Re: Telefunken ELA M 251 Clone Tube Microphone Build Thread (D-Ela M 251E)
« Reply #720 on: December 14, 2020, 01:56:42 PM »
As I am still waiting for the haufe t14 I used a cinemag for now just to test the mic. Changing the resistors to carbon film and the grid 30M to an old claro wirewound changes the sound significantly. Smoother and a touch dirtier but a lot closer to the vintage originals.
This time I prefer the tantalum 22uf that comes in the BOM...a more organic sound. I tried a nos axial Siemens tantalum and a sprague wet tantalum and although it sounded big and great it lacked a little of the midrange “reed-ness”.
The output cap is a 1uf 150v wet tantalum.
« Last Edit: December 14, 2020, 02:05:22 PM by Purplenoise »


tonycamp

Re: Telefunken ELA M 251 Clone Tube Microphone Build Thread (D-Ela M 251E)
« Reply #721 on: December 22, 2020, 05:38:58 PM »
Hi guys, I still have NOT wired up the multi pin cable to run from the PSU to the mic, but can anyone tell me if getting 150vdc at the B+ terminal 1 on PSU board is correct? I’m figuring it must drop at the back of the mic jack but 30vdc seems a lot to me, I wanted to ask to be sure, thanx for sharing any info👍

Re: Telefunken ELA M 251 Clone Tube Microphone Build Thread (D-Ela M 251E)
« Reply #722 on: December 22, 2020, 07:55:48 PM »
Hi guys, I still have NOT wired up the multi pin cable to run from the PSU to the mic, but can anyone tell me if getting 150vdc at the B+ terminal 1 on PSU board is correct? I’m figuring it must drop at the back of the mic jack but 30vdc seems a lot to me, I wanted to ask to be sure, thanx for sharing any info👍
You’ll have to have the mic connected to get an accurate reading or use a resistor at the 7 pin xlr ( I believe that resistor is included in the bom...180k 2w if I am not mistaken). Then you just adjust the trimmer for B+ for 110/120v ( depending on capsule) The procedure is explained in the thread somewhere.

tonycamp

Re: Telefunken ELA M 251 Clone Tube Microphone Build Thread (D-Ela M 251E)
« Reply #723 on: December 22, 2020, 10:45:26 PM »
Thanx man! It’s been so long since I started the project that I completely forgot about the 80k test load, I started reading into the thread but had to do some chores, when I saw your post I checked my project container and saw the pic below👍 Everything measures out perfect!
Thanx again 
You’ll have to have the mic connected to get an accurate reading or use a resistor at the 7 pin xlr ( I believe that resistor is included in the bom...180k 2w if I am not mistaken). Then you just adjust the trimmer for B+ for 110/120v ( depending on capsule) The procedure is explained in the thread somewhere.

Re: Telefunken ELA M 251 Clone Tube Microphone Build Thread (D-Ela M 251E)
« Reply #724 on: December 24, 2020, 02:31:19 PM »
A little update for those interested.
Tried a Black Gate standard for the cathode bypass ( 22uf) cap. I found a 47uf 16v and it sounds the best out of all the caps I tried in this position. Not that far off the Elna silmic but more detailed and dynamic. The silmic sounds a little veiled compared to the black gate. Since I am using the Tim Campbell capsule I uped the 100pf high cut cap to 250pf and it sounds fantastic with a great deal of 3D sense. I have those 2 caps in sockets so I can just swap in and out without desoldering.
Still waiting for the Haufe t14

duantro

Re: Telefunken ELA M 251 Clone Tube Microphone Build Thread (D-Ela M 251E)
« Reply #725 on: December 31, 2020, 11:45:14 AM »
Check for shorts along your B+ path in the mic/ cable

Re: Telefunken ELA M 251 Clone Tube Microphone Build Thread (D-Ela M 251E)
« Reply #726 on: March 05, 2021, 11:49:30 AM »
So the build is complete. Installed a haufe t14 and it sounds great...mix ready almost.
After many component changes I ended up with:
-Tim Campbell capsule
-haufe t14
-black gate std cathode cap 47uf
-wet tantalum 1uf 150v
-nos ge6072 (60s)
-wirewound clarostat 29.7M grid resistor
-carbon film resistors
-250/300pf styrene high cut cap

I am really happy with this...for now haha

Re: Telefunken ELA M 251 Clone Tube Microphone Build Thread (D-Ela M 251E)
« Reply #727 on: March 23, 2021, 12:12:05 PM »
Hello everyone :) I'm having a weird problem, when mic is connected B+ doesn't drop at all. I noticed that there is 0V on R3 and R6. I just made a new Gotham cable and checked the connectivity between the pins on both sides and everything there looks right. No shorts between pins either. Any suggestions? :)

Frank00

Re: Telefunken ELA M 251 Clone Tube Microphone Build Thread (D-Ela M 251E)
« Reply #728 on: April 06, 2021, 06:28:59 AM »
Hi guys,

Since the relay in the BOM (Panasonic DS2Y-S-DC6V) is out of stock at Mouser (at least here in Italy) and will be soon discontinued, I tried to find a replacement.

Here is the one I found:
https://www.mouser.it/ProductDetail/653-G6A-274P-DC6

From the specs, it looks like an exact replacement (even the housing dimensions) with the added bonus of having a 1Gohm insulation resistance (as opposed to 100Mohm of the BOM relay, which I know has been a topic of discussion before).

Do you think I could use it instead of the original one? I'd love if someone more experienced than me could share his opinion.

Thanks,
Francesco

Re: Telefunken ELA M 251 Clone Tube Microphone Build Thread (D-Ela M 251E)
« Reply #729 on: April 15, 2021, 02:39:06 PM »
So the build is complete. Installed a haufe t14 and it sounds great...mix ready almost.
After many component changes I ended up with:
-Tim Campbell capsule
-haufe t14
-black gate std cathode cap 47uf
-wet tantalum 1uf 150v
-nos ge6072 (60s)
-wirewound clarostat 29.7M grid resistor
-carbon film resistors
-250/300pf styrene high cut cap

I am really happy with this...for now haha

Great work, man !
Mine is working since 2 years with no issues. Stock parts so far, but I really like. Just stared to swop output caps. MKP 3UF, CDE MPW 3,3uf and end up with a Russian PIO 3,3 uf. Wet tantalum in 1,75uf are on their way. High opener !
Perhaps I try your 30m resistor upgrade 😅. Experimented a bit with it at the beginning. Tried to move it up to 100m but I prefer the 30m there. The influences to sound was huge, so I may try your choice.

Setup:
- Tim Campell CT12
- AMI T14 (spare Haufe at Hand)
- K42-11 3,3UF 125V
- NOS 50s Honeywell 6072


Re: Telefunken ELA M 251 Clone Tube Microphone Build Thread (D-Ela M 251E)
« Reply #730 on: April 15, 2021, 06:01:37 PM »
Great work, man !
Mine is working since 2 years with no issues. Stock parts so far, but I really like. Just stared to swop output caps. MKP 3UF, CDE MPW 3,3uf and end up with a Russian PIO 3,3 uf. Wet tantalum in 1,75uf are on their way. High opener !
Perhaps I try your 30m resistor upgrade 😅. Experimented a bit with it at the beginning. Tried to move it up to 100m but I prefer the 30m there. The influences to sound was huge, so I may try your choice.

Setup:
- Tim Campell CT12
- AMI T14 (spare Haufe at Hand)
- K42-11 3,3UF 125V
- NOS 50s Honeywell 6072
Nice...I tried PIO and Mp caps in this build and didn’t like them very much. The high end was kinda “glassy” with the Tim Campbell capsule. I much prefer wet tantalum...smooths the high end nicely. Also a wet tantalum cathode cap sounds quite nice too.
The haufe is a little lighter on the low end so you might wanna change the cathode cap to 47 or 100uf to compensate if you use it.