover frequency at 2500 Hz. Perhaps you should have at least 50 turns on your primary winding.
I'm rebuilding my prototype to improve magnetic force, here are some photos
I think it will be finished tommorow 🙂
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
I think it will be finished tommorow 🙂
Denis, ygem
Your projects look great gents!
Hopefully I can start mine soon,
anyone willing to do Femm modeling for me? 😱
Your projects look great gents!
Hopefully I can start mine soon,
anyone willing to do Femm modeling for me? 😱
I have been makin my own ribbons also and ran into a few problems.The first is my transformer,i can only get the ribbon loud enough on about 2ohms instead of 4-5 ohms.I also cant stop low frequencys getting through to the ribbon.Any ideas anyone?thankyou.
Ahh, I like this - have a similar project, and have build fullrange ribbon long time ago
Now its two ribbons from 1.2khz,......dont think its possible to get any lower without problems
Magnet strays like to follow nice round curved iron yokes...north/south.....
And I would think its important to have ribbon exsactly in the middle
And be carefull not have a too wide a ribbon.... magnets loose a lot of strength
It is a tricky thing to mount ALL magnets with correct orientation
Now its two ribbons from 1.2khz,......dont think its possible to get any lower without problems
Magnet strays like to follow nice round curved iron yokes...north/south.....
And I would think its important to have ribbon exsactly in the middle
And be carefull not have a too wide a ribbon.... magnets loose a lot of strength
It is a tricky thing to mount ALL magnets with correct orientation
Attachments
daz84, do you still have problems or have you solved it
received my neo magnets from TheSuperMagnetMan
Two dicount bundles in perfect condition - 64USD with shipping
20 pieces measureing 40x22x10 mm and magnetized through the width - quite perfect fore mid/tweeter
received my neo magnets from TheSuperMagnetMan
Two dicount bundles in perfect condition - 64USD with shipping
20 pieces measureing 40x22x10 mm and magnetized through the width - quite perfect fore mid/tweeter
Hello Tinitus,
that sounds very promising indeed. Good luck with your project. I'm very interested in your results.
that sounds very promising indeed. Good luck with your project. I'm very interested in your results.
I am glad to see that this thread had started again.
I have finished my project a year ago. It is 1m long, 12kg heavy, divided into 3 sections. It uses very complicated magnetic&metal structure and beacause of that it is so heavy. Magnetic field is 0,3T (+/- 0.01T). The membrane is for test purposes only and since it's pretty heavy (20um mylar and 11um aluminium foil, instead of 2um mylar and 6um alu) so the sensitivity is not that good. This is so called quasi ribbon, without transformer.
Sound is absolutely great, i am driving speaker from 250Hz up (4 order digital crossover). Because of it's lenght, vertical sound dispersion is poor, but we always sit at same level anyway. You can very clearly distingish every hand clap in applause, string instruments sound great, and the sence of depth is just amazing.
And just to tell you, the prices of magnets in china are about 25$/kg, with shipping about 50$/kg, and magnets can be in any shape that you like them to be (at same cost). I got mine for about 100euros for both speakers from other source .
And here is a little picture.
Keep up with great projects!
Mx
I have finished my project a year ago. It is 1m long, 12kg heavy, divided into 3 sections. It uses very complicated magnetic&metal structure and beacause of that it is so heavy. Magnetic field is 0,3T (+/- 0.01T). The membrane is for test purposes only and since it's pretty heavy (20um mylar and 11um aluminium foil, instead of 2um mylar and 6um alu) so the sensitivity is not that good. This is so called quasi ribbon, without transformer.
Sound is absolutely great, i am driving speaker from 250Hz up (4 order digital crossover). Because of it's lenght, vertical sound dispersion is poor, but we always sit at same level anyway. You can very clearly distingish every hand clap in applause, string instruments sound great, and the sence of depth is just amazing.
And just to tell you, the prices of magnets in china are about 25$/kg, with shipping about 50$/kg, and magnets can be in any shape that you like them to be (at same cost). I got mine for about 100euros for both speakers from other source .
And here is a little picture.
Keep up with great projects!
Mx
Attachments
MX, thats a nice one - but down to 250hz, wont that be a problem ?
Cant help but posting this one - I know that bass section is made of sixteen 5" woofers, every each one of them in its own chamber with BR
A friend has heard them, and says its the best he has ever heard, and he has listened to some serious stuff
http://www.positive-feedback.com/Issue18/megaline.htm
Magnets, .. sound interesting if we can order any shape we like
Those low prices, are that neodynium magnets
Cant help but posting this one - I know that bass section is made of sixteen 5" woofers, every each one of them in its own chamber with BR
A friend has heard them, and says its the best he has ever heard, and he has listened to some serious stuff
http://www.positive-feedback.com/Issue18/megaline.htm
Magnets, .. sound interesting if we can order any shape we like
Those low prices, are that neodynium magnets
No it's not a problem, the ribbon is not moving at all. Offcourse it must be at least 4th order crossover. When i make new foil, i will measure it and then i will know exactly where to crossover it.
Yes, magnets are N45, the strongest neodymium ones. You can look at www.alibaba.com for the names of firms and contacts.
Yes, magnets are N45, the strongest neodymium ones. You can look at www.alibaba.com for the names of firms and contacts.
N45 - I didnt know that was related to magnet strenght 
Mine are "only" N35 - but still pretty strong
I would like to measure/exsperiment to find the optimal width of magnet gap and ribbon
But I still havent figured out how to handle the magnets, without hurting my fingers
or damage the magnets 
Mine are "only" N35 - but still pretty strong
I would like to measure/exsperiment to find the optimal width of magnet gap and ribbon
But I still havent figured out how to handle the magnets, without hurting my fingers
or damage the magnets Well, I had to try, result - one magnet damaged and broken in two, damm
But my finding were that 22mm gap is too much - around 15mm gap seems much better
I have some much smaller magnet, and they seem fine with 12mm gap
Have to rethink the project - either buy more of the same magnets or order better ones
A bit dissappointing
At the moment I can make a small ribbon 100x8mm
And a "bigger" one at 180x14mm, no point in making it longer at this width
Guess that will be ok, but really not what I had hoped fore !
But my finding were that 22mm gap is too much - around 15mm gap seems much better
I have some much smaller magnet, and they seem fine with 12mm gap
Have to rethink the project - either buy more of the same magnets or order better ones
A bit dissappointing
At the moment I can make a small ribbon 100x8mm
And a "bigger" one at 180x14mm, no point in making it longer at this width
Guess that will be ok, but really not what I had hoped fore !