Suggestions for aluminium ribbon damping?

[audioquestM-40]

Originally Posted by dacen

I am in the process of finishing a DIY Apogee (Duetta Signature) like speaker. Right now I am making a corrugator tool for the bass ribbon.

What are you using for the corrugating roller?

[dacen]

Well this is what I have in mind. I am going to modify this machine you see on the picture to handle much wider rollers. I am throwing away these rollers and they are subtituted with the threaded steel rod (x2) that you see on the picture. On these two rods (16mm) my intension is to use Epoxy glue and to fasten a lot of these carbonfiber rods that you see on the picture. They are 2mm by 600mm. I have bought 40 of them and they sell them in every model airplane shop. They have the right stiffness and they have a very even surface and they are completely circular in shape. I believe that these material should be easily available to most people that have an interest.

[audioquestM-40]

[QUOTE=dacen;3217874]Well this is what I have in mind. I am going to modify this machine you see on the picture to handle much wider rollers. I am throwing away these rollers and they are subtituted with the threaded steel rod (x2) that you see on the picture. /QUOTE]

The reason I asked is one day I want to make new bass panels for my Scintillas. The mid's and tweeters I've already made a roller for, and they turned out excellent.
I had a similar idea, but joining rods will leave imperfections. Also the rod would have to be used along the length of the panel and would never turn out 100% straight to make a good roller. What a person needs is an extruded ribbed tube of at least and inch in diameter as it will be strong and consistent. I used to work for a firetruck manufacturing company, and the aluminum handrail tubing is exactly what would be perfect, so that is what I am going to soon purchase and then make a roller system.
I'm not sure when I'll do that as my bass panels are still in pretty good condition, but I do want to do this at some point and will post results.

[dacen]

This looks like something similar : The Scintillating Apogee - Hi-Fi News September 1985

[audioquestM-40]

Originally Posted by dacen

This looks like something similar : The Scintillating Apogee - Hi-Fi News September 1985

Exactly, that is what I want to achieve. If you want to see what a nude Scintilla looks like, here are some shots of mine apart http://s171.photobucket.com/albums/u...e%20Scintilla/

[dacen]

Here is a handwritten procedure for tuning of Apogee Diva. If there is someone interested, here it is:
https://picasaweb.google.com/tsundsd...18306051868834
Don´t remember where I got this from, but it was probably the old Audioworld Straightwire Apogee forum.

[hanski]

Thanks guys for the replies,
could you AudioquestM-40 measure the thickness of the corrugated midrange or tweeter foil?
I could compare it then with my corrugation.

If I ask very kindly, could you also show a picture of your corrugation roller?

[audioquestM-40]

Photo of my roller. The pattern is a little different, but I'm going to give this one a try sometime as comparison to the original which has more pleats

http://i171.photobucket.com/albums/u...MRTWroller.jpg

[Few]

I'm very impressed by the ingenuity posters have shown when devising ways to corrugate, or otherwise pattern, their ribbons. My admittedly limited research on the subject has uncovered more evidence suggesting the corrugation does not help than evidence that it does. I certainly don't want to devalue the contributions of those who have developed nice ways to pattern their ribbons, but is there compelling evidence that it's worth the effort?

I will, of course, shamelessly copy the approaches of those who have come up with nice ways to corrugate the drivers if it is shown to help, but at the moment I remain distracted by the evidence which suggests it doesn't buy you much. Have I just missed the set of data making it clear we all ought to ruffle our ribbons?

Eager to be shown ignorant...

Few

[hanski]

Well, one can make a "ribbon" + frame in so many different ways (traditional ribbon, planar magnetic, or something in between).
My current feeling is that there is no ultimate truth in corrugation. The required SPL and frequency range, ribbon size, material, and the used backing material makes the situation so that there are too many variables to have any consensus.

Btw, the ribbon book arrived and the first thing I learned was that all capacitor foils are NOT usable! Some foils are tin/lead foils. One can try to melt the foil with soldering iron to see if it's aluminium.

Guess which one I'm using in my ribbon headphones?