Enchilada's Mic Builds - U47 /U47FET Comparison!!!

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So what's your guess/preference?

No guess anymore since I saw the results. But I don't want to spoil it for others.
What I can say is that the one with the CT12 capsule is my favorite, which is no real surprise.  :)
The one with the RK47 is middier obviously and a little harsh on this particular female vocal.
The RK12 suits here better IMO and has plenty air. It's just not as smooth as the Campbell.

OK, now tell us you deliberately provided the wrong key.  ;D


Disclaimer: I did not listen very closely or with headphones and such, yet. First impression rather than critical, detailed listening.
 
Thanks mate!

Yeah I'm really impressed with the three mics based on this initial test. I definitely agree though that for this song and for Lauren's voice the RK47 capsule isn't a good fit.

I've now gotten the U47 clone going so I'll have to head back out there soon for another shootout! As I was soldering today, I stupidly left the 3Mohm resistor on my work bench  :-[. Now it's sounding much, much better. It takes it a very long time to settle down when changing patterns though. Also sounds VERY mid forward but not anywhere near as much as the 5693 tube U47 inspired mic I built a while back.


Now, as promised, here's my beloved new BeesNeez M7 capsule! (I uploaded this one with a higher res so you can see it better)

DSC_0011.jpg
 
Thanks for posting this.
I thought there was a slight difference between the C12 w CT12 and the Royer w/ RK12.  I thought the CT12 was little more real on key parts of the vocal. (was this the same performance or was it recorded three times?)
Now I have to save my money for one of Tim's capsules. I have a Royer (w/ beyer tx and GBC12) and a C12 (460 w/ GEtube, cw2480, GBC12) and they sound an awful lot alike.
I thought the 47 was really weak.
 
dmp said:
(was this the same performance or was it recorded three times?)

All three mics were used on the one vocal take.

dmp said:
I thought the 47 was really weak.

I think the problem with the 47 in this circuit is that the circuit was originally designed to tame the harsh 67 style capsule of the MXL 2001. Seeing as the 47 capsule rolls of the highs I don't think that's why it doesn't sound great in this circuit. I may be wrong, it's just my assumption. So far I've tried the 47 in the Royer and G7 and I don't like either. I have a pair of studio projects c1 mics, I've heard it sounds good in those so I might give it a go. I would really like to build a couple of microphones with my pair that I have though.

dmp said:
I have a Royer (w/ beyer tx and GBC12) and a C12 (460 w/ GEtube, cw2480, GBC12) and they sound an awful lot alike.

That surprises me because I've previously used the RK12 in a Royer, G7 and C12 circuit and they all seemed to have their own flavour. I much prefer the Royer though for the RK12.
 
Wow! Tims capsule is by far the best in my opinion, Especialy on that vocal track. The rk47 sunded harsh and the other chinese capsule wasnt as bad but still a bit to harsh for me. That being said all mics sound pretty darn good, very nice job. And I was suprised to see a 23mm target on that beez neez m7 capsule. The originel m7 has a 25mm target and goes almost to the edge, cait wait to hear it!

Eric
 
Enchilada said:
Here's a little shootout. Unfortunately, the U47 clone is not yet ready so it will not be competing this time around :-(.

Let's proceed. We have one C12 circuit with a CT12 capsule and two Royer circuits with RK12 and RK47 capsules. I have listed the mics in alphabetical order so as not to give anything away although I think it's fairly easy to tell which mic is which.

http://soundcloud.com/fat-wombat/sets/lauren-carlson-teenage-dream

This will be a semi-blind test because I've attached which mic was which in a text file if you want to know. Have a guess first though  ;).
I liked clip number two the best. Less sibilance, and harshness, but it still has a lot of clarity in the top end. Where did you possition the mics? Thanks for sharing.
 
I'm with the others. The 47 sounded harsh to me too on her voice. the two 12 clones were pretty close, the TC a bit "fuller" "creamier" (?) to my ears, but not much. Although the comparison isn't quite fair as two different circuits. That said, I like the Royer with the 12 style capsule! Nice work!!!!

 
Three microphones with one take is not a good test IMO.
Proximity effect and the resulting EQ from different distances and angles make a big difference

You really need to control every thing with a test
Something to try
using a recording set a microphone a measured distance from a fixed repeatable sound source something like a small speaker record the same recording at the same level at measured different distances make sure the capsule is at same spot X,Y,and Z in reference to the speaker make sure nothing else changes in the room to change reflections.
Then do the same with the other microphones
Yes this has issues as well it does not test pop sensitivity and....
 
excuse me if this was said, but i was wondering about the placement of the 3 mics also. I'd bet the #2 clip was the center mic? can that be verified or debunked?

thanx
cool thread
 
The mics were placed approx 50cm from the singer. Although mic 2 was technically in the centre, it was also placed off-axis (above the singer) by the same amount as the other two so none of the three were directly in line. All three mics have reasonably small headbaskets so I wouldn't say there would be a huge difference with the singer at 50cm. At that distance I doubt there would be much as far as proximity effect either.
 
This may play a part. At half a meter distance you lose some highs and lows. The somewhat scooped characteristic or smiley curve of the CK12 type capsules will compensate and thus have some advantage in this case. The K47 type favors the midrange more which only adds to the relatively strong midrange caused by distance.

But regardless, I'd say it's not unusual for female vocals, especially of this kind, to sound better through a CK12 than a K47.
I'd really like to hear an "intimate" (read: closer) male vocal through those three mikes.
And yes, in that case (close proximity), consecutive takes might work better. This will enable the vocalist to really be "on" the mike and it will allow him to find the sweet spot for each. The 47 may very well surprise us then.
 
Probably the best thing to do is ignore the RK47 at this point in time and focus more on the CT12 vs RK12. I'll be testing the RK47 against my U47 inspired mic soon which will give a closer comparison. I've removed the RK47 from Sound Cloud.

I'll use a male voice for the 47. I agree, in my experience I prefer females with the 12 style and male vocalists with the 47 style. I'm not saying with males I prefer the 47 over the 12, it really depends on the source.
 
I've removed the RK47 from Sound Cloud.

That's a pity. I thought it was quite educational to have all three there. And if the 47 falls short of the others it doesn't mean it's bad.
(BTW, I've added to my earlier post.)
 
**removed**

The ideal methodology to test microphones is probably something that could be discussed in a new thread and not here.
 
I'm not saying with males I prefer the 47 over the 12, it really depends on the source.
I agree completely.

Oh, and I prefer real humans over speakers, for this kind of thing, too.
Technical tests (pink noise and such) are another matter.
 
There seems to be something special about Tims capsule, I've order 2 of them a while back, i hope they are as good as they seem to be in all these shootouts and comparisons. I'm anxiously awaiting their arrival.
 
micaddict said:
I've removed the RK47 from Sound Cloud.

That's a pity. I thought it was quite educational to have all three there. And if the 47 falls short of the others it doesn't mean it's bad.
(BTW, I've added to my earlier post.)

Yes. It was a nice snapshot comparison of Royers with different capsules.
 
I've been trying a few different tubes this week. Tried my EF14 and was not impressed, sounded quite thin and scratchy. I also tried a few EF800 tubes and they sounded similar but with even less low end. I then tried a couple of Mullard EF80 tubes and surprise, surprise... the EF80 that I got from Oliver over at AMI is easily the best sounding tube I have in this circuit. He must have hand selected it for me :p

I also tried a 408a (6028) following the MK47 schematic i.e. taking the heater from the B+ but for some reason when it was all plugged in the B+ measured at only 9V  :eek:

I might try the 408a again in a different mic and see if I can get it going. Next time I might try running it with a dedicated 20V heater for simplicity.

Anyway, I'll record a comparison between this U47 inspired mic with the EF80 tube and my Royer with the RK47 capsule as they are kind of similar sounding. I think it'll be interesting to see how they sound right up close.

Stay tuned...
 
Ohm's law - the heater draws much more power from B+ (~50mA) than the anode(~0,55mA) so your psu must be able to supply 105v @ 50ma!

best,
max
 
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