Measured VF14 characteristic

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granger.frederic said:
look in another 10 000$ mic, an ELECTROLYTIC decoupling cap on the backplate capsule: http://www.sdiy.org/oid/mics/SonyC800G.gif or

http://gyraf.dk/schematics/Sony_C800G_Schematic.gif

what all this pro mic designers are thinking !!!!They are really incompetent, aren't they misha ?

It's a bigger cap and therefore should have smaller effect on sound if I have understood anything.

And dear Fred: still that mean tone. Why? And why not discuss the C800G cap in the thread I just started?
 
I've read this thread on and off because you have some interesting thoughts.
I don't know all about what's been said between you guys but the tone is to me sometimes
a bit harsh, and I don't understand why?
I have an original U47 and a clone using an EF14, and another clone using an EF12.
The one using an EF12, I have three different tubes, and they all sound different.
My original Neumann (Tele badge, 2xxx serial nr, M7) and EF14 clone are without tube options.
Can I be of any help to you guys? I'm no tech guy, but I love microphones  :D

I've had several mic's serviced by Grosser and I've seen his name in this thread several times,
I'm very interested in his VF substitutes, and will probably buy his FET version in the near future,
What do you experts think of it??
Maybe I shouldn't bring up that question here, but I thought it's been mentioned here before,
so it's ok??
And yes, I have his approval since he serviced my U47 and PSU not long ago.

Best regards
Magnus
 
The VF14EF is the best subtitute for the U47  if you doesn't care about its Fet nature. The sound of VF14EF is closer to VF14M than any tube. If you have the original U47, then you may try this tube in comparisson with VF14 and to decide by yourself: is it good for you, or no. It is the best way to get the answer, IMHO. As far as I know, Andreas may sale this tube for owners of original U47. I, personally, like VF14EF sound.
 
Thanks for your answer.
If I may take this a bit further, has anyone of you compared the VF14 EF to the VF14 ER?

Thanks
Magnus
 
Gearslutz.com the guy from this forum made big test of Andreas Grosser substitutes. Start search as " Andreas Grosser" or VF14EF substitute and you will find topic with test and discussion.
 
misha,
are you working for Mr Grosser ?

We're in a DIY forum,
Mr Grosser has chosen to sell his tubes only for U47 owners.I doubt that each reader has the chance to have one...

I respect his work, and i'm sure that he's doing some wonderful products.

However, if you want to make someone's product promotion, please could you use the White market thread, or create a website dedicated to Mr Grosser.

Or if you have something new about VF14 measurements and substitution, let us know and we could debate between the few people who have a real U47, and the other majority which is building clones by themselves.

For those who put a hot bias on a 13CW4, i've asked other techs and they thinks that the longevity of the tube shouldn't be really affected.

 
Now please, guys - we're getting close to the edge of our MostImportantForumRule: No Personal Attacks

You two have a honest disagreement of ideas - present your side, and let all us other try to decide which has the best points, and what to learn from it.

I'm pretty sure there is no simple black&white answer here.

With respect,

Jakob Erland
LocalMod
 
granger.frederic said:
PIO are good caps when they are well built, in C1 they should produce more or less the same sound than a good film cap.
In my examples one C1 is very expensive tested PIO and C2 is usual standart MKT cap.  ;D
 
I guess I shouldn't have polluted this thread with my questions, I'm sorry!!
I've read that thread from "Slutz", thank you.
So if any of you have some interesting thoughts/opinions about the substitutes, you can PM me,
so we can keep a civil sharing of interesting knowledge here.

Kind regards
Magnus
 
Oh, it's not you fault, this thread was already polluted by various personal attacks : deleted and modified posts, "you're a liar"...etc etc

Once again, Mr Grosser is an excellent tech, but it's too bad that his substitutes are for genuine U47 only.

I've experimented a lot of tube in my U47n, and today i think that the 13CW4 with a bias at 0,65V is the best substitution i've tested.

I've tested EF14 (with my tweak and without), EF12 , UF14 ,parallel 6028, EF800, EF844S (rare tube), 7598, 6SJ7, 6072A (plate follower and CCDA ), EF42 and 13CW4.

for me, the 13CW4 is better, followed by EF14, then EF12.

13CW4 cuts through a mix (like EF14) and has the softness in the highs (like EF12)

the only issue is that it's hard to pick a 13CW4 usable in a U47.

Cheers
 
You can buy VF14er without being owner of Neumann U47. And, as far as I can see, you also already can buy VF14EF. http://www.voxorama.com/service/detail/andreas-grosser-vf14ef.html
 
Hey guys, I was really bussy with some rec. sessions and today I was shocked with dozen email nots about this topic... Wow, here is the real war going on about impotance of  5c C1 ;)
As Gyraf stated there is no B&W answer especially when its almost impossible to measure the influence of the C1 inside the U47. Only way is to measure it in dead silent enchoic room with long distance positioned source of sound :/  and then to change the capacitor and repeat the measurings. Besides that, humidity and temperature have to be the same... Also the temperature inside the microphone. Forgot something? ;)
But one thing is for sure. If the microphone works dirty withouth this part, then different cap material will act diferent. All that because capacitors loses can be diferent at high frequencies, also, the materials act diferent with changing the temperature, and so on.... My personal opinion (hope that I will not hurt enyone feelings) is that original Neumann's C1 (ceramic) works just right and if t's broken it have to be replaced with the same type. If you are building the clone than U have to experiment and it can last forever, same as this conversation ;)
 
Which Neumann U47  is "The U47"? I have got two U47s. In one mic I have polystirol (original c1), and in second one I had ceramic C1 (original) which I replaced with PIO. What is right for U47 polystirol or ceramic?  I think that there is no "the one pure original U47" today. We even have not got the capsules from 1950s in great condition. Its up to us to decide which sound we prefer. The main thing is to understand what exactly we are doing, when we  change the parts. That's why I continue to answer... 
 
bypass or decoupling capacitors have an impact on sound in theory.
i admit that, no problem.

but mostly when a transient curent demand occurs and in a quite big range (at least a few hundreds of mA),then it works like a device’s local energy storage.

in mic capsules and decoupling caps on them, we have some nA , not enough energy, for me (and probably Neumann techs), to impact the sound in the hearing frequency range, when you change the cap quality.
We're talking about 0,002% or something like that, and Moby has understood that it's virtually non measurable.
their utility is to filter and put the 0vAC reference for the backplate, that's why when C1 is out, the sound is so small and dirty:the capsule looses its 0VAC reference.

i'm sometime a bit sarcastic because , i hate talking during hours about non measurable things , and like Gyraf and Moby said there's no B&W answer, so we can't ASSURE that PIO or whatever C1 caps, HAVE and an big impact on the sound .I add that i'm becoming very suspicious when shootouts are coming to support his own thesis.

I assure that i have nothing against opposite opinions in general and with C1 in peculiar , and i think that even if the debate was sometimes very vigorous, it was never with an abusive language .

My intentions were pure : to focus on essentials, like the capsule , tube (this thread), output transformer ,head basket, coupling caps...all the parts that are 99,9% of the microphone sound .

If someone married wants to experiment with C1 , my last advice is to divorce before  ;)

I hope that this last post will bring back the peace

Cheers
Fred

 
o3misha said:
Which Neumann U47  is "The U47"? I have got two U47s. In one mic I have polystirol (original c1), and in second one I had ceramic C1 (original) which I replaced with PIO. What is right for U47 polystirol or ceramic?  I think that there is no "the one pure original U47" today. We even have not got the capsules from 1950s in great condition. Its up to us to decide which sound we prefer. The main thing is to understand what exactly we are doing, when we  change the parts. That's why I continue to answer...
Hi mate. Both of them are original. Neumann changed a lot of things during the years, capsule skin material, transformer lamination material, shape of the tx core, resistor types, cap materials, bla,bla... All of them sounds OK, more or less ;) I dont say that parts dont change the sound, of course they do! Here, we try to help people repair or to make a good clone of U47. So, lets's stick to geniune parts as much as possible. Unfortunatelly Vf14 is too expensive or unavailable so I think that's the biggest problem to deal with. Can we go back to topic subject? That's why I was experimenting with the nuvistor and shared the result here. Can we figure out some more good or maybe better substitutes? That will be so awesome :) (btw I hate this word;)
 
I'm working on a solid state substitute with germanium transistors.
i'll report as soon as possible if the results will be good sonically.(with measurements and schematic off course)
As i don't have a VF14m, i'll take the THD profile of the 13CW4 and EF14 for reference.
If someone could post the THD of VF14m ...

Solid state will resolves the voltage drop, and i can choose the temp inside the mic.
it resolves the cost
It resolves the operating lifetime as well...

i really like the sound of the germanium transistors in my overdrive/distortion guitar pedals (quite close to tube disto), but the major issue with that type of old transistor, is the noise and the thermal stability/drift...and the ultra high input impedance capability needed...
 
germanium transistors must run at low temperature if we don't want some noise.
a sometime important miller effect, is also limiting for a mic application...
wait and see ...
 
granger.frederic said:
germanium transistors must run at low temperature if we don't want some noise.
a sometime important miller effect, is also limiting for a mic application...
wait and see ...
I'm looking forward to it. BTw, I never heard Anrdeas fet version of Vf14 but I'm sure it sounds good.  I also wonder how he managed that fet crcuit?
 
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