What alloys are used to manufacture microphone bodies?
- Thread starter mudevilo
- Start date
Help Support GroupDIY Audio Forum:
Good or half-decent ones, usually brass. Aluminium, less likely/often (although the body tube of some BM800's feels light enough).
Steel's too expensive / hard to machine, and it's heavy.
With aluminum you might run into electrical contact issues (shielding against interference) at the ends of the body tube, where it's supposed to meet the headbasket & chassis. Although the same can be "achieved" with brass, if it ends up getting painted over...
Steel's too expensive / hard to machine, and it's heavy.
With aluminum you might run into electrical contact issues (shielding against interference) at the ends of the body tube, where it's supposed to meet the headbasket & chassis. Although the same can be "achieved" with brass, if it ends up getting painted over...
A lot of cheaper microphone bodies are zinc alloy. It's cheap, hard and not magnetic and it has decent acoustic properties, I don't absolutely hate it. It tends to be that microphones that are cheap enough to use it don't have very much thought put into acoustics.
Brass and zinc alloy require totally different metalwork process.
Brass is turned/milled/drilled, generally from a cylinder. In the end, a lot of material is "wasted" in chips, and the labour cost is high.
Zinc alloy is based on molding, which is less expensive if large quantities are made, then the amount of turning/drilling is much reduced.
Brass is elastic, which means it can resonate more and is not as sturdy as zinc alloy, although the latter can be bristle and break.
Magnetic properties are not desirable for a mic body.
Actually, a mic body does not have to be metallic; there are many examples of wood and plastic-bodied mics, some of them are quite good.
Brass is turned/milled/drilled, generally from a cylinder. In the end, a lot of material is "wasted" in chips, and the labour cost is high.
Zinc alloy is based on molding, which is less expensive if large quantities are made, then the amount of turning/drilling is much reduced.
Brass is elastic, which means it can resonate more and is not as sturdy as zinc alloy, although the latter can be bristle and break.
Magnetic properties are not desirable for a mic body.
Actually, a mic body does not have to be metallic; there are many examples of wood and plastic-bodied mics, some of them are quite good.
Cheap mic bodies are also made of Zamac (Zinc, Magnesium, Copper). It's cheaper because it has a low melting point, so it's easier to melt and pour into a mould. It doesn't rust, but it's not acid-proof. It's not very strong and rather brittle. It doesn't ring much and sounds rather dull, which is good for mic bodies.
It's popular for cheap parts, cause you can also hide metals you want to get rid of by adding them to the alloy. So don't lick that cheap mic
For mics, the only disadvantage is that it's not easy to get a good electrical connection for ground.
It's popular for cheap parts, cause you can also hide metals you want to get rid of by adding them to the alloy. So don't lick that cheap mic
For mics, the only disadvantage is that it's not easy to get a good electrical connection for ground.
pvision
Well-known member
Sounds like the perfect job for a 3D printer. You can get metal filament, a mix of plastic & metal powder, which might be ideal
If you don't mind hiring out the job (or are very wealthy and want to purchase a specialty 3D printer), there are printers which work by shaking down a thin layer of metal dust, then melting the metal dust together with a laser in the locations which should be solid. I think the term to look for is "selective laser sintering." The resulting structure is not quite as strong as a machined part, but you can make relatively complex shapes that would be difficult to machine and it is entirely metal, as opposed to the metal impregnated plastic that you get with fused deposition filament construction.
It sure can be done.
I toyed with the idea for using dynamic capsules that I had.
It is basic PLA filament, so it's not conductive; I had to apply a layer of carbon paint for electrostatic shielding.
@abbey road d enfer :
Nice project !
Nice project !
pvision
Well-known member
These have got very sophisticated now. Papadakis Racing had an exhaust manifold 3D printed in Inconel. That's about as a tough an environment as you'll find for any part
GeorgeToledo
Well-known member
- Joined
- Mar 3, 2015
- Messages
- 380
The thin aluminum that Neumann uses helps the mic body not be especially resonant.
Some manufacturers use brass, which is pretty resonant, and try to fight that by increasing mass of the body. I don’t know how well that really works.
GeorgeToledo
Well-known member
- Joined
- Mar 3, 2015
- Messages
- 380
I’m sure that some manufacturers have done things along those lines. I’m not sure if it was always for resonant quality.
CAD coated some of their condensers in a rubberized coating. It didn’t necessarily age well. I think there are some others that did the rubber coat.
There was a short lived offshoot of SE brand, Karma, which rebranded ShuaiYin microphones. They would wrap their mics in vinyl.
Certain shockmounts can also do a fair to good job damping body resonances, so it is always a good idea to keep that in mind before fully freaking out.
Internal structures can also dampen body resonance a lot so it's important not to judge a body by how it sounds when it's empty. I once saw a body that was intentionally designed to ring like a bell in a certain place and then aggressively dampened in that one place when fully assembled, so the body would send all the energy to one place and then that one place would be designed to eat all the energy. It was quite brilliant.
I can confirm, my sE X1 is not that nice to the touch. I cleaned off that coating from the body/bottom bell years ago, but nowadays the headbasket half is also sticky (including the mesh)...
GeorgeToledo
Well-known member
- Joined
- Mar 3, 2015
- Messages
- 380
Note to mic manufacturers. Do NOT use materials that require the mics to be reconditioned like a vibrator.
Similar threads
