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

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Phrazemaster said:
Question - the Bv11 xformers - will they lack bass extension/low end with a 5840 tube? I'm a little bummed I already ordered a max bv11 but a post said that Oliver has an AMI xformer BV11R that is supposed to be better suited for a 5840 tube...

So I'm wondering if a historic BV11 will be a problem or cause an anemic microphone bass-wise?

Thanks all,

Mike

I wouldn't worry about it, Mike. Dany's own prototype with 5840 was as far from anemic as you could imagine, "even" with the T49 tranny.
I would go for M49b rather than M49c, though.

Henk
 
Henk and Dan, much appreciated!

I was trolling the 'net to find more info on b vs c, and it seems to be the concensus agrees with you Henk. From what I read the c version, which has the advantage of a lower noise floor, is somewhat "softer" or perhaps not as present or aggressive (?) as b version. Please don't take this as fact; I have not listened to either version.

One post I read noted that the b version is much more dependent on the individual tube, showing its character and flaws, and the c version kind of evens all of that out. Subjective vague words to try to describe an auditory experience, but alas that's what I have.

In any case, I had already decided to build the b version. And now that riggler is probably doing a round 3, it looks like I'll be able to join the party! But dang, this stuff adds UP! Just ordered a nice wooden box for it, from vintagemicrophone.com.

Thanks again Dan and Henk!

Mike
 
Phrazemaster said:
Henk and Dan, much appreciated!

I was trolling the 'net to find more info on b vs c, and it seems to be the concensus agrees with you Henk. From what I read the c version, which has the advantage of a lower noise floor, is somewhat "softer" or perhaps not as present or aggressive (?) as b version. Please don't take this as fact; I have not listened to either version.

One post I read noted that the b version is much more dependent on the individual tube, showing its character and flaws, and the c version kind of evens all of that out. Subjective vague words to try to describe an auditory experience, but alas that's what I have.

In any case, I had already decided to build the b version. And now that riggler is probably doing a round 3, it looks like I'll be able to join the party! But dang, this stuff adds UP! Just ordered a nice wooden box for it, from vintagemicrophone.com.

Thanks again Dan and Henk!

Mike

Dont worry i included both version in the pcb kit just to make it harder to choose  ;)

Best,
Dan,
 
poctop said:
Phrazemaster said:
Henk and Dan, much appreciated!

I was trolling the 'net to find more info on b vs c, and it seems to be the concensus agrees with you Henk. From what I read the c version, which has the advantage of a lower noise floor, is somewhat "softer" or perhaps not as present or aggressive (?) as b version. Please don't take this as fact; I have not listened to either version.

One post I read noted that the b version is much more dependent on the individual tube, showing its character and flaws, and the c version kind of evens all of that out. Subjective vague words to try to describe an auditory experience, but alas that's what I have.

In any case, I had already decided to build the b version. And now that riggler is probably doing a round 3, it looks like I'll be able to join the party! But dang, this stuff adds UP! Just ordered a nice wooden box for it, from vintagemicrophone.com.

Thanks again Dan and Henk!

Mike

Dont worry i included both version in the pcb kit just to make it harder to choose  ;)

Best,
Dan,
You're not a brat or anything.  :p
 
Heya folks,

A couple questions about as I ponder jumping into this build:


#1 in looking at the photos of the build, crossing the leads from the tube to the PCB seems to make shorting likely. Is there a reason not to use heat shrink on those leads?

#2 Is there a specific case that's ideal for the PSU? (or did I miss that in the BOM lists somewhere?) EDIT: Fount it!

thanks!

AJ
 
ajemutt said:
Heya folks,

A couple questions about as I ponder jumping into this build:


#1 in looking at the photos of the build, crossing the leads from the tube to the PCB seems to make shorting likely. Is there a reason not to use heat shrink on those leads?

#2 Is there a specific case that's ideal for the PSU? (or did I miss that in the BOM lists somewhere?) EDIT: Fount it!

thanks!

AJ

#1 in looking at the photos of the build, crossing the leads from the tube to the PCB seems to make shorting likely. Is there a reason not to use heat shrink on those leads?

I personnaly dont use shrink warp on this build on the the tube leads as once they are soldered in they are very stiff and very unlikely to move or short.

Best,
Dan,
 
#1 in looking at the photos of the build, crossing the leads from the tube to the PCB seems to make shorting likely. Is there a reason not to use heat shrink on those leads?

I'd suggest using tubing on all the leads except the grid.
Leaving the grid open allows for easy cleaning, but with the other leads covered, you prevent a short. Having the high voltage wire exposed in particular would make me nervous.
I prefer teflon tubing over heat shrink.
http://www.redco.com/Redco-TT250.html
 
I got some Sommer Cable Octave Tube microphone cable. Its got 5 x 0,14mm2 (AWG26) and 2 x 0,5mm2 (AWG21).

Would you use the two thicker cables for pin 5 and 3?

What about the cable shield? I use a Binder connector at one end and an 7 pin XLR at the other.

Sorry for my noobish question...
 
Use thicker wire for the heater and ground (4 & 7). The heater has the highest current, requiring the higher gauge wire.
If there is a twisted pair in the remaining 5 wires, use them for the audio (1 & 2)
I think the cable shield should be attached to the metal of the PSU connector only, but Poctop should verify that.
 
Hi Guys,

I'm looking to buy some Galaxy Maggiorato cases for the PS for this project. Can anyone comment how deep the cases will need to be to fit everything?

The ones to choose between are:

2u x 230mm wide x 170 mm deep or
2u x 230mm wide x 230 mm deep

There is not too much difference in the price, but there may be a bit of price difference in shipping cost etc

Cheers,

Matt
 
Woot said:
Hi Guys,

I'm looking to buy some Galaxy Maggiorato cases for the PS for this project. Can anyone comment how deep the cases will need to be to fit everything?

The ones to choose between are:

2u x 230mm wide x 170 mm deep or
2u x 230mm wide x 230 mm deep

There is not too much difference in the price, but there may be a bit of price difference in shipping cost etc

Cheers,

Matt

I have been able to mount everything in the fantastic Dan's (dandeurloo) psu case they look very nice but i had to mount the choke on the side with countersunk screw on the face of the psu, for IMHO for 6 cm deeper i would go for it so you dont come short on space and it is probably easier to work with.

Best,
DAn,
 
Is anything changed in the PCB changed to compensate for use of the 5840 versus the AC701? Also, any insight into the 5703? I've seen that used in M49 tributes, as well as the 5744. Would any components need to be altered?

I've heard the EC1000 is noisy/finnicky, but there's also the Russian 6S6B and the 5719.
 
Melodeath00 said:
Is anything changed in the PCB changed to compensate for use of the 5840 versus the AC701? Also, any insight into the 5703? I've seen that used in M49 tributes, as well as the 5744. Would any components need to be altered?

I've heard the EC1000 is noisy/finnicky, but there's also the Russian 6S6B and the 5719.
I was curious about this too...bump Dany? :)
 
Phrazemaster said:
Melodeath00 said:
Is anything changed in the PCB changed to compensate for use of the 5840 versus the AC701? Also, any insight into the 5703? I've seen that used in M49 tributes, as well as the 5744. Would any components need to be altered?

I've heard the EC1000 is noisy/finnicky, but there's also the Russian 6S6B and the 5719.
I was curious about this too...bump Dany? :)

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,


 
poctop said:
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...

You mean 100uF?
 

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