frequency response curves

S

SalJustSal

New member
This may or may not have been asked, but I couldn't find it.

Does anybody know of a website with the different frequency response curves for the microphones (preferably modern studio mics)?

Thanks,

Sal
 
You can find them on the web sites for the individual companies. I haven't seen a comprehensive list of everyones' specs. Would be cool, though.
 
Most published mic curves bear very little resemblence to the actual products. Lemme see if I can find a curve that will show you what I mean. BBIAB
 
Ok, hopefully, this will work. These are both one inch cardioid condenser mics from well know companies.

mic-1.jpg


mic-2.jpg


So how does this help us make a decision about which mic is better? They both start rolling off around 50 Hz. Curve one only goes down to 30 Hz, so they don't line up exactly.

One of them (mic-1) has a little bump at around 8 kHz, drops, then comes up again at around 12 kHz, then it proceeds to drop like a rock. But each horizontal line is only one dB so it ain't as bad as it looks (but is that a machine run curve or someone's idea of what the mic should do?).

The other one (mic-2) "looks" a little smoother, but it's using a 2 dB per horizontal line calibration. It also goes out to 20 kHz and a little beyond (probably), but so what?

How would you (or anybody here) characterize these two mics? Which would you recommend, and why? Why should I believe either curve?
 
Well, Harvey, I wouldn't recommend either of them without hearing them--especially after all you've said about how factories average out curves and paint a rosy picture with these graphs! But, based on the graphs here is what I would EXPECT:

Mic 1 would sound brighter or edgier, due to the pumped up high frequencies

Mic 2, while not adding as much high end, I think mic two would be more transparent sounding, due to the little dips down in the midrange.

I have a feeling my post is gonna help you prove a point, but I'm into what you have to say!
 
Yes, that would be nice, but as I said, these are two curves from two well known mic manufacturers, and they used different scales. And that's one of the problems I'm trying to illustrate by printing these curves.

If you read them correctly, you'll see that both don't deviate by more than about 2dB from zero for the bulk of their curves, although the first mic doesn't go out much beyond 15 kHz, and mic-2 drops off pretty fast below 50 Hz.

"Most" one inch cardioid condenser mics are bought primarily for use as vocal mics. While it's true that some home studios look for one mic to "do it all", vocals are still the most important use of large diaphragm condenser mics. Plus it makes things a little simpler for purposes of this thread.

What can we tell about these two mics from the manufacturer's published curves? Which would be "better" for your vocals? What would they sound like? If you lived too far from any dealer, could you make a reasonable choice, using these curves?

SalJustSal and TexRoadkill thought a mic curve database might be helpful. My question remains the same; why? These are the curves for two popular vocal mics. What good does this information do for anyone here? How much should these curves influence your buying decision? 5%? 25%? 50%?

Did anybody notice that the mic-1 curve showed the mic's sensitivity (around -51 dB), which means you better have a really good preamp when you use this thing.
 
yes, I agree but...

Harvey - I understand your point fully and I'm not looking to base my decision of how good a mic would sound by the curve. I was looking for a mic that I already know has a chance of sounding good that also has a relatively flat response too.

I do understand that these curves aren't entirely accurate either, but I'm guessing most are more accurate than my perception of how the mic frequencies curves are.

-Sal
 
But therein lies the problem I have with the whole premise. Would it surprise you to know the price difference between those two mics I posted is in the neighborhood of $6,400.00? That's the difference in cost between the two mics.
 
Crawdad,

Of course I chose those two mics to illustrate exactly that point, but looking at the curves, you can't see where the $6,400 difference is - at least I can't.

From the curves it looks like they'd be within 2dB of each other from around 40Hz to about 15 kHz. That is what many companies would consider a matched pair.
 
Harvey,

You have again tapped a fascinating topic. I suppose I'm gonna have to wait to hear what the two mics actually are, but if I were led by the graphs, I damn well know I'd pocket that $6400 difference and take a shot with the cheaper mic. Actually, I wouldn't have much choice, if those were my only two choices. If money were no object, I'd buy mic #2 based on the graphs. Yet, you are saying the graphs are meaningless marketing hype, so maybe I am being misled by the curves.

I dug out the specs on the Octava 219 that I bought a while ago. I bought it because I did a session a few years ago at some local studio. Since their equipment picked up every imaginable radio signal in the area, my electric guitar was useless. They handed me an Ovation for acoustic tracks and they put this mic on that guitar. I was amazed that it sounded as good as it did.

Anyway, in the brochure that came with the mic it says:

Frequency response: 40 Hz-16kHz

Then, the qualifying statement: (the useful response extends far beyond this)

Like, what does that mean? 20-20? 15 -25? By the way, the graph that came with it is so blurry, you can't tell what anything means!

But, getting back on topic, I found it to be rather dark, but warm sounding for certain things. Yet, from the curves, I would have expected it to be brighter. So, I am curious to hear the "rest of the story" as they say. meanwhile, I'll see if I can find a curve for this mic on the net somewhere and post it.
 
I'm trying to attach a file here for the 219 Oktava. Not sure if its workin' or what.
 

Attachments

  • mk219.gif
    mk219.gif
    5.9 KB · Views: 42
OK, Harvey. It worked. But how would one go about deciphering this triple graphed curve? makes little sense to me. Does the frequency response change based on the sound pressure that the mic sees? I'm more than a little lost...
 
Actually, that's a pretty meaningful graph.

The top two graphs (in blue) show the frequency response on axis (pointed right at the capsule). The thick blue graph shows the response flat, while the thin blue roll off line shows the effect of the high pass filter switch (bass roll off to compensate for the proximity effect).

The middle yellow curve shows the response from 90 degrees off axis, with the high end drop off quite visible.

The bottom red curve is from the back side of the mic (180 degrees), showing the rejection at different frequencies to sounds coming in from behind the mic.

And the graphs I included earlier on are the Neumann U47 (mic-1) and the Marshall V67G (mic-2). If you compare Henrik's curves to the Neumann curve, you'll see that the V67 is actually closer to the U47 than the Marshall factory curve would suggest.
 
Cool! I'm gonna get me one of them!


Since tone of voice doesn't come through print, I should probably point out I am kidding.
-kent
 
The one thing about the 2 graphs I noticed was how flat the response was on the first mic, and recognizing the Marshall chart made me wonder what the first one was. The MXL looks a little uncontrolled but still pretty close to flat considering the price difference. I would have have purchased both...
If I had enough dough for a 5 grand plus mic, a $ 200 mic is like buying guitar strings...Heh heh...

Peace,
Dennis
 
You must log in or register to reply here.
Back
Top