BG Neo and Magnepan Diaphragm material

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#21
lowmass said:
WrineX, I hear ya about "play". Discovery is best part of this 😉

Yes getting anything below about 12 micron in common laminate will likley be impossible unless U find a roll coater that just happens to have some left over from a custom run.

Y so much adhesive? Well theirs much to say there. I look at laminated ribbon/ plainer same as trying to damp any thin rigid material. For example take car body panel damping methods or speaker box panel damping. A layer of material is applied that has hysteric property. This tends to lower the main resonance a bit BUT more importantly it changes the mechanical property of the panel in a way that can suppress higher frequency resonances. This is where its most effective.

The issue with this method is to get a good "impedance match" without adding so much mass that you have killed sensitivity and or dyed up the sound. The " impedance match" is basically matching the mass of the adhesive/ backing combo to the foil mass to get a good energy transfer from the foil to the adhesive/backing. Think of it like this... try hitting a baseball with a light weight wiffle ball bat. Then hit that same ball with a real baseball bat. Much better energy transfer as the mass of the two is better matched.

So a certain amount of adhesive and backing mass can be a good thing, BUT its far from exact science and must be finessed to find the sweet spot. In the end trial and error hard work and hrs of listening is necessary to nail down a good combination.

What I shoot for is to get as much of that lively and exciting quality that FO (foil only) ribbons have without the metalic edgy signature.

TNT,

ive spent the last 20 yrs attempting to develop a small true ribbon that can operate down to 500 hz. We have seen small tweeter ribbons for years BUT they are typically limited to going no lower than about 1.5Khz and for the majority of the larger woofers out there you really need to cross over at about 500 hz to get that midrange magic we are looking for. The problem is there are very strong standing wave activity in typical ribbon structures below 1.5K and it simply cannot be damped well with standard ribbon designs. To get around this problem ribbon makers just typically make large long ribbons.
A few years back I made a discovery that allows a 6 inch long ribbon to operate reliably down to 500 hz with only a 2nd order xover filter. I applied for a patent, and started my own company. For this reason I dont post too many pics😉. However I have a soft spot for the DIY community so I give info like above from time to time.


The plan uis like the BGs are an answer to getting a low crossover point in a smallish package BUT IMO there is still two issues. 1-their wide so horizontal dispersion is a problem requiring a separate tweeter. 2- IMO as good as the planer is I think the ribbon is still a bit higher class sonic once the lower freq resonances are controlled..
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WrineX, I hear ya about "play". Discovery is best part of this
Yeah i dont take myself to serious, for me it is playing indeed 🙂 i spend allot on my hobby and i like doing it, and learning all kinds of different stuff 🙂

Hmm about the neos's , i create my speaker more like you do an esl segmentation. thats what magnepan does to, and works like a charm if you ask me.

Another story could be bass/mid magneplanar high/mid esl something i built few years back, best of both worlds. ah well many many options. for now i will concentrate on making a simple line array that is small in width for dispersion and tall to get the desired spl. and for very low costs. sort of like the tweeter from a magnepan Tymphani 1D people loved that tweeter, and i tried getting 2 replaced for a customer once and they asked 900 euro for one tweeter........ i said are you completely out of your mind?? there is 40 euro of parts in that thing.

i would make the tweeter taller because the 1D had only half of the 3rd panel filled with the tweeter. since they did not need the extra spl to match the woofers i guess, wished they did make it bigger since there are some examples of people frying them up 🙂 if they made them bigger power handling could go up.

If someone is interested in group buying some of these magnets ill be happy to. of course everyone is raging about neo's but depending on what you want to make, and at what price point getting weaker magnets could fit the bill. for intance if efficiency is no big deal (and size) or if you do want to get low. neos's are out of the picture. unless you spend allot !

About your ribbons , if it is a true ribbon there should not be a backing ? i know a planar is not a ribbon but i believe a true ribbon should be aluminum foil or any other kind of foil unsupported on the left and right side(or at least 2 sides). the ribbons with an laminate are not true ribbons, at least noone classify them as such. so im not sure when you damp a piece of foil if it is still an true ribbon or one of the other category. not that i care about terms but im just curious how they are build up. dont have to give details of course if your patent is still pending
 
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#23
Very nice WrineX. That planer looks quite good. The planer certainly has its strong points. Years ago I actually gave up on the ribbon and concentrated on planers. Then like I said a discovery was made and I refocused on the ribbon.

I too try not to take myself too seriously. Much smarter men have been at this for along time. The discovery I made was not so much from intellect but rather years of hard work eventually "stumbled" on some design details that lead to new structural "form" that is effective at suppressing unwanted ribbon movement.

The patent is pending so not wise to give out too much detail yet. In fact for now even on the web site I kept the details of the technology limited to just a pic. It does show somthing a little different going on BUT doesnt show the inner workings or the ribbons structure. I would love to describe it further but will wait till/ if patent granted. Not sure if I will get in trouble for this but the design can be seen at dynaplaneudio.com

Yea the "tru ribbon" thing. IMO a tru ribbon is basically any free swinging ribbon design clamped only at the ends. Sure we can argue that in its "purest" form its only foil but I look at it from a structural standpoint and from there pur foil or laminated they behave very similar if clamped at the ends only. Such a structure builds resonances differently than a diaphragm clamped on all edges.
 
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#24
TNT said:
like this?

//
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TNT, what is it you would like to re-invent? The principles behind this type of drivers are known. There are a large numbers patents you can read. It is difficult to make copies of the types that uses etched foil on plastic film. There are some limitations when it comes to ribbon or planar drivers that cannot be solved. Well, we can discuss in Swedish off-line too if you prefer…
 
#25
RogerGustavsson said:
TNT, what is it you would like to re-invent? The principles behind this type of drivers are known. There are a large numbers patents you can read. It is difficult to make copies of the types that uses etched foil on plastic film. There are some limitations when it comes to ribbon or planar drivers that cannot be solved. Well, we can discuss in Swedish off-line too if you prefer…
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I'm no inventing, only trying to understand. I'm drawing to inform if I have the right understanding 🙂
 
#39
smaller 6.3 x 2.15 on the bass and 3.8 x 2.8 on treble

well why no neo or ceramic ? , the reason is this i believe, to go low you need surface area. having large surface area and cheap is going rubber magnet. also it is way more easy to build then using ceramic or neo's. it is lighter with shipping. and using weak magnets and loads of surface area you can keep Xmax low without losing out on the spl. and the metal does not haveto be thick to keep it out of saturation since the magnetic force is not that high.

and did i say cheap already 🙂
 
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#40
rhythmsandy said:
i read somewhere that they use 12.5mm x 3mm strips
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No, that is not correct. Size differs overthe years and the various drivers. Bass mostly have 6.35 mm wide magnets strips, thichness is fron 1.59 and up. Tweeters use to be 3.18 mm wide, thickness from 2.54 and up.

WrineX said:
smaller 6.3 x 2.15 on the bass and 3.8 x 2.8 on treble

well why no neo or ceramic ? , the reason is this i believe, to go low you need surface area. having large surface area and cheap is going rubber magnet. also it is way more easy to build then using ceramic or neo's. it is lighter with shipping. and using weak magnets and loads of surface area you can keep Xmax low without losing out on the spl. and the metal does not haveto be thick to keep it out of saturation since the magnetic force is not that high.

and did i say cheap already 🙂
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That is about it! They want to make a nice profit. Better sell many cheap ones that a few expensive ones.
 
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