Topic: High Frequencies In Outdoor Recordings

[mfrench]

I don't want to read all the pages again - so bear with this if its already been addressed - I do not see it addressed in your OP (which I did reread):
How were you rigged for wind protection?

[chris319]

Many of the mics listed have rising responses/HF lift, especially the PR40.

If not height then what? Wind would account for LF rumble but not for the loss of HF.

Here is the Heil Sound PR40 dynamic cardioid which has quite a rising response. It was the most promising sounding one of all. This clip is unequalized:

http://www.miclisteningroom.org/MSLMYSO/Heil_PR40_NR.wav

[mfrench]

Wind phasing could easily sweep frequencies. It happens all the time with strongly driven (strongly amplified) PA recordings,... to blow an acoustic impulse around would be easy.
I'd blame it on the Night Winds.

But more seriously, what was your wind protection arrangement?
OEM foams, upgraded thick foams, DeadRats, zeppelins??

[chris319]

Wind phasing could easily sweep frequencies. It happens all the time with strongly driven (strongly amplified) PA recordings,... to blow an acoustic impulse around would be easy.

Sounds plausible.

But more seriously, what was your wind protection arrangement?
OEM foams, upgraded thick foams, DeadRats, zeppelins??

None, and intentionally so. Eight different mics being compared. Remember, the intent was to compare the various mics. I didn't want windscreens, etc. altering the sound of the mics.

[boojum]

So far all we have us guessing.  Can you reproduce the effects?  Have you tried recording with this setup elsewhere?  This is a fine thread for theories but theories have not fixed the problem.   ;o)  Doing will fix the problem.  Try something different.   We all know what you have done is not working.   

[chris319]

I will be recording them again this very evening, but indoors. This time the mics will be up high.

[Gutbucket]

Quick example of low mic position on a string quartet recorded last night is attached, warts and all*

Microphones were positioned in the front row, ~15 feet from quartet, height was about even with the performer's shoes.  The 1st file marked 2009-10-11 sample (LR 4060).mp3 is the Left/Right stereo pair. Also attached is a second file which is the Center/Back pair recorded simultaneously marked 2009-10-11 sample (CB 4060).mp3.

*untouched raw recorded files: no eq is applied (L/R could use a slight presence bump and some top end air boost as the mics are slightly muffled by fabric over them, the Center mic even more so), levels are low, guy falling asleep to the left croaks audibly and the girl behind squeaks her seat.. yet they do it at the start of this clip so perfectly in time with the slight pauses in the music that I find it rather humorous.  If you listen to both clips you'll hear both the grunt and squeak on the left in the L/R file and the grunt in the left (front channel) and squeak on the right (back channel) of the C/B file.    Yet for a less than perfect recording at ankle level though fabric, the L/R pair sounds relatively balanced frequency wise I think.

[chris319]

Just got back from rehearsal which was held indoors. Mics were positioned immedately to the left of, and approximately two feet behind conductor at a height of approximately 6 1/2 to 7 feet. It made all the difference in the world! The high registers of the violins come in loud and clear. The only thing to deal with now is a slight hum from a fluorescent light fixture.

Back to editing.

[Gutbucket]

Sweet.  Now you just need get them to only play in the key of B and tune to that 60hz pitch. 

[chris319]

Disappointingly, the PR40 seems to have a shielding problem. They paint the thing with non-conductive paint and there is no electrical continuity between the wire mesh and ground. I hold it up to a light dimmer and I hear buzz, but the buzz is not audible to the ear. I must add, however, that I did a Joly-inspired modification by removing the inner layer of wire mesh which made an audible improvement in clarity. Still, I don't see how the grille was electrically bonded to ground.

I have a pair of AKG Perception 150s which sounded nice and sweet.

The conductor also discovered that she has a tone-deaf violinist (these are high school kids)! Oh my. She's going to have a talk with him.

[raymonda]

Chris,

If I'm understanding you, try scraping away the paint where the mesh and the body meet and soldering them together. The body should be grounded and that should solve your grounding problem.

Ray

[chris319]

If I'm understanding you, try scraping away the paint where the mesh and the body meet and soldering them together. The body should be grounded and that should solve your grounding problem.

There are two pieces of mesh: one on the end and one which goes around the inside of the cylinder. It is impossible to test the grounding through the non-conductive paint. I was going to bond the end mesh to the cylindrical mesh and then bond them both to a point inside the mic body. This will require a considerable amount of paint scraping.

[chris319]

mshilarious -

Did you ever re-record those violin samples?