Two U87 compared

[Jürgen Schöpf]

I own two U87s bought at different times with several thousand others in
between their serial numbers. While comparing them, I found them
particularly well matching, but I have never worked with other U87s or
with a so called "matched pair".

My question is: Are my two U87s particularly well together or is the
variation of individual U87s generally so low with Neumann/U87s?

I have measured the two in all three positions (omni, cardioid and
figure-8) at the same position (+/- a few millimetres) with the free
software RMAA and have calculated the difference between the respective
frequency response curves. You can have a look at them at
http://www.musikologie.de/U87/U87.html

Opinions? Experiences?
Thank you!
:-J

[Scott Dorsey]

=?ISO-8859-1?Q?J=FCrgen_Sch=F6pf?= > wrote:
>I own two U87s bought at different times with several thousand others in
>between their serial numbers. While comparing them, I found them
>particularly well matching, but I have never worked with other U87s or
>with a so called "matched pair".
>
>My question is: Are my two U87s particularly well together or is the
>variation of individual U87s generally so low with Neumann/U87s?

They are all very consistent. And, they stay consistent as they age.
If they aren't consistent, you send them back to Neumann and they fix
them so that they are. There is no need to "match" them because they are
all matched, whether they came out of the factory 20 years ago or today.

This is the way quality microphones are.
--scott


--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Jürgen Schöpf]

Thank you Scott!

I know, Neumann defended themselves for many years not issuing any pairs
as "matched". This myth seems to attract semi-pro and home studio
customers. On the other hand, there are mics that deserve to be selected
for use as pairs... not as expensive ones as the U87 as you suggest and
I agree!

I wanted to have an opinion on my graphs and thank you for that!
:-J

Scott Dorsey wrote:
> They are all very consistent. And, they stay consistent as they age.
> If they aren't consistent, you send them back to Neumann and they fix
> them so that they are. There is no need to "match" them because they are
> all matched, whether they came out of the factory 20 years ago or today.

[Scott Dorsey]

=?ISO-8859-1?Q?J=FCrgen_Sch=F6pf?= > wrote:
>Thank you Scott!
>
>I know, Neumann defended themselves for many years not issuing any pairs
>as "matched". This myth seems to attract semi-pro and home studio
>customers. On the other hand, there are mics that deserve to be selected
>for use as pairs... not as expensive ones as the U87 as you suggest and
>I agree!

If you send them back for repair, Neumann will send you plots of your
actual mike, with the actual acceptance tolerances marked on the graph.
The tolerances are pretty tight, too.

There are some manufacturers that do extremely tight matching for special
purposes. For example, you can buy B&K 4033 capsules that are matched to
within half a degree of phase, for acoustical triangulation work.

There are OTHER manufacturers whose entire notion of quality control is
agricultural. They make microphones, then they sort them into grade A,
B, and C, just like apples. You order two Grade A microphones and ask
them to select two that sound alike. The problem with this is that a lot
of these microphones may have similar response now, but they may not age
the same way.

Neumann has spent a lot of time and effort into making their capsules as
stable as possible. They had major stability issues with the U47 and as
a result put a lot of research into how to make sure diaphragm tension
stays the same as the materials age.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Jürgen Schöpf]

Dear Scott,

more and more questions I ask are addressed by you - it seems we share
at least some interests and, hopefully and increasingly, knowledge,
although with a continuous flow from you to me... :-) Thank you!

Scott Dorsey wrote:

> If you send them back for repair, Neumann will send you plots of your
> actual mike, with the actual acceptance tolerances marked on the graph.
> The tolerances are pretty tight, too.

This is interesting!

> There are some manufacturers that do extremely tight matching for special
> purposes. For example, you can buy B&K 4033 capsules that are matched to
> within half a degree of phase, for acoustical triangulation work.

I know B&K puts considerable effort in phase consistency - and have
never read anything on phase consistency with any other
manufacturer...and consider my B&K4011 the best cardioid in my case...
(our equipment list is at http://www.mobile-digitalaufnahmen.de/technik.htm

Regards
:-J

[Dave Morrison]

"Scott Dorsey" > wrote in message
...
> =?ISO-8859-1?Q?J=FCrgen_Sch=F6pf?= > wrote:
>>I own two U87s bought at different times with several thousand others in
>>between their serial numbers. While comparing them, I found them
>>particularly well matching, but I have never worked with other U87s or
>>with a so called "matched pair".
>>
>>My question is: Are my two U87s particularly well together or is the
>>variation of individual U87s generally so low with Neumann/U87s?
>
> They are all very consistent. And, they stay consistent as they age.
> If they aren't consistent, you send them back to Neumann and they fix
> them so that they are. There is no need to "match" them because they are
> all matched, whether they came out of the factory 20 years ago or today.
>
> This is the way quality microphones are.
> --scott
>

I had an interesting exchange with a retailer about 6 years ago when I
bought my first pair of Schoeps CMC64's. These were purchased before the
recent program of selling matched stereo pairs. Since I was also interested
in doing stereo with my '64's, I asked if I could purchase a matched pair.
To my surprise, the retailer told me not to bother as the Schoeps were so
consistent that I'd be wasting my money. This was a surprising (and
reassuring) response especially when I was TRYING to give him more money.
Was the recent move to boxed, matched pairs of Schoeps mics simply a
marketing strategy or has Schoeps suddenly discovered that they weren't as
consistent as they thought? ;-)

dave

[david correia]

In article >, Jürgen Schöpf >
wrote:

> I own two U87s bought at different times with several thousand others in
> between their serial numbers. While comparing them, I found them
> particularly well matching, but I have never worked with other U87s or
> with a so called "matched pair".
>
> My question is: Are my two U87s particularly well together or is the
> variation of individual U87s generally so low with Neumann/U87s?
>
> I have measured the two in all three positions (omni, cardioid and
> figure-8) at the same position (+/- a few millimetres) with the free
> software RMAA and have calculated the difference between the respective
> frequency response curves. You can have a look at them at
> http://www.musikologie.de/U87/U87.html
>
> Opinions? Experiences?
> Thank you!
> :-J



I bought an 87 new in 1981, and a used one about 4 years later. To this
day they work wonderfully together, whether over a drumkit or in front
of a large ensemble of singers.

My only other comment is to plug them into a really good mic pre to get
the most out of them.





David Correia
www.Celebrationsound.com

[Bob Cain]

Jürgen Schöpf wrote:
> You can have a look at them at
> http://www.musikologie.de/U87/U87.html
>
> Opinions? Experiences?
> Thank you!
> :-J

I see three absolutely identical curves. I don't believe it.


Bob
--

"Things should be described as simply as possible, but no simpler."

A. Einstein

[Edi Zubovic]

On Fri, 26 Jan 2007 19:55:56 -0500, "Dave Morrison"
> wrote:

-------------8<-----------------------------
>
>I had an interesting exchange with a retailer about 6 years ago when I
>bought my first pair of Schoeps CMC64's. These were purchased before the
>recent program of selling matched stereo pairs. Since I was also interested
>in doing stereo with my '64's, I asked if I could purchase a matched pair.
>To my surprise, the retailer told me not to bother as the Schoeps were so
>consistent that I'd be wasting my money. This was a surprising (and
>reassuring) response especially when I was TRYING to give him more money.
>Was the recent move to boxed, matched pairs of Schoeps mics simply a
>marketing strategy or has Schoeps suddenly discovered that they weren't as
>consistent as they thought? ;-)
>
>dave
>
-- I think that as to Schoeps, one shouldn't be too concerned about
consistency and they can be arranged into a coincident microphone
without any problem. A "matched pair" term, IMO, _can_ be used in
marketing as this somehow gives an impression of a hand picked,
individually measured and selected, microphone capsules. This involves
human work and can pump up the price plus this gives a fine impression
about a serious manufacturer.

But shall the buyer be able to discern such a difference between a
matched pair and a pair of "normal" microphones of a serious
manufacturer, when set up into a coincident pair, is a question.

While ruminating about to obtain a Sony PCM D1 or an alternative
recorder, browsing trough a mnyriad of information pages and sheets
from various manufacturers, I've found really nice recorders. Sound
Devices, the new 1-bit Korg MR 1000... but then I looked for a quality
microphone pair. A Schoeps CMXY 4V drew my attention but the price of
some $ 4000 or so (I think) made me to quick decide, I'll stick to PCM
D1 and its... matched pair.

Edi Zubovic, Crikvenica, Croatia

[Boris Lau]

Bob Cain wrote:
> I see three absolutely identical curves. I don't believe it.

No surprise, it's the same file all three times. Just the caption (which
is not part of the image) is different.

Boris

--
http://www.borislau.de - computer science, music, photos

[Ray Thomas]

"Jürgen Schöpf" > wrote in message
...
> Dear Scott,
>
> more and more questions I ask are addressed by you - it seems we share
> at least some interests and, hopefully and increasingly, knowledge,
> although with a continuous flow from you to me... :-) Thank you!
>
> Scott Dorsey wrote:
>
>> If you send them back for repair, Neumann will send you plots of your
>> actual mike, with the actual acceptance tolerances marked on the graph.
>> The tolerances are pretty tight, too.
>
> This is interesting!
>
>> There are some manufacturers that do extremely tight matching for special
>> purposes. For example, you can buy B&K 4033 capsules that are matched to
>> within half a degree of phase, for acoustical triangulation work.
>
> I know B&K puts considerable effort in phase consistency - and have
> never read anything on phase consistency with any other
> manufacturer...and consider my B&K4011 the best cardioid in my case...
> (our equipment list is at
> http://www.mobile-digitalaufnahmen.de/technik.htm
>
> Regards
> :-J

Now that the Schoeps/Sennheiser/Neumann matching and consistency excellence
is established, which ear owner here is prepared to submit audiograms of
their hearing acuity excellence....and more to the point the left/right
matching to within 3dB. The hardware is up to the task, but what about our
'sensory decode software' ? Most of us, even with non-damaged hearing, would
be hard pressed to meet the mic standards of matching.

Ray

[Jürgen Schöpf]

Ray Thomas wrote:
>
> Now that the Schoeps/Sennheiser/Neumann matching and consistency excellence
> is established, which ear owner here is prepared to submit audiograms of
> their hearing acuity excellence....and more to the point the left/right
> matching to within 3dB. The hardware is up to the task, but what about our
> 'sensory decode software' ? Most of us, even with non-damaged hearing, would
> be hard pressed to meet the mic standards of matching.
>
> Ray
>
>

Ray!
3dB difference in binaural hearing is easily detected by anybody,
because it tells you from which direction the tiger/lion attacks you. An
easy task for our brain, because it is wired to be quick at detecting
directions. I don't think shimpanzees are worse than we whereas they
surely lack a decent appreciation of e.g. African guitar picking
tradition in the 1950s and 1960s...

Frequency response and transient detection is of course a different issue...
:-J

[Jürgen Schöpf]

Boris Lau wrote:
> Bob Cain wrote:
>> I see three absolutely identical curves. I don't believe it.
>
> No surprise, it's the same file all three times. Just the caption (which
> is not part of the image) is different.

Sorry, I'll correct that in a few minutes.
:-J

[Jürgen Schöpf]

Bob Cain wrote:
> Jürgen Schöpf wrote:
>> You can have a look at them at
>> http://www.musikologie.de/U87/U87.html

> I see three absolutely identical curves. I don't believe it.

Dear Bob and Boris!

Thank you for pointing me to my error! I have to apologise, the "omni"
and "cardioid" images have been wrong on my website, but are correct
now. Fact remains, they are all within a 1dB range...
:-J

[WillStG]

Jürgen Schöpf wrote:
> Ray Thomas wrote:
> >
> > Now that the Schoeps/Sennheiser/Neumann matching and consistency excellence
> > is established, which ear owner here is prepared to submit audiograms of
> > their hearing acuity excellence....and more to the point the left/right
> > matching to within 3dB. The hardware is up to the task, but what about our
> > 'sensory decode software' ? Most of us, even with non-damaged hearing, would
> > be hard pressed to meet the mic standards of matching.
> >
> > Ray
> >
> >
>
> Ray!
> 3dB difference in binaural hearing is easily detected by anybody,
> because it tells you from which direction the tiger/lion attacks you. An
> easy task for our brain, because it is wired to be quick at detecting
> directions. I don't think shimpanzees are worse than we whereas they
> surely lack a decent appreciation of e.g. African guitar picking
> tradition in the 1950s and 1960s...
>
> Frequency response and transient detection is of course a different issue....

Well, when you get your ears tested it *is* a frequency response
test. You have dip and peaks and such on the chart. I tested with a
2.5db greater sensitivity in my left ear at 80Hz than I have at any
frequency band in either ear. So now I turn my head that way to check
out stuff down there... <g>

And our ears do age, how evenly right and left I dunno. I tested
a bit better than average, but my audiologist joked "You have
exceptional hearing! - For a 60 year old, that is..." (a venerable age
I have a ways to go before I accomplish, of course.)

Will Miho
NY TV/Audio Post/Music/Live Sound Guy
"The large print giveth and the small print taketh away..." Tom Waits

[Scott Dorsey]

Ray Thomas > wrote:
>
>Now that the Schoeps/Sennheiser/Neumann matching and consistency excellence
>is established, which ear owner here is prepared to submit audiograms of
>their hearing acuity excellence....and more to the point the left/right
>matching to within 3dB. The hardware is up to the task, but what about our
>'sensory decode software' ? Most of us, even with non-damaged hearing, would
>be hard pressed to meet the mic standards of matching.

The good part is that your brain more or less compensates for differences
between ears. Since you're listening through the same ears all the time
and you have visual location cues as well, the brain slowly adapts to
changes that affect imaging.

A _lot_ of people in the US have poorer hearing on the left than on the
right, due to driving in cars with the window open.

Another big factor, though, are listening rooms. Most are asymmetric
and that affects imaging very severely too.

But, my goal is to ship a record that is better than people's ears or
listening rooms. There are lots of bottlenecks in the path from the
studio sound to the ear... I just want to make sure I'm involved with
as few as possible.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Bob Cain]

Jürgen Schöpf wrote:
> Bob Cain wrote:
>> Jürgen Schöpf wrote:
>>> You can have a look at them at
>>> http://www.musikologie.de/U87/U87.html
>
>> I see three absolutely identical curves. I don't believe it.
>
> Dear Bob and Boris!
>
> Thank you for pointing me to my error! I have to apologise, the "omni"
> and "cardioid" images have been wrong on my website, but are correct
> now. Fact remains, they are all within a 1dB range...
> :-J

That's a bit more believable. :-)

However, I've never seen a mic plot anywhere near that smooth and
doubt that the variances canceled out that well when the measurements
were differenced. Does RightMark have a smoothing function that you
applied?


Bob
--

"Things should be described as simply as possible, but no simpler."

A. Einstein

[Scott Dorsey]

Dave Morrison > wrote:
>I had an interesting exchange with a retailer about 6 years ago when I
>bought my first pair of Schoeps CMC64's. These were purchased before the
>recent program of selling matched stereo pairs. Since I was also interested
>in doing stereo with my '64's, I asked if I could purchase a matched pair.
>To my surprise, the retailer told me not to bother as the Schoeps were so
>consistent that I'd be wasting my money. This was a surprising (and
>reassuring) response especially when I was TRYING to give him more money.
>Was the recent move to boxed, matched pairs of Schoeps mics simply a
>marketing strategy or has Schoeps suddenly discovered that they weren't as
>consistent as they thought? ;-)

Schoeps will sell you a matched pair if you want one, but if you pick two
off the shelf, they are matched as well as they need to be for conventional
stereo miking in most cases. I wouldn't worry about spending any more
money for matching, but again you get the plots with the microphones so you
can see for yourself.

This may not be quite as true for the figure-8 capsules as for the rest of
their production, though.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Daniel Fuchs]

Bob Cain wrote:

>
> However, I've never seen a mic plot anywhere near that smooth and
> doubt that the variances canceled out that well when the measurements
> were differenced. Does RightMark have a smoothing function that you
> applied?

Does not... The variances are within a 1 dB range. I have a pair of
Beyerdynamic MC 803 which is about that close or even better.


Daniel

[Daniel Fuchs]

Scott Dorsey wrote:
>
>
> The good part is that your brain more or less compensates for differences
> between ears. Since you're listening through the same ears all the time
> and you have visual location cues as well, the brain slowly adapts to
> changes that affect imaging.
(...)
> But, my goal is to ship a record that is better than people's ears or
> listening rooms. There are lots of bottlenecks in the path from the
> studio sound to the ear... I just want to make sure I'm involved with
> as few as possible.

I wanted to post something along these lines... Thanks for doing it for
me, Scott... ;-)))


Daniel

[Bob Cain]

Daniel Fuchs wrote:
>
> Bob Cain wrote:
>
>> However, I've never seen a mic plot anywhere near that smooth and
>> doubt that the variances canceled out that well when the measurements
>> were differenced. Does RightMark have a smoothing function that you
>> applied?
>
> Does not... The variances are within a 1 dB range. I have a pair of
> Beyerdynamic MC 803 which is about that close or even better.

I'd like to see Jürgen's plot of just one of the mics, not a response
difference but the basic response plot for one of them at any pattern.

What kind of source did you record, Jürgen?


Bob
--

"Things should be described as simply as possible, but no simpler."

A. Einstein

[Daniel Fuchs]

Bob Cain wrote:

> I'd like to see Jürgen's plot of just one of the mics, not a response
> difference but the basic response plot for one of them at any pattern.
>
> What kind of source did you record, Jürgen?

A sine sweep from RMAA. The absolute plot is not of much value here,
because the speaker's response and the room characteristics will
influence it a lot.
This test may not be entirely scientific, but it shows how similarly two
mics in the same position will represent the same acoustic phenomenon
from the same speaker. I believe it's quite sufficient to judge the
quality of a stereo pair in relative terms. It's not meant to replace a
manufacturer's original frequency plot.

Daniel

[Bob Cain]

Daniel Fuchs wrote:
>
> Bob Cain wrote:
>
>> I'd like to see Jürgen's plot of just one of the mics, not a response
>> difference but the basic response plot for one of them at any pattern.
>>
>> What kind of source did you record, Jürgen?
>
> A sine sweep from RMAA. The absolute plot is not of much value here,
> because the speaker's response and the room characteristics will
> influence it a lot.
> This test may not be entirely scientific, but it shows how similarly two
> mics in the same position will represent the same acoustic phenomenon
> from the same speaker. I believe it's quite sufficient to judge the
> quality of a stereo pair in relative terms. It's not meant to replace a
> manufacturer's original frequency plot.
>
> Daniel

At any rate I don't believe the smoothness of the plots to represent
reality. Until I know how they got that smooth I won't believe the
small difference between the mics that is shown in those plots.

I've done a lot of mic measurement and something seems fishy here, sorry.



Bob
--

"Things should be described as simply as possible, but no simpler."

A. Einstein

[Daniel Fuchs]

Bob Cain wrote:

> At any rate I don't believe the smoothness of the plots to represent
> reality. Until I know how they got that smooth I won't believe the
> small difference between the mics that is shown in those plots.
>
> I've done a lot of mic measurement and something seems fishy here, sorry.

The resolution of RMAA's measurements may not be as high as professional
measurements and plots that you get from the manufaturer. Possibly some
smoothing is applied, even to the frequency response curves themselves.
Download RMAA (it's free) and find out. At any rate, this should not
affect the difference curve much. I've seen mics that are even closer.

Daniel