Topic: Question about mic Frquency Ranges

[Shawn]

I was thinking about picking up a set of vintage neumann mics. I was searching around for info about them and noticed that the Frequency Range on them is only 40Hz to 16 kHz. Most popular mics (for taping) go to around 20 khz so I'm wondering if this is going to be a problem? and thoughts?

[muj]

I was thinking about picking up a set of vintage neumann mics. I was searching around for info about them and noticed that the Frequency Range on them is only 40Hz to 16 kHz. Most popular mics (for taping) go to around 20 khz so I'm wondering if this is going to be a problem? and thoughts?

they are flat to 16khz, frequency range is higher, just a little rolloff at the top

[Shawn]

I found a freq. plot. It looks like the rollof is pretty steep...

[BC]

Probably does not matter for PA recording, I doubt most people can really hear 16KHz stuff anyway. I say if you are getting a vintage Neumann mic it is for the midrange, not the ultrasonics.

[Church-Audio]

I found a freq. plot. It looks like the rollof is pretty steep...

Most vintage mics rarely go above 16k this is not necessarily because of the capsule, its got more to do with the mics preamp, and the simple fact is back then 16k was pretty good. The other factors are the mics housing, some people refer this sound as warm, and certainly Neumann's have been used in some very nice recordings, 16k is not really an indicator of the mics actual performance, because when that mic was built, the ability to measure the actual frequency response of a microphone was very questionable to say the least. Look at the graphs you have, I have never seen a real graph of any mic be that smooth. Looks like someones finger was on the plotter pen I would place very little confidence in vintage mic frequency response specs, and more in what my ears tell me. To this day measuring microphones still remains part voodoo part science, we can measure a speaker much more easily then a microphone. Remember that when your looking at frequency response specifications of a mic.

[Shawn]

Thanks for the help guys

[drewloo]

I happened to read this re: large diaphragm mics on the dpa site recentely:

The upper limiting frequency (ULF) is set by several factors, all related to the dimensions of the diaphragm.

1. A large diaphragm tends to break up and will no longer act as a true piston. This phenomenon is also known from loudspeaker technology and is the reason why loudspeakers are manufactured with different sizes of diaphragms to handle different frequency areas.
2. The weight of the diaphragm will attenuate the displacement of the diaphragm for higher frequencies.
3. The diffractions around the edges of the microphone capsule will limit the microphone's capability of handling very high frequencies.

The conclusion is that a large diaphragm microphone will have a more limited frequency range than a small diaphragm.

[Church-Audio]

I happened to read this re: large diaphragm mics on the dpa site recentely:

The upper limiting frequency (ULF) is set by several factors, all related to the dimensions of the diaphragm.

1. A large diaphragm tends to break up and will no longer act as a true piston. This phenomenon is also known from loudspeaker technology and is the reason why loudspeakers are manufactured with different sizes of diaphragms to handle different frequency areas.
2. The weight of the diaphragm will attenuate the displacement of the diaphragm for higher frequencies.
3. The diffractions around the edges of the microphone capsule will limit the microphone's capability of handling very high frequencies.

The conclusion is that a large diaphragm microphone will have a more limited frequency range than a small diaphragm.

That is true and is another factor in the frequency response problem of vintage mics * if you want to call it a problem * But the main issue is really transformers in these vintage mics were just not as good as they are today that is why there are so many mods out there now for vintage mics. They also had a problem with diaphragm tension this was a way to overcome the sensitivity loss of a large diaphragm at high frequencies. Now we have all kinds of manufacturing processes that were simply not available with the technology at hand some 50 years ago. But again if I had to put a finger on the frequency response issue I would point more to the preamp then to the diaphragm. We now have many mics with a 1 inch or larger diaphragm that will go way above 20k. Dimorphism mass was an issue but not for Neumann they were the first to build a 2 micron think capsule in the U47 that capsule is still in use today and does at least 20k at -3/4 db.

[John Willett]

I found a freq. plot. It looks like the rollof is pretty steep...

What's the mic.?

That frequency response tells me it's a dedicated omni (IE: not a switchable pattern) and almost certainly a small diaphragm mic.

I would guess a KM 53a or, possibly, a KM 253 ?

[Shawn]

I found a freq. plot. It looks like the rollof is pretty steep...

What's the mic.?

That frequency response tells me it's a dedicated omni (IE: not a switchable pattern) and almost certainly a small diaphragm mic.

I would guess a KM 53a or, possibly, a KM 253 ?

it was a km88 (three pattern swithable) small diaphragm, but I only posted the frequency plot for one pattern. I ended up passing on the mics because they are practically unservicable if anything goes wrong with them.

[John Willett]

Probably the right thing to do.

But for a switchable-pattern mic. a frequency response that flat is virtually unheard of.

I have not seen a current mic by any manufacturer (including Neumann) that has a frequency response that flat in a switchable mic.

The polar pattern is pretty good in that mic. as well.

Probably all because it is a small diaphragm switchable, which people don't tend to do nowadays.

But, yes, if it goes wrong it will be difficult to sort.

Only Neumann in Berlin and Martin Gathard at Sennheiser UK I would say would have any chance.

[Shawn]

Only Neumann in Berlin and Martin Gathard at Sennheiser UK I would say would have any chance.

Neumann won't service them. It uses a brass diaphram capsule and if it is damaged there is basically nothing you can do. there was also another part that controlled the rear capsule that was prone to failure that can't be repaired. I was too big a chicken to sink over $1k into a vintage pair of mics that can't be fixed if their broken. especially considering some horror stories I've heard with people buying vintage mics through ebay.