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Logic behind tube vs regular mic sound difference?
Old 1 day ago | Show parent
  #691
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🎧 5 years
Quote:
Originally Posted by DougS ➡️
The thread has clearly covered a lot since then as its 15 times larger.


Normally it means it didn't stray far from the circles the tether only allows..
Old 1 day ago | Show parent
  #692
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Tomás Mulcahy's Avatar
 
🎧 15 years
Quote:
Originally Posted by nat8808 ➡️
As I see it, there are many conversations going on at once in a thread - everyone can skip the posts that don't interest them anyway.
Agreed. It's hard to follow. High SNR
Old 1 day ago | Show parent
  #693
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MandoBastardo's Avatar
 
🎧 10 years
Quote:
Originally Posted by Tomás Mulcahy ➡️
Agreed. It's hard to follow. High SNR
As I've said before...

We come to GS for the signal, but we stay for the noise.
Old 1 day ago | Show parent
  #694
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64gtoboy's Avatar
Quote:
Originally Posted by themiracle ➡️
The answer to the riddle posed in the original post is contained in the question.

There is no meaningful difference between "tube" mics and "regular" mics that can be so broadly generalized.

Tube mics do not sound warmer. Fet mics do not sound 'colder' or whatever.

Every microphone sounds different. The primary difference is always the capsule, but the entire device's design and construction must always be taken into account. No two mics sound the same, even mics of the same exact design will often capture the same source from the same position, a little differently, which is why some manufacturers offer additional paid services to "match" pairs.

If you keep everything else the same, changing only the valve circuit for a fet circuit, (such as comparing a u67 with an 87, generally speaking), you can start to identify differences between those two circuits.. such as the gentler progression into distortion you might experience overdriving the mic's amp circuit on the valve side..
but that's where the generalization ends. This idea that tube mics have a sound is a terrible red herring for those starting mic collections.


..but I'm sure you guys have had some very interesting discussion over the ensuing 23 pages
It just so happens that everything you have said is correct and has been restated many times over the previous 23 pages. Welcome to the circus!
Old 1 day ago | Show parent
  #695
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DougS's Avatar
 
🎧 5 years
Quote:
Originally Posted by nat8808 ➡️
Yep, choose with your ears not your imagination.
Agreed.
Old 1 day ago
  #696
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Nor with preconceptions or cognitive bias ...
Old 1 day ago | Show parent
  #697
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DougS's Avatar
 
🎧 5 years
Quote:
Originally Posted by TobyB ➡️
Nor with preconceptions or cognitive bias ...
Agreed in principal. But how?

As audio engineers we make many decisions (maybe thousands a day) with our ears. How do we know when preconceptions or cognitive bias is leading us astray? Impossible to double-blind test everything.
Old 1 day ago
  #698
Gear Maniac
 
I have a maybe stupid question. I was under the impression that Neumann moved to the 87 from the 67 because of certain advantages with using FETs instead of valves/tubes. I realize the 47 was "replaced" with the 67 due to unavailability of the specific tube. But why did they move toward the FET and not keep a tube mic in their lineup until the M149?
Did engineers in the 60s and 70s feel the 87 was just as good as the former tube mics they replaced?
Old 1 day ago | Show parent
  #699
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Tomás Mulcahy's Avatar
 
🎧 15 years
Quote:
Originally Posted by DougS ➡️
Agreed in principal. But how?

As audio engineers we make many decisions (maybe thousands a day) with our ears. How do we know when preconceptions or cognitive bias is leading us astray? Impossible to double-blind test everything.
Nope. There are two ways:
1. If it’s on audio test kitchen, you can..
2. Frequency response on several exes; transient response; distortion graph. Double blind is only one methodology, these are others.
Therefore it’s not impossible.
Old 1 day ago | Show parent
  #700
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haysonics's Avatar
 
🎧 5 years
Quote:
Originally Posted by Rob 28 ➡️
I have a maybe stupid question. I was under the impression that Neumann moved to the 87 from the 67 because of certain advantages with using FETs instead of valves/tubes. I realize the 47 was "replaced" with the 67 due to unavailability of the specific tube. But why did they move toward the FET and not keep a tube mic in their lineup until the M149?
Did engineers in the 60s and 70s feel the 87 was just as good as the former tube mics they replaced?
That's a great question !

On another forum Klaus Heyne stated that the reason for the move was cost because Neumann found the manufacturing quality of EF86s dropped off and they were discarding about 70% of tubes.

While that sounds believable and may be the case I wonder if it may have also been due to a change in the market. Neumann's published U67 frequency response graph shows a relatively flat microphone (taking into account they allow a +/- 4dB variance due to capsule manufacture). I have read accounts of studios modding their U67s to give an upper mid-range boost. I can understand this considering the positive reception for the brighter CK-12 capsule that AKG started producing at the end of 1959. The 1960s C12 (and ELAM 251) had that brighter capsule and IMO the majority of favorable comments about the C12 refer to that period (including the C12A with its nuvista tube). I believe the U87 was Neumann's competing product and it's success led to Neumann retiring the U67.

And of course there is also the cost of producing the tube power supply. The u87 could run off phantom power and it had a battery compartment. It was the future. It wouldn't be long before Neumann started questioning the need to have transformers in mics. Neumann's progressive thinking has been a majour factor in their success.

That's not to say everyone was happy with a brighter successor to the U67. The U89, with its relatively even frequency response, went someway towards filling the gap left by the retirement of the U67 (though of course it didn't have a tube or transformer).
Old 1 day ago | Show parent
  #701
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s wave's Avatar
Could it be SPL?
Old 22 hours ago | Show parent
  #702
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Tomás Mulcahy's Avatar
 
🎧 15 years
Quote:
Originally Posted by haysonics ➡️
I have read accounts of studios modding their U67s to give an upper mid-range boost.
Odd, I thought it was the other way around? Neumann's in general are bright. U67 certainly is (at least the two I used once were anyway) And EMI Abbey Road had a tailored EQ box to lower the boost in their Neumanns- In=Flat Out=Boost. Do 67s get brighter with age?

In general the move away from valves is because of heat. Makes them drift, break and (at the time) manufacturing tolerances were nowhere near as tight as silicon can be. Ans as you said, the PSU is another major source of unreliability.
Old 21 hours ago | Show parent
  #703
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haysonics's Avatar
 
🎧 5 years
Quote:
Originally Posted by Tomás Mulcahy ➡️
Odd, I thought it was the other way around? Neumann's in general are bright.
If you have generally found Neumann's to be bright then that is what you found, and I have no argument against that because I can imagine myself as Frank Sinatra or Bing or anyone else having sung through ribbons and then one day I sing through a U47 and I find that thing is bright !

Quote:
Originally Posted by Tomás Mulcahy ➡️
A U67 certainly is (at least the two I used once were anyway)
I am going to make one of those unqualified statements based on no supporting evidence and say that those U67s were modified !

Quote:
Originally Posted by Tomás Mulcahy ➡️
And EMI Abbey Road had a tailored EQ box to lower the boost in their Neumanns- In=Flat Out=Boost.
That sounds like their "presence box" (RS127) that had 10 dB of cut or boost at 2.7 kHz, 3.5 kHz and 5 kHz. My understanding is that they used the boost option with the Beatles as they sang through the U48 in Figure 8 which rolls off after 10kHz. I have no idea what their engineers set it to when using a U67.

Quote:
Originally Posted by Tomás Mulcahy ➡️
Do 67s get brighter with age?
They can ! "gunk buildup" can make them darker BUT stiffening of the aging membrane is more likely to make them brighter !

Quote:
Originally Posted by Tomás Mulcahy ➡️
In general the move away from valves is because of heat. Makes them drift, break and (at the time) manufacturing tolerances were nowhere near as tight as silicon can be.
True but keep in mind those components live in a vacuum. I am not saying its cold in there. Its not the vacuum of space. But its a vacuum and I don't leave my 1952 GE 6072 powered up and so expect it will outlive me. It lives a happy life with minimal vibration. Having said that, am I going to buy a VF14 that was pulled out of a field radio used in WWII? Probably not.

Quote:
Originally Posted by Tomás Mulcahy ➡️
Ans as you said, the PSU is another major source of unreliability.
I said it was a cost factor but I am just guessing. But yes, I agree, its an additional box full of components that can fail over time.

BUT I think the U67 is relatively flat in it's original (unmodified) form and that is why it became Barbra Streisand's mic. It tamed her upper-mid screech (sorry Babs).
Old 20 hours ago | Show parent
  #704
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Tomás Mulcahy's Avatar
 
🎧 15 years
No it's not the presence box. That was a general use thing. The box I am talking about was specifically for the Neumann mics. Unfortunately I don't have the Recording the Beatles book any more. The usual U67 plot shows a bump centred around 10kHz. Most Neumanns have it. It's smaller and wider in a U87 and a KM184, and a lot bigger and wider in a TLM103 and in a U48 which appears to have overlapping 5 and 10kHz bumps. It's the Neumann sound, basically that's what I meant. I don't normally like it personally, but it was lovely on those 67s for voice. I guess that was a different thing, as you say due to aging?
Old 20 hours ago | Show parent
  #705
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haysonics's Avatar
 
🎧 5 years
Quote:
Originally Posted by Tomás Mulcahy ➡️
No it's not the presence box. That was a general use thing. The box I am talking about was specifically for the Neumann mics. Unfortunately I don't have the Recording the Beatles book any more. The usual U67 plot shows a bump centred around 10kHz. Most Neumanns have it. It's smaller and wider in a U87 and a KM184, and a lot bigger and wider in a TLM103 and in a U48 which appears to have overlapping 5 and 10kHz bumps. It's the Neumann sound, basically that's what I meant. I don't normally like it personally, but it was lovely on those 67s for voice. I guess that was a different thing, as you say due to aging?
I don't know the box you refer to but that is not saying much as the only other EMI EQ I know is the TG12345 (1967 onwards).

Here are Neumann's U67 graphs. They are smoothed out so make of them what you will but in cardioid it's bump at 10kHz is only 2bB:



My actual experience with a U67 was long ago so I'd appreciate hearing from other users regarding it's sound.
Old 19 hours ago | Show parent
  #706
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Tomás Mulcahy's Avatar
 
🎧 15 years
Yes, am aware of its magnitude I sorta loosely described how it varies in each of the Neumann I've experience with. But it's definitely audible, and a design feature.
Old 15 hours ago | Show parent
  #707
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toledo3's Avatar
 
🎧 15 years
Quote:
Originally Posted by Rob 28 ➡️
I have a maybe stupid question. I was under the impression that Neumann moved to the 87 from the 67 because of certain advantages with using FETs instead of valves/tubes. I realize the 47 was "replaced" with the 67 due to unavailability of the specific tube. But why did they move toward the FET and not keep a tube mic in their lineup until the M149?
Did engineers in the 60s and 70s feel the 87 was just as good as the former tube mics they replaced?
They moved to fet because tube technology was on the way out and it was considered an industry wide problem. Being industry leaders and innovators, they were at the bleeding edge.

With a scenario like the initial 87, they weren’t able to deliver 60v polarization to the capsule, so they knew there would be less sensitivity than the previous 67. So, at least in this regard they had to think of it as not an ideal scenario. It wasn’t until the figured out the DC converter circuit in the 89 and used it for the 87A circuit that they were able to get the full 60v to the capsule again.

The later tube designs are based around the premise of driving the output with solidstate, which is a concession to the limits of that tube design.

The return to making U67s despite the current tubes not being that good…well, it is nice on one hand yet somewhat sad as well on the other. A company that was always pushing forward and innovating, arguably refining designs, has had to go backwards. At least it is generally better than the older ones; closer tolerances, better PSU (if someone doesn’t agree, please spare me the convo about it).
Old 15 hours ago | Show parent
  #708
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Sharp11's Avatar
 
🎧 15 years
Neumann was so fed up with the quality of tubes in the early 70s, they had private contractors modding existing tube u47s by switching them over to fet circuitry. My good friend (and former gs poster) Ethan Winer did some of that work.

Which means, of course, the overall character of the mic wouldn’t be changed by a swap from tube to fet circuitry - at least Neumann didn’t think so. I have no idea, however, what the end result turned out to be, but Ethan is a good source of info. I’ll have to ask him.
Old 15 hours ago | Show parent
  #709
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Tomás Mulcahy's Avatar
 
🎧 15 years
Quote:
Originally Posted by Sharp11 ➡️
...at least Neumann didn’t think so.
Love their attitude, probably would not go down well around here
Quote:
Originally Posted by toledo3 ➡️
A company that was always pushing forward and innovating, arguably refining designs, has had to go backwards.
Ah no, it's not that bad. They've simply need added to the range. Their monitors are amazing, defnitely "bleeding edge" and they're still pushing the AES42/ digital mics which are incredible but the take-up is verrrry slow even in location sound where they are a perfect fit. I guess they're too expensive even for TV/ film folk?
Quote:
Originally Posted by Sharp11 ➡️
...Ethan is a good source of info. I’ll have to ask him.
If you do, please share
Old 14 hours ago | Show parent
  #710
Lives for gear
 
Quote:
Originally Posted by Sharp11 ➡️
Which means, of course, the overall character of the mic wouldn’t be changed by a swap from tube to fet circuitry - at least Neumann didn’t think so. I have no idea, however, what the end result turned out to be, but Ethan is a good source of info. I’ll have to ask him.
That would be very interesting to chase ... please ...
Old 6 hours ago | Show parent
  #711
Lives for gear
 
🎧 5 years
Quote:
Originally Posted by haysonics ➡️
That's a great question !

On another forum Klaus Heyne stated that the reason for the move was cost because Neumann found the manufacturing quality of EF86s dropped off and they were discarding about 70% of tubes.

While that sounds believable and may be the case I wonder if it may have also been due to a change in the market. Neumann's published U67 frequency response graph shows a relatively flat microphone (taking into account they allow a +/- 4dB variance due to capsule manufacture). I have read accounts of studios modding their U67s to give an upper mid-range boost. I can understand this considering the positive reception for the brighter CK-12 capsule that AKG started producing at the end of 1959. The 1960s C12 (and ELAM 251) had that brighter capsule and IMO the majority of favorable comments about the C12 refer to that period (including the C12A with its nuvista tube). I believe the U87 was Neumann's competing product and it's success led to Neumann retiring the U67.

And of course there is also the cost of producing the tube power supply. The u87 could run off phantom power and it had a battery compartment. It was the future. It wouldn't be long before Neumann started questioning the need to have transformers in mics. Neumann's progressive thinking has been a majour factor in their success.

That's not to say everyone was happy with a brighter successor to the U67. The U89, with its relatively even frequency response, went someway towards filling the gap left by the retirement of the U67 (though of course it didn't have a tube or transformer).
Goes to show how "better" changes depending on trends and group culture.
Old 3 hours ago | Show parent
  #712
Gear Head
Quote:
Originally Posted by Shannon Adkins ➡️
I wasn't going to bring this up, but semantics is not limited to language. So yes, you quite literally made a big deal out of nothing.
Speaking of semantics...

If people do not stop misusing the word "literally" there will literally be no word that literally means literally...literally!
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