Telefunken ELA M 251 Clone Tube Microphone Build Thread (D-Ela M 251E)

[Moby]

Is there anyone that could point me in the direction of how to wire the Haufe T14/1 (6 wires) to the the board/connector. Trying one out against my already installed AMI. From all accounts it looks as though two of the leads are connected on the secondary side its just hard to tell which? Red/blue/blue/red on secondary and green/green on primary.

I don't know if they make it exactly as the vintage original, but if yes you can use my wiring diagram. Meaning, blue wires are primary, red wires are sec. And for 200ohm you should connect green ones together.

 

[Carl Cress]

I don't know if they make it exactly as the vintage original, but if yes you can use my wiring diagram. Meaning, blue wires are primary, red wires are sec. And for 200ohm you should connect green ones together.

Thank you for the quick reply Moby.
So for todays modern purposes would you recommend connect green wires or leave disconnected? And/or how was the original wired?

 

[Moby]

Thank you for the quick reply Moby.
So for todays modern purposes would you recommend connect green wires or leave disconnected? And/or how was the original wired?

Hey, you cant leave it open because if you leave it open, secondary winding will not be active. So, you connect green-green for 200ohm and if you put in in parallel red-green it will be 50ohms. For the modern connection you should use 200ohms

 

[Carl Cress]

Hey, you cant leave it open because if you leave it open, secondary winding will not be active. So, you connect green-green for 200ohm and if you put in in parallel red-green it will be 50ohms. For the modern connection you should use 200ohms

Great! You've been a great help. Have a great weekend Moby!

 

[Purplenoise]

Is there anyone that could point me in the direction of how to wire the Haufe T14/1 (6 wires) to the the board/connector. Trying one out against my already installed AMI. From all accounts it looks as though two of the leads are connected on the secondary side its just hard to tell which? Red/blue/blue/red on secondary and green/green on primary.

Blue are the primaries.
Red secondaries
Green you connect together

edit. Sorry I see it’s been answered already

 

[Purplenoise]

I see the new Telefunken uses a 10000pf styrene cap. Is this replacing the 4800pf cap in the schematic? What is the effect of increasing the value of this cap?

 

[Tahoebrian5]

Can anyone comment on how much tube choice affects the tone on this mic? I finally have all my parts together except a tube, and gearing up to build it. Trying to decide if I should stick with 6072 or go with the 12a type as recommended by a tube supplier I spoke with.

 

[Purplenoise]

Can anyone comment on how much tube choice affects the tone on this mic? I finally have all my parts together except a tube, and gearing up to build it. Trying to decide if I should stick with 6072 or go with the 12a type as recommended by a tube supplier I spoke with.

A good nos 6072 (ge 5 star) is becoming scarce and expensive. The new production ones don’t sound as good as those.
In the 12at7/6201 case you have a a lot more options…tonaly and money wise. I have built one with 12at7 and sounds great. Currently I have a telefunken 12at7 in but depending on your capsule and aesthetic you might go for a darker or brighter tube.
You need a slight mod to bias the 12at7 properly, 47k resistor instead of 100k and then change the two 75k resistors in the psu to 33k to get proper B+.
When rolling 12at7s always check B+ because it can deviate up to 10v depending on tube.

 

[Tahoebrian5]

Thanks for the feedback. I think you have convinced me having options is key as if I spend $300 on a nice quality nos 6072 that will probably be the end of my testing in that department! So 12AT7 it is.

 

[Recording Engineer]

Is that how much they are now? It’s been a while since I last bought one for $150.

 

[Purplenoise]

Thanks for the feedback. I think you have convinced me having options is key as if I spend $300 on a nice quality nos 6072 that will probably be the end of my testing in that department! So 12AT7 it is.

David bock uses them in his 251s so you can’t go wrong I guess
This way you save for a better capsule which is far more important

 

[Purplenoise]

Is that how much they are now? It’s been a while since I last bought one for $150.

Yup…for a properly tested mic grade one it’s around $250/300

 

[Recording Engineer]

Hmmm… Close enough to Phaedrus prices to make it worth a try!

 

[Purplenoise]

Hmmm… Close enough to Phaedrus prices to make it worth a try!

I have a phaedrus ac701 in an m49 style mic. It sounds great but…it sounds more like a fet than a tube mic. To my ears at least ( not that I have a problem with that)

 

[Gus]

I have a phaedrus ac701 in an m49 style mic. It sounds great but…it sounds more like a fet than a tube mic. To my ears at least ( not that I have a problem with that)

Does the bottom sound "a little thin" or too "tight"?

I don't understand what people mean when they say something sounds more like a fet microphone than a tube microphone IN SOME CASES.

I have built a solid state microphone years ago that was thought to be a tube based one because of the external power supply

You need to do blind testing to make any statements about microphones IMO.

I think once someone has an idea of what the microphone circuit is they hear differently.

 

[Purplenoise]

Does the bottom sound "a little thin" or too "tight"?

I don't understand what people mean when they say something sounds more like a fet microphone than a tube microphone IN SOME CASES.

I have built a solid state microphone years ago that was thought to be a tube based one because of the external power supply

You need to do blind testing to make any statements about microphones IMO.

I think once someone has an idea of what the microphone circuit is they hear differently.

Maybe you are right but so far to me it seems that fet and tube mics react a little different on the transients. Fets feel more dynamic thus “dryer” to me and most tube mics have a slight compression effect that gives more “space”. Besides the tonal difference that was the most evident thing when I changed from 5840 to phaedrus in the m49…and also comparing mine to an original. The phaedrus brought my “clone” a lot closer to the original but the original rounded the transients more and sounded more even in that respect…of course I could be wrong but I think that’s because of the tube

 

[Moby]

Can anyone comment on how much tube choice affects the tone on this mic? I finally have all my parts together except a tube, and gearing up to build it. Trying to decide if I should stick with 6072 or go with the 12a type as recommended by a tube supplier I spoke with.

The main problem with the 12a tubes is the noise. Also, most of the 6072's are too noisy for the microphone application. If you can source the low noise "12a" you are good to go with it. But it's hard to find one. That's why people favorise the GE 6072 5*. They sound good and in the most cases they have acceptable noise.

 

[Tahoebrian5]

The main problem with the 12a tubes is the noise. Also, most of the 6072's are too noisy for the microphone application. If you can source the low noise "12a" you are good to go with it. But it's hard to find one. That's why people favorise the GE 6072 5*. They sound good and in the most cases they have acceptable noise.

Understood. The guy I talked to indicated he tests them all to make sure they are suitable for a mic. The 12A’s go for around $65 compared to $300 is fairly appealing. I just wanted to make sure it wasn’t going to change the character of the mic too much as I don’t want to go through all the trouble to build it and not have it sound like an Ela family mic.

On the other hand I can’t help wondering if I should go ahead and get a good NOS 6072 while it is still an option at all.

 

[Moby]

Understood. The guy I talked to indicated he tests them all to make sure they are suitable for a mic. The 12A’s go for around $65 compared to $300 is fairly appealing. I just wanted to make sure it wasn’t going to change the character of the mic too much as I don’t want to go through all the trouble to build it and not have it sound like an Ela family mic.

On the other hand I can’t help wondering if I should go ahead and get a good NOS 6072 while it is still an option at all.

I don't know if the guy can test them against the noise. But if he can, $65 is a great price for the low noise 12a. Fingers crossed!

 

[TLRT]

I don't know if the guy can test them against the noise. But if he can, $65 is a great price for the low noise 12a. Fingers crossed!

I can also do that. Btw better quality 12at7 versions have lower noise than GE6072's.