Does Preamp Noise Really Matter? (FAQ Series) 

huh i really thought you were giving away 5000 sm7bs. i am in utter shock😫😫😨😨😨😨

Interesting. I will not 😊.

Late to the party:, yet still: If Nyquist noise in a 20 kHz bandwidth from the 150 ohm output impedance of the SM7b is the limiting factor, then the ultimate (S+N)/N ratio we can obtail with 1.12mV from the mic due to audio is 74 dB: Noise voltage = sqrt (20'000) * sqrt(150) * 0.13 * 10E-09 ~ 225 nV. (S+N)/N ~ 20 * log10(1.12E-03 / 225E-09) ~ 73.9 dB. However, according to the SM7b datasheet, the magnetic shielding of the mic is not all powerful, and residual mains hum pickup may be the actual S/N ratio limiter, as opposed to Nyquist noise.

Yes NJ! Soothing! 😄💛

I don't like white noise though, it's annoying for me

Sooth thy everyone!

😂

I can't imagine a situation where I'd want to add 20db of 1776 on a vocal tbh, or use a 1776 on a vocal at all. A bass, sure, particularly heavy guitar perhaps, parallel on a snare with all the buttons mashed in maybe, but a vocal? Not really the right tool for the job in part because they're noisy and how they respond to vocals at high compression levels tends to just have them clamp and not let go, kinda like singing into a wet pillow. An LA2A lends itself much better for that job, smooth and syrupy by default, Same goes for a fairchild, and if you need more normalization, combine either with an SSL and you can get more compression than you'd ever want and still maintain something that sounds like a vocal.

@@jttech44 it’s more of a stylistic thing in the type of music I make. I like the way you hear the “wetness” of the compression in denser mixes. Besides, if it’s good enough for CLA it’s good enough for me haha.

​@@jttech44 it's beyond standard for certain types of music...

Yeah. I’d lump a lot of those professional tech requirements in the “being a stickler or wanting 0 noise” category. Also, I don’t know about audio books outside of audible, but the requirement verification seems to be completely flawed. They measure noise floor when someone isn’t talking. This means a gate can pass the threshold, but once the narrator starts speaking again all the hiss and ground loops come back in. I noticed this very recently. For audio books and those mediums that have strict noise floor standards, I think the proper mic selection is going to be a condenser with a decent output, and a low self noise.

@@Podcastage I have never tried to record audio books but the ones i have listened to on audible sounded so bad i deleted it, a few years later I downloaded it again and same thing, terrible audio quality. What you are saying makes sense, only thing with a condenser mic is getting rid of room reflections.. I think I saw one of your videos a while back about sound treatment but do you have a more recent video on what your using currently ?? looks like you just have some acoustic foam from what i saw in a few shots of your room. I set up some make shift stuff that gets rid of most of but not all reflections but I still hear a few

Holy smokes. Thank you so much for the support. It really helps the channel out a lot. I really appreciate you very much.

@@Podcastage Love your videos, the have been an enormous help to me.

Yes. Preamp noise is part of the analog signal chain; increasing gain in OBS takes the analog noise floor and raises it with the rest of the signal. Anything you do farther into the signal chain than the preamp itself will also affect preamp noise in the recording.

Yes, but it's often worse. Digital gain will increase noise floor linearly, whereas analog noise isn't necessarily linear. You should always make sure your recordings are gain staged accurately for this reason.

Sounds like it could maybe be some weird ground hum or something!

@@monkeyplusplus you think I could fix it somehow?

@@mirzaangon If it is ground hum, you could try making sure that your whole setup is plugged into one outlet to eliminate a ground loop. If that doesn't work, then if it's not too much of a pain you could try plugging your setup into different circuits in your house - there might be something causing AC line noise somewhere. Try turning other stuff off like lights, or anything with a motor or dimmer. There's a lot to find by just searching google too - lots of people have this problem, so you aren't alone. Good luck!!

@@monkeyplusplus the problem is I'm using a laptop and it's still there 😂

Cheap interfaces are usually clones of existing interfaces but they tend to remove components to save cost. What you're hearing is an oscillation likely caused by that process combined with something being a little out of spec. Usually they get away with removing filtering from the circuits which can make them unstable, and to further the problem, you might plug it into a different computer and have different oscillation, or no oscillation at all. If you have a powered USB hub, that's worth a try.

Ha! That's just what I'm doing with my podcast :D Back when I started I just bought the cheapest pre amp possible...but now I saved up and ordered the SSL 2. It does all I need and can be considered a very low noise interface :) at least to my current situation it'll be day and night

Maybe with plugins such as isotope or others...do a Google search...

There’s the new Adobe A.I. thing. I think it’s called like Adobe Podcast or something. Try that out. I heard someone’s audio with a mic multiple feet away with multiple guests with a ton of reverb and BG noise and it turned it into a VERY listenable podcast.

Very interesting. Thanks for the comment.

and actually my last shorter cable is mogami... even with good cables we can still meet these issues. (bad cables should be even worse)

Yeah it gets very noticeable.

Izotope spectral analyzer coming in clutch for that background of the noise floor.

Yes, digital makeup gain scales linearly, analog gain often does not, only appearing at the extremes on well designed/maintained pres/comps, which is something that a plugin can't emulate, you need the actual hardware to pull it off.

That’s why I said it’s a worst case scenario. That’s for multiple reasons. 1) All mics aren’t going to be the SM7b with gain on your interface at 100%. 2) You’re not capturing any of the room tone which would be picked up by the mic. 3) In a recording, you will use gating/expansion. 4) When mixing, everything isn’t set at the exact level you recorded at, a lot of stuff is pulled down significantly and EQed to fit amongst the mix.

Also, preamp noise is a uniform noise floor, so if you’re gentle you could use spectral denoise to remove it if it’s really an issue. Would likely be for really bad cases because it also pulls out some of the sound source as well, but it’s possible.

@@BandrewScott For the record I totally agree with the conclusion of this video. My only real observation in my TL;DR post was pointing towards DAC noise possibly adding more noise than the preamp itself. Edit: I would hesitate to call that a "Worst case scenario." Wouldn't it be more like "Hey, you're doing this wrong".....?

Analog compression before your preamp will fix your "actors with bad etiquette" problem. CL1B is a good choice, very very transparent, and can buy you another 10db before clip with very low noise. Also, Hollywood records loud parts, like yelling or screaming, separately. It's often dubbed, or, cut in as a separate scene, which avoids this problem altogether. Your "you can't just lower the gain for soooo many reasons" is ridiculous, of course you can, and you absolutely should. If you're doing broadcast stuff, mic etiquette is your actual issue, not your gear. Train your actors to back off the mic if they need to get loud, and train them how to sound loud without being loud, neither are hard techniques.

​@@jttech44 1."Analog compression before your preamp" Bhahaha, wtf this even means? U can't compress your signal before preamp, cose you need preamp to record condenser mic, you need phantom power first. Wtf you even talking about? Compressors always going AFTER preamp. And even best of the best compressors - always have shitty signal to noise ratio, its much much worse than preamp or ADC STNR. Why do ever need to compress your signal exactly for better STNR now days? Its stupid, we not living in 80-s, when compressor really helped with STNR, cose ADCs was complete shit. And with good mic, good preamp and good ADC, in 2022 - ADC is always the weakest link in STNR comparison. Analogue compressors now days only need for tracking and color, not for better signal to noise ratio... they only make it worse. 2. "Your "you can't just lower the gain for soooo many reasons" is ridiculous, of course you can, and you absolutely should." No U CAN NOT. If you say so - u never worked in professional voice over studio. Reasons for that - is plenty. I can even think about that as a question. I can name you 3 main reasons -1.Time, 2.Post production, 3.U dont know what you voicing. U can scream, and you can whipser in 2 same seconds. 3."Actors with bad etiquette""Train your actors to back off the mic if they need to get loud" Its not bad etiquette, wtf are talking about? Actors have HUGE volume range. And they need to scream, they have to. It does not even matter - far away or onto the side of mic, they gonna "clip" you, no matter what you do. And specially little girls gonna clip your ass everyday. Do you even worked with one? Also - u cant go to much far away from mic, cose when you doing voice overs as a proffesional voice over artist, you 80% of your time is sitting on a chair, not standing. Try to work 12 hours in a day standing and performing in game dev for example, you will be dead in 3 hours, and actors have 3-6 studios in a DAY. Im know what im talking about cose i working as sound engineer at 5 studios at the same time and as voice actor on 20+

It's Dynamic and it means the microphone has a magnet in it and the movement of the diaphragm within the magnetic field generated by that magnet will generate the output signal for the mic. Also, the overwhelming majority of dynamic microphones do not require external power to function.

@@Podcastage Thanks for the explanation, but I knew all that; it was a joke. About your rather unusual pronunciation of the word. Sorry.