I need a microphone

[Recording Engineer]

Agreed, the Chinese are still far from achieving even a decent CK12.

By the way, Jim's mod of the C414 B/ULS uses the stock capsule. It's amazing to anyone I've ever heard of use one. It makes me wonder if the non-brass CK12s get their bad-rap from an application standpoint even though they are designed specifically for C414s!

In fact, I have to admit my favorite stock C414 are the newest ones since the brass EBs and I think I've convinced myself it's these newest capsules!

But you're absolutely right, you do need to have some intimate knowledge of what's going on (even if it's exclusively from extensive trial and error) to achieve a good mic, but that's regardless of what it costs you in parts!

 

[Bo Deadly]

Well I just bought a used MXL 440 for $65 USD shipped.

I assume this is the usual Schoeps circuit.

What should I do with this?

Traditional U87 pcb kit + transformer?

 

[Tubetec]

Hi Fred,
Your making quite a few assumptions here,
First, its not a 1 gig resistor
Second, even though it may look from that angle that the resistor touches the metalwork ,it doesnt.
Third, the sowter 8230 matches 25kohm into 200 ohm, at a very minimum the mic will feed an input of 1200 ohms ,and on higher level sources I usually terminate with 10 kohms into a line stage with variable gain.
Fourth, Im well aware that the high impedence nature of the grid wiring and associated components is crucial to a good design,thats why I mounted the Ef86 pins up and as close to the capsule as I possibly could .
Fifth, of course 'good' is a totally subjective term but I have 20 or more years experience in sound and recording , over that time Ive used all kinds of condenser mics .When I designed and made this mic I wasnt trying to clone or copy the sound of any mic in particular,Im  willing to accept that the capsule geometry and case dimensions of the B-2 will impart its own signature on the final result.
Sixth, maybe if you were  willing to post details of your own efforts in mic design along with your criticisms of other peoples work you might come across as slightly less judgmental.

 

[Tubetec]

Hi Square,
I'm kinda fond of tube mics personally ,so I couldnt really give much advice on the fet stuff.Great news  that your getting stuck into a project though.
Technicalities aside, one of the really nice things about diy/modding is the sense of satisfaction it gives,and Ive found it to draw in the interest of the musicians and people you might be recording .None of these things are measurable with scopes and probes ,but they do have an effect on the vibe and feel of the end result.

 

[Gus]

Well I just bought a used MXL 440 for $65 USD shipped.

I assume this is the usual Schoeps circuit.

What should I do with this?

Traditional U87 pcb kit + transformer?

http://cdn.recordinghacks.com/images//mic_extras/mxl/mxl-440-circuit.jpg

There is a web site that has good information about upgrading the circuit that microphone looks to have.
I use the stock PCBs and install 1 new part(cut a trace and add some wire) and remove 4 stock parts from the circuit and rewire some connections
I also select new transistors for the JFET and PNPs
Then adjust for min distortion
you can then change caps values and types to taste
Then adjust the DC to DC section
All of this is on the web you just need to look.
I am not a fan of capsule if it is the same as the MCA one(I have a MCA)

There is different China built (not sure where the circuit was designed)transformerless circuit that sounds good stock.
I bought some microphones for the bodies last year (easier than building bodies)and one surprised me. I need to get around to changing the capsule and improving the capsule grill environment. The stock capsule sounds like it was improved over older models.

 

[RuudNL]

Hi Fred,
Your making quite a few assumptions here,
First, its not a 1 gig resistor
Second, even though it may look from that angle that the resistor touches the metalwork ,it doesnt.
Third, the sowter 8230 matches 25kohm into 200 ohm, at a very minimum the mic will feed an input of 1200 ohms ,and on higher level sources I usually terminate with 10 kohms into a line stage with variable gain.
Fourth, Im well aware that the high impedence nature of the grid wiring and associated components is crucial to a good design,thats why I mounted the Ef86 pins up and as close to the capsule as I possibly could .
Fifth, of course 'good' is a totally subjective term but I have 20 or more years experience in sound and recording , over that time Ive used all kinds of condenser mics .When I designed and made this mic I wasnt trying to clone or copy the sound of any mic in particular,Im  willing to accept that the capsule geometry and case dimensions of the B-2 will impart its own signature on the final result.
Sixth, maybe if you were  willing to post details of your own efforts in mic design along with your criticisms of other peoples work you might come across as slightly less judgmental.

+1

 

[Khron]

Hi Fred,
Your making quite a few assumptions here,
First, its not a 1 gig resistor
Second, even though it may look from that angle that the resistor touches the metalwork ,it doesnt.
Third, the sowter 8230 matches 25kohm into 200 ohm, at a very minimum the mic will feed an input of 1200 ohms ,and on higher level sources I usually terminate with 10 kohms into a line stage with variable gain.
Fourth, Im well aware that the high impedence nature of the grid wiring and associated components is crucial to a good design,thats why I mounted the Ef86 pins up and as close to the capsule as I possibly could .
Fifth, of course 'good' is a totally subjective term but I have 20 or more years experience in sound and recording , over that time Ive used all kinds of condenser mics .When I designed and made this mic I wasnt trying to clone or copy the sound of any mic in particular,Im  willing to accept that the capsule geometry and case dimensions of the B-2 will impart its own signature on the final result.
Sixth, maybe if you were  willing to post details of your own efforts in mic design along with your criticisms of other peoples work you might come across as slightly less judgmental.

+1

+1

 

[Tubetec]

Saluts Ruud and Khron !  cheers guys
What I might do is upload a tune I recorded with the modded B-2 and see what people think.
Is it possible within the group diy site to upload music ?
Alternatively I can use file hosting and post a link .

 

[granger.frederic]

Dear Tubetec, Ruud and Krohn,

thanks for the attacks...

as you are demanding, here's an example of a U47 clone that i'm building right now, for a very famous French Producer with a K49 Neumann, Flea Body.

look at the Hiz section , it's built on custom milled plexyglass , point to point and on silent blocks, the tube as well...
the hiZ section is encapsulated between the top plexyglass plate and the tube/foam, like in the original U47.

that's what i do...
but you are free to do your own way of course...

Tubetec , could you post a picture of the red resistor please ? to see the value ...
7:1 min for an EF86 would be better for me but ,once again , you are the only judge...

 

[granger.frederic]

here's some pictures of some of personal mics
of course , i've restored it (near museum shape for certain...) and i use it for comparative listening...

 

[granger.frederic]

again

 

[granger.frederic]

and again

 

[granger.frederic]

i hate self promotion thus i'm stopping and it's not very interesting for the other forum members...
regards
Fred

 

[Khron]

So then why'd you do it?

i hate self promotion thus i'm stopping and it's not very interesting for the other forum members...
regards
Fred

What you choose to name "attacks" were just a polite(?) attempt at sort of "getting you off your high horse", or "knocking you down a peg", in case you're familiar with the phrases

You have to admit, you came across a bit... perhaps arrogant, some might say, with that whole "it's gotta be expensive to be good" attitude. Noone likes a "snobbish" know-it-all, especially in DIY circumstances, i think And bragging about owning(?) expensive mics, indeed, serves no (constructive) purpose. But i could be wrong...

Just to make it 100% clear - no offense or insults were intended, i come in peace.

 

[granger.frederic]

i do it because you asked me ...
now you're upset
sorry, it was not my intentions
i just want to share my knowledge and push builders to think about details (expensive or not, no matter), but i think i won't do it anymore
these days people seem too susceptible...fortunately i'm not, even after your insults

ps:i have also cheap but good mics:

 

[KrIVIUM2323]

Hi,
Frederic don t be touchy about comments, this is probably a problem of translation about tone of your initial comments. And everyone his own choice! This is why diy is interesting!

Anyway, your rubbermount of tube/hi z plate is interesting. What did you use for the rubber?
I always ask for myself why the use of acrylic as there is better insulation material available?

 

[granger.frederic]

Hi
the rubber cames from an old tube socket damping system
but i often use sorbothane rings

plexyglass when perfertly cleaned seems to isolate enough for me and most important ,it doesn't transmit well vibrations,  it's easy to mill and easy to check if it's clean


regards

 

[ln76d]

I always ask for myself why the use of acrylic as there is better insulation material available?

PTFE

 

[KrIVIUM2323]

Yes.
But this have some drawbacks: at same thickness it is softer not as stiff than other material, it is sometime difficult to have consistency when you cut it ( not stable with higher temp), can be dangerous/lethal if you produce temp high enough for it to produce smoke...

Obviously if you have access to water jet cutting(which i don't)... most drawbacks are irrelevants.

 

[Murdock]

Here is a great little table I found online. It states the most important characteristics of the most common plastics.
It's in german but I think you can understand everything with the use of google translator and by looking at the unit table.
7) and 8) are the electrical characteristics:

https://www.hug-technik.com/inhalt/ta/kunstoff.htm#PTFE

Wish I had found this before I build my U67 Pleximount...