we got source for the good quality hand made Mulberry paper and they said they can give us custom cone shape if required. We could even get Pure Leather which is supple and very soft.
I have few questions regarding the field coil that as I would like to know that
how many turns in general a field coil driver will have considering like the feastrex kind of full range.
how many ohms will be the resistance and also the thickness of wire as well.
I am simulating the magnetic circuit in Infolytica Magnet and the results are pretty good and easy to work with software.
Can you please tell me the above general values so that I can have good beginning for the driver design.
Will be using 1010 steel for the plates and tons of copper wherever required to reduce the eddy current effects.
I have few questions regarding the field coil that as I would like to know that
how many turns in general a field coil driver will have considering like the feastrex kind of full range.
how many ohms will be the resistance and also the thickness of wire as well.
I am simulating the magnetic circuit in Infolytica Magnet and the results are pretty good and easy to work with software.
Can you please tell me the above general values so that I can have good beginning for the driver design.
Will be using 1010 steel for the plates and tons of copper wherever required to reduce the eddy current effects.
Hello rhythmsandy
We are a small group that design our own speaker, and share info on how to...
Two of us is useing feild coils, so take a look at this thread. http://www.diyaudio.com/forums/multi-way/212953-project-ryu-diy-field-coil-loudspeaker.html
We are a small group that design our own speaker, and share info on how to...
Two of us is useing feild coils, so take a look at this thread. http://www.diyaudio.com/forums/multi-way/212953-project-ryu-diy-field-coil-loudspeaker.html
yeah Frank I saw that its interesting and very informative.
I think I can start the coil simulation with 1400 turns and 1sqmm wire
I have a question that there is a scope for permendur but I want to use only a the top of the pole piece and top plate as the flux density will be too high.
Soon Ill put the simulations over here and see if things are working from there... the pole piece would be 1010 steel.
The former material is something I need to look at Im considering paper but in general the voice coil manufacturers use nomex or glass fibre as paper is not being used these days need to find the source for it.
any more suggestions please welcome...
I think I can start the coil simulation with 1400 turns and 1sqmm wire
I have a question that there is a scope for permendur but I want to use only a the top of the pole piece and top plate as the flux density will be too high.
Soon Ill put the simulations over here and see if things are working from there... the pole piece would be 1010 steel.
The former material is something I need to look at Im considering paper but in general the voice coil manufacturers use nomex or glass fibre as paper is not being used these days need to find the source for it.
any more suggestions please welcome...
I am planning to use flat leather as surround material which is very soft and supple and im happy if I can get +/- 1mm displacement as we will be hardly using 10 to 15w of power...
Why would you use permendur? dos it have a better saturation curve compared to 1010 steel. I tried to find some info on the permendur but couldn't.
I don't know what kind of paper to use for voice coil former, I use fibre glass due to the strength. It dos not compress when transferring the energy to the cone, in my opinion paper is to soft...
If you like you can make rolls in the leather surrounding, just let the leather soak in water for a while and let it dry in a press former.
I don't know what kind of paper to use for voice coil former, I use fibre glass due to the strength. It dos not compress when transferring the energy to the cone, in my opinion paper is to soft...
If you like you can make rolls in the leather surrounding, just let the leather soak in water for a while and let it dry in a press former.
permendur is a metal which can accomodate 20000Gauss flux density in short forms. Its very expensive and hence I would like to use them in the top plates.
Feastrex uses them in top models. Costs about 40k$ for the drivers.
But advantage of going such higher flux is to get the Qts too low and hence the driver will be like very tight in control. Hence you get the input details according to the input signal without loosing anything. That reflects in the timbre in sound very natural.
As far as leather Im not looking to make it round i want it flat since im not looking for large displacements.
Feastrex uses them in top models. Costs about 40k$ for the drivers.
But advantage of going such higher flux is to get the Qts too low and hence the driver will be like very tight in control. Hence you get the input details according to the input signal without loosing anything. That reflects in the timbre in sound very natural.
As far as leather Im not looking to make it round i want it flat since im not looking for large displacements.
I spoke to a owner of field coil driver " Line Magnetic " he said one thing very unique about the field coils is that you get ultimate microdynamics when you compare to the Permanent magnets. I really want to know what really makes that come out?
In the feastrex drivers I dont even see any shorting rings in it so what is making the microdynamics to roll out of the driver? Is it only the field coil`s control overcoming the eddy currents?
In the feastrex drivers I dont even see any shorting rings in it so what is making the microdynamics to roll out of the driver? Is it only the field coil`s control overcoming the eddy currents?
Without in any way knocking either or the general idea (which I think is great -be very interested to see how it progresses), that's assuming said actually / automatically occurs. If it does, it could be due to any one of a number of factors, since 'microdynamics' doesn't have a specific technical meaning. For example, if by that it's a product of micro-resonance of the cone / substrate then you've got a wide number of possible variables, from cone design (size, profile, material) through the same on the suspension & back through the entire electromagnetic circuit.
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From what I figured out...... It is due to permeability, the magntic resistance. From what I could finde the permanet magnets have a higher magnetic resience than a good Steel.
When calculating on magnetic systems you can convert it to a electric diagram.
For a speaker it translate to two generator (one DC the magnet and one AC voice coil) each with there own output resistor. When a sinal is applaed to the voice coil it has a effect on the total magnetic flux for the system.
Now since the resience is lower for the feid coil the flux is more stable, much like a powersupply with low output impedance.... The output dos not chance as much with load. Dos it make any seens?
When calculating on magnetic systems you can convert it to a electric diagram.
For a speaker it translate to two generator (one DC the magnet and one AC voice coil) each with there own output resistor. When a sinal is applaed to the voice coil it has a effect on the total magnetic flux for the system.
Now since the resience is lower for the feid coil the flux is more stable, much like a powersupply with low output impedance.... The output dos not chance as much with load. Dos it make any seens?
Permendur has saturation flux densitiy of 2.3 - 2.4 T
Look for permendur 49 at the bottom of page:
http://www.goodfellow.com/catalogue...TrbrGQWOEENu&ewd_urlNo=GFCat26&type=01&prop=7
Expensive material. I would look for low carbon steel like from 1002 to 1008. Depends what you can afford and procure.
Low carbon steel 1006 - 2.13 T
Properties of soft magnetic materials
Look for permendur 49 at the bottom of page:
http://www.goodfellow.com/catalogue...TrbrGQWOEENu&ewd_urlNo=GFCat26&type=01&prop=7
Expensive material. I would look for low carbon steel like from 1002 to 1008. Depends what you can afford and procure.
Low carbon steel 1006 - 2.13 T
Properties of soft magnetic materials
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