A client in Germany just alerted me to this site and this particular thread. The level of respectful discussions here is refreshing.
In no particular order I referenced comments and questions that resonated, and to which I will try to respond to the best of my ability.
Klaus has profited immensely from his position as an expert, particularly as "the" expert with a vast array of special, privileged Neumann information.
Klaus has no such information, speculation to the contrary.
I have had cordial, mutually respectful relationships with the folks who run the company in Berlin since the 1980s; they ask me occasionally to help out with some minor technical stuff, like testing or seleting a VF14, and the like. I appreciate their generosity of occasionally finding obsolete parts in some dusty drawers, but that's it in terms of 'cooperation' I have never stolen or passed on proprietary Neumann information to anyone. My modification concepts veer to much into left field that this would ever be an issue anyway.
it strikes me as odd that the world’s best microphone manufacturer can’t get it right on their own star product, while somehow there are a few select individuals that really know better, know what’s wrong, and know how to fix it.Neumann DOES get it about as right as any mass-manufacturer of high end condenser mics can these days (I will come back to the capsule issue at the end of this post), especially when considering the economy of scale, current environmental and safety laws, availability of components and materials... For example, it would likely bankrupt the company if they were to source NOS EF86 on the world market, test them, reject 3/4 of them, keep enough stock for spares, etc. etc. Apply and multiply that dilemma to transformers, cables, tubes, passive components ("the best J-Fet") and it's perfectly reasonable to conclude that what they do with what they have is exceptionally brilliant.
So personally, while I respect Klaus and his background, I stay skeptical of anything he might state as facts, and enjoy his opinions as nothing more than that.Fully agreed. There are no objective facts in the realm of the senses. What is fact: my strong opinions of what I think sounds good, and which I apply to the mics I work on, are respected by the people I respect most: successful engineers, producers, artists, voice talents, scoring, ADR and Foley stages and the like. It gives me tremendous satisfaction that, when I dial in an ELA M 251 for Rick Rubin, word comes back that it is now the preferred ELA M. I mention this not with false pride, but as confirmation mainly to myself that I have not barked up the wrong tree for 35 years.
There’s no contradiction in someone being both extremely experienced and knowledgeable and also being wrong in some of their pet dogmas.Again, agreed. Two examples: 1. For years, I bypassed coupling caps with a Styrene cap of 1/10 the value, following the logic that the right frequencies will search out the appropriate cap, for smoother sailing of the signal. (You can buy these things, already wrapped, as 'Wondercaps" from a reputable capacitor manufacturer). It's bullshit, as it turned out. I was blinded to the ensuing phase shift and ugly mids. But it took me some years to correct my mistake. 2. Another misstep: using sterling silver wire as capsule lead outs. I mistook the tinny timbre that material creates as "higher resolution".
does anybody know why they designed the reissue to have the capsule sticking up higher in the head basket and what effect that may have on the sound? Klaus mentioned it with a picture, but didn't really go into detail about it.The complete capsule head- basket, switch assembly and capsule mount- is identical to that of the U87Ai. As someone already mentioned: why add more cost? It's been done that way for decades, and no one has yet complained. Yes, the wedge shape of the basket is an acoustic deflector of standing waves, and I am sure that placing the capsule higher into that acoustic roof will have a small sonic effect. But in my opinion that's way down the food chain compared to, say, addressing a crappy Russian tube.
No need to question what you hear either, just because KH says it's something or another. Trust your own ears.How many years have I been preaching exactly that? On my forum, on Gearslutz, on PRW... I think it's laziness (and then the inevitable elevation of the person who actually does listen for a living, and sometimes all day long, is touted or trashed!) Listening education can be so much fun. We would never neglect applying the same diligence in a wine tasting, or learning the pleasure of distinguishing the different odor of roses, or even the same rose on different petals. But somehow the pocket protector types have beaten this out of us, dunking our faces into (totally manipulated) off-axis response curves and other meaningless but shiny objects instead (have you ever seen the raw frequency plot of an ELA M251? Good luck not getting seasick).
Let's think about this for a just a moment. Someone that makes their living from modding Neumann mics proclaims in public that the new Neumann 67 isn't perfect and needs... modifications. Possible conflict of interest, anyone?
Guy who mods mics, says mic needs mods.I am probably even more suspicious about people's motives than you. "Follow the money" is my go-to mode when trying to understand why anyone moves with purpose in any direction. Let me step up to the witness stand and defend myself, then you be the judge: I started out doing what I still do for two reasons. I was miserable in law school and was enticed by 'good sounds' (make of that term what you wish) coming from any type of sound waves intended to create pleasure. I have never veered off the path of trying to strip off artifacts from the sound of microphones, trying to get closer to what I regard as sensual reproduction of reality.
The U67 Reissue is a remarkable feat that, were I running Neumann, I would have never taken on in the first place.
Just like the U47fet reissue, the U67 is a bold retro-move by a legacy company, when all signs point to SMD, transformerless, CMC and other soul-less fabrication. With a good capsule, and a decent tube, the U67 Reissue is very close to the original. I.e., my services are not needed. I said as much in the review: if you want that last tiny percentile, THEN contact me.
So: great mic, needs nothing, not from me or anyone else, as long as you have a good tube and capsule.
How can I date my TLM67?
Explained here:
repforums.prosoundweb.com/index.php/topic,36283.0.html
A lot of improvement in the U67 reissue can be gained with just a simple change of tube.
Replacing the tube in the Reissue is such an obvious improvement that, if you can't hear it, your recording/playback chain (or your ears) are too low-fi to justify buying a $7k mic.
The thing about Klaus is that he has built a reputation that he is the one person on Earth who can assess Neumann capsules and turn the mediocre ones into magic.Says who? Never heard that from me. The latter part is at least half right: I have found a way to de-tension the high-tension K67 into the range of a good early-mid-1960s K67. But it's an arduous process and takes too long to become a business proposition, so I only do it -free- as part of a full mod on new 87/67 mics whose capsules are too honky to send out that way.
I'm not buying 'Klaus makes magic' where no one else can- it's way too self-serving. I've watched his passive-aggressive self-promotional act for years. I've also watched how his opinion of Neumann has shifted as his personal career has taken off. Track down some old Neumann Forum posts of his and you'll see what I mean.Here comes the psychology bit from Mr. Anonymous. If you give me some facts ('opinions shifted...') I will take a deep look inside, and assess if my ever-evolving knowledge of all things microphones may now be outweighed by an agenda for self-aggrandizement. Stating your real name might give me additional incentive.
I just read Klaus’s review and I have a question. Does capsule tension change over time?
Could a capsule tensioned in the 1960s be as tight as one coming off the production line today?
Is time a factor?
One of the greatest properties of Polyester/Mylar skins: they do not age, at least not by my perception. I have virgin 1960s brass K47s, K49s and a few K67 from the early 1960s, and they sound just as wonderful as a healthy version made by Neumann today. What ages capsules: abuse, like super high SPLs and unattended contamination.
I think there might be a misnomer that the capsule is stretched over like a drum head and bolted or glued. I don’t believe that’s the case. When you turn the screws on say a kk47, I believe you’re changing the distance between the two plates therefore changing capacitance. I think the culprit is the sputtering process.
If you look very closely at the "How It's Made" video, Neumann left in an important step of capsule manufacturing: diaphragm pre-tensioning. A larger sheet of the pre-sputtered diaphragm is placed on a cylinder and a weighted metal ring is slid over this cylinder. Gravity from the exact weight of the ring tensions the diaphragm to the predetermined correct level. Then the diaphragm ring is affixed, which preserves the pre-set tension, and the excess Mylar is cut away. But don't think for a second that this is even the beginning of how Neumann achieves the exceptional sound quality of its capsules. There are many more steps that will never be shown or shared.
I understand there is natural variation, but are Neumann’s QC standards really that lax ? Hard to believe.
Now comes the juiciest bit- the notorious capsule tension issue.
This is what I know: In the early 2000s, Neumann increased capsule tension on at least one large diaphragm capsule model, the K67/87/870.
Why? How can I be certain? How consistent?
Why? Someone mentioned that it must have been the same reason why the KM184 sounds more mid-forward than the KM84. I don't think that was why. More likely, diaphragm tension was increased to reduce the rate of capsule rejects.
To explain: a condenser capsule's output is somewhat variable, due to an unusually wide manufacturing tolerance, which cannot easily be reigned in more. Neumann probably has the tightest tolerance in the business, yet even they cannot get it closer than ±2dB at any point on the output/frequency plot. That means in practical terms: one capsule can deviate from the next, or one side from the other as much as 4dB at any point on the scale. That is relatively large, compared to the tolerance of their FET mic amp/processors, which is usually ±1/4 dB (I've measured it).
The old, pre-2000 capsules were often warm, lush, full, rich, however you want to describe a pleasant-sounding K67. But what we as consumers never saw: this comes at the price of too many of these capsule being a bit TOO lush (i.e. bass-heavy, with a tendency to fold up upon 'plosives, or, worse, a tendency to mechanically distort, due to the charged backplate's electrostatic attraction, which inherently makes for a non-linear excursion of the diaphragm). As too many capsules fell out of the lower limit of tolerance range, and as the capsule is the single most expensive component during manufacturing, and as bean counters are always counting in the background, my speculation was: if they slightly increase the diaphragm tension, they will drastically lower the percentage of rejects. So that was probably why it was done, never mind the consequences to good, balanced response.
How can I be certain it's the diaphragm tension rather than some other capsule component or process? Simple: I had a fabricator make me a jig with which I can lower diaphragm tension into the previous range, with a degree of precision to make it repeatable, and, voila, the tension returned to the level it was 'in the olden days'. Doing that, and doing it repeatedly (Roundbadge who posted here, was one of the people for whom I did that) it became clear, by simple logic, that this was the ONLY deviation from earlier versions of the same capsules: if there where any other differences, like Mylar, sputtering, pre-aging, tightness of mounting screws (never loosen them-the diaphragm will crinkle up and the capsule will be destroyed- Neumann does not glue the membranes, which are only held to their tension by the friction of the screwed ring!), then reducing diaphragm tension alone would not have yielded the desired results.
My ophthalmic surgeon has a very expensive eye pressure device. If any of you are optometrists and have access to such device, I'll gladly send you two K67 capsules (one right, one tight) to "objectively" confirm even further.
How consistent? That's the part where my answers will continue to frustrate: I see quite a few brand-new U87 and a few U67 Reissues, so I have some modest sampling, but for putting a reliable percentage on that, my sampling is too low. It was pretty bad around the early 2000s (a rough guess: more than 60% were too tight) and then it got better, and then, around 2016 it got bad again (maybe more than 50%?) But this much seems clear: capsule tension on K67/870 continues to be too high and too few of them hit the jackpot. I would put the figures at at least 40% of capsules made in the last 15 years whose diaphragm tension is too high for my taste, to yield what I would define as a pleasant, balanced sound with solid, not starved bass response.
So how can there be still great-sounding capsules today, if the diaphragm tension is too high?
As I said earlier: capsule manufacturing has an unavoidably wide tolerance, so if you catch one at the lower tension (i.e. fuller bass) limit, it will be just perfect. As a consequence of the overall tighter level Neumann is aiming for, there are no longer bass-heavy K67, which, while still attractive to most, some people may have found too boomy. Those days are over. But if you were to look at Neumann's bell curve (to which I have no access, but it's usually graphed in tolerance analyses), a lot of the current capsules will be concentrated in the "too tight for comfort" range- and on purpose!
This may be in the end a case of weighing reasonable business concerns with customer expectations. And, as can be seen from postings in the net, the percentage of complainers is relatively small- which does not devalue the complaint, in my opinion. So don't chastise me for a. pointing this out, and b. doing something about it when Neumann is not. But, seriously, I would love to buy all of their lower-end rejects which probably land in the trash. There is still a chance that my above stated explanation for higher tension is wrong, and it's just a stupid, unintended change of a manufacturing component or process that's responsible for the over-tight skins.
I doubt Klaus has more information available to him than an engineer at Neumann.
I certainly have no proprietary Neumann information, as stated at the start of this post, except on one occasion, and this one is relevant to this discussion: I had sent several older and newer K87/870 to Berlin with a request for confirmation of what I heard (tight low end). They tested the capsules, and the graphs plotted from their an-echoic chamber tests confirmed without question my assertion: the newer capsule was down a good 4dB @50 from the older capsule, all else looked pretty much similar. That is just the visuals, mind you. As we all know the graphs are just the beginning... But they concluded the newer capsule was still within the published tolerance range; which was true.
The only thing I wish Klaus would have done is having looked at at least 1 other reissue. He based everything on 1 mic. Maybe that would've shown the consistency of the inconsistencies in the capsules?
That capsule in the tester was indeed horrible. I have since had two more brand new Reissues here, one with an ok but not great low end, and the latest was so well balanced, I did not need to do a thing about it, aside of recommending to the owner to throw the tube out and replace it with an Amperex mesh plate.
I hope I have covered most of the issues that were brought up about my person, my work, and the U67 Reissue in particular. Due to the flu, I also had ample time to go a bit deeper here, maybe a bit too deep. Let me know if you have more questions. and please be patient if I cannot respond right away.
Best, KH