Neumann M49 Clone : Build Thread Puck Style (TLM49 Conversion To M49 b-c)

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After trying plenty of capacitors on the output I have found one that made a really nice difference. It is a little expensive and many might feel that it’s foolish to spend so much on a cap but...i really like what I heard. The sound became more effortless and less constricted, more 3D and smoother/balanced. Not in a way of “adding” something but rather subtracting...more transparency.
The cap is the V-CAP OIMP. I will try one also in my d-ef47 build.
 
I was hoping to get a little more PSU guidance.
***This is my first tube mic build but I do have someone very qualified that will be walking me through the high-voltage parts of the build***

The build guide is so detailed with the mic PCB but there are only two photo's of the PSU and there's only so much info I can get visually. And the 'Ultimate PSU' thread's photo's are missing save for a few at the end!

I've received everything (but the capsule) and I stuffed and soldered the PSU PCB.
I purchased the Collective Cases PSU and am now realizing that the BOM did not include mounting hardware and that I have to drill my own holes.

I am hoping to learn and see what anyone with the Collective Cases PSU had to get to complete the PSU?

I am missing:
- Screws to mount the IEC/XLR's
- All mounting hardware for the trafo's, choke, potentiometer, etc.
- Not even sure what else!

Any guidance would be greatly appreciated!

Thank you in advance!
 
egroys said:
I was hoping to get a little more PSU guidance.
***This is my first tube mic build but I do have someone very qualified that will be walking me through the high-voltage parts of the build***

The build guide is so detailed with the mic PCB but there are only two photo's of the PSU and there's only so much info I can get visually. And the 'Ultimate PSU' thread's photo's are missing save for a few at the end!

I've received everything (but the capsule) and I stuffed and soldered the PSU PCB.
I purchased the Collective Cases PSU and am now realizing that the BOM did not include mounting hardware and that I have to drill my own holes.

I am hoping to learn and see what anyone with the Collective Cases PSU had to get to complete the PSU?

I am missing:
- Screws to mount the IEC/XLR's
- All mounting hardware for the trafo's, choke, potentiometer, etc.
- Not even sure what else!

Any guidance would be greatly appreciated!

Thank you in advance!
Look at the D67 psu build guide ( pictorial) at vintagemicpcbkit. Very good tips for mounting the components. For the steel mounting bars you can get thin steel bars used for making knife blades from Amazon but you will need to do cutting, bending and drilling. Maybe also a kit with assortment of screws and nuts/bolts from Amazon is a good idea too.
 
Purplenoise said:
Look at the D67 psu build guide ( pictorial) at vintagemicpcbkit. Very good tips for mounting the components. For the steel mounting bars you can get thin steel bars used for making knife blades from Amazon but you will need to do cutting, bending and drilling. Maybe also a kit with assortment of screws and nuts/bolts from Amazon is a good idea too.

That's super helpful! Thank you!

And I also read about omitting/changing the value of C4? I have a 6S6B-V. Would that have an impact on the value?
 
egroys said:
That's super helpful! Thank you!

And I also read about omitting/changing the value of C4? I have a 6S6B-V. Would that have an impact on the value?

Start with something like 4pF. Record a test, then reduce its value and record, then omit C4 and record. Decide immediately which one you like best, then relisten a day or two later and realize you're wrong.

At least that's how I do component changes.

Do the same with C6 and R3. Though, increase the value of R3 (and omit); don't decrease.
 
egroys said:
That's super helpful! Thank you!

And I also read about omitting/changing the value of C4? I have a 6S6B-V. Would that have an impact on the value?
The purest and loudest is without C4. You might find it a little “hairy”. As delta sigma suggested compare different values and see what works best for your mic. With c4 on the level is quieter and the sound cleaner.
 
Makes sense.

If I do omit C4 (hairy sounds much more my flavor than simply clean...) do I need to make a jumper or anything like that? Or just leave it empty?
 
egroys said:
Makes sense.

If I do omit C4 (hairy sounds much more my flavor than simply clean...) do I need to make a jumper or anything like that? Or just leave it empty?

Just leave it empty.
 
egroys said:
Makes sense.

If I do omit C4 (hairy sounds much more my flavor than simply clean...) do I need to make a jumper or anything like that? Or just leave it empty?

Hairy is the reason I build these big ol tube and transformer designs. I love character and omitting C4, C6 and R3 gets you more character. Best bet is to hear the changes for yourself though.
 
Delta Sigma said:
Hairy is the reason I build these big ol tube and transformer designs. I love character and omitting C4, C6 and R3 gets you more character. Best bet is to hear the changes for yourself though.

Here Here!!

Ok, so I've figured out the steel brackets and am moving on swimmingly!

I wanted to see if anyone with the Moby BV11 could clue me in on the correct connections? The TX PCB appears to be reversible between the AMI and MX trafos?

Also, I got my 6S6B-V wired in A, H+, HG, FGrid, K (1-5 respectively). Are you all just leaving the tube hanging on the PCB or do I need to pad it somehow?


Getting close!
Thank you all for the guidance! This community is absolutely brilliant!
 
egroys said:
Here Here!!

Ok, so I've figured out the steel brackets and am moving on swimmingly!

I wanted to see if anyone with the Moby BV11 could clue me in on the correct connections? The TX PCB appears to be reversible between the AMI and MX trafos?

Also, I got my 6S6B-V wired in A, H+, HG, FGrid, K (1-5 respectively). Are you all just leaving the tube hanging on the PCB or do I need to pad it somehow?


Getting close!
Thank you all for the guidance! This community is absolutely brilliant!
For the Moby bv11 it is:
A green
B red
D black
C yellow

Be careful because the order on the pcb is A B D C. It’s easy to mistake it for abcd.
 
Purplenoise said:
For the Moby bv11 it is:
A green
B red
D black
C yellow

Be careful because the order on the pcb is A B D C. It’s easy to mistake it for abcd.

Copy that. Based on looking at the OG schematic, do the Blue/White leads go to inside pads like in the attached photo?

Also, how did you mount your Moby? Upside down on the PCB since the screws come protrude quite a bit, I imagine? And if so, how are you strapping that sucker down?

Getting close!
 

Attachments

  • Moby M49 wiring.jpg
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egroys said:
Copy that. Based on looking at the OG schematic, do the Blue/White leads go to inside pads like in the attached photo?

Also, how did you mount your Moby? Upside down on the PCB since the screws come protrude quite a bit, I imagine? And if so, how are you strapping that sucker down?

Getting close!
You don’t have to connect anything on that pcb. Just use this pcb to support the transformer with zip ties ( even if you need to make an extra hole or two) and connect the wires straight to the main component pcb. Just be careful of orientation and placement of the transformer so that you have space for the output capacitor ( 1uf 250v)
 
Purplenoise said:
You don’t have to connect anything on that pcb. Just use this pcb to support the transformer with zip ties ( even if you need to make an extra hole or two) and connect the wires straight to the main component pcb. Just be careful of orientation and placement of the transformer so that you have space for the output capacitor ( 1uf 250v)

I see. And the white and blue leads?
 
egroys said:
I see. And the white and blue leads?
You connect blue to blue together and white to white. They don’t go anywhere. I have attached the wiring scheme.
 

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That's what I figured. Thanks for clarifying!

I got the the traffo strapped and wired, C5 in, and now I am for the first time seeing that my PCB stack is not fitting in the body. It's a chunger M49 body but the screws for the spacers bump the sides.

I'm not sure what body Dany is using in the build pics but there appears to be some addition plate below the traffo PCB.

Any clues/tips on how to make this fella sit right?
 
egroys said:
That's what I figured. Thanks for clarifying!

I got the the traffo strapped and wired, C5 in, and now I am for the first time seeing that my PCB stack is not fitting in the body. It's a chunger M49 body but the screws for the spacers bump the sides.

I'm not sure what body Dany is using in the build pics but there appears to be some addition plate below the traffo PCB.

Any clues/tips on how to make this fella sit right?
The easiest way is to make dents at the side of the pcb and use a nut for support. I am attaching a pic to see what I mean.
 

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I am noticing Dany's link to the cabling connection pinout is no longer working (https://cdn.groupbuilder.com/groupdiy/u/39511/58d1402a053d6.jpg)

I just want to double check this.
I am using GAC-7 and will be terminating Binder female at the mic to XLR male at the PSU end.

1 - Audio + (white)
2 - Audio - (black)
3 - No connection?
4 - Heater (red)
5 - B+ (yellow)
6 - Polar Pattern switch (green)
7 - Ground (blue)

Then I believe it is shield AND gray to the shell?
Do I need to jumper anything on the mic end?
I feel like when I first examined that (now broken) link, there was something regarding pin 3 and 7 being reversed on the mic end?

Thank you in advance again!

I owe several of you beers!!
 
egroys said:
I am noticing Dany's link to the cabling connection pinout is no longer working (https://cdn.groupbuilder.com/groupdiy/u/39511/58d1402a053d6.jpg)

I just want to double check this.
I am using GAC-7 and will be terminating Binder female at the mic to XLR male at the PSU end.

1 - Audio + (white)
2 - Audio - (black)
3 - No connection?
4 - Heater (red)
5 - B+ (yellow)
6 - Polar Pattern switch (green)
7 - Ground (blue)

Then I believe it is shield AND gray to the shell?
Do I need to jumper anything on the mic end?
I feel like when I first examined that (now broken) link, there was something regarding pin 3 and 7 being reversed on the mic end?

Thank you in advance again!

I owe several of you beers!!

Do you have the schematics printed? I think you're right about pin 3/7. You could also just take a close look at your power supply and mic to determine which pins. Colour code chosen will not matter to anyone but you. Just make sure you use the larger gauge wires for H+ and 0V.
 
Has anyone used a Fender style 6.3V pilot light?

I am not sure where to connect the bugger...
Should I be tapping h+ on from the pot or from pin 4 on the PSU?
 
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