U47-style bodies - who can make one?

[Skylar]

RE: capsule mounts & the EQU47

Option A = Thiersch STS-7
http://www.thiersch-mic.de/en/estm_produkte.html
This option is closest to the original.
You'll need to attach the EQU47 capsule mount insulator to the capsule mount disc using m2 set screws (included).
Insert an M3 screw through the bottom of this assembly into the capsule mount itself.
Step 6 in the following image:

Resulting capsule mount height should be 45mm, identical to that of the U47.
Right now, I have a Thiersch capsule and STS-7 mount coming my way.
When these arrive I will, of course, verify the capsule height.

It looks like Thiersch has some new, cheaper mounts—I will probably buy these and try them out as well.



Option B = Chinese-style mount
burdij is selling these in the BM. Similar options are available through lewilson & Peluso Microphones
The bottom of these mounts have two M2 holes, spaced 8mm apart.
The EQU47 will not work with smaller sized holes or different hole spacing than this.
If you choose to use this mount style, you will not need the capsule mount insulator part.
Instead, you'll attach the capsule mount directly to the capsule mount plate with two M2 screws through the bottom of the plate into the mount base.
Step 5 in the following image:

If you use this option, your capsule mount height may be slightly lower (possibly higher) than the ideal 45mm spec.
Use shim(s) to arrive at 45mm height. OR experiment with different capsule heights!



RE: EQU47 basic dimensions
I do not have the drawings/dimensions in front of me now, but I will put together an image and/or PDF of basic dimensions that are of interest.

Here's what I can tell you from memory:
Outside diameter of tube = 60mm
Outisde diameter of headbasket = 63mm
This is a longbody mic—exact length coming soon.
There is a lot of room inside the tube area, so many circuits could be used.




RE: EQU47 connectors
This mic body is designed for the Binder 691 series 7-pin connectors.
I will be arranging a group-buy for these, so that you can get them with your mic body.

 

[Skylar]

I stupidly filled out the survey twice.....doh!  : but my interest is only for one mic....please deduct one from your total & hopefully this won't skew your results too much.

I removed your duplicate.




Emperor-TK, I removed your duplicate submission and added one to your original...is that okay?

 

[Emperor-TK]

Emperor-TK, I removed your duplicate submission and added one to your original...is that okay?

Yes, thanks Skylar, that was my intent.

 

[Skylar]

Hopefully these will help clarify capsule mounting for the Thiersch STS-7 mount.

[click to enlarge]

 

[Skylar]

The feeler is now closed.

If you didn't get a change to fill out the survey, don't worry—you still have a chance to buy a mic body once the design & protos have been validated.


Here are the results of the survey:

Complete Kits = 97.1% Raw Materials Kits = 2.9%

Matte = 37.4%​ Polished = 59.6%​ No Finish = 0.5%​ Other = 2.5%​

When I have the headbaskets finished, I'll have it split 60% polished/40% matte.
I'll leave a few unfinished.



I would like to give my most sincere thanks to those who participated in this survey;
in doing so, you have helped to make this project possible.

 

[travisk]

Hi Skylar,
Thanks so much for your hard work.
I signed up for 2 as "other" chrome. 
Polished would be fine!!!
thanks again
TravisK

 

[FerrariT]

wait, polished or "chrome plated".
I voted matte, because I didn't want chrome plating.
But if they are just polished thats a whole different tune.
Guess I was confused. lol

 

[Skylar]

travisk, I have updated yours to "polished."


Both options will be electroless nickel plated, which is more environmentally friendly than regular nickel plating (and lot more friendly than chrome).

What makes the difference is the surface preparation before plating.

If you bead-blast the parts beforehand, you get a matte finish.
If you polish the parts, you get a shiny, "chrome" look.

The "Matte" option is bead-blasted then electroless nickel plated.
The "Polished" option is highly polished then electroless nickel plated.

 

[loopermc5]

I think I chose matte also but would prefer polished now i understand better if it's no problem.

Thanks for all this!!!

 

[1954U1]

Skylar,

thanks a lot for the info & drawings about mounting, dimensions, connectors.

You're doing an amazing job!

 

[davidvaldes]

I would like to give my most sincere thanks to those who participated in this survey;
in doing so, you have helped to make this project possible.

It´s me who gives you my most sincere thanks. I´ve done nothing but staying to one side and see how experts (with Skylark standing out from the rest) take this project to the happiest possible end.

Your humility, kindness, commitment to the project and generosity for sharing this with the rest of us is simply stunning.

You are a gentleman, and my hat´s off to you, sir...

 

[luis]

Skylar,

Can you change my finish to polished?


Thank you and sorry for the incovinience,
Luis

 

[Kingston]

Thanks for all the mounting and connector data. Exactly what I wanted to know.

 

[tommypiper]

I mentioned way back early in the thread to bear in mind the vertical width of the top metal band of the headbasket, as it's very narrow in a true U47, but always wider in copies and other similar microphones. 

As we know, this top band intersects across the capsule face in the true U47, and impacts the microphone's sonic character... and is therefore important in the design.

My question; has our design been resolved on this point, and measured to be exactly the same as the original (top band on the headbasket)?

(I've scrolled back, but couldn't find this confirmed... so just want to check.)  Thanks.

 

[Skylar]

I remember your earlier comment.

I have gotten four measurements from various users contributing to this thread for the height of the top ring.
These were all measured from original U47s:

4mm <--probably not accurate
4.42mm
4.45mm
4.5mm

What this tells me is that there were probably variations over the years due to manufacturing tolerances.
What THAT tells me is that this spec may not be as crucial as we think.
How many people have you heard say that every U47 sounds slightly different, yet similar?
It's probably due to slight differences like these over the years.
Take a look at the classic photo of ten originals—it's amazing how many differences there are.


Can you tell a 0.03—0.08mm difference with your eyeballs?
That's between 1/1000th—3/1000ths of an inch!

My conclusion is that these slight differences are due to manufacturing variation.
So, when you look at these numbers, you have to think "what did the original drawings most likely specify?"
Now, we know Germans to be precise, exacting beings.
BUT, I have a hard time believing that even the German designer responsible for drafting the original U47 prints specified 4.42mm for this dimension.
It was most likely a nice, round number...4.5mm, which is what the EQU47's dimension is.

 

[tommypiper]

Thanks, Skylar.  That photo is great.  ;D

 

[Skylar]

Thanks, Skylar.  That photo is great.   ;D

I love the obvious "ugly duckling."

 

[Skylar]

loopermc5 & luis, your submissions have been changed to "Polished."

FerrariT, I've got you down for "Matte"; would you like to change yours also?

 

[tommypiper]

Ugly?!  None of them are ugly. I love the green on#3...  oooohh.  I may try to powder coat one that color...

 

[bernbrue]

Hi Skylar,
absolutely fantastic U47 body. Thanks very much!! How can I login/register on your page? Do need to register at all?
regards
Bernd