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

[imo]

Yeah, it was a bit of running around for me. If I hadn’t already had the body, I would have stopped at the one.
I have 2 relatively similar 49s. Need to find a way to mount capsule in the micandmod body lower. It’s challenging because the mic hardware puts the capsule pretty high. My mount is short(7/8”) I’m gonna try to put some standoffs on the top board to see if I can buy an inch with a standoff

 

[HerbertR]

Yeah, it was a bit of running around for me. If I hadn’t already had the body, I would have stopped at the one.
I have 2 relatively similar 49s. Need to find a way to mount capsule in the micandmod body lower. It’s challenging because the mic hardware puts the capsule pretty high. My mount is short(7/8”) I’m gonna try to put some standoffs on the top board to see if I can buy an inch with a standoff

I also shortened the M&M M49 standoffs. I re-bent the 90 degree angles, re-drilled both mounting holes. Very simple.

 

[imo]

I also shortened the M&M M49 standoffs. I re-bent the 90 degree angles, re-drilled both mounting holes. Very simple.

That’s a good idea. Looks like 3/4” or so. That would put the capsule in a better spot in the headbasket

 

[Migs 31]

In case anyone is interested: View attachment 107554
you can email her at [email protected]

Hey @egroys

Thanks for the info mate!
Three are better than two.
See pictures attached.
MIgs

 

[egroys]

Hey @egroys

Thanks for the info mate!
Three are better than two.
See pictures attached.
MIgs

Yewwww! Gorgeous.

Do they fit the Poctop PCBs?

 

[Migs 31]

Yewwww! Gorgeous.

Do they fit the Poctop PCBs?

I can't tell as I don't have his PCB's.
I was thinking going P2P on these M49 bodies.
But they look very similar to @HerbertR 's in his last post of this thread.
M

 

[TLRT]

I did some acrilic boards for those cheaper m49 clone bodies,if anybody wants I can do more:

 

[bremusound]

Do these come with a nice AC701?

 

[TLRT]

Do these come with a nice AC701?

It has the price!

 

[soapF]

looks beautiful

 

[imo]

I had the chance in the past to compare some of my mics with real U67's and U47's to favorable results. It's interesting to hear them back to back. With both of those mics, we heard more variation in models than in the "real" vs "clone". I had access to Paul Allen's studio, and he had multiple mics of pretty much everything, as well as a world class studio to listen to them, so it was a great atmosphere to do that. Paul has passed, so the studio was shut down. I'd be really curious to hear the M49 variants. I really like mine with the 5840, and it has a nice full range. Neither seems peaky at all in the high end. In fact, I tend to put a bit of high end on mine as a rule to boost that 5k +

 

[JW]

I'm mostly using Dany's BOM, but plan to build my PSU out on tag board. Anyway, this TBone PSU case looks nice and i can use the power inlet, probably the power switch and maybe even the connectors.
https://www.thomann.de/gb/the_t.bone_psu_retro_tube_ii.htm

The schematic is on this page:
https://groupdiy.com/threads/alctron-bv300-t-bone-retro-tube-ii-to-half-of-akg-c24-mod.47042/

I'm curious if i can utilize the power transformer, to bring down cost further. In fact, it looks like two power transformers to generate B+ and heater? It would be very nice if that TBone transformer had what it takes to power both B+ and heater, assuming I'm using the M49B PSU schematic on the first page of this thread.

Does this seem like a workable plan?

 

[garp]

Does this seem like a workable plan?

Yes it is ! I just did it. Only 4 resistors had to be changed on dan's schematic (the two 6k became Two 18k or 20k and the two 22r changed for two 10r same wattage of course) you should be able to trim both 6,3v and B+.

 

[garp]

 

[garp]

Note that you'll have to tie the remaing leg of the heater trimmer to the potentiometer chassis to minimise ground problems. The M49b PSU is known to be tricky to ground and filter, this is a process that can be irritating and time consuming. When properly done only remains the PSU and tube inherent noise (can be also improved with a cardioid only arrangement on the mic). Of course a separate B+ switch has been added to avoid any tube stress at start.

 

[JW]

Hmmm. No choke though, right? Or is there only one power transformer with multiple secondaries?

 

[garp]

One power transformer with multiple secondaries, the one provided with the psu. It has dual 175v 9,5v output when the PCB is waiting 120V 20V, so a few resitors had to be changed to spot the right tensions without changing too much the design. Thanks @Emmathom helping resolve the puzzle !

 

[egroys]

I know this isn't the quietest circuit, but are there any tips to lower the noise floor in this baby? I have the 'C' version and I LOVE it on room mic duties. For quieter sources I end up boosting a decent amount and then I have to RX the noise floor. I would love to know if there is anything I can do to lower it naturally.

Also, I have some Soviet PIO caps but they are 160V. Safe or no good?
Thank you!

 

[Moby]

I know this isn't the quietest circuit, but are there any tips to lower the noise floor in this baby? I have the 'C' version and I LOVE it on room mic duties. For quieter sources I end up boosting a decent amount and then I have to RX the noise floor. I would love to know if there is anything I can do to lower it naturally.

Also, I have some Soviet PIO caps but they are 160V. Safe or no good?
Thank you!

Noise depends from the tube. You should select the lowest noise tube.

Regarding the PIO cap's, before you use them be sure that they are not leaky. Especially at the hi voltage, in this case 116V. Are you are using the regulated or RC filtering power supply for the HV? If it's regulated and cap is not leaky you are safe to go with the 160V cap. If it's RC psu filtering than you are on the edge with the 160v rated capacitor and 250v is recommended.

 

[egroys]

Noise depends from the tube. You should select the lowest noise tube.

Regarding the PIO cap's, before you use them be sure that they are not leaky. Especially at the hi voltage, in this case 116V. Are you are using the regulated or RC filtering power supply for the HV? If it's regulated and cap is not leaky you are safe to go with the 160V cap. If it's RC psu filtering than you are on the edge with the 160v rated capacitor and 250v is recommended.

Understood and thank you, Srdjan. I'm using 6S6B-V's and they are all about the same noise level out of the 5 or 6 I've tested. Maybe it's worth trying some 5718ws's?

I have the PSU from Dany's kit so I believe it's unregulated. The cap doesn't appear leaky but it's probably better to not risk it in this case...