boogietube
Active member
- Joined
- Jan 17, 2009
- Messages
- 34
Hello all! Here's what I posted and the responses from Klaus's forum:
Well, here we go....I am new to the forum and have read a ton of material here. I feel very outclassed here being a lowly computer electronics tech whose knowledge is out of date. I have built and modified a ton of effects pedals and even one piece of studio gear. The studio that I'm involved in has purchased a mic bottle, a NOS K47 capsule re-diaphragmed by Neumann, a NOS EF42 tube, and a Hauffe transformer. Also, a PSU spec'd for 105 volt output.
I was wondering if anyone had a schematic that would give me a starting point in order to build this thing? Maybe even a pcb layout, or point me to someone who could sell me pcb's for this project?
From what I understand, the EF42 is a pin for pin replacement for the EF12. I would like to post photos and have a lot of input from the forum about completing this project.
Questions and comments are welcome, as I feel a bit overwhelmed by the information out there and the different ways people construct these things. In fact, there's just not a lot of comprehensive info. Maybe with my photos and some input, we could have a thread that provides such info, and in the process, I'll be able to finish this mic.
Any help will be greatly appreciated!
Thank You
Sean Harris
Tim Campbell's response:
Sean,
There has been a lot of mention on the internet about the use of EF42 tubes being similar to EF12/VF14's. This must be a case of one person misidentifying a tube and others repeating this until it's perceived as fact.
I have tried to use EF42's as audio tubes and found it impossible. They have some wonderful qualities for audio but are inherently so microphonic as to render them unusable. If you like the EF12 use an EF12 or try an EF40 or the EF184.
Klaus's response:
Sean, I admire and encourage your explorations. It is through tinkerers like you that the conventional approach to designing good recording microphones will one day be eclipsed.
However, why try to re-invent the wheel, and use parts and design approaches that plenty of vintage mic cloners already pursue? Why not try something new?
If your intent is to build a decent copy of a U47 mic, there are easier and less costly ways. Numerous manufacturers offer either all the parts to do that, or will sell you pre-assembled copies that contain most of the parts you mentioned, and at reasonable prices. (By the way: Neumann does not reskin its capsules, so I am not sure what was sold to you as such.)
If your intent is to make a superior recording mic, I would venture to say that using the same copy parts that are commonly used to build a passable mic that is not quite capable of delivering the sonic quality of the real thing also makes little sense to me.
Either the wheel is perfectly round, and all we can do is tinker at the edges, or new designs are waiting to be explored and tested. I hope you can be a part of the group that is trying the latter.
Best of luck, and lots of courage!
My response:
Thank you Tim and Klaus your responses. I will see that we acquire an EF12, EF40, or EF184 tube. This acquisition of parts was a very good deal from a monetary standpoint. There are many parts including several mic bottles, wima caps, several chinese capsules and various transformers (1 hauffe and 2 chinese). I stand corrected Klaus. I re-read the e-mail, and the claim was that it was serviced by a Beumann Germany technician, not by the Neumann itself. I am dubious about that claim as well, but who knows? Anyway, I have accepted this task as a challenge and it is my intent to make a decent mic using the k47 capsule / hauffe transformer and mic bottle. I realize through reading on these forums that there are many kits available, but I kind of have to make mics out of what I currently have. There are schems on these forums for a k47/e12 mic, and from what I've read, the results are pleasing to most ears. Re-capturing "the original" is impossible without the k7/bv8/vf14 combination. (please forgive if my numbers are incorrect...I'm fresh here..)I also read through some posts talking about Hauffe tranformers being used as replacements by Neumann, but I'm sure that this is a new transformer, so sonically it won't be the same as a nos replacement or the original.
I just want to build a decent quality recording mic for my friends who have through went great trials and tribulations on a shoe string budget to build a small studio. I'm not doing this to re-invent the wheel...or exactly copy a U47.
When I get the parts in hand, I'll photograph them, and we'll see what kind of mess I got myself into...
The question now is...does anyone have a pcb layout for the k47 / e12 combination? Or, any other layouts? I have a sinking feeling that I'm going to spend a lot of time on a breadboard...
Any help is greatly appreciated!
Sean
Tim's response:
ean,
This isn't a mic builder's forum. Try asking the same questions here http://www.groupdiy.com/ . I'm sure you'll find the right kind of help and encouragement
Any help is appreciated!
Sean Harris
Well, here we go....I am new to the forum and have read a ton of material here. I feel very outclassed here being a lowly computer electronics tech whose knowledge is out of date. I have built and modified a ton of effects pedals and even one piece of studio gear. The studio that I'm involved in has purchased a mic bottle, a NOS K47 capsule re-diaphragmed by Neumann, a NOS EF42 tube, and a Hauffe transformer. Also, a PSU spec'd for 105 volt output.
I was wondering if anyone had a schematic that would give me a starting point in order to build this thing? Maybe even a pcb layout, or point me to someone who could sell me pcb's for this project?
From what I understand, the EF42 is a pin for pin replacement for the EF12. I would like to post photos and have a lot of input from the forum about completing this project.
Questions and comments are welcome, as I feel a bit overwhelmed by the information out there and the different ways people construct these things. In fact, there's just not a lot of comprehensive info. Maybe with my photos and some input, we could have a thread that provides such info, and in the process, I'll be able to finish this mic.
Any help will be greatly appreciated!
Thank You
Sean Harris
Tim Campbell's response:
Sean,
There has been a lot of mention on the internet about the use of EF42 tubes being similar to EF12/VF14's. This must be a case of one person misidentifying a tube and others repeating this until it's perceived as fact.
I have tried to use EF42's as audio tubes and found it impossible. They have some wonderful qualities for audio but are inherently so microphonic as to render them unusable. If you like the EF12 use an EF12 or try an EF40 or the EF184.
Klaus's response:
Sean, I admire and encourage your explorations. It is through tinkerers like you that the conventional approach to designing good recording microphones will one day be eclipsed.
However, why try to re-invent the wheel, and use parts and design approaches that plenty of vintage mic cloners already pursue? Why not try something new?
If your intent is to build a decent copy of a U47 mic, there are easier and less costly ways. Numerous manufacturers offer either all the parts to do that, or will sell you pre-assembled copies that contain most of the parts you mentioned, and at reasonable prices. (By the way: Neumann does not reskin its capsules, so I am not sure what was sold to you as such.)
If your intent is to make a superior recording mic, I would venture to say that using the same copy parts that are commonly used to build a passable mic that is not quite capable of delivering the sonic quality of the real thing also makes little sense to me.
Either the wheel is perfectly round, and all we can do is tinker at the edges, or new designs are waiting to be explored and tested. I hope you can be a part of the group that is trying the latter.
Best of luck, and lots of courage!
My response:
Thank you Tim and Klaus your responses. I will see that we acquire an EF12, EF40, or EF184 tube. This acquisition of parts was a very good deal from a monetary standpoint. There are many parts including several mic bottles, wima caps, several chinese capsules and various transformers (1 hauffe and 2 chinese). I stand corrected Klaus. I re-read the e-mail, and the claim was that it was serviced by a Beumann Germany technician, not by the Neumann itself. I am dubious about that claim as well, but who knows? Anyway, I have accepted this task as a challenge and it is my intent to make a decent mic using the k47 capsule / hauffe transformer and mic bottle. I realize through reading on these forums that there are many kits available, but I kind of have to make mics out of what I currently have. There are schems on these forums for a k47/e12 mic, and from what I've read, the results are pleasing to most ears. Re-capturing "the original" is impossible without the k7/bv8/vf14 combination. (please forgive if my numbers are incorrect...I'm fresh here..)I also read through some posts talking about Hauffe tranformers being used as replacements by Neumann, but I'm sure that this is a new transformer, so sonically it won't be the same as a nos replacement or the original.
I just want to build a decent quality recording mic for my friends who have through went great trials and tribulations on a shoe string budget to build a small studio. I'm not doing this to re-invent the wheel...or exactly copy a U47.
When I get the parts in hand, I'll photograph them, and we'll see what kind of mess I got myself into...
The question now is...does anyone have a pcb layout for the k47 / e12 combination? Or, any other layouts? I have a sinking feeling that I'm going to spend a lot of time on a breadboard...
Any help is greatly appreciated!
Sean
Tim's response:
ean,
This isn't a mic builder's forum. Try asking the same questions here http://www.groupdiy.com/ . I'm sure you'll find the right kind of help and encouragement
Any help is appreciated!
Sean Harris
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