Neumann U67 Clone : D-U67 Tube Microphone Build Thread.

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So this is weird, but I just tested it again after putting it back together (I took it apart for the troubleshooting and breath test, etc.) and now it sounds fine again!! I wonder if some wire or something was out of place or hitting the side or something? But anyways, it sounds fine for the moment...

Still a killer mike!

Make sure it is not just a wire touching the tube grid point connection , that might could be it ,
easiest solution the better,

Best,
Dan,
 
JessJackson said:
so i finished my build, sounds great and just shot it out against vintage unmodified u67 here at paramount studios

Im using:

T67
Eric's 87 capsule with backplates tied together in cardioid
ero 1uf cap as seen above.
I'm at 208v b+ at full turn and 6.3 heater

Going back and forth on female singer my mic instantly is 5db hotter than the vintage u67
The top end is slightly more harsh/brittle and the bottom end is massive, too much lower mids in comparison to the u67 but was thinking it could be using the 1uf instead of a 0.5 over saturating the transformer possibly.

Other than that its very similar but I probably wouldn't use it until I can tune it to sound right without additional eq

I may throw a neumann k67 in there as i suspect thats the culprit for the slightly harsher tops.

cheers.

J
Did u get a chance to put that k67 in? If so how does it compsre to the vintage u67 now?  Im thinking of going all out with the neumann k67. 

Dan, thanks for this awesome project, ive wanted a u67 ever since the day I heard one and now its within reach.  How do the ami t67 and the ioaudio bv12 compare and which one do you recommend? Thanks again
 
mistasanshou said:
JessJackson said:
so i finished my build, sounds great and just shot it out against vintage unmodified u67 here at paramount studios

Im using:

T67
Eric's 87 capsule with backplates tied together in cardioid
ero 1uf cap as seen above.
I'm at 208v b+ at full turn and 6.3 heater

Going back and forth on female singer my mic instantly is 5db hotter than the vintage u67
The top end is slightly more harsh/brittle and the bottom end is massive, too much lower mids in comparison to the u67 but was thinking it could be using the 1uf instead of a 0.5 over saturating the transformer possibly.

Other than that its very similar but I probably wouldn't use it until I can tune it to sound right without additional eq

I may throw a neumann k67 in there as i suspect thats the culprit for the slightly harsher tops.

cheers.

J
Did u get a chance to put that k67 in? If so how does it compsre to the vintage u67 now?  Im thinking of going all out with the neumann k67. 

Dan, thanks for this awesome project, ive wanted a u67 ever since the day I heard one and now its within reach.  How do the ami t67 and the ioaudio bv12 compare and which one do you recommend? Thanks again

Nah I haven't had the chance yet… been too busy in the studio.. i'll do it this week. I did powder coat one side of the basket black though, lol

I would rock the k67 if I was you, there doesn't seem to be anyone able to match it and according to the greats, neumann senheiser still manufacture them to the highest quality.
 
JessJackson said:
mistasanshou said:
JessJackson said:
so i finished my build, sounds great and just shot it out against vintage unmodified u67 here at paramount studios

Im using:

T67
Eric's 87 capsule with backplates tied together in cardioid
ero 1uf cap as seen above.
I'm at 208v b+ at full turn and 6.3 heater

Going back and forth on female singer my mic instantly is 5db hotter than the vintage u67
The top end is slightly more harsh/brittle and the bottom end is massive, too much lower mids in comparison to the u67 but was thinking it could be using the 1uf instead of a 0.5 over saturating the transformer possibly.

Other than that its very similar but I probably wouldn't use it until I can tune it to sound right without additional eq

I may throw a neumann k67 in there as i suspect thats the culprit for the slightly harsher tops.

cheers.

J
Did u get a chance to put that k67 in? If so how does it compsre to the vintage u67 now?  Im thinking of going all out with the neumann k67. 

Dan, thanks for this awesome project, ive wanted a u67 ever since the day I heard one and now its within reach.  How do the ami t67 and the ioaudio bv12 compare and which one do you recommend? Thanks again

Nah I haven't had the chance yet… been too busy in the studio.. i'll do it this week. I did powder coat one side of the basket black though, lol

I would rock the k67 if I was you, there doesn't seem to be anyone able to match it and according to the greats, neumann senheiser still manufacture them to the highest quality.
hey man, any time for an update yet?
 
I'm excited because I finally got my beesknees K6 capsule back...Now to replace the cheapie Chinese capsule with it! I'll let you guys know how it ends up sounding etc, I'm excited!!

Mike
 
Melodeath00 said:
Me as well! Update us ASAP. Did you like the mic before even with the cheap capsule?
Yes! As you know psychoacoustics can play a huge role in our experience/perception of auditory phenomena; ie if I think it's a crappy capsule I'll hear a crappy sound, but it had a nice full smooth and beefy sound with a hint of that special magic we look for in great mics. I'll post back after installing the new capsule, although it might be a little while since I may have to rework PSU voltages for the new capsule (I probably need to swap some resistors).

Thanks,

Mike
 
Phrazemaster said:
Melodeath00 said:
Me as well! Update us ASAP. Did you like the mic before even with the cheap capsule?
Yes! As you know psychoacoustics can play a huge role in our experience/perception of auditory phenomena; ie if I think it's a crappy capsule I'll hear a crappy sound, but it had a nice full smooth and beefy sound with a hint of that special magic we look for in great mics. I'll post back after installing the new capsule, although it might be a little while since I may have to rework PSU voltages for the new capsule (I probably need to swap some resistors).

Thanks,

Mike

thats great news , but you would not have to change any voltage for a diefferent capsule , could you explain a bit ,
Best,
daN,
 
I was being vague sorry - of course not changing voltage for the capsule. What I meant was, I want to install the new capsule, and then check to see where voltages are since at the moment I'm getting barely in-range voltages for B+ and H. I likely need to change resistor values as per our previous discussion, which is likely due to the particular tube I have or other unknown factors to why my voltages are not in the center of the pot range. I didn't know if the new capsule would have any effect on the existing voltages - my ignorance but I thought I would change the capsule first and then check the voltages.

I'll post back, and thanks Dan.

Mike
 
OK, got the new capsule installed! As usual, there was a lot more to it than "drag and drop"! I had to do a lot of drilling/prepping the new capsule holder arrangement since the K6 capsule has its own stand and I wanted to use it. Sigh. As expected, anything custom takes more time!

So I'm posting links to clips, one using a Chinese capsule I got from a Chunger build, and the second the BeesKneez K6 capsule. It's yours truly singing, so please don't kill the messenger!

I was holding the mic (iknow!) about 4-6" from my mouth. Different days - actually weeks apart. Some of the difference is simply my voice was different between the two takes! This is not scientific at all! Only processing whatsoever was to use the "normalize" effect on each to within 0.5db of 0.

Thoughts?

Mike

Chinese Capsule: http://pctrainingexperts.com/portals/0/audio/chinese.mp3
Beeskneez K6: http://pctrainingexperts.com/portals/0/audio/k67-2.mp3
 
Thanks for the samples, Mike. We need more brave guys like you!

The different takes do make it a bit tricky. I hear somewhat smoother esses on the second as well as more body down below, but e.g. that could also be caused by just a hair closer proximity.

Now that the K6 is in there, could you do some samples with you closer on the mic? The U67 was designed to be well suited for close miking (pun intended), that is, in case of less forte singing of course (or talking for that matter). But you may need a popfilter for that (if you don't use one already).


Henk
 
Thanks for the feedback Henk. In both cases I had the mic "about" the same distance - I was holding it in my hand since at my house I don't have a studio stand. I was probably about 4-6" from the mic; almost eating it, so although I could get even closer, this was a lot of proximity. While I obviously will not be able to post future clips of the mic with the Chinese capsule, I'll see what I can do about getting some samples from my studio proper.

I feel the new capsule is much clearer and yet also retains warmth, which sometimes is mutually exclusive! Being anal, funny how the word anal is part of anal-ysis, I concur that better matching of the clips and proper setup would have been much preferred. I was just delighted to note that I even had saved the original takes, so thought to just post something quick.

Hope this is a little helpful anyhow, and thanks guys for the terrific community and camaraderie. As pathetic as it may sound, you guys are like my buddies and I enjoy interacting with you all and building cool stuff.

Warm regards,

Mike
 
http://store.studio939.com/product/35mm-k67-style-capsule

Sorry if I have missed but has anyone tried these K67 cheap capsules ..... nice price.
 
gary o said:
http://store.studio939.com/product/35mm-k67-style-capsule

Sorry if I have missed but has anyone tried these K67 cheap capsules ..... nice price.
Yes I tried this capsule; it was what I had installed before I got the Sneesby capsule.

I thought overall it was a fairly nice capsule; maybe a little "softer" sounding but still useable. With the world-class circuit of the D67 behind it, I think it helps. I'm glad to have the higher end one, however, as it seems fuller, to have more "presence."

hth,

Mike
 
I just knocked up an experimental version of U67 circuit .... I dont have correct transformer & capsule at moment so i used maxes BV08 & a k47 capsules... I left out C3 C17 R18 r19 & R20 for Im getting audio but fairly low level lower than U87 circuit ...... does that sound right....... for now Im using two power supplies one for B+ & one for heater but reversed 6.3Volt is that ok way to power it.....just wanting to learn about the circuit for now..... the sound I get from the mic is pretty good little bit white noise mush tho ...... I was just experimenting with the much simpler circuit  of the Oliver Archut UM75/92/92.1 with same transformer & capsule good sound more level less noise...... not expecting too much as Im using wrong transformer but Im wondering where the noise is coming from.
 
Quick update to my last post...... if I turn off the 6.3 heater voltage the white noise goes completly mis still passes audio for a few seconds as heater cools down .....the heater PSU doest cause any noise with mic I made that are powered the usual way..... I need to understand more about the way the U67 is powered ...... interesting .....

Merry christmas
 
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