In regards to my Shure Ksm27 microphone

M.C.Gray

M.C.Gray

New member
For the sake of conversation if you are recording someone with a deep voice there are options on the back of my microphone id like to get more insight on. The options are a flat response, LF Cutoff that provides an 18 dB-per-octave cutoff at 80 Hz, LF roll off that provides a 6 dB-per-octave roll off filter at 115Hz. Im feeling the LF cutoff is the best way to go, but my question lies in the attenuation aspect it is either 0dB or -15dB which the manual says 0dB is more normal-quite levels and the -15dB is used for more of stuff like guitar amps, kicks, snare etc. So my question is would setting the level to -15dB be to overzealous for recording someone with a deep voice? Or will vocals, no matter what frequency will never have that much sound built up on the mic?

Thanks,
M.C.Gray
 
Yeah I would probably only go with an 80Hz filter if anything. Do you need to cut anything though? Noisy environment? Running into a compressor before the preamp or anything? You can always just try both settings as youre setting up and see what the difference sounds like
 
The only thing noisy that could pose a potential problem would be the air conditioning unit outside of my window, but that is already hard to hear. My mic runs directly into my Scarlet 8i6 and from there into pro tools, so its a pretty basic setup. The proximity effect is my main concern.
 
-15db attenuation is going to make the mic less sensitive to inputs requiring what ever is being mic'ed to 32 times as loud as it would be at no attenuation.

I would not be using the attenuation slide on vocals
 
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bandcoach said:
-15db attenuation is going to make the mic less sensitive to inputs requiring what ever is being mic'ed to.

It will require 32 times as much energy in to produce the same output, so I would not be using the attenuation slide on vocals
Click to expand...

I was hoping you would come through :sing:

I appreciate it. This is kind of what I was thinking, but just had to make sure due to me being an amateur. The mic currently sits upside down and at a 90 degree angle. If moving it somewhere in between a 90 degree to 45 degree angel will lessen the chances of a proximity effect right? or am I wrong on that?
 
proximity effect is the name for the increase in bass response due to the distance between the mic element and the source

- it is why some vocalists try to swallow their mics

- you reduce proximity effect by moving further away from the mic not by changing the angle

- changing the angle will change the sensitivity (and frequency response overall) due to on-axis/off-axis considerations
 
bandcoach said:
proximity effect is the name for the increase in bass response due to the distance between the mic element and the source

- it is why some vocalists try to swallow their mics

- you reduce proximity effect by moving further away from the mic not by changing the angle

- changing the angle will change the sensitivity (and frequency response overall) due to on-axis/off-axis considerations
Click to expand...



let me see if I get this right.

-Do not by any means put the mic the vocalists mouth? :) haha had to add a little humor.

-Moving farther away from the mic lets the diaphragm of the mic open/close naturally without a bunch of unwanted frequencies crowding it?

- is that axis based on a (x,y) concept? Or is it more based on the radius and diameter of the mic? Perhaps the cardioid concept has me puzzled....(see figure 4 in link for more reference)


This is where I have gotten all my information from in case I have missed something. http://cdn.shure.com/user_guide/upload/918/us_pro_ksm27_en_ug.pdf
 
yes

yes

on-axis is directly in front of the microphone and the logo as described on page 4 (think of it has having the switches on the back of the mic) - moving the mic - to source position so the it is angled towards or away shifts the relationship to an off-axis position; i.e. if you were to point the top of the microphone (where the grill comes together at the end of the mic) you would be 90[sup]o[/sup] off-axis.

the polar diagram is indicative rather than prescriptive/proscriptive - the point where you see +5db is exactly in front of the mic (we are not told how far away the source is though, just given a spl and weighting). the back of the mic (switch side) is where the blip in the caridoid response is

x-y-z is the normal way to think of this btw, but within limits: you cannot integrate (think calculus) each of the polar response patterns into a solid shape that shows how the microphone responds in all dimensions - think front back and sides and maybe no more than 60[sup]o[/sup] off center
 
bandcoach said:
yes

yes

on-axis is directly in front of the microphone and the logo as described on page 4 (think of it has having the switches on the back of the mic) - moving the mic - to source position so the it is angled towards or away shifts the relationship to an off-axis position; i.e. if you were to point the top of the microphone (where the grill comes together at the end of the mic) you would be 90[SUP]o[/SUP] off-axis.

the polar diagram is indicative rather than prescriptive/proscriptive - the point where you see +5db is exactly in front of the mic (we are not told how far away the source is though, just given a spl and weighting). the back of the mic (switch side) is where the blip in the caridoid response is

x-y-z is the normal way to think of this btw, but within limits: you cannot integrate (think calculus) each of the polar response patterns into a solid shape that shows how the microphone responds in all dimensions - think front back and sides and maybe no more than 60[SUP]o[/SUP] off center
Click to expand...


This makes a lot more sense now and I have a more deeper respect for my mic.

The x-y-z is a formula or just variables within the polar diagram? I have not exactly reached the level of calculus in my schooling, but we have touched on subject very briefly though. I have to take 4 calculus classes so any insight into the subject will be much appreciated.
 
for the polar diagram we can see a x-axis and a y-axis the x-axis is the on-axis line, the y-axis is perpendicular to it (right angles). If we were to add a z-axis it would come straight up from the diagram at the centre

x-y-z is the three dimensional space used for identifying objects - we live in 3-d space so every movement we do can be reduced to a series of equation in x, y and z if we wanted to pursue it

the phrase calculus simply means calculations or analysis

there are two forms: differential and integral. Discussing these is really beyond the scope of fp

maybe check this out Calculus -- from Wolfram MathWorld which has lots of offshoot links to explore it further or this one Calculus for Beginners
 
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This is the point where I have completely understood what you have said(for once LOL), but I can no longer put the thoughts into words at this point to portray that. I will definitely check out the link and study it farther on my own time, I do appreciate the help and all the insight you have given. This conversation has given me something to chew on for a bit and try to apply it in the early stages recording. Though we have touched subjects outside of FP it is making me strive to digger deep in depth about other aspects of my studies.

M.C.Gray
 
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