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

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We all do that, most of the info I of stuff have built are from internet. But the good thing about this forum and others is that much of the DIY stuff differes in many ways, therefore it's sometimes assuring to be able to ask people who, presumably, know better than you. If you know the answer, answer it. Why not?
Your point about not answering questions directly is valid in general. Forums are full of strange gatekeeping meant more to build egos than to help. In this case, there are a few things that make this forum different.

Many projects (like those from poctop, Matador) have detailed instructions at the beginning of build threads. Building a microphone can be very difficult and frustrating. After reading all the instructions at the start of the thread, many members are still stuck and come to these threads with questions. These questions and answers are quite helpful for others reading the threads.

The problem, is that when people keep asking questions that have already been answered or the answer could have been found by reading post #1. This makes build threads so long that they are unusable (and frustrates those who answer the same questions over and over).

A good example is the mic troubleshooting sticky that was just started. The intention is to have only posts with basic troubleshooting info/techniques. There are now 14 posts and only two or three are actual tips. It's a brand new thread and it's already becoming unusable.

DIY is a very deep dive; there is lots to learn. The forum helps us all skip many steps but its purpose isn't to help skip all steps.
 
Sorry for that, missed it.
There's a certain snobbishness from some members that I apologize on their behalf for, which they will not agree to.

Sometimes when ppl get too knowledgeable it's just irritating for them to reply kindly to simple questions they think you should know, and it's easier to say "go do it yourself" - it would be far better if they just wouldn't respond, as it's rude and it wastes everyone's time. You know who you are.

There is a fine line between being proactive and learning and then asking the community to solve all your problems for you, so in their defense, some cross this line too much and then it is a genuine irritation. I don't think there's a clear answer here; what I do is try my hardest to find the answer on my own, and they if I must, I ask, and even then I've gotten ripped a few times. But it is what it is.

In any case, I'm glad you're here, and I hope you find the answers you are looking for.

Mike
 
5840 so far:
Lead 1 connects to the grid circuit.
Lead 2 connects to the cathode circuit. Just tape off leads 4 and 8 since they are
internally connected to lead 2.
Connect leads 5 and 7 together. This makes the tube a triode. Connect the two leads to the plate circuit.
Connect leads 3 and 6 to the 6.3V filament supply.
 
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Just received my 3U M7 capsule and after some fiddling to get the height where I wanted it, it's in and sounds excellent in this circuit.

Will hopefully have some time in an upcoming session to get this compared back-to-back with my Peluso P49 (Sadly the OG '50s M49 had to go back to the client 😭)IMG_4847.jpegIMG_4848.jpeg
 
Just received my 3U M7 capsule and after some fiddling to get the height where I wanted it, it's in and sounds excellent in this circuit.

Will hopefully have some time in an upcoming session to get this compared back-to-back with my Peluso P49 (Sadly the OG '50s M49 had to go back to the client 😭)View attachment 102987View attachment 102988
Awesome! Looks great. Where did you get your mic body? I am sort of wondering how I will mount mine. I bought a nice looking M49 case this week from ShuaiYin but I don't know if it will come with the acrylic mounting thing you see in Dan's photos. Also, cool to know your 3U capsule sounds good. I'm not sure where I will get an m7 capsule yet. Did you use the 5840 tube?

I was wondering; What heights did you use for the standoff spacers?

Thanks!
 
I received my m49 mic body from Shuai Yin. It’s different than the one they sent me pictures of, but if’s beautiful and I’m very impressed with the quality of this body. I guess it looks exactly the same as the one from Mic & Mod (I did not buy this from them! I am aware of the darkness that company has with the forum…) But I wanted to ask: I purchased the round PCB’s for this build from Dany. Will the round PCB fit into this body? Seems like it will, right? There’s a standoff spacer hanging down from the top of the body under the capsule mounting base. I just wanted to make sure it’ll work for Dany’s M49 build. Thanks!

Also, are people generally preferring the 5840 C version of this build, or the 6s6b-V tube variation? I feel like I want to just stick with what Dany used for his original build since I know that works with his design. But I’m open to opinions about tube choice and adjustments if tone is improved.

For the 5840, what brand tube is recommended for this build?

I have read a fair amount of this thread but I will read the whole thing before commencing my build, So stoked to make one! I got Dang’s M7 capsule for this build, which I’m sure will be great.
 

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I received my m49 mic body from Shuai Yin. It’s different than the one they sent me pictures of, but if’s beautiful and I’m very impressed with the quality of this body. I guess it looks exactly the same as the one from Mic & Mod (I did not buy this from them! I am aware of the darkness that company has with the forum…) But I wanted to ask: I purchased the round PCB’s for this build from Dany. Will the round PCB fit into this body? Seems like it will, right? There’s a standoff spacer hanging down from the top of the body under the capsule mounting base. I just wanted to make sure it’ll work for Dany’s M49 build. Thanks!

Also, are people generally preferring the 5840 C version of this build, or the 6s6b-V tube variation? I feel like I want to just stick with what Dany used for his original build since I know that works with his design. But I’m open to opinions about tube choice and adjustments if tone is improved.

For the 5840, what brand tube is recommended for this build?

I have read a fair amount of this thread but I will read the whole thing before commencing my build, So stoked to make one! I got Dang’s M7 capsule for this build, which I’m sure will be great.
Ok so I was actually just gonna ask where you got YOUR mic body 😆 Mine was the Chunger one from a while back, I'm not sure if they're still available? They included the binder connection as well which was an awesome deal.

I did use the 5840 for my build. There's no shortage of them and they're cheap enough so you can always grab a bunch and roll em till you get the quietest and best sounding.

Standoffs were I think 5/8" and 3/8" for the bottom and top section respectively. But The heights weren't "perfect" so i might end up tweaking that down the road.
 
Ok so I was actually just gonna ask where you got YOUR mic body 😆 Mine was the Chunger one from a while back, I'm not sure if they're still available? They included the binder connection as well which was an awesome deal.

I did use the 5840 for my build. There's no shortage of them and they're cheap enough so you can always grab a bunch and roll em till you get the quietest and best sounding.

Standoffs were I think 5/8" and 3/8" for the bottom and top section respectively. But The heights weren't "perfect" so i might end up tweaking that down the road.
Thanks! Super helpful. Yeah, I looked on Chunger’s site, but it isn’t available right now so I just sourced this one myself! I’ll buy Chunger’s u47 and u67 cases though they still seem to be there. I wish mine had the binder connector but it doesn’t and looks like you can’t switch this style body’s lower section out.

Thanks for the help! I’ll try that spacer setup first.
 
I need some help! I have this cool looking m49 body I bought from ShauiYin and I didn't realize the mounting chassis would be like this because the photos they sent me of the body were different than what the one I received looks like. The photos looked like Chunger's body. This one looks like the one from the infamous Mic & Mod which uses a smaller round pcb set than the one I ordered from Dany which is 60mm diameter. Obviously I want to use Dany's PCB set from this thread with it.

Thankfully the mic body is more like 65mm inside or 66mm in some spots, so the round PCB's (60mm) will fit. But I don't know how I am going to mount the circuit internally yet.

The body came with an internal chassis which is only about 55mm inside.

I ordered Dany's M7 with the 58mm mount. Roughly measuring it it should be possible to mount the top capsule PCB onto the lip of the headbasket and have it be pretty centered in the headbasket grille.

But the top lip screws are 65mm apart. I suppose I'd have to use small adapters to make it fit somehow. The XLR base and the bottom of the mic are a screw on affair as opposed to the usual screwed mounting system m49 bodies usually use.

I could also potentially remove the chassis from the XLR base and mount the headbasket to the circuit and use precisely measured standoffs to make sure the bottom of the circuit ends up exactly where it needs to for the XLR base cover to screw onto the bottom of the mic correctly.

Does anyone have a better idea though? That's why I'm posting this with all the pictures... I don't have the PCB's yet, still waiting on delivery, otherwise this might be a little clearer... I want to order any adapters or spacers I'll need though so would be great if someone has some ideas! Thanks!
 

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what is the model number you used from Shuai Yin?

thanks
They didn’t provide me with one. No packing sheet in the box either. They just sent me pictures, which looked exactly like Chunger’s body with the set screw holding the bottom on which I wanted because I could’ve switched out the XLR with a Binder-XLR case bottom from AMI. But then when it arrived, it was a different body with a screw-on bottom and only regular XLR as an option. They did advise me it was an XLR only version. No part numbers were ever provided. I am still happy with the purchase, although Poctop’s round PCB’s do not fit this body’s frame (55mm internal frame, 60mm diameter PCB’s.) The internal diameter of the entire body is almost 70mm though so the build will still fit inside, but I will have to do some hardware DIY’ing to get the finished PCB build to fit internally and be mounted securely in the body, but I already have some plans and it shouldn’t be too difficult. I would recommend just going with Chunger’s body at Studio 939 storefront but it is currently out of stock. Not sure who makes that particular one as OEM, sorry.
 
The only suggestion that come to mind is in the c version with the 5840 the cathode bypass cap specified at 22uf(25uf) can be replaced with a 10uf for better bass response IIRC, still needs to be tested here.

the Psu is also full passive split choke so no issue with the B version at all , and the heater can be adjusted for proper voltage for the AC701 if you have one ,
in hand ,

Best,
Dan,
Hey guys! I have a question for those who have built the m49. It relates to this quote from Dan. I am going to use Moby's Bv.11 Tx and a 5840w tube, most likely. Would you guys recommend doing this mod above where you use the 10uf cathode bypass cap instead of 22uf for better matched low end response on the 5840w which I have read is brighter than the ac701 was?

Or would you guys recommend trying to source 6s6b-v tubes instead? 50840's are a lot easier to get here... (US).

Thanks!

Matt
 
Hey guys! I have a question for those who have built the m49. It relates to this quote from Dan. I am going to use Moby's Bv.11 Tx and a 5840w tube, most likely. Would you guys recommend doing this mod above where you use the 10uf cathode bypass cap instead of 22uf for better matched low end response on the 5840w which I have read is brighter than the ac701 was?
It seems counter-intuitive that going to half the cathode bypass capacitance would give you "better" bass. "Brightness" would not be addressed by this change, and I can't see why raising the low frequency cut-off by more than an octave would compensate in a manner that would be appealing. However, there can be situations where using a smaller OUTPUT capacitor raises the resonant bump that occurs as a result of the cap-transformer interaction and if that bump comes up into the 30-40HZ range, it can sound like there's more bass, because, in that specific region, there is. But BELOW the resonant bump your mic will roll-off at (at least) 6dB/octave. Have some fun and try replacing the cathode resistor and bypass cap(s) with two UF4007 diodes in series (negative to ground). I think you'll like it!
 
I built a pair of these 2 years ago and they have been amazing.

After moving mid 2022, they spent a few months in storage. I finally pulled them out, got them recalibrated to my new studios power and am noticing one of them sounds quite different than the other; one is meaty and bit dark and the other is a little thinner and bright, but neither in a necessarily bad way.

The builds are identical and all of my measurements, H+, B+, and bias are all measuring near identically.

What could have changed? Something with the capsule?
 
I built a pair of these 2 years ago and they have been amazing.

After moving mid 2022, they spent a few months in storage. I finally pulled them out, got them recalibrated to my new studios power and am noticing one of them sounds quite different than the other; one is meaty and bit dark and the other is a little thinner and bright, but neither in a necessarily bad way.

The builds are identical and all of my measurements, H+, B+, and bias are all measuring near identically.

What could have changed? Something with the capsule?
Are the capsule leads close together or closer to the mic body on the thinner sounding one?
 
Are the capsule leads close together or closer to the mic body on the thinner sounding one?
I'm going to check on that shortly. What I did find, during a session with my 47 today, that my XLR cable was making that mic sound thin! So the thin part is solved and I have a cable to fix.

However, I did a very quick 49 comparison with 2 identical preamps and found that my second mic, although no-longer thin, is about 2db quieter and has a little bit more high end. I crossed preamp channels just to be sure.

Can this still have to do with the capsule leads?

Thank you!
 
Possible, though not terribly likely. I built a 251 in a Beesneez body. There's a fairly big chunk of brass to get through from the capsule. I first built it with the backplates and rear capsule leads all going through the same hole. I rewired it with each lead going through its own hole and with some PTFE tubing around the leads and smaller gauge wire. It was a very noticeable difference.

The capacitance between leads/mic body might be small, but so is the capacitance of a capsule. It made the mic sound a little thinner when the leads were run together. Sounded more "full" when I redressed the leads.
 
Both of mine have their leads running through their own holes.

Is it uncommon for two identical mic builds to have a ~2db difference in output?
 
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