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

[Delta Sigma]

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?

Careful there. It's likely that your heater transformer won't be able to provide the current unless you used an LED bulb. I've had trouble finding LED bayonets at a reasonable price. I wanted to use Fender style pilot lights just because I have them on hand with multiple jewel colours. I ended up using 120VAC because I found 120VAC LED bulbs but unfortunately, they put off a lot of heat.

 

[egroys]

Careful there. It's likely that your heater transformer won't be able to provide the current unless you used an LED bulb. I've had trouble finding LED bayonets at a reasonable price. I wanted to use Fender style pilot lights just because I have them on hand with multiple jewel colours. I ended up using 120VAC because I found 120VAC LED bulbs but unfortunately, they put off a lot of heat.

Copy.
I did grab #47 LED bulbs. Am I correct to tap it from pin 4 & 7?

But I also have a regular 6.3v lamp I was told I could potentially use as a dummy load on the H+ for tuning.
Can anyone verify that?

Otherwise, I'm just about ready to start tuning it sans-capsule! Waiting on Dany's D7.

Not too shabby for a first build?

 

[Purplenoise]

Copy.
I did grab #47 LED bulbs. Am I correct to tap it from pin 4 & 7?

But I also have a regular 6.3v lamp I was told I could potentially use as a dummy load on the H+ for tuning.
Can anyone verify that?

Otherwise, I'm just about ready to start tuning it sans-capsule! Waiting on Dany's D7.

Not too shabby for a first build?
View attachment 80729

Looks good man

 

[garp]

I am planning to use the beesneez bv11 for this build, is the pcb suitable for this tranny or should i have to wire it manually ?

 

[Purplenoise]

I am planning to use the beesneez bv11 for this build, is the pcb suitable for this tranny or should i have to wire it manually ?

Manually…which is actually easier. 4 wires on main pcb. You will use the bottom pcb for support…maybe even drill a couple of extra holes to securely strap the transformer in place. Just make sure you take under consideration the output cap size/placement

 

[garp]

Thanks a lot ! Now i have to find where primary and secondary are, there are no markings on it

 

[Purplenoise]

Thanks a lot ! Now i have to find where primary and secondary are, there are no markings on it

Doesn’t beesneez provide a wiring diagram? You should ask them

 

[garp]

When i bridge some pins as indicated underneath bobin with red and blue markings and i measure the other pins i have around 1k across 2 pins and 20 ohms across the 2 others making me thinking that the first pair goes to pcb and the two others (lowest resistance) goes to the output right ? Well ... it's not very clear maybe ! when looking at the transformer pin facing me i count 6 pins in two groups of 3 upper side and 6 pins under . on the upper side i have a pencil mark joining in red pin 1 and 4 (from left to right ) and 3 / 6 in blue.
When i measure the "under" pins i have 1k between 7 and 10 and 20 ohm between 9 and 12 .
edit : according to this it seems that i can use Dan's pcb ...

 

[egroys]

So my pair of 49c's has been working brilliantly for almost 2 months. Keeps beating out everything I have on female vocals!

I began to notice noise during a vocal session today (soft singer, very high gain on a 1073 clone). It sounded like a candy wrapper gently being crumpled right up on the mic. No pattern to it but it's now happening consistently. I typically heat the mic for an hour + before a session.
Not hearing anything in the other 49.

How likely is it that my 6S6B-V is on the fritz? I live in Los Angeles so I doubt that it's humidity...

Also, does is it a good/bad idea to be powering my PSU's through a UPS (CyberPower 900va AVR)?

 

[Purplenoise]

So my pair of 49c's has been working brilliantly for almost 2 months. Keeps beating out everything I have on female vocals!

I began to notice noise during a vocal session today (soft singer, very high gain on a 1073 clone). It sounded like a candy wrapper gently being crumpled right up on the mic. No pattern to it but it's now happening consistently. I typically heat the mic for an hour + before a session.
Not hearing anything in the other 49.

How likely is it that my 6S6B-V is on the fritz? I live in Los Angeles so I doubt that it's humidity...

Also, does is it a good/bad idea to be powering my PSU's through a UPS (CyberPower 900va AVR)?

It’s not uncommon for a tube to be defective. I would try switching the cable first to eliminate that there is not a bad contact in the cable itself. I guess you have two cables right?
It could also be the capsule…you could easily find out by switching capsules.

 

[Delta Sigma]

So my pair of 49c's has been working brilliantly for almost 2 months. Keeps beating out everything I have on female vocals!

I began to notice noise during a vocal session today (soft singer, very high gain on a 1073 clone). It sounded like a candy wrapper gently being crumpled right up on the mic. No pattern to it but it's now happening consistently. I typically heat the mic for an hour + before a session.
Not hearing anything in the other 49.

How likely is it that my 6S6B-V is on the fritz? I live in Los Angeles so I doubt that it's humidity...

Also, does is it a good/bad idea to be powering my PSU's through a UPS (CyberPower 900va AVR)?

I had the same thing happen with my 6S6B.

Strangely, I replaced it with the 5840 that lost the original shootout and preferred the 5840 this time around. The 6S6B has this low-mid richness that is so very appealing in a shootout. The 5840, however, has a nicer top end and I felt that the 5840 worked better in a mix.

Anyway, given the frustration of swapping out a leaded tube, plus burning the burning in period, I'm happy to use the seemingly more reliable 5840.

 

[egroys]

Thank you, gentlemen. I checked the cable before ultimately changing the tube. Sounds great now.

Curious if anyone had issues centering the capsule due to the need to carve some of the lowest PCB to fit the Studio 939 body?
How much does that matter if it's only slightly off center?

 

[sedrec1]

Thank you, gentlemen. I checked the cable before ultimately changing the tube. Sounds great now.

Curious if anyone had issues centering the capsule due to the need to carve some of the lowest PCB to fit the Studio 939 body?
How much does that matter if it's only slightly off center?

Is there any PSU that would work with the D49 without having to build one?

@egroys I am also looking at the Studio 939 body would be interested if you have any trouble with this, in terms of fitting it in or actual usage?

Thanks

 

[JMPGuitars]

Is there any PSU that would work with the D49 without having to build one?

@egroys I am also looking at the Studio 939 body would be interested if you have any trouble with this, in terms of fitting it in or actual usage?

Thanks

I had no trouble with Chunger's mic body at all. I made an acrylic mounting plate for the bottom of the body mounting. I actually have a laser cutter now, if there was enough interest, I could make a bunch of the mounting plates for people.

Thanks,
Josh

 

[dmp]

I did grab #47 LED bulbs. Am I correct to tap it from pin 4 & 7?

But I also have a regular 6.3v lamp I was told I could potentially use as a dummy load on the H+ for tuning.
Can anyone verify that?

There are 120v bayonet bulbs that fit in the fender style pilot lights. I've use these on mic psus to avoid taking the excess heater current. I bought them on Mouser, I think.
I think the standard 6.3v #44 bulb draws 250 mA, which is similar, but higher, than what a tube heater draws (5940 tube: 150 mA Heater current). But with a passive heater filter circuit like in the M49 psu, you need to set the heater voltage with the actual current draw - at higher currents you will get more voltage drop. If it were a regulated voltage then you could set it with a dummy load, but not here.
If you are running a build off the heater voltage, then yes, H+ is p4 and 0v is p7

 

[egroys]

I had no trouble with Chunger's mic body at all. I made an acrylic mounting plate for the bottom of the body mounting. I actually have a laser cutter now, if there was enough interest, I could make a bunch of the mounting plates for people.

Thanks,
Josh

I would take two! How much would you charge + shipping to Los Angeles?

 

[egroys]

Is there any PSU that would work with the D49 without having to build one?

@egroys I am also looking at the Studio 939 body would be interested if you have any trouble with this, in terms of fitting it in or actual usage?

Thanks

Not sure about the PSU but my impression is no.
The body is fantastic but I ended up having to carve the blank PCB to fit between some body screws so it's not super even.

 

[rmburrow]

Not sure about the PSU but my impression is no.
The body is fantastic but I ended up having to carve the blank PCB to fit between some body screws so it's not super even.

D-49 power supply: Clone a Neumann NKM supply or the Altec supply for the M-30 lipstick mic. I like the NKM supply since it has a regulator tube (150B2) holding HT to 150 volts through a series resistor off the rectifier bridge. The American 0A2 will also work with a pin change. The d.c. heater voltage is heavily filtered. The NKM was originally built for the AC701 tube with a 4 volt heater, but this can be easily changed for 6 volts. In my NKM supply, I replaced the stabilyte cells with AA rechargeable batteries (need 4 in series for 6 v). Looking for dimensionally correct M49 bodies for my builds.

 

[JMPGuitars]

I would take two! How much would you charge + shipping to Los Angeles?

I don't know what they're worth to people, so I don't know if it's worth doing. If some people could chime in with what they think a fair price for these plates would be, and if there's interest in them.

Thanks,
Josh

 

[JMPGuitars]

After some discussion, it seems like $25 each for 1, or $20 each for 2 or more, plus shipping would be fair. So probably about $45 shipped for a pair within continental US (or a few bucks more for Priority Mail).

I've already converted my previous drilling guide I designed to a laser burning file, and I'm going to test this out on some acrylic material and see how it goes. I'll share a photo of the results.

EDIT: It looks good.
The text is a little goofy, I forgot to change one of the engraving settings. Oops. Otherwise, it matches my template that I used on my M49 build perfectly. This looks a LOT better than the one I hand drilled.


Thanks,
Josh