Mic body influence on the sound?

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I have posted some measurements of effects of body on the sound, but i cant seem to find which thread it was. Are you interested in what the effect is or what are the principles and why/how this happens.
 
I have seen some people masking fantastic looking mic bodies at a big price, then you have the chinese ones that sell for a fraction of that price. I am sourcing a U47 build, and I wonder if the actual sound of the mic is price relevant?
 
No, the price of the body and where it's manufactured has no impact, it's just regular acoustics that apply, and how the mic is assembled. Some are engineered better than others, off course a Shure ksm44 is way better constructed and engineered than a bm800. But it doesn't mean a bm800 body can't be modified to perform better.

If you go for 1:1 replica of certain mic, yes you need to pay attention to tiniest details, and every dimension, but i haven't noticed the expensive bodies nail the originals either.

Even Premier 800 which looks as 1:1 c800 replica has some serious issues.

I remember commenting that bodies like elam251 should be easiest to clone, at least in theory, because the original body is designed to have minimal resonances, and capsule surroundings should not impact the sound of the capsule a lot. Compared to a u47 which is another story.

The body will impact the sound way more than any exotic component like tube, coupling caps. Body can sometimes ruin the response of perfectly fine capsules. But spending big bucks on a fancy body won't necessarily give you better results.

Also, pay attention, a lot of those more expensive bodies are the same exact asian bodies you can find on Aliexpress.
 
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This stuff is great for deadening too-thin / too-ringing mic bodies:

https://www.amazon.com/Coax-Seal-Moisture-Proof-Sealing/dp/B00075J4J6
Even heavier and denser is Scotch 2229 Mastic tape - like a thicker, stiffer version of the Coax-Seal. Available in pads or rolls.

I'm interested in how this compares to 3M 2228. 2229 is 5mil shy of twice the thickness of 2228 (125 vs 65mils), so a fairer comparison would be 2 layers of the 2228 to one of the 2229.

The 2228 makes for a tight fit with zip ties holding down a Cinemag 13101 in a GT2B body, So the 2229 may be too thick for some applications.

I wonder how different 2228 and 9 are in formula beyond the thickness.

I'll eventually do some tests with the above and sorbothane, which is far and away the most expensive option. I doubt the cost will justify the gains with sorbothane, but I should stay agnostic till I have any useful data to share.
 
I'm interested in how this compares to 3M 2228. 2229 is 5mil shy of twice the thickness of 2228 (125 vs 65mils), so a fairer comparison would be 2 layers of the 2228 to one of the 2229.

The 2228 makes for a tight fit with zip ties holding down a Cinemag 13101 in a GT2B body, So the 2229 may be too thick for some applications.

I wonder how different 2228 and 9 are in formula beyond the thickness.

I'll eventually do some tests with the above and sorbothane, which is far and away the most expensive option. I doubt the cost will justify the gains with sorbothane, but I should stay agnostic till I have any useful data to share.
The stuff is quite malleable - you can streatch/squeeze it down to what ever thickness needed. The Duct Seal is even more workable. It has less bounce-back to it's original shape than the 2229.
 
Aren't body and mesh very important for sound of the mic? I've seen graphs for C12, mesh influences capsule sound, body too.
 
Sure, the whole reason Neumann went to the slanted-front grille on the M49 (then U67/87) is to reduce standing wave reflections between the capsule and the grille, which happens with cylindrical grilles like the U47.
 
M49 is great! Do you find tapes mentioned here doing more or less the same thing as bodies made of correct materials?
I had mechanical problems with lesser bodies for U47, it only made sense replacing them in order to use ele material to full potential. This things are so much easier now although knowing what is good takes a lot of searching.
 
Thanks for that link K Brown. Do you know if that mic will fit a u47fet board? (poctop's is the only one I know of)
 
No, the price of the body and where it's manufactured has no impact, it's just regular acoustics that apply, and how the mic is assembled. Some are engineered better than others, off course a Shure ksm44 is way better constructed and engineered than a bm800. But it doesn't mean a bm800 body can't be modified to perform better.

If you go for 1:1 replica of certain mic, yes you need to pay attention to tiniest details, and every dimension, but i haven't noticed the expensive bodies nail the originals either.

Even Premier 800 which looks as 1:1 c800 replica has some serious issues.

I remember commenting that bodies like elam251 should be easiest to clone, at least in theory, because the original body is designed to have minimal resonances, and capsule surroundings should not impact the sound of the capsule a lot. Compared to a u47 which is another story.

The body will impact the sound way more than any exotic component like tube, coupling caps. Body can sometimes ruin the response of perfectly fine capsules. But spending big bucks on a fancy body won't necessarily give you better results.

Also, pay attention, a lot of those more expensive bodies are the same exact asian bodies you can find on Aliexpress.
I agree that the bodies are more important than most think. In cheaper bodies you can often hear a tone when you tap on them. Do you have any experience with Flea bodies? They are really expensive but I find them to be perfect (and you won't find them on Ali Express :)).

Over ten years ago I made my first U47 clones with the really stylish Thiele M4 bodies (East German microphone). The head is closed on both top and sides so the resonances are unacceptable. It got better (in cardioid) when I moved the capsule from the center to just beneath the grille. Then I switched the unique looking head for a U47 style head from AMI and it got much better bit still it is to resonant to qualify as a high end microphone. The dimensions are close to U47 but the metal is to light and you hear tones when you tap it. Nowadays I do experimental builds in them and I will see what happens when I dampen with some Scotch tape.
 
I’ve just gotten two FLEA C12 body kits and, while expensive, the quality is the best I’ve ever seen in an aftermarket mic body; correct to historic C12 in every detail and dimension I can detect.

If there’s something incorrect with them, it’s too subtle for me to notice. Very impressive
 
I agree that the bodies are more important than most think. In cheaper bodies you can often hear a tone when you tap on them. Do you have any experience with Flea bodies? They are really expensive but I find them to be perfect (and you won't find them on Ali Express :)).

Over ten years ago I made my first U47 clones with the really stylish Thiele M4 bodies (East German microphone). The head is closed on both top and sides so the resonances are unacceptable. It got better (in cardioid) when I moved the capsule from the center to just beneath the grille. Then I switched the unique looking head for a U47 style head from AMI and it got much better bit still it is to resonant to qualify as a high end microphone. The dimensions are close to U47 but the metal is to light and you hear tones when you tap it. Nowadays I do experimental builds in them and I will see what happens when I dampen with some Scotch tape.
Of course replicas that go to that extent of precision are probably worth whatever manufacturer asks/customer is ready to pay. I am mostly talking about those that are in between. I won't name anyone here, but some just rebrand OEM bodies, or make something off the top of their head that vaguely resembles originals, and charge arm and leg for those.
 
In the case of the Coles 4038, the grille shape is an inherent part of the microphone's sound.
 

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Sorry if I revived a zombie thread, but what are some other ways you guys have tried to dampen/deaden the resonance of a mic body (take BM800 as example) besides taping the inside of the body?
 
body is so thin, adding compliant mass will reduce and bring down in frequency resonance.
the grill material is also more rigid ferrous wire; brass wire mesh will likely ring less
 

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