Mics and Rooms- sensitivity?

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CoolCat

CoolCat

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Ive been watching of yt of microphones and the ocean of mic comparisons and reviews. Something that the Reviewers come to "in conclusion" is, over and over, is "this mic isn't very good for a noisy room" aka too sensitive. Or "I didn't choose the U87AI because it picks up everything" "the TLM 103 picks up my neighbors dog barking!!!" etc....etc.... so even the holy grail $3500 standard mic of history of gear lust isn't that great for bedroom apartment or basically noisy rooms.

Its not really the TLM103 or U87AI but the sensitivity of these LDC's. (and a noisy room)

How many HR studios use 28mv/pa or aka higher sensitive mics?
Why deal with the hassle if they are too sensitive requiring a great room and isolation, why?
Even the TLM 103 is 23mv/pa, that's pretty "hot" or sensitive mic for a average apartment noise level.
MXL 67 is 15mv/pa, RODE NT2 16mv/pa, KSM32 16mv/pa..(my new test-drive Antelope Audio Solo Mic 18mv/pa had me hanging pillows and such to help the mic?)
Neumann U87i 8mv/pa, 414EB 6mv/pa, SM81 6mv/pa
Senn 421 2mv/pa, SM7b 1.12mv/pa

Makes me wonder "How much does a HR hobbyist spend working their room over $$$ to make the $3500 U87AI sound good?"
And Not to leave out Sensitive Mic patterns have more reach, pulling in reflections off walls and whatever else...is it just the wrong mic for many?

Anyone want to share success story's or "tips" or things they've done that worked really well in bedroom studio or traditional average noisy home studio environments?
what mics they chose, or did you isolate the whole room? Or what became your FAVORITE MIC that rejects noise and sounds crisp and clear.?
Or did you cave in and rebuild the room acoustically? Does Hyper-Cardiod work or make things worse?

what's the maximum noise floor you accept on a track? I notice with a 28mv/pa sensitive mic(KSM44) the Input meter can be as high as -45 Idle!...with a noise gate -120 dead silent, but those have their chattering and don't really get rid of the background noise..lol What noise floor do you get with a high sensitivity mic, Im curious?

I thought about posting this in the sound room section but then accepting a room "as is"....... made it more a Mic question.
 
I use LDC mics (I have four that I use primarily - an 87 clone, a 67 clone, and a 414 clone) in my large bedroom studio setting. They are incredibly sensitive to background noise.

The biggest issue for me is that I like to record a lot of solo acoustic guitar. So.... it's pretty simple really - I know what I can do and what I can't. And, roughly, when. I live in a nice neighborhood in McKinney, TX - but it is a neighborhood. I have to deal with kids, dogs, leaf blowers and mowers, the guy down the street who works on cars and motorcycles, cars and trucks driving by, etc, etc. So I record when the coast is clear. Usually on week days when people are at work and kids are at school - or later in the evenings. I turn off the A/C or heat before I start capturing. My room is not properly treated - so to work around that I use 4-5 regular boom-type mic stands that I extend in the shape of a "T" - and then I drape large king sized quilts and blankets over them and place them around where I sit or stand to record. This deadens the room considerably. Plenty for my purposes. It works. So that's how I roll.

When everything is quiet outside - and everything is quiet inside my house, ie: wife, dogs, A/C, etc - it is dead quiet and a near perfect environment for the quietist of captures.
 
I always smile when I read those kinds of comments. As long as where you run your gain control is noise free enough for you, the mics only pick up different amounts of background when the patterns are different, the placement of wanted to unwanted sound is different, or the mic's low cut removed something down low? I've never thought about mics not picking up things as a 'feature'? Ribbons are the worst, they make the room a much bigger component, and I suppose omni's are worst. A mic doesn't know the difference between noise and a voice or instrument. If it's captured, it came from the right direction?
 
Record yourself eating a dynamic mic and then two feet back from a condenser. Oh shit the condenser picked up too much room noise!
 
Record yourself an inch from a condenser and then a 2 ft back from a dynamic... how much room noise do you have now, along with preamp noise since you cranked the gain?

There is a HUGE difference in your voice level between an inch and two feet, so the comparison is a bit of a red herring.
 
I used to be very careful to only record with a LDC when the room was dead quiet until I discovered that my mic's weren't picking up as much as I thought they were. I does matter what I'm recording and how close the mic is from the source though.
 
bouldersoundguy said:
Yep, it's largely the typical distance from which the mic is used.
Click to expand...
Indeed, remember, SPL falls off as the square of the distance* so, VERY roughly, a mic at 10 inches will get 100 times less signal than one at one inch. If we take a dynamic to have a sensitivity of 2mV/Pa (no, I agree, not many are that hot but brain needs to KISS!) we might need 60dB to get a neg 20 signal in the DAW. A capacitor mic can have a sensitivity of 20V/Pa. Now, if you have the pre amp to do it, see how much **** your dynamic picks up with 80dB of gain behind it! There is by the way a mic-cake hole distance in any room where the direct sound and the reverb' field sound are at equal sound pressure. Called the "critical distance" IIRC?

The problem is that capacitor mics and LDCs in particular are not designed for and do not sound good at very close working. The inverse is the case with dynamics. There ARE now very many capacitor mics specifically designed for very close working giving the wide flat bandwidth of capacitors if that is desired.

*Not quite. It depends a bit on frequency, size of source and other things I forget now.

Dave.
 
As a ''hobbyist'' in my basement, I made my own baffles cheaply that work fine to help isolate the vocals. I don't get all willy nilly with mv/pa's and noise floors etc... I just bring the pre's up until they start making noise and adjust accordingly to what sounds good. My best vocal mic right now is a MXL V63M. Got it a pawn shop. But my first condenser was an MXL 990 which I still can't complain about. I got great results with it on acoustic guitar and for vocals.
Although I've sold a couple things, I don't do the streaming thing etc.. I enjoy having friends come over and recording their demos or just dicking around and hit the record button and see what you come up with.
 
Won't help anyone in an apartment but in my walk in basement I built a room within a room. The ONLY way I've personally found to keep me from bothering the neighbors and the neighbors from bothering me. It works
 
Track Rat said:
Won't help anyone in an apartment but in my walk in basement I built a room within a room. The ONLY way I've personally found to keep me from bothering the neighbors and the neighbors from bothering me. It works
Click to expand...
Yes, can work but there are two different issues here.
One is that of noise ingress/egress and that breaks down again. You might not be making enough noise to bother neighbors, acoustic guitar, speech even singing, but are troubled by 'noises off'. That can only be improved by closer mics, sound PROOFING*, working in the wee small hours or a combination of all three. If however you are trying to record rock guitar at 100dB SPL or drums, proofing is the only solution if you get complaints. The problem with sound proofing is that it is hard and expensive to do well and can lead to sound quality problems which are the second part of the problem.

You might be able to build your 'Room in a Room' but it can then suffer even worse acoustics than the room it is in! The only real solution is to make it very, very 'dead' and add some reverb post tracking. (this is not such a problem for VO work) It can also be a depressing place to sing or play in.

Most HR bods I will bet only have one room at their disposal and the qualities of that room will not be optimum for both acoustic recording and loudspeaker monitoring. You can of course mix and monitor wholly on cans but the pro and cons of that have been debated ad inf!

My son only really records classical guitar acoustically. Rock G and bass are DI'ed. He is fortunate that his flat in Le Havre sounds quite good and is quiet enough if he picks his time. He is however going to investigate a large 'lobby' space outside his flat, hoping to get some recordings I can share soon. I have sent him a pair of Lewitt 040 SDCs so, watch this space!

*Got called away: Sound PROOFING is not the same as sound TREATMENT. You can do the former by building a 300mm thick concrete room but it will sound ***t! You can treat a room to control reflections and maybe trap some bass but it won't make more than a dB or so's diff to sound getting in or getting out. Very quiet studios of course combine the two methods and are quiet AND nice to be in. Costafortune though!

Dave.
 
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It's hard to describe exactly what I do because I just do it.

I'm not too bothered about my mics picking up sounds from outside because in general, they come in at such a comparatively low noise floor. Sometimes, the sounds are actually quite attractive. I've had a soft reverb-y intro with sitar, bass, floaty drums and saxophone and as it ends, you can very faintly hear my then 4-year-old son shouting "Dad !....Dad !" from downstairs. It fits in a ghostly way, really well. Then as the verse vocal starts, birds tweeting outside can be heard. That one was deliberate. I remember leaving the window open in the hope they'd be picked up randomly doing their thing.

Or a song I was recording about God sitting on a heavenly throne in awe-ful majesty and after a piece of silence, you can hear seagulls or some birds cawing and it sounds incredible to my ears. It came as a shock because when I was recording {I think it was the bass, miked} I didn't notice them at all. It was a while later that I heard them. I had to laugh.

On the other hand, when I've had to record in a room that is next to the main road, the outside sounds are picked up ~ but only when the track is isolated can those sounds be heard. When the rest of the tracks are added, they can't be. I'd be more inclined to use a dynamic in that situation, but as sensitive as my condensers are, they can also be adjusted or manipulated to be uni-directional.

I've learned to embrace mic pick-up, possibly because thus far, it has never been an intrusion that has caused me to have to re-record. Subconsciously or unconsciously, I think this goes back to when I was a boy. Lots of songs I grew up listening to had little sounds here and there but I never particularly thought about them. Even now, I wonder if some of them are deliberate sound effects or bumps and squeaks that found their way onto the recording but were unintended. The Beatles were terrible that way. So many noises on their recordings. But they never got in my way or made me think "Aaaarrrggghhh !!! I can't enjoy this song because of that dropped tambourine or that string scape !"
 
"Anything goes" really Grim' and by that I mean it is up to the artist involved to decide on what is a "reasonable noise" in each circumstance*.
There is a difference however between "personal" recordings and those that are made for commercial release. A song that had a 'clunk' on it at bar 120 would not be acceptable (even at say -25dBFS) because the listener would be driven mad every time they played the piece. Like a typo in a novel, you have to strive for perfection whereas here we are just tiny, fleeting disturbances to the universe!

*Some months ago I read a several page article about multi-mic "spill" and how we should cease to worry about it and embrace it!
YMMV.

Dave.
 
I don’t worry about background noise - my room is semi-treated - and I have a Vocal Booth - I have a U87, an AKG 414 and a gorgeous Telefunken ELA M 251E - Since the Telefunken (about 3 years) I haven’t used the U87 much - the Telefunken picks up everything - across the country it seems - but with the vocal booth I get pure clean audio.
The Vocal booth is a larger closet with higher ceilings that’s treated - such that there are any noticeable anomalies - generally for louder stuff I can use the condensers anywhere none of the outside comes in.
 
ecc83 said:
There is a difference however between "personal" recordings and those that are made for commercial release
Click to expand...
There is, but if you hear some commercially released tracks it's surprising how noisy the tracks can be in isolation.
 
grimtraveller said:
There is, but if you hear some commercially released tracks it's surprising how noisy the tracks can be in isolation.
Click to expand...
If you mean 'pre mix' tracks then I do not have access to those but I am sure you are right.
Then there is the fact that sometimes a judgement call has to be made. A recording might be made at a venue which cannot be repeated and some jobsworth slammed a door or something! The engineers will do their best to remove the noise but at some point it might be decided to leave it at neg 40 say as doing more affects the track. (audio technology is of course advancing hugely all the time)

I am sure there are innumerable records which are quite infamous for having 'noises off'!

Dave.
 
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