Is microphone self noise any absolute indicator of a mic's quality or fidelity?

cfg

Member
I just did some listening experiments on spoken word using four LDC's, 2X Aston Origin's, SE X1 (dumb name for a mic), and an AKG C414 b-uls (on loan from a friend), and the results surprised me. The two origins sound like two completely different mics, and the C414 has perhaps half or less self noise than the rest. Neglecting self noise, I can't yet determine which one I favor, but the difference in self noise has me pondering the following question.

Is there any direct correlation between self noise and quality? Or, is it possible that a given mic's other qualities or attributes could overshadow self noise?
 

gecko zzed

Grumpy Mod
I think that low self-noise would be a good proxy indicator of microphone quality. That's because to get low self-noise requires hi qualityelectronic engineering, and if high quality electronic engineering is part of the build, then the rest of the build would most likely enjoy the same hig quality approach.
 

Djard

New member
I found that the use of a DBX 286S (inline) makes any microphone sound super clean. But it cannot add what I call "body" to a signal, body that is extremely difficult to add, even with the best equalizer.
 

rob aylestone

Well-known member
I think that noise is just the design - so a mic with a relatively high noise figure, but always used on loud instruments would be fine, while a mic designed for distant capture of quiet sources needs a better noise figure. I'm not even sure about 'fidelity' as a concept. Some mics are designed to be truthful while others flattering - so a measurement mic with flat response curve would be a very high fidelity mic - as in capturing exactly what it is given in the right proportions - but they sound horrible on music? I choose the mics to be complimentary to what I'm recording - never giving noise a thought, unless the chosen mic is the wrong mic.
 

Orson

Well-known member
Wouldnt the pre-amps of the recorder have just as much in put on the microphone choice?
 

CoolCat

Well-known member
I just did some tracks looking at a MXL V67G and the KSM44 was very noticeable in being much quieter.
It doesnt mean the KSM44 sounds better on sources. It might win in total silence engineering spec contest, but whats that mean? who cares?

for a typical garage band rock/indie /country kind of recording "once the drummer starts playing" this miniscule noise floor stuff means nothing to me.

as Rob mentioned distance , made me think of a choir or symphony hall recording with 25 or more mics...quiet, silence opera like, so imagine a bunch of mics with high noise floor recording a symphony or quartet, or quiet passages all sitting idle going SSHSHHHHHHHHSSSHHHSSSSSSSSSSSHHSS. So in this environment it would be great to have low noise mics right? low noise everything, as possible.

But even classical once it gets going the miniscule -db of noise floor isnt an issue on one mic....Ive never recorded large venues but simple sense would imagine the addition, accumulative noise of 25 mics versus 1 mic is louder noise.

being a gearhead its nice having a low noise mic to know what one sounds like. KSM44 has decent specs for this(7db). Ive read the Rode NT1? is the quiet noise floor mic too. I ran a comparison as I said with MXL V67G (20db) but the noise floor was noticeable only in a dead silence comparison.

from a engineers perspective, better specs is quality....noise floor specs etc...better built. better metal, better internals...specs are military grade top notch.

from a creative brain subjective color and sound shaping recording with a drummer banging away my noisy single coil Jazz bass plugged in..the neighbors dog barking.......the mic noise floor of the mic is pretty low on the problem list for me. :eatpopcorn:

add...the self noise specs on the classic U47 and 67 arent very good, either. 16 to 24db...
 
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rob aylestone

Well-known member
I think it's fair to say noise floor is very rarely an issue, and when it is - it's nearly always the wrong mic has been chosen for the job, and second, perhaps the wrong mic for the preamp, for the job. Plus 'em in - turn up the gain and if you hear the hiss - use a different mic. I have no idea which of my collection have the worst noise performance, because they all do the jobs I give them? They're bound to be different, but swapping mic A for mic B usually just sounds better or worse.
 

gecko zzed

Grumpy Mod
being a gearhead its nice having a low noise mic to know what one sounds like. KSM44 has decent specs for this(7db). Ive read the Rode NT1? is the quiet noise floor mic too. I ran a comparison as I said with MXL V67G (20db) but the noise floor was noticeable only in a dead silence comparison.


add...the self noise specs on the classic U47 and 67 arent very good, either. 16 to 24db...

The current Rode NT1 self noiuse is measured at 4.5db
 

TalismanRich

Well-known member
I remember when CatMalone was trying to improve his VO work. He had been using an MXL770 and got an NT1. I noticed a significant drop in noise. The 770 is rate at 20dBa self noise, vs the NT1's 4.5. If you are doing music with any significant volume, it would be buried in the sound. If you are doing a quiet acoustic guitar/vocal song, or voice over work, it can make a difference.

I find that most decent mics are in the 5 to 15 dB self noise, and are perfectly adequate. I also have a V67G and used it for vocals a while back on a James Taylor tune. It worked fine.
 

ecc83

Well-known member
This is worth a study: https://www.dpamicrophones.com/mic-university/the-basics-about-noise-in-mics

For those that do not know, DPA are the makers of some of the highest quality microphones around and are used by most of the 'pros' in the sound industry.

There is no mention of a link between noise level and audio quality but then the only make the best! A very loose relationship is found between low electronic noise and low resistor values. That means higher currents so a VERY low noise capacitor mic might have a heavier phantom current draw. Should not however be a problem with modern pre amps.

Dave.
 
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