When is Hypercardioid a Bad Thing?

[bgavin]

Is there a time when a cardioid such as the AKG D112 is preferable over the hypercardioid of the ATM25?

My question is about the back-side sensitivity of the ATM25, where the D112 has none.

 

[Scinx]

If you were looking at a painting in the dark, and wanted to see a specific part and nothing else - youd go hypercardioid - maybe equivalent to a pen light. If you want to see a little more, then get a flashlight - cardiod. If you want the whole thing - turn the room's light on with an omni.

 

[Scinx]

Im assuming you are using these for kicks - so hyper might not give you as much sound swirling around in the shell whereas it will give you the distinct hit of the beater (or whatever you are looking to record it at). Cardiod might give you more
Alternatively - perhaps the front of the drum is facing amps and you dont want to have them bleed into the kick mic - hyper would be better.

 

[bgavin]

My understanding is the hypercardioid is more tightly focused in the primary direction. But... the plots also show it has a very focused sensitivity in the reverse (180-degree) direction.

In a tom micing situation, would this not expose this type to picking up more cymbals, etc, that are directly behind the mike?

What differentiates a Super Cardiod from a Hypercardioid? Semantics or ?? I can't find much on the Sennheiser/AT sites to differentiate the two.

 

[Scinx]

Ok - lets see if I can be a little clearer cause my last post was rather ridiculous...
We will split this into cardioid, hypercardioid and supercardioid (abbreviated C, H, and S)
H and S have narrower focuses - they accept less from the back sides whereas C accepts less from the back. Acting as if the mic is pointing at 12 O'clock:

 

[Scinx]

C is best at rejecting stuff coming from 6 Oclock, but accepts some signals from 4.5 (between 4 and 5) and 7.5 (between 7 and 8) OClock
S is best rejecting stuff at 4.5 and 7.5, but accepts some from 6
H is best rejecting stuff from 3.5 and 8.5, but accepts some from 6


Knowing this - if you place the mic so that the cymbal is 120 degrees offaxis - youd want a Supercardioid over a Hyper over a Cardioid. What picks up the most ambient sound? C, then S, then H. It depends where the mic is pointed in relation to the other sounds you dont want it picking up. You are correct that H and S pick up from the rear - but they pick up less ambient noise overall..

 

[Big Kenny]

I liked the art post,
BK

 

[bgavin]

Thanks for the lucid explanation. The polar response charts kinda show that, but the words help.

The intent for my ATM25 are kick, rack tom, and floor tom. I'd like to keep them free from as much bleed-through as possible.

I'm also looking into using these mics to record the bottom side of the toms, so they are more isolated from the rest of the kit noise.