A rubanoid is a form of leaf spring, especially from a mathematical point of view. Don't get bogged down with the car suspension just because it has multiple leaf springs in an arrangement.
"A leaf spring takes the form of a slender arc-shaped length of spring material of rectangular cross-section. In the most common configuration, the center of the arc provides location for the axle"
However, in our case, on end is fixed.
"A leaf spring can either be attached directly to the frame at both ends or attached directly at one end"
The issue have, "though Jerry will/has helped me with" is that its difficult to simulate none isotropic materials, IE Paper, wood etc. I'm looking forward to receiving some new materials as I will be able to compare CAD simulations with real world results, thus sheading some light as to how and where to add dampening material.
Jerry, the plastic side pole bent due to the magnetic forces exerted on them. Bad design on my part, however the replacements seem to be doing well. (My ironless magnetic motor is currently yielding 1.2T, though I'm still playing the configurations).
Another observations (I'm now just rambling though comments welcome) I've noticed the diaphragm warps where the CV is attached, time is a factor of course and I presume this is dues to the heat the CV generates? Okay I've attached the VC to paper which probably doesn't help!
"A leaf spring takes the form of a slender arc-shaped length of spring material of rectangular cross-section. In the most common configuration, the center of the arc provides location for the axle"
However, in our case, on end is fixed.
"A leaf spring can either be attached directly to the frame at both ends or attached directly at one end"
The issue have, "though Jerry will/has helped me with" is that its difficult to simulate none isotropic materials, IE Paper, wood etc. I'm looking forward to receiving some new materials as I will be able to compare CAD simulations with real world results, thus sheading some light as to how and where to add dampening material.
Jerry, the plastic side pole bent due to the magnetic forces exerted on them. Bad design on my part, however the replacements seem to be doing well. (My ironless magnetic motor is currently yielding 1.2T, though I'm still playing the configurations).
Another observations (I'm now just rambling though comments welcome) I've noticed the diaphragm warps where the CV is attached, time is a factor of course and I presume this is dues to the heat the CV generates? Okay I've attached the VC to paper which probably doesn't help!
the thread became so long people reinvent the wheel
not a big deal of course, first of nice Rubba! is used damping in the rubas mostly top and botton this can me rubber window tape, or felt. what it does it kind of make the top and bot not flap around with a delay compared to the original movement in the middle. lower distortion to, but also slightly lower output. thicker paper will have less of this problem, but loses out on efficiency and top end. never a free lunch i want to eat for free !!! COMEONE
the thread became so long people reinvent the wheel
Ah, your back! You know I'm going to spin this to a different angle
Still pondering about your etching VC technique. Again the trade off is weight to magnetic force.PS, I may have some data for my hallbach design...
Ah, your back! You know I'm going to spin this to a different angle
PS, I may have some data for my hallbach design...
yeah about etch coils, indeed wire have allot of benefits to, mostly being able to pack in allot of them
about teh hallbach, post it
hehe well to me a halback cant get more magnetic force out of the magnets its a smart way of redirecting that force. so the benefit compared to steel. is the losses in steel, you dont ahev to deal with.oh yeah and in some cases not having to use steel to begin with
Hello to most ruba developers.
Now I am writing arrogantly and plainly.
What I have built is only similar to a ruba, but better in either case.
Building the Ruba like a leaf spring and beending wave is unnecessarily complicated and, as I read, many years have passed in this treath and various membrane materials are still being considered. you are no longer open to simple new ideas. too bad, but blame yourself.
Now to my prototype: its tonality already sounds exactly the same as my manger msw. just not at the same speed, but it's easy to improve. The spatial representation is different, but I can only test this with two chassis. The volume or the resilience is higher with the prototype. Crossover frequency is ideal at 420 Hz with left. 4 order. membrane size 28x21 cm.
So after 4 weeks I am already there. I don't have to test materials.
From 3mm distance of the magnets, I go to 2mm, so 1.3 Tesla. The voice coil former becomes smaller and thinner and runs in the lower curtain at 6 ohms.
regards
Shared album - Albert Schweitzer - Google Photos
Now I am writing arrogantly and plainly.
What I have built is only similar to a ruba, but better in either case.
Building the Ruba like a leaf spring and beending wave is unnecessarily complicated and, as I read, many years have passed in this treath and various membrane materials are still being considered. you are no longer open to simple new ideas. too bad, but blame yourself.
Now to my prototype: its tonality already sounds exactly the same as my manger msw. just not at the same speed, but it's easy to improve. The spatial representation is different, but I can only test this with two chassis. The volume or the resilience is higher with the prototype. Crossover frequency is ideal at 420 Hz with left. 4 order. membrane size 28x21 cm.
So after 4 weeks I am already there. I don't have to test materials.
From 3mm distance of the magnets, I go to 2mm, so 1.3 Tesla. The voice coil former becomes smaller and thinner and runs in the lower curtain at 6 ohms.
regards
Shared album - Albert Schweitzer - Google Photos
i dont get it.
i've you have read aaaaaaaaalllll the thread. witch is rather long indeed i think we are open to new ideas. but many has been tried before like damping on the upper and bot i believe i said it a few times that when i got distortion lowered (by adding damping top and bot) its not acting much as bending wave , it is not doing so to begin with the lower you go, it is more of a piston just like a normal speaker. thats why stiffness comes into play as well. here a really old video with stiff membrane. witch mitigate having to damp the upper part and top part but loses out on efficiency because also the middle part is damped YouTubedo you got a FEMM sim of the 1.3 tesla ? since thats rather high for the method you use with 4 steel bars and lots of magnets (i dont know the size of the magnets
)By the way as side note i really found the manger to sound rahter bad, almost all designs esl,planar,amt and even rubbas sounded better, but that might be a taste thing.
You got any measurements ? since that would help allot and might help to understand what you did and a good tool to hold a grip on yourself as well, at least i know i need that reality check every now and then(like always since im aware of placebo waiting on every corner to snatch me
) and i think most people.or be plain
..
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Hallo Wrine
The magnets are 5x20x20mm, the iron 6x20mm results in 1.3 Tesla with a distance of 2mm. I don't know how to upload this.
The manager has a certain advantage that only real bending waves have. He can play piano, saxophone, drums and guitar authentically, like no plunger coil chassis. But it is difficult to use. It is also not perfect when sunned. But this realistic one is fantastic. Just like with göbel speakers.
The word bennding wave and addition is difficult to translate with google translater. Manger msw is a Biegewellenwandler converter in German. Deutsche loudspeaker mbl is a Biegeschwinger. could the Ruba be both of these?
Since I am currently driving a 3-way active system with room correction, I have to set the crossover frequency for my bendinng wave chassis a bit high so that the crossover frequencies are sufficiently far apart.
350 Hz would not be a problem either.
greeting
The magnets are 5x20x20mm, the iron 6x20mm results in 1.3 Tesla with a distance of 2mm. I don't know how to upload this.
The manager has a certain advantage that only real bending waves have. He can play piano, saxophone, drums and guitar authentically, like no plunger coil chassis. But it is difficult to use. It is also not perfect when sunned. But this realistic one is fantastic. Just like with göbel speakers.
The word bennding wave and addition is difficult to translate with google translater. Manger msw is a Biegewellenwandler converter in German. Deutsche loudspeaker mbl is a Biegeschwinger. could the Ruba be both of these?
Since I am currently driving a 3-way active system with room correction, I have to set the crossover frequency for my bendinng wave chassis a bit high so that the crossover frequencies are sufficiently far apart.
350 Hz would not be a problem either.
greeting
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Shared album - Albert Schweitzer - Google Photos
Since I pull the membrane inwards on the side, I can do a damping very efficiently because the membrane does not move, so it does not make any stroke movement
Since I pull the membrane inwards on the side, I can do a damping very efficiently because the membrane does not move, so it does not make any stroke movement
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Half Ruba
Hello
Half circle rubanoid
I'm just trying to write important information.
So far I have striven for the lightest possible engine. This was a mistake.
Motor and diaphragm should have the same weight! That's why I tested the engine with additional weight. The high frequencies became louder and the midrange benefited a little.
In my opinion, half circles of the membrane are better than whole circles.
Why?
Half circles also emit bipolar. Not like normal full range speaker chassis that emit dipolar.
That is why there is no need for a baffle as there are no extinguishments.
I can only imagine the advantages of the whole group in the low tone, i.e. where there is no bending wave.
Half circles are much easier to build.
Lateral damping of the membrane is a must! It should also be wide enough. So with a circle diameter of 8 cm, 4 cm damping material. At 5 cm diameter, 3 cm damping material. Don't let anything else talk you into it. Structure-borne noise must be dampened so that it is not reflected.
I don't understand how that should work with rubber ropes. Even a membrane material that has a dampening effect is not a good solution.
Where the coil changes direction, there should be no magnetic field.
My spider is now made of sylomer yellow, 6mm in diameter, clamped in an aluminum bracket, with a 4.5mm hole. This means that the motor can be re-centered at any time.
Sergius' findings on page 83 are very good. With the triangles that are cut and the small membrane radius.
Shared album - Albert Schweitzer - Google Photos
Hello
Half circle rubanoid
I'm just trying to write important information.
So far I have striven for the lightest possible engine. This was a mistake.
Motor and diaphragm should have the same weight! That's why I tested the engine with additional weight. The high frequencies became louder and the midrange benefited a little.
In my opinion, half circles of the membrane are better than whole circles.
Why?
Half circles also emit bipolar. Not like normal full range speaker chassis that emit dipolar.
That is why there is no need for a baffle as there are no extinguishments.
I can only imagine the advantages of the whole group in the low tone, i.e. where there is no bending wave.
Half circles are much easier to build.
Lateral damping of the membrane is a must! It should also be wide enough. So with a circle diameter of 8 cm, 4 cm damping material. At 5 cm diameter, 3 cm damping material. Don't let anything else talk you into it. Structure-borne noise must be dampened so that it is not reflected.
I don't understand how that should work with rubber ropes. Even a membrane material that has a dampening effect is not a good solution.
Where the coil changes direction, there should be no magnetic field.
My spider is now made of sylomer yellow, 6mm in diameter, clamped in an aluminum bracket, with a 4.5mm hole. This means that the motor can be re-centered at any time.
Sergius' findings on page 83 are very good. With the triangles that are cut and the small membrane radius.
Shared album - Albert Schweitzer - Google Photos
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hi there Bipolar does need a baffle if you want to counter the NULL occuring when front meets back but i agree half circles is the way to go. did that early on. it lightens the load on the coil as well.
could you go in depth about weighting the motor ? i mean the motor is the steel and magnets.. i think they are a 1000 times more heavy then the membrane i hope
you might want to take a look at some videos i made with using foam board as membrane, its heavy but stiffen and damps allot. acting more like a DML and or piston at some frequencies. ... more a BML or whatever its called but indeed a spider especially on the backside of the coil former that does not have the half circles keeping the former straigh is a must. i searched everywhere to get the materials to make straigh spiders.. cant find it
but i agree half circles is the way to go. did that early on. it lightens the load on the coil as well. could you go in depth about weighting the motor ? i mean the motor is the steel and magnets.. i think they are a 1000 times more heavy then the membrane i hope
you might want to take a look at some videos i made with using foam board as membrane, its heavy but stiffen and damps allot. acting more like a DML and or piston at some frequencies. ... more a BML or whatever its called
but indeed a spider especially on the backside of the coil former that does not have the half circles keeping the former straigh is a must. i searched everywhere to get the materials to make straigh spiders.. cant find it
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Hello Wrine
What is a dipole or a bipole should be clear. For example, a dipole creates an overpressure in front of the membrane and a negative pressure behind the membrane. Dipolplus - Alles über offene Schallwände
In the Bipol, two membranes radiate overpressure and underpressure at the same time.
It is a little different with the flexible shaft. A bipole-like radiation is generated with a membrane.
ROWEN - Voll-Bipol
I didn't correctly write the term motor because I thought it was clear what was meant.
Let's see what the translator does with the correct terms.
So the following. The voice coil, voice coil former and centering spider should have the same weight as the membrane.
You see how I made a centering spider, it doesn't have to go the entire length? The yellow parts.
I only attached the brackets for testing, as an additional weight:
I've seen a lot of videos with nxt and the like. unfortunately the sound quality on youtube is always poor
regards
What is a dipole or a bipole should be clear. For example, a dipole creates an overpressure in front of the membrane and a negative pressure behind the membrane. Dipolplus - Alles über offene Schallwände
In the Bipol, two membranes radiate overpressure and underpressure at the same time.
It is a little different with the flexible shaft. A bipole-like radiation is generated with a membrane.
ROWEN - Voll-Bipol
I didn't correctly write the term motor because I thought it was clear what was meant.
Let's see what the translator does with the correct terms.
So the following. The voice coil, voice coil former and centering spider should have the same weight as the membrane.
You see how I made a centering spider, it doesn't have to go the entire length? The yellow parts.
I only attached the brackets for testing, as an additional weight:
I've seen a lot of videos with nxt and the like. unfortunately the sound quality on youtube is always poor
regards
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I have been reading through this thread with interest.
I am not the type of person who could consider themselves able to understand the EE theories being discussed, but I am a person who could comfortably build the main parts for a version of this Driver.
The Video coverage of these producing music, offers a impression that this design can deliver a very desirable SQ.
As I am close to commencing a Passive OB Build with a Beyma TPL150 H,
I was beginning to think I could introduce one of these DIY Ribbons at a later date,
to experience their Performance as a comparison to the Beyma.
In the First Post it states that this Driver Design has a 102db efficiency.
Is this a common efficiency being maintained on the differing versions being produced within this thread ?
I am not the type of person who could consider themselves able to understand the EE theories being discussed, but I am a person who could comfortably build the main parts for a version of this Driver.
The Video coverage of these producing music, offers a impression that this design can deliver a very desirable SQ.
As I am close to commencing a Passive OB Build with a Beyma TPL150 H,
I was beginning to think I could introduce one of these DIY Ribbons at a later date,
to experience their Performance as a comparison to the Beyma.
In the First Post it states that this Driver Design has a 102db efficiency.
Is this a common efficiency being maintained on the differing versions being produced within this thread ?
If I were to begin with the process of producing a Support Frame.
Which is the a suitable Height x Width x Depth ?
I have seen a variety of Heights now being produced through the supplied images, am I correct in the assumption the larger the assembly, the lower the Frequency can be rolled off ?
My OB Mid Driver is a Beyma 12P80ND
Which is the a suitable Height x Width x Depth ?
I have seen a variety of Heights now being produced through the supplied images, am I correct in the assumption the larger the assembly, the lower the Frequency can be rolled off ?
My OB Mid Driver is a Beyma 12P80ND
Hello bernt
In your picture I see magnets on both sides of the membrane.
This would be a drive, as with "ordinary" chassis.
You only have to use the magnets on one side and fix the other side so that it cannot move.
The dimensions of the membrane vary depending on the application. page 84 there is good information
regards
In your picture I see magnets on both sides of the membrane.
This would be a drive, as with "ordinary" chassis.
You only have to use the magnets on one side and fix the other side so that it cannot move.
The dimensions of the membrane vary depending on the application. page 84 there is good information
regards