Misc audio questions

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wescotte

Member
I've done quite a bit of on location sound recording but I have no real formal training. While I feel like I can generally produce a decent recording I have a lot of questions on how I can improve the overall quality of my recordings.

First, I primarily use the Sennheiser MKH60 microphone as that is what my school offers. It has three switches on it. Pre-Attenuation, Roll-Off Filter, & Presence Filter. Reading the manual it sounds like it's pretty much a low pass/high pass filters. The exact same thing be done in post so is there an advantage/reason to actually enabling them on the microphone? I assume unless I'm getting distortion I should never enable the -10DB Pre-Attenuation switch as well?

I did a shoot in a restroom at school and it's very "echoy".. I happened to have a bunch of sleeping bags in my car as we were filming a campfire scene in the woods earlier that day. So I gaff taped as many as I could to the walls just out of frame and it seemed to do wonders to reduce the echo in the space. Any other tips on how to improve sound quality in such a spaces? Or other conditions I should be aware of and how to improve them? General best practice tips? Are there better materials I can use than thick blankets?

Filming outside I use a blimp and muppet combination when necessary but is there any other general advice for improving audio recordings outside I should be aware of?

Ignoring instances where I can't use a boom/shotgun because of space constraints or just can't get it close enough... When does it make sense to use a lav (or any other type mic) instead of a shotgun (MKH60) strictly for audio fidelity purposes when recording on location dialog. Are there certain room styles where even if I can get a shotgun close enough it's better to use another style mic?

I was on a shoot recently where I was booming/mixing two different actors for a film. The one actor was just louder and projected more than the other and because I was holding the boom and mixing,adjusting the level mid take was not really something I could do effectively. So really I had to find the sweet spot in both mic positioning and level for the recorder in order to get a decent sound from both performers without clipping the louder actor.

In the past I would have just used another crew member and setup another mic but it was a very small crew and we were filming out of state and literally camping in the middle of the desert several hours away from civilization. So I couldn't just call up a friend to help out. Anyway, after that shoot I got the idea of using a Y-splitter and recording one mic into two channels. This way I could have proper levels for both actors. So while the loud actor would clip all to hell in one channel I'd still get a better recording from the quiet actor. Then the loud actor would have proper levels in the other channel where the quiet actor would be very low. Is this a decent solution? Can I ever start using them all the time when I have a free channel so I can record one mic into two channels and perhaps use it as a safety net? Like keep one channel 6-12DB lower so if one channel clips the other is probably okay? Is there any reason why I shouldn't do? Can splitting it degrade the signal in any way I should be aware of?

I believe I understand microphone polar patterns but it would be nice to be able to look at a specs sheet and really understand what I'm reading. Are there any tips, books, guides you can recommend to achieve good recordings and maybe learn some theory? I feel like most of the stuff I've learned is a collection of best practices I've developed through trial and error. I would really like to learn more theory so I can learn to develop strategies to get the best audio instead of just winging it all the time.

So if anybody has any good best practice advice or an antidotes about specific problems they solved in creative ways I'd love to hear them.
 
You've already got a better handle on this than many people who ask audio questions! The sleeping bags is a nice solution to reverberation issues with hard surfaces - and if it solves the problem, it's fine. As to the balance problem, the processes you've already started are the ones to hone - as a recordist who is also the editor, changes to your record levels can be usually solved in post if it's just a change in level. Changes in mic position are far more tricky to deal with as the sound on and off axis changes so much. If you have two people with distinctly different tonal qualities AND levels, then the boom op needs the headphones up more than perhaps usual, and then needs to try to adjust position so that distance (and the inverse square law) becomes your friend. You can usually find a position where the quieter subject is on axis, and much closer to the mic than the louder person. The trick is getting the angles right so the other speaker is still just in the front lobe of the mic, just before the sound starts to go thin as you go too far off. If the distance of the loud person is twice that of the quieter one, remember they end up a quarter of the level, not half. This is often tricky, but frankly the only real world solution, because at some point, they will talk over each other, so riding the gain is dangerous.
 
I've heard the term sound on/off axis before but I don't know exactly what it means... But I assume it related to the angle of the mic and the subject being recorded. I know when you're slightly off it can sound empty/thin... I usually just point around the upper chest but as soon as you throw in movement and multiple subjects it turns into a dance. I just wish I had more insight than just trail and error until it sounds good.
 
wescotte said:
I've heard the term sound on/off axis before but I don't know exactly what it means... But I assume it related to the angle of the mic and the subject being recorded. I know when you're slightly off it can sound empty/thin... I usually just point around the upper chest but as soon as you throw in movement and multiple subjects it turns into a dance. I just wish I had more insight than just trail and error until it sounds good.
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The "axis" is the angle of acceptance for the individual mic's response pattern. In other words, from which direction(s) will the mic have a full response to the incoming sound? Different mics have different patterns, so the off-axis rejection isn't the same from mic to mic. There are several different patterns out there: cardioid (often called "unidirectional"), supercardioid, hypercardioid, omnidirectional (accepts sound from all directions), figure 8 (which is based off two cardioid patterns)... you get the idea.

A shotgun mic is typically a supercardioid element, but what makes the mic much more directional is the interference tube (what makes a shotgun a shotgun), which is designed to reject most all sounds from the sides and rear (save for a small lobe of response from the rear, and bass frequencies which are hard to tune completely out).

A good mic kit for dialog is equipped with a selection of mics. The shotgun is the workhorse, but isn't always the best choice. It can work in most situations, but some shotguns are terrible for echo-y interiors (a skilled boom op can compensate with placement/use of the mic, but some shotguns just won't behave). In other situations, a cardioid or hypercardioid may be the way to go. The hypercardioid is often referred to around here as the choice mic for interiors, but just to clarify that: it's a necessary tool to have in the kit, and is recommended for beginners since it's a little more forgiving indoors, but once you get a feel for how your shotgun reacts you can learn how to make it work in some/most (not all) interiors. I tend to use my hypercardioid on interiors more often just because I work on indies that shoot in houses and apartments with low headroom, and the smaller size of the mic gives me a little more margin of error for keeping both out of the frame and from hitting the ceiling.
 
Alex H. said:
It can work in most situations, but some shotguns are terrible for echo-y interiors (a skilled boom op can compensate with placement/use of the mic, but some shotguns just won't behave). In other situations, a cardioid or hypercardioid may be the way to go. The hypercardioid is often referred to around here as the choice mic for interiors, but just to clarify that: it's a necessary tool to have in the kit, and is recommended for beginners since it's a little more forgiving indoors, but once you get a feel for how your shotgun reacts you can learn how to make it work in some/most (not all) interiors. I tend to use my hypercardioid on interiors more often just because I work on indies that shoot in houses and apartments with low headroom, and the smaller size of the mic gives me a little more margin of error for keeping both out of the frame and from hitting the ceiling.
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Can you elaborate on this a bit... I don't understand why it can work better in echo-y interiors... A hypercardioid's pattern has more area on axis.... So how does this reduce echo? I mean if you have less area that sound is "accepted" from then you'd think that would work better at avoiding echo. Since I understand echo as bouncing of sound. So it would be coming from multiple angles producing multiple sounds. It just seems counter intuitive to me that something with a wider field of acceptance would avoid echo.

Also, help me understand how you can strategically position a shotgun in an echo-y interior to minimize the echo?

I'm looking at the microphone polar patterns on Wikipedia and realized maybe I don't understand them as well as I thought...

1) They're 2D but I assume they extend into 3D space in the same shape? meaning a Biodirectional pattern is really more like two spheres sorta smushed together?
2) How do the db values factor in? I never saw actual db values before... I always assumed it was more like at a certain distance you had an optimal field of acceptance where you had the widest angle. So for a shotgun it was like "half way" between some predefined closest and max distance. However, now that I see it has db values associated with the grid I have no idea what exactly that means.

Lastly, the switches on mics are low/high pass filters... Is there any reason to use this or is it essentially worthless because you can EQ it in post later?
 
wescotte said:
Can you elaborate on this a bit... I don't understand why it can work better in echo-y interiors... A hypercardioid's pattern has more area on axis.... So how does this reduce echo? I mean if you have less area that sound is "accepted" from then you'd think that would work better at avoiding echo. Since I understand echo as bouncing of sound. So it would be coming from multiple angles producing multiple sounds. It just seems counter intuitive to me that something with a wider field of acceptance would avoid echo.

...
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The problem with shotguns indoors is not really echo as such. A shotgun gets its directionality by the way sound waves interact in the ported tube in front of the element. When sound arrives from on-axis, the direction the mic is pointed as if it were a gun barrel, it enters the tube from the end and also through the side ports as the wave passes down along the outside of the tube. The two portions of the wave, that coming through the end and that coming through the side ports, are in phase with each other and when they encounter each other in the tube they play nice and reach the capsule unimpeded. But sound arriving from the sides enters the ports directly but when gets to the front of the tune it changes direction in order to enter the end and come down the tube. Now when the two portions of the wave collide together in the tube their phases are opposite and so they cancel each other out. The result is direct sound from the on-axis gets down the tube to the capsule but direct sound from the sides does not. So far, so good. But put the mic in a room with a lot of hard surfaces that bounce sound easily and things get complicated. Imagine the mouth of a person speaking is in the center of one end of a pool table and the mic is in the center of the other end. The sound wave is a ball. You can roll the ball straight down the table from the mouth to the mic or you can do a 'bank-shot' and bounce it off the table side rail. Roll two balls at exactly the same time and speed, one going straight amd the other banked. They'll both get to the mic but the one that bounces off the side takes just a little longer to get there since it has to go farther. Now substitute the air in the room where we're shooting for the table and the ceiling and walls for the side-rails. Some sound from our speaker goes directly to the mic. But other portions of the same sound wave bounce off a surface and arrive at the mic over a longer path. When they bounce, they flip over in phase. When they arrive later than the direct, they also are shifted backwards in phase with respect to the direct wave. The time difference we're talking about here is far too small to be heard as echo, or maybe even as reverb, but it still has a very noticeable effect. These waves enter the mic's interference tube though both the front and side ports in varying proportion depending on the direction the reflecting surface is with respect to the mic. When this jumble of wave fronts are forced to mix together in the tube they cancel each other at some frequencies and reinforce each other at others. This selective cancellation is known as 'comb filtering' because if you graphed it with the intensity of the sound getting through on the vertical axis and the frequency of the sound on the horizontal it would resemble a comb showing a number of peaks of varying heights with gaps in between. The resulting sound is quite distorted when you compare it to the original. The quality of the sound, its 'timbre', has been seriously compromised. Other directional mics, especially hypercardiods, that are almost as directional as the shotguns, do not use the interference tube principle to accomplish their directionality and so do not exhibit the comb filtering effecct in the presence of similar phase-shifted short-term reflections.

Another reason shotguns can have issues in the presence of reflections, this time including echo, is also related to the use of the interference tube, and that is that the tube is a tuned system like an organ pipe. It's efficiency for suppressing unwanted sound is directly related to the interplay of the physical dimensions of the tube and the frequency of the arriving sound. Well designed 'guns are most directional at voice frequencies but in many cases they can become nearly omnidirectional at very high or very low frequencies. That means the high and low components of reflections - even those of a long enough term such as echos where comb filtering ceases to be an issue - arriving from off-axis can make it through almost unimpeded. Clap your hands in an echo'y room and you'll hear CLAP...clap. Record it a shotgun mic and you might hear CLAP...clud
 
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Welcome to the forum! I hope you'll learn a lot and help others to do the same.
I'll try to address some of your questions:

First, I primarily use the Sennheiser MKH60 microphone as that is what my school offers. It has three switches on it. Pre-Attenuation, Roll-Off Filter, & Presence Filter. Reading the manual it sounds like it's pretty much a low pass/high pass filters. The exact same thing be done in post so is there an advantage/reason to actually enabling them on the microphone? I assume unless I'm getting distortion I should never enable the -10DB Pre-Attenuation switch as well?
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The -10dB pad is for when sounds are so loud that your mic (or preamp) can't take it. Only use it for those cases. The high-pass is primarily for diminishing wind or handling noise, which can often be done on location if needed as it will usually be taken away later anyway, and it makes it easier to monitor the signal and reduces the risk of overloading the preamp. The only reason I would use any other eq or LPF on location would be if there weren't any audio post being done, or if something needed adjusting but several channels are mixed together, so they won't be able to treat that mic separately.

Any other tips on how to improve sound quality in such a spaces? Or other conditions I should be aware of and how to improve them? General best practice tips? Are there better materials I can use than thick blankets?
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There are several things you can do, but this has been discussed several times before and can be a pretty broad subject, so I advice you to search for previous threads in this and other sound-related forums. In short, use carpets and moving blankets, and if possible try to place them with a little distance from nearby surfaces.

Filming outside I use a blimp and muppet combination when necessary but is there any other general advice for improving audio recordings outside I should be aware of?
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A very broad question that is difficult to answer without more specifics. Learn to use the microphone pattern to reject more background noises, and in some cases it can also make a big difference to boom from below so the subjects body is blocking the sound (it's not advicable to mix booming from above and below during the same scene because of the change in tonal quality).

Ignoring instances where I can't use a boom/shotgun because of space constraints or just can't get it close enough... When does it make sense to use a lav (or any other type mic) instead of a shotgun (MKH60) strictly for audio fidelity purposes when recording on location dialog. Are there certain room styles where even if I can get a shotgun close enough it's better to use another style mic?
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Interesting question, and there are several factors that might make a shotgun less desirable in certain situations. First of all, it helps to know how an interference tube works (which is what separates it from other mics), and this was explained very well in the post above. Many therefor prefer hypercardioids or cardioids if the amount of background noise isn't an issue. In certain situations shotguns can be a problem, such as very "live" reflective rooms where sound bounces around and is coming from a lot of places at almost the same time, and also if there's a background noise with very broad frequency content such as waterfalls or rivers, where moving the mic will make a very noticeable change in the sound of the background.
Also, sometimes you really don't want the added directionality of a shotgun, since it can make situations with many people or fast movements very hard to boom.

I was on a shoot recently where I was booming/mixing two different actors for a film. The one actor was just louder and projected more than the other and because I was holding the boom and mixing,adjusting the level mid take was not really something I could do effectively. So really I had to find the sweet spot in both mic positioning and level for the recorder in order to get a decent sound from both performers without clipping the louder actor.
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This is not an uncommon situation, and there are several ways to handle it (and many have different preferences). The best and simplest solution is to talk to the actor and see if he/she can't get the actors to even out their levels (preferably by making the softer person speak up). If that's not possible, then the best solution in my opinion is to adjust the difference with the boom - move in as close as you can for the soft speaker, and move back a little for the louder (this way the background level stays more even as well). If that's not possible because of space limitations or that you take in too much of the room, then you can either set a gain that is sufficient for both, use a split cable like you did, or use two mics. Other solutions may be offered by others.

Anyway, after that shoot I got the idea of using a Y-splitter and recording one mic into two channels.
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This is a good solution for scenes with much difference in dynamics, but unless you are using an active split box I wouldn't use it all the time. The reason is that it increases the noise level (but if this isn't a problem, then by all means use it). Also, be careful so you aren't feeding two channels of phantom power to one mic!

I believe I understand microphone polar patterns but it would be nice to be able to look at a specs sheet and really understand what I'm reading. Are there any tips, books, guides you can recommend to achieve good recordings and maybe learn some theory? I feel like most of the stuff I've learned is a collection of best practices I've developed through trial and error. I would really like to learn more theory so I can learn to develop strategies to get the best audio instead of just winging it all the time.
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There are several articles about interpreting microphone specs - just do a quick search. There are also several good audio books that focus on location recording, and this has been taken up several times, so again just do a search.

I'm looking at the microphone polar patterns on Wikipedia and realized maybe I don't understand them as well as I thought...

1) They're 2D but I assume they extend into 3D space in the same shape? meaning a Biodirectional pattern is really more like two spheres sorta smushed together?
2) How do the db values factor in? I never saw actual db values before... I always assumed it was more like at a certain distance you had an optimal field of acceptance where you had the widest angle. So for a shotgun it was like "half way" between some predefined closest and max distance. However, now that I see it has db values associated with the grid I have no idea what exactly that means.
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1. Yes, it's merely a 2D representation of something that is really 3D.
2. The dB values are the amount that a sound is decreased if it comes from a certain angle. For instance, if a sound would be coming in from 90 degrees on a cardioid, it would generally be diminished around 6-7dB compared to a sound coming from straight ahead (this can differ between different models and the frequency, as all directional mics are to varying degree more directional at higher frequencies than lower).
 
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Steve House said:
This selective cancellation is known as 'comb filtering' because if you graphed it with the intensity of the sound getting through on the vertical axis and the frequency of the sound on the horizontal it would resemble a comb showing a number of peaks of varying heights with gaps in between. The resulting sound is quite distorted when you compare it to the original. The quality of the sound, its 'timbre', has been seriously compromised. Other directional mics, especially hypercardiods, that are almost as directional as the shotguns, do not use the interference tube principle to accomplish their directionality and so do not exhibit the comb filtering effecct in the presence of similar phase-shifted short-term reflections.
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So, basically if it sounds okay I'm probably not being compromised by comb filter effect? I might have to Google this and find some samples as I'm not exactly sure what it sounds like...
 
So, basically if it sounds okay I'm probably not being compromised by comb filter effect? I might have to Google this and find some samples as I'm not exactly sure what it sounds like...
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You can make simple tests to find out, such as recording yourself in the middle of a room and then when you are standing closer to a wall. Maybe sitting down at a desk and at one point have blankets on the desk, then remove them, and compare. If you want to hear something more drastic, record yourself with two mics at varying distances and then mix the two. I recommend that you record it and play it back over speakers, and not just listen with headphones as you do it.
 
I suspect we've gone too far and too fast and you're now worrying about advanced stuff that really is the running stage and we're still walking. Y splits and dual channel recording really are not for beginners (and y-splits have no practical impact on the noise level, and are routinely used in the live audio business - the small loss is a tweak on the gain. The physics say there is an increase in the noise level, but it's so minimal at normal working levels we don't worry about it.)

There are all sorts of guides to using directional mics, but the one I have never understood is pointing a mic at people's chests. Considering the narrow acceptance angle of a typical shotgun, you need to aim at the sound source, and that is NOT the chest. Indeed, when we put an omni lav mic on somebodies chest, the cavity introduces resonances that need eqing out!

The key feature of using a boom is that you MUST, absolutely MUST, be able to hear what the mic is capturing. If you try it in controlled circumstances, if you point the mic at the subject's mouth you hear a crisp, clean sound - as you move it away from the mouth it stays very similar until the mic's pick-up pattern drops off. at this point the sound goes very 'thin' and weedy. Each mic behaves differently so you need to learn the characteristics of yours. You'll find that with practice, you can keep your subjects mouth in the 'good' area. The chest area sounds very different, and far too close to the drop off into the off-axis sound. Although I'm not sure, I suspect the advice to aim at the chest makes the assumption the mic is overhead in the conventional location, so pointing at the chest as a target, means the mouth IS in the direct line, on-axis. However, if the mic is moved away from this position, the advice to aim for the chest can be very wrong. With headphones, you know when the sound starts to go, and can sort it. When I taught in a college, it wasn't uncommon to see students with the headphones off, or around their neck, or totally missing, and usually this meant their audio was rubbish. It's an aural thing, not a visual thing - and the skill isn't difficult to pick up, if you can hear. The other problem with reverberant spaces is also made worse by random aiming - after all, shotguns are not intelligent - their polar pattern focusses on what they are aimed at, so miss the mouth and point at the wall, and you hear what sound bounces off the hard surface, rather than the want sound. This often leads people to the faulty premise that shotguns mustn't be used indoors. They can be - but need to be used properly.
 
paulears said:
..
There are all sorts of guides to using directional mics, but the one I have never understood is pointing a mic at people's chests. Considering the narrow acceptance angle of a typical shotgun, you need to aim at the sound source, and that is NOT the chest. ...
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Actually the chest IS the sound source in that it acts as a resonant chamber for the voice. It's not just the air supply for the vocal cords. Think of a violin or an acoustic guitar - the sound is radiated by the entire surface of the instrument as a whole and does not actually flow out of the sound holes - the holes are there so that air isn't trapped inside to damp the vibrations. You can experience it yourself by opening your mouth and singing 'ahhhhh' sweeping up in tone. When you hit your chest's resonant frequency you'll feel the vibration in your chest wall and you'll hear a marked increase in level and an added depth to the tone that then drops off again as you go past the 'sweet spot'. Experienced actors, announcers, VO artists, and orators use this exercise to pitch their voice for optimum delivery. The higher frequencies - many consonants and plosives - come more from the mouth while the lower frequencies - the vowels and tonality - comes more from the chest, making the effective over-all point-source for the voice, its center of radiation, somewhere about just under the Adam's Apple at the Sternal Notch.
 
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paulears said:
There are all sorts of guides to using directional mics, but the one I have never understood is pointing a mic at people's chests. Considering the narrow acceptance angle of a typical shotgun, you need to aim at the sound source, and that is NOT the chest. Indeed, when we put an omni lav mic on somebodies chest, the cavity introduces resonances that need eqing out!

The key feature of using a boom is that you MUST, absolutely MUST, be able to hear what the mic is capturing. If you try it in controlled circumstances, if you point the mic at the subject's mouth you hear a crisp, clean sound - as you move it away from the mouth it stays very similar until the mic's pick-up pattern drops off. at this point the sound goes very 'thin' and weedy. .
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Alright, I'll just continue to trust my ears. It is very obvious to me (now) when the mic was pointed slightly off. I was just worried I might not recognize other artifacts like the "comb filter". I'm going to run some tests but in the end I think it's just going to come down to listening and experience. It's strange... I've been on countless productions where I got to watch a professional DP or Gaffer in action and I always learn tons of stuff just watching them work. However, I've never been on a set with a professional audio guy... Any larger productions I've been just haven't been recording audio on those days. I look forward to just being able to observe one in action and learn their tricks of the trade.

The same goes for post production audio... I've been just wanting to watch somebody just work for quite some time.

The Amateur Monster Movie is the first feature I ever worked on. I did all the on location sound recording and mixed it as well as way way way to many other things. I didn't do the the majority of sound design though as there was quite a bit of stock audio from some library one of the editors had access to... When I listen to it now I cringe at how bad it is compared to my current work. But at the time it was cleaner than most other student work I've been exposed to as I'm sure you're familiar with just how easy audio becomes an afterthought and the how it's usually done by whoever is unlucky enough to get the job. You don't know anything about film making but just want to help out? Sure, come down and we'll have you hold the boom! It's easy anybody can do it :)
 
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You guys have been giving me great general advice and I wanted to thank you all for that. Here is a clip I just ran into on the internet and was hoping we could analyze it a bit.

While we don't ever get a tight shot of him it appears the speaker is wearing a lav. So why is this audio so horrible? Is the source audio in the video not using that mic? I noticed at the very beginning of the clip you see another person walk into frame and place something on the table. You can hear his footsteps and clothing rustling. So either there a mic quite near by there or he's laved as well or it's the speakers lav is actually picking up those sounds.

So, I'm curious... Do you think it is the speaker's lav is the main source of all this audio? What methods can you use to improve the sound quality? I don't know much about noise canceling but how would you get rid of the reverb? Can you record another track with an omni directional mic that captures what the audience hears and then subtract that from the source to produce a cleaner track?

Is this just not using the speakers lav? Is this another mic altogether and if they used his source mic it would be cleaner?

Thanks again
Eric
 
It's a camera mic and that is why it sounds so bad as it is a great distance from the speaker picking up PA and room ambience!
 
wescotte said:
I kinda thought it was that but the sounds of guys footsteps/clothing at the start confused me a bit. Unless maybe they have another channel mixed in?
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More likely the camera OP taking his/her seat and nothing to do with the action in the frame.
 
Still not convinced on the chest issue - The sound from the chest cavity is pretty limited in spectral content, and needs the formants and sibilance from the mouth to provide any attempt at clarity. It's rather like a milder form of throat mic - simply unpleasant, hence the strange dip in the frequency response of mics designed to be clipped on. Nobody in the audio recording world would dream of miking up somebodies chest - the mouth is where the detail is. I'm going to add this one to my list of audio practices that only video people subscribe to. I shall continue to aim my mics at the mouth of my subjects. In purely practical terms, the chest is simply not designed to produce sound in any quantity. Using a mic a s source, just wave one around to hear that the actual level from the chest is so low that the mouth output overwhelms it!
 
I started a thread not long ago which more or less translates into aiming at the mouth vs chest.
http://www.dvxuser.com/V6/showthrea...n-about-booming-on-axis-or-lobeing&highlight=
The answer from that and some other threads linked in it, would be "it depends". I do agree with Paulears that the advice to aim at the chest does seem to presuppose that you are booming from above, where the difference in angle and position between the two is quite small. If booming from the side or below, I would probably aim at the mouth. A valid point though for aiming at the chest is that it can make sudden headturns etc less noticeable and thereby easier to follow, and you are less likely to get the sweet spot past peoples head, which in my experience is worse than being a bit too far in front.


y-splits have no practical impact on the noise level, and are routinely used in the live audio business - the small loss is a tweak on the gain. The physics say there is an increase in the noise level, but it's so minimal at normal working levels we don't worry about it.
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If it's true then that's very good news. The basis for my statement was this thread:
http://www.dvxuser.com/V6/showthread.php?267899-ZOOM-H4N-and-XLR-quot-Y-quot-Splitter-cable
I did some further searching on the subject, and the few sources I found only discuss the lowered impedance and signal decrease, which results in more gain needed but not much noise added. I can't find anything supporting Doc Bernard's claims in the thread linked above, but would love some clarification on it.
 
paulears said:
Still not convinced on the chest issue
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The "perfect" aiming/placement of a shotgun or hypercardioid mic is the notch at the base of the throat - which places the aiming point between the mouth and the chest cavity. Since you are booming from above that puts the mic slightly closer to the mouth than the chest. This way you get the formants, tone and sibilance of the mouth and throat, and the resonance of the chest cavity.


It's something like recording an acoustic guitar; directly in front of the tone hole you get too much resonance, but slightly off axis you get a much better tone. Since it's a musical instrument you have a lot more leeway, and slight changes in distance and angle can significantly change the sound.
 
It varies form person to person, and getting someone to stay perfectly stationary, just ain't gonna happen, unless they're dead or tranquilized to the point of unconsciousness. Target area would be an appropriate term.
 
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