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Unknown tube in U67
Old 18th December 2019
  #1
Does this U67 look legit ? Also Unknown tube in U67

Good morning, can anyone chime in and give me their opinion on this U67 ?
If i am truly lucky Mr Klaus Heyne ?
Any ideas on what tube this might be in a U67 ?
I also noticed that the thin metal wire that looks like its holding the tube in place isn't there ?
Pic below..
Also i wanted to ask anyone who could kindly point me in the right direction of a reputable tube dealer or mic tech that offers tubes for a U67.
I don't have time to learn about spotting fakes, id rather pay the extra money and get what i need and have piece of mind doing so :-)
Attached Thumbnails
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Unknown tube in U67-unnamed.jpg   Unknown tube in U67-jinvqbhia2xmdhhljgva.jpg  

Last edited by Derek Reese; 18th December 2019 at 01:15 PM.. Reason: added more pics and info
Old 18th December 2019
  #2
I sent these pics to a buddy that knows way more than me and he said the psu needs recapping,
I’m not sure how much that would cost.
The seller is charging me $8k so any help would be appreciated.
Old 18th December 2019
  #3
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teleharmonium's Avatar
 

Looks like a Telefunken EF86. There are multiple types but that one has a solid (as opposed to mesh) internal shield with a shiny rather than dark grey finish.

It's not so easy to beat that type. EF86 tend to last a very long time, but they can go microphonic.

I would not think a tube would be a deal breaker in a purchase of that amount, in any case. But if it needed replacement you might go for the tube that many consider the best: a vintage UK made Genelec (G.E.C.) Z729/EF86.
Old 18th December 2019
  #4
Quote:
Originally Posted by teleharmonium View Post
Looks like a Telefunken EF86. There are multiple types but that one has a solid (as opposed to mesh) internal shield with a shiny rather than dark grey finish.

It's not so easy to beat that type. EF86 tend to last a very long time, but they can go microphonic.

I would not think a tube would be a deal breaker in a purchase of that amount, in any case. But if it needed replacement you might go for the tube that many consider the best: a vintage UK made Genelec (G.E.C.) Z729/EF86.
Thank you for this, i thought the best tube was the nos telefunken EF806S ?
Old 18th December 2019
  #5
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Quote:
Originally Posted by Derek Reese View Post
Thank you for this, i thought the best tube was the nos telefunken EF806S ?
It's subjective so only you can say. I've never tried a TFK EF806 that I can recall.

In pictures they appear to have the same construction as the dark solid shield EF86, which could mean that they are the high testing selection from those production runs. (Or not.)

If I was getting a U67 and didn't have a selection of tubes already I would probably want to try a few good ones (meaning low noise and microphonics) to see what I liked the best. They do vary including between one example to the next of the same type.

I tend to favor a tube called E80F in place of EF86, but they are taller and there is not enough space in a U67.
Old 18th December 2019
  #6
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The tube's construction points to a Telefunken chrome plate EF86.

There is no difference in construction between Telefunken EF86 and EF806, though I have never seen a chrome plate EF806, it may exist.
EF806 are long-term tested EF86, i.e. EF86 that are pre-selected by Telefunken more carefully than the rest, then labeled and priced higher than EF86. I have not found any difference in durability and performance between Telefunken EF86 selected by Neumann, and EF806, which were not used as OEM in U67.

Read the primer on how to select an EF86 for U67 here: https://repforums.prosoundweb.com/in...ic,1141.0.html

Judging from your pictures, the power supply's rectifier was changed, and so were two B+ dropping resistors.

P.S.: Reading the latest post, above: Dirk Brauner had suggested the E80F for the KHE as an alternative to using NOS European EF86. We used the short version with gold pins which sounded very good, until we ran out. However the long version E80F sounded harsh, and upon closer inspection turned out to have a different filament construction than the short version. So we went back to NOS EF86 after that.
Old 18th December 2019
  #7
Gear Maniac
 
brewbacker's Avatar
 

Contact GS user Bowie. He got me a very nice nos amperex for mine.
Old 18th December 2019
  #8
Quote:
Originally Posted by Klaus View Post
The tube's construction points to a Telefunken chrome plate EF86.

There is no difference in construction between Telefunken EF86 and EF806, though I have never seen a chrome plate EF806, it may exist.
EF806 are long-term tested EF86, i.e. EF86 that are pre-selected by Telefunken more carefully than the rest, then labeled and priced higher than EF86. I have not found any difference in durability and performance between Telefunken EF86 selected by Neumann, and EF806, which were not used as OEM in U67.

Read the primer on how to select an EF86 for U67 here: https://repforums.prosoundweb.com/in...ic,1141.0.html

Judging from your pictures, the power supply's rectifier was changed, and so were two B+ dropping resistors.

P.S.: Reading the latest post, above: Dirk Brauner had suggested the E80F for the KHE as an alternative to using NOS European EF86. We used the short version with gold pins which sounded very good, until we ran out. However the long version E80F sounded harsh, and upon closer inspection turned out to have a different filament construction than the short version. So we went back to NOS EF86 after that.
Thank you for the link Klaus i will read it now.
So in your opinion how does this all look to you, capsule,psu etc
for 8K ?
Old 18th December 2019
  #9
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Klaus's Avatar
 

Looks like a steal.
Old 18th December 2019
  #10
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Klaus if I could ask, on the longer E80F you tested, did those have gold pins like the short version ? Is the short version, longer than a standard EF86 ?

I have many E80F but I don't think I have seen more than one length of the envelope, nor any without gold pins.

thanks
Old 18th December 2019
  #11
Quote:
Originally Posted by Klaus View Post
Looks like a steal.
Thats definitely music to my ears Klaus, thank you and have a wonderful holiday.
I will report back to let everyone know how the mic sounds :-)
Old 18th December 2019
  #12
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Klaus's Avatar
 

Quote:
Originally Posted by teleharmonium View Post
Klaus if I could ask, on the longer E80F you tested, did those have gold pins like the short version ? Is the short version, longer than a standard EF86 ?
The short ones had gold pins and used the common size envelope of miniature triodes/pentodes (EF86, 12AX7, etc.)

Quote:
I have many E80F but I don't think I have seen more than one length of the envelope, nor any without gold pins.
If interested, I can send you a close-up photo of the short-envelope E80F we used in the KHE. Just send me an email.
Old 18th December 2019
  #13
Klaus i forgot to ask you how one properly powers up a U67 ?
This is my first vintage mic and i do want to damage anything.
or is it as simple as plugging in the mic to the psu with the psu off and then turn her on ?

Last edited by Derek Reese; 18th December 2019 at 09:15 PM..
Old 18th December 2019
  #14
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Plug in before turning on the psu.. I wouldn’t turn on then plug in!
Old 18th December 2019
  #15
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I would add one step before starting up the mic:
Have an experienced tech confirm that the two voltages coming out of the power supply are within specs: +210VDC, ±2VDC, -6.3VDC -.2VDC (I recommend 6.2VDC, measured at the tube) All voltages measured with the mic plugged in and warmed up for a few minutes.

If voltages are too high, you may waste a $300 tube or stress the diaphragms of your original K67capsule. If too low, you may experience noise, low output and a sluggish performance.
Old 18th December 2019
  #16
Quote:
Originally Posted by Klaus View Post
I would add one step before starting up the mic:
Have an experienced tech confirm that the two voltages coming out of the power supply are within specs: +210VDC, ±2VDC, -6.3VDC -.2VDC (I recommend 6.2VDC, measured at the tube) All voltages measured with the mic plugged in and warmed up for a few minutes.

If voltages are too high, you may waste a $300 tube or stress the diaphragms of your original K67capsule. If too low, you may experience noise, low output and a sluggish performance.
will do thank you Klaus, is there anyone you recommend to do this in NYC ?
Old 19th December 2019
  #17
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I don't know the New York scene, but I am sure others will have a suggestion.
Old 19th December 2019
  #18
I brought the U67 home just now,
I inspected it and took a better pic of the tube,
I’m firing her up now and I’m going to let her sit for a half hour,
I will let you all know how she sounds.
Attached Thumbnails
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Old 20th December 2019
  #19
I have to say that this is a moment I will never forget,
The clarity and depth in this microphone blew me away.
I’ve heard other folks say how incredible this experience is and I’ve heard classic recordings with this mic, but never had the chance to feel it myself and I am absolutely amazed.
I’ve been trying to record a vocal and I keep getting choked up lol
I put down a fast acoustic guitar that sounds great,
So I may need another hour to compose myself to actually lay a vocal.
It takes all the best qualities of what you record and a really amplifies that 10 fold.
My voice sounds huge and present with depth and without any eq ?
How could this be ?
It’s like a conversation with a loved one.
I’m going to need a little time getting used to this and the mic, but wow I feel truly blessed.
I am going to finally record the last 50 songs I wrote.
And all of this using a focusrite scarlett lol, i had to borrow an interface from my Uncle because i sold mine.

Last edited by Derek Reese; 20th December 2019 at 12:13 AM.. Reason: adding more info
Old 20th December 2019
  #20
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Out of curiosity: what was your main mic (your baseline and comparator) until got the U67?
Old 20th December 2019
  #21
Quote:
Originally Posted by Klaus View Post
Out of curiosity: what was your main mic (your baseline and comparator) until got the U67?
A pair of Neumann u89's

Started with an Audio Technica 4033a for many years, moved to a FLE 47 then to the U89's
Old 20th December 2019
  #22
Few more pictures, i sent Neumann the serial number in hopes of knowing what year this one is.
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Old 21st December 2019
  #23
Capsule close up

I took some close up pictures of both sides of the capsule and wanted to share them.
The front capsule looks great, but as you can see the rear capsule's gold has worn away a little.
If you zoom in you can also see a few small wrinkles on the top portion of the rear capsule.
Is this terribly bad ?
Ive only tested the mic in Cardioid which was irresponsible of me, gonna test the other polar patterns tonight.
I am waiting to hear how old the mic is, comparing serial numbers with a few other GS posts, seems to be early 1960's.
Attached Thumbnails
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Old 21st December 2019
  #24
I had a u67 around #400 and that was the first years batch. I think I've read they made about 400 a year, don't quote me on that. Neumann will get back to you with an exact date though
Old 21st December 2019
  #25
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Congrats Derek!

The second U67 RI I sang through, did remind me of the "U67's of Yore" vocal recordings...
Chris
Old 21st December 2019
  #26
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Guys, how would you describe the U89i in comparison? (vocals)
Thanks, Chris
Old 21st December 2019
  #27
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Klaus's Avatar
 

Quote:
I am waiting to hear how old the mic is, comparing serial numbers with a few other GS posts, seems to be early 1960's.
I had sent you a PM yesterday with Neumann's shipping record (May 1963) for a U67 two number off of yours, but it somehow disappeared.

I had also mentioned in my response that the dates Neumann keeps are NOT manufacturing, but shipping dates to the company's customers (importers, wholesalers, retailers turn-key studio installations). So keep that in mind when you get the "official" info from Neumann which, these days, erroneously refers to manufacturing date.

In most cases, Neumann's manufacturing and shipping dates are fairly close (a few weeks/months) but there have been cases where the gap between manufacturing and shipping was more than a year. In such cases only authentication of build-characteristics (type/series of component parts, dates on capsules, etc.) will tell when the mic was actually made.

P.S.: Your capsule is a replacement K67 made in 1978.
Old 21st December 2019
  #28
Quote:
Originally Posted by Klaus View Post
I had sent you a PM yesterday with Neumann's shipping record (May 1963) for a U67 two number off of yours, but it somehow disappeared.

I had also mentioned in my response that the dates Neumann keeps are NOT manufacturing, but shipping dates to the company's customers (importers, wholesalers, retailers turn-key studio installations). So keep that in mind when you get the "official" info from Neumann which, these days, erroneously refers to manufacturing date.

In most cases, Neumann's manufacturing and shipping dates are fairly close (a few weeks/months) but there have been cases where the gap between manufacturing and shipping was more than a year. In such cases only authentication of build-characteristics (type/series of component parts, dates on capsules, etc.) will tell when the mic was actually made.

P.S.: Your capsule is a replacement K67 made in 1978.
I apologize, i didn't see your message.
Was curious to know your thoughts on the recent capsule pics i have provided ?
good shape, decent shape ?
I checked all polar patterns just now and the mic sounds wonderful.
The man who sold this to me said he was pretty sure everything was original and nothing has been replaced, but its all good.
Old 21st December 2019
  #29
Quote:
Originally Posted by chessparov2.0 View Post
Guys, how would you describe the U89i in comparison? (vocals)
Thanks, Chris
compared to the U67 ?
worlds apart through my ears.
The U89 i did vocals with for a few years, although i loved the sound of the U89, if i had to compare the differences, i would say that the U89 doesn't have the same bass warmth and response hence the tube i guess.
That airy brilliance on the top end of the U67 really shines also.
I would say that the U89 sounds flatter in general, but it sure takes eq well :-)
Old 21st December 2019
  #30
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Quote:
Originally Posted by Derek Reese View Post
Was curious to know your thoughts on the recent capsule pics i have provided ?
good shape, decent shape ?(...)
The man who sold this to me said he was pretty sure everything was original and nothing has been replaced, but its all good.
Well, the capsule has been replaced, as I mentioned, but at least it was the correct Neumann replacement.

The mic has been dropped and the capsule whiplashed a few times (basket bite marks in the protective Nylon collar), which distorted one of the diaphragms at the top (wrinkle). Whether that's audible or detrimental to the frequency balance of the mic, only you can determine.

I have little concern about the unprofessional cleaning attempt that removed some of the gold. It wouldn't be enough to affect an otherwise healthy capsule's performance (if indeed it is otherwise healthy).
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