Question Concerning Microphone Gain Specs

[VectorPeasley]

Hello, everyone! I'm Vector Peasley. I'm new to both these forums and home recording.

I've been recording at home with my budget microphones for seven months now--and I've learned a lot! However, with all knowledge to be had, sometimes we need a helping hand. And that's why I'm here today.

So, my reason for coming here isn't to find a solution to a problem, per se. It's to find an answer to a question. And for some of you pros, the question might seem awfully silly.

Alright, so here we go. I have recently been recording with two specific microphones: My Blue Yeti (not a Pro) USB microphone and a Shure SM58 connected to a Focusrite Scarlett Solo USB audio interface. (Told ya I'm new!)

My question has to do with the specifications of the two microphones. I understand their specs will be much different, due to the fact that one is a stereo condenser USB microphone (Blue Yeti) and the other is a mono dynamic XLR microphone (Shure SM58).

Upon many recording experiments, my comparison of the two yielded that the Blue Yeti was giving me better results than the Shure SM58. Strange, right?

When recording with the Shure SM58, my interface has to cranked to the highest gain setting for there to be any hope of capturing an audible signal. (Seeing as the Gain Range for the "Scarlett Solo's Microphone Input" is from -4 dB to +46 dB, I have the interface set to +46 dB in this case.) Even then I have to normalize the audio afterwards, resulting in unwanted white noise. I do not have this problem with the Blue Yeti. Even when my Yeti's gain is all the way down (no signal boost), it picks up a nice, meaty signal.

Using GoldWave, a digital audio editor, I noticed something strange with the gain strengths of my Scarlett Solo interface vs my Blue Yeti. I've attached a picture showing my observations.



Notice the color of the Volume (dB) bar and the numbers to the right.



For the Blue Yeti, the number to the right (not sure if it's called the Gain Boost or not) is up to 3548.13%! The bar is red, meaning it can record such a high level of signal that the channel can become hot and therefore distort the signal.

Yet, for the Scarlett Solo, notice that the color of the Volume (dB) bar is green (signifying a quiet signal) and the number to the right is a mere 100% (which I'm assuming means no Gain Boost or "none of something" for whatever that number may signify; it's the default level).

So my question is... What gives?

Everything is probably fine; perhaps this is the way the interface is designed to function, and for good reason. Yet it still seems strange to me that the Blue Yeti has so much more capability (or so I believe) for capturing signal than the interface I'm using.

Thank you for any help provided in the future!

 

[4tracker]

Make sure the Shure microphone is routed properly through the focusrite and you aren't metering the built-in/onboard PC mic. Make sure to unplug the Yeti while the other one is plugged in. Some dymamic mics can be quiet and require more gain (like a cloudlifter or fethead) in between. I'm not sure about the SM58, but my ribbons require that otherwise the gain is low. The problem could be something else, though. But check all that.

 

[miroslav]

You're using Line In on one and Mic In on the other... the Mic In will be more sensitive.
Also...you have mic/interface on one...and USB direct on the other...so you may not be staging the gain equally and relatively to make a direct comparison between them.

Your Scarlett should have its own Mic gain....and separate Line out...so fist adjust the Mic In to get a nice solid signal going into the Scarlett and then adjust the output to get a good signal into the computer.

With the USB mic...you're just adjusting in the computer.

(If I understood your process correctly)

 

[CMolena]

The Blue Yeti is a condenser mic, so it naturally has more gain than the SM58 which is a dynamic one (and a quiet dynamic one, if I may put it like that)

That aligned with the fact that the Yeti is connected via USB, make the gain go up high, because the only connection you have between the mic and the capture device is a USB cable (maybe the Blue Yeti has some internal circuitry that could reduce the signal without losing quality, but IDK). If you could pick up another condenser and plug it into your interface you would see that the gain will be much more controlled.

The interface has preamps and proper D/A converters that will make the signal ideal for recording purposes in a PC or Mac, or any digital recording medium. So the noise will be significantly lower without losing the quality of the signal.

 

[ecc83]

Fork me! It is confusing enough when we are talking about just mic sensitivities and electronic's "gain"!

Put USB mics into the mix and Gaaaahhh!

Yes, that Solo has much lower gain* than is going to be useful with a 57/58 (and a claimed EIN of a poorish 125dB. But then, noise speccs are ALWAYS SUS!) The AI seems to use ASIO drivers and so will be its own "thing" as far as the computer is concerned but often this can be changed in the DAW.

The Yeti being USB is totally at the mercy of the OS for setting gain. (but ASIO4all might help there?)

My NI KA6 also needs the gain flat out for acoustic guitar at about a foot from a 57 (ok! SON likes it!) but the pres are low enough noise to give me about a -70dBFS noise floor which is mostly "room" noise, even at 3am. The mic then gives around -20dBFS.

^ "Gain" of a mic input on an AI is a pretty silly specc! What we really need is INPUT SENSITIVITY in mV or dBu or both for a GIVEN level in dBFS in the DAW.

As it stands a figure of "46dB" means nothing. Does that produce 0dBFS for the 1.6mV output of a 58? (No! nowhere near!) or +4dB out of the line outs? Neg ten mayhap?

And! (said it before) I can never see the point of ONE mic input for MOOOSIC!

Dave.

 

[Bobbsy]

Upon many recording experiments, my comparison of the two yielded that the Blue Yeti was giving me better results than the Shure SM58. Strange, right?

Others have gone into a lot more detail but let me just say that there's nothing strange about your Yeti outperforming an SM58 in a home studio.

The SM58 is designed for live use on a stage with lots of loud sound going on around it. It's strength is rejecting sounds other than a mouth singing or yelling loudly an inch or two away and not giving too much feedback when amplified. However, sensitivity and sound quality are not its strong points and frequently you DO have to crank you input pre amp up into a range where any noise will become apparent.

The Yeti, on the other hand, is designed for recording use in a studio. It's quite a bit more sensitive and also offers a flatter frequency response especially at upper frequencies. It's far from the best condenser around...but it's designed for the sort of thing you're doing, not live work on a stage. Indeed, in some situations, the sensitivity will be a problem if you start to pick up lots of background noise from the room.

 

[VectorPeasley]

Make sure the Shure microphone is routed properly through the focusrite and you aren't metering the built-in/onboard PC mic.

How exactly would I do that? That is, checking to see if the mic is "routed properly?" I'm not yet familiar with that specific term.

You're using Line In on one and Mic In on the other... the Mic In will be more sensitive.
Also...you have mic/interface on one...and USB direct on the other...so you may not be staging the gain equally and relatively to make a direct comparison between them.

Your Scarlett should have its own Mic gain....and separate Line out...so fist adjust the Mic In to get a nice solid signal going into the Scarlett and then adjust the output to get a good signal into the computer.

With the USB mic...you're just adjusting in the computer.

(If I understood your process correctly)

Again, I'm not familiar with the difference between "Line-In" vs "Mic-In." I'm assuming you mean that Line-In means connected via some interface/mic setup, such as with an XLR cable, whereas Mic-In means connected directly to the computer, in this case, via USB.

I skimmed your post (too early in the morning to read and comprehend yet ). I think this may be what you're looking for(?)

The Yeti has almost 2.5 times the signal output of the SM58 for the same audio pressure level at its diaphragm. It's somewhat typical for a condenser mic to have a "hotter" output than a dynamic type of mic.

Shure SM58 sensitivity
Cardioid (1.85 mV/Pa; 50 - 15,000 Hz)

Blue Yeti sensitivity
Omnidirectional (4.5 mV/Pa; 180 - 20,000 Hz)
Cardioid (4.5 mV/Pa; 150 - 15,000 Hz)
Bidirectional (4.5 mV/Pa; 100 - 15,000 Hz)
X/Y Stereo (4.5 mV/Pa; 80 - 15,000 Hz)


Understand Microphone Sensitivity Specifications

Very informative! Looks like I have another good read to add to my list!

Yes, that Solo has much lower gain* than is going to be useful with a 57/58 (and a claimed EIN of a poorish 125dB. But then, noise speccs are ALWAYS SUS!)

My NI KA6 also needs the gain flat out for acoustic guitar at about a foot from a 57 (ok! SON likes it!) but the pres are low enough noise to give me about a -70dBFS noise floor which is mostly "room" noise, even at 3am. The mic then gives around -20dBFS.

Interesting. I might be reaching a bit too far here, but based on your response, specifically the words, "... that Solo has much lower gain than is going to be useful with a 57/58," would you recommend that I buy a better interface with more gain / a better preamp?

The Blue Yeti is a condenser mic, so it naturally has more gain than the SM58 which is a dynamic one (and a quiet dynamic one, if I may put it like that)

It sure is quiet. I was told that the Shure SM58 was ideal for vocal recordings, but it's just so darn quiet that I have to crank up the dBs just to hear myself. That, or crank the gain up on the interface so high that every recording is in danger of easily distorting.

... There's nothing strange about your Yeti outperforming an SM58 in a home studio.

Sadly, every review, every video, and every comment I can possibly find online has said otherwise. And yet, from my recent experiences with the Shure SM58/Focusrite Scarlett Solo setup, I actually agree with you, Bobbsy.


My main concern behind my initial query is that I'm trying to capture the best possible sound quality for the sake of voice acting. Research has told me that dynamic microphones are best for vocal performances. But the more I look into it--and the more condenser microphones I test--the better results I'm getting from the condenser microphones. My next mic may be a AT2020 or AT2035, seeing as it is a side-address XLR condenser mic with a large diaphragm. I'm trying to get as much vocal quality as I possibly can capture for rich, clear, clean, and loud vocals with minimal white noise. Perhaps I should look into a better interface... or some hardware that will run between the mic and the interface to increase the signal's gain. Seeing as the Shure SM58 is a naturally quiet mic with excellent off-axis rejection, perhaps I need either a more sensitive mic or a better interface?

 

[Bobbsy]

I'm curious who told you the SM58 was "ideal for vocal recordings"?

As I said above, the SM58 isn't designed for recording at all. It's a mic primarily for live work on a stage where the ability to handle loud material while rejecting background stage wash is important. For recording? Well, it can be used but that's not what it's for.

There ARE dynamic mics commonly used for voice recording/voice acting but they tend to be rather more expensive than the SM58. Have a Google for mics like the Electrovoice RE20 or the Shure SM7B. Even so, given a properly treated room you'll probably see more large diaphragn condensers in use for voice recording. The strength of the large dynamics is their ability to reject room noise in places not so well treated.

Anyhow, while the SM58 is a popular mic in the live sound community--and sometimes used in studios by screaming heavy metal singers, you've been given some pretty duff information about what's ideal.

 

[John Willett]

Again, I'm not familiar with the difference between "Line-In" vs "Mic-In." I'm assuming you mean that Line-In means connected via some interface/mic setup, such as with an XLR cable, whereas Mic-In means connected directly to the computer, in this case, via USB.

"Line in" is a line level signal from a pre-amplifier or similar device. This would be the output from an analogue mixer, mic. pre-amplifier, output from a recorder, or any devise that outputs "line level".

"Mic. in" is the low level output from any analogue microphone - so, the cable from the microphone is plugged into "mic. in" - if you have a condenser mic. you will, most likely, need to have "phantom power" switched on (unless it has an internal battery).

You *never* connect a computer to "mic. in" and definily *not* by USB.

The computer USB is best used for connection to an audio interface (eg" RME Babyface Pro, Focusrite Scarlett series, and the like) and it's these interfaces that have the "line in" and "mic in" connections.

 

[John Willett]

I'm curious who told you the SM58 was "ideal for vocal recordings"?

As I said above, the SM58 isn't designed for recording at all. It's a mic primarily for live work on a stage where the ability to handle loud material while rejecting background stage wash is important. For recording? Well, it can be used but that's not what it's for.

There ARE dynamic mics commonly used for voice recording/voice acting but they tend to be rather more expensive than the SM58. Have a Google for mics like the Electrovoice RE20 or the Shure SM7B. Even so, given a properly treated room you'll probably see more large diaphragn condensers in use for voice recording. The strength of the large dynamics is their ability to reject room noise in places not so well treated.

Anyhow, while the SM58 is a popular mic in the live sound community--and sometimes used in studios by screaming heavy metal singers, you've been given some pretty duff information about what's ideal.

Yup - I agree with all this - well said.

 

[ecc83]

"Interesting. I might be reaching a bit too far here, but based on your response, specifically the words, "... that Solo has much lower gain than is going to be useful with a 57/58," would you recommend that I buy a better interface with more gain / a better preamp?"

Yes! And not just for increased gain but also for two mic inputs, anyone interested in recording will surely want to dabble with stereo at some point? The Steinberg UR22 has always been praised for its "clean" mic pres, a term I take to mean low noise? Gain, i.e. a lot of it, means nothing if the noise gets worse!

At 4.5mV/Pa the Yeti is on the low side for a large D capacitor? Most are around 20dB better than a 57/58. Could be a by product of building a multipattern microphone at a budget price? I don't know enough about the technology.

I totally agree with all that has been said about dynamics not being really suited to voice recording but I would like to clear up one possible misunderstanding/myth?

The operational method of a microphone capacitor. moving coil. ribbon, cannot of itself affect the mic's ability to "reject" ambient noise. The ratio of wanted to unwanted sound is primarily determined by your proximity to the diaphragm. The closer you get, the less gain you need and therefore the less "room" you will pick up. In fact a very good compromise for the impecunious home recordist is a Small D Cap mic with a 20dB pad.

Dave.

 

[ecc83]

Ah! Did not see that the Yeti was an SDC Mark!

Yup, about right then.

Dave.

 

[VectorPeasley]

I'm curious who told you the SM58 was "ideal for vocal recordings"?

As I said above, the SM58 isn't designed for recording at all. It's a mic primarily for live work on a stage where the ability to handle loud material while rejecting background stage wash is important. For recording? Well, it can be used but that's not what it's for.

Anyhow, while the SM58 is a popular mic in the live sound community--and sometimes used in studios by screaming heavy metal singers, you've been given some pretty duff information about what's ideal.

While I was doing research for "Best Vocal Mic for Home Studio," websites everywhere, such as the one below, consistently recommended the Shure SM58.

7 Best Microphones for Recording Vocals: under $700
31 of the best microphones for recording vocals | MusicRadar
10 Best Affordable Microphones for the Home Studio - Tuts+ Music & Audio Tutorial

Although, upon further inspection, these websites may have been claiming that the Shure SM58 was one of the best vocal performance mic, such as for singing, preaching, giving a speech or presentation, etc--not the best vocal recording mic. If so, I understand my confusion.

Notice that this website (The Top 10 Best Microphones for Recording Vocals - The Wire Realm) does not list the Shure SM57/58 microphones. Maybe they're onto something?

"Line in" is a line level signal from a pre-amplifier or similar device. This would be the output from an analogue mixer, mic. pre-amplifier, output from a recorder, or any devise that outputs "line level".

"Mic. in" is the low level output from any analogue microphone - so, the cable from the microphone is plugged into "mic. in" - if you have a condenser mic. you will, most likely, need to have "phantom power" switched on (unless it has an internal battery).

You *never* connect a computer to "mic. in" and definily *not* by USB.

The computer USB is best used for connection to an audio interface (eg" RME Babyface Pro, Focusrite Scarlett series, and the like) and it's these interfaces that have the "line in" and "mic in" connections.

Seems that I have alot to learn. Thank you for taking the time to explain!

"Interesting. I might be reaching a bit too far here, but based on your response, specifically the words, "... that Solo has much lower gain than is going to be useful with a 57/58," would you recommend that I buy a better interface with more gain / a better preamp?"

Yes! And not just for increased gain but also for two mic inputs, anyone interested in recording will surely want to dabble with stereo at some point? The Steinberg UR22 has always been praised for its "clean" mic pres, a term I take to mean low noise? Gain, i.e. a lot of it, means nothing if the noise gets worse!

Dave.

Thank you for the conformation! Do you have any other recommendations for better interfaces (preferably ones that have, as you mentioned, "clean" mic preamps)?

The Yeti is an SDC with 14mm diaphragm diameter capsules > Blue Microphones Yeti | RecordingHacks.com
4.5mV/Pa is on par with most of the SDC's I have. My hottest mics appear to be Audio Technica's (AT4040 & AT3035) that are about 25mV/Pa. Also a renegade, LDC looking AT4033 with a 11.5 mm diaphragm diameter which is smaller than most of my SDC's as well at about 25mV/Pa.

Oh! New terminology.
SDC = Small Diaphragm Condenser mic
LDC = Large Diaphragm Condenser mic

Out of curiosity, which type of the above is more suited for voice acting/vocal recording? I already have a general idea as to which one is better suited for vocal recording--as Bobbsy said, "given a properly treated room you'll probably see more large diaphragn condensers in use for voice recording. The strength of the large dynamics is their ability to reject room noise in places not so well treated."
Of course, which type of mic to use depends entirely on the vocalist's speech type, the recording environment, and the intended purpose of the recording.

Also, thanks for yet another great resource! RecordingHacks.com looks like the bomb.

 

[Bobbsy]

Hmmm...I had fun looking at those links and I daresay this is a good example of why you need to be very careful of anonymous advice from the internet.

All those three first links that include the SM58 on their "Top X Recordable mics list" seem to recommend the mic in the headline then, in the body of the text, extol the SM58's virtues in a LIVE situation and go onto say that it can be useful in a studio "on certain material". In some places they go into detail about how it works well on loud singers or people who like to hold the mic in the studio. I've got no problem with any of the qualified statements but the headlines are very misleading.

FYI, the very last time I recorded a voice I did use an SM58. I needed a voice over for use in a live theatre situation and the only way I could do it was drag my recording set up to the theatre--the actor couldn't schedule a visit to my studio. In a relatively noise environment without acoustic treatment, it was an obvious choice. However, note that I used an interface with a mic pre I knew could handle being turned up without bad noise..and had an actor who was supposed to be shouting for the lines anyway. It wouldn't have worked nearly so well for subtle, quietly-spoken voice acting.

Anyhow, this all started with a question about why IN YOUR SITUATION your Yeti sounds better than the "best mic for home studio vocals" so I think you've proven to yourself that you needed to read the fine print in those guides and reviews. Yes, the 57 and 58 would both be on my list of mics a studio needs...but a first mic where the application is voice acting, not singing? Nope. Not even in my top ten.

But then I'm giving anonymous advice on the internet! Doh!

 

[Bobbsy]

Oh! New terminology.
SDC = Small Diaphragm Condenser mic
LDC = Large Diaphragm Condenser mic

Out of curiosity, which type of the above is more suited for voice acting/vocal recording? I already have a general idea as to which one is better suited for vocal recording--as Bobbsy said, "given a properly treated room you'll probably see more large diaphragn condensers in use for voice recording. The strength of the large dynamics is their ability to reject room noise in places not so well treated."
Of course, which type of mic to use depends entirely on the vocalist's speech type, the recording environment, and the intended purpose of the recording.

Also, thanks for yet another great resource! RecordingHacks.com looks like the bomb.

If you're genuinely doing voice acting, I'd go with an LDC (Large Diaphragm Condenser). I'd fit it with a pop screen and, for voice work you want a "dead" studio so I'd put soft absorbent stuff behind and beside the person speaking. There's a whole sub forum here about how to acoustically treat a room but remember...for music you want a room to sound good. For voice work you want no room tone at all--you need to be able to blend your voice in with whatever else is going one, whether it's background music or sound effects putting you in a war zone or something.

If you have room problems I'd seriously look at the sE Reflexion Filter. Not cheap but it works well. I once did a whole book reading for a fairly well known author sitting in her study because health issues meant she couldn't get to the studio. With the Reflexion Filter it sounded okay.

As for which mic, it depends on budget. The AT2020 and the Rode NT1A both have good reputations. For a bit more money, the sE X1 or the sE2200A are better and better again. When you're rich and famous, look at Neumann stuff.

Before I retired I did a lot of voice recording in professional studios and we'd choose the mic based on a mix of the voice and material (and, as per my anecdotes above, the location of the recording). We used a mix of stuff but the vast majority--maybe 80%--was on large condensers of various brands with the remaining 20% done on all sorts of weird and wonderful stuff, from dynamics to even a short shotgun for a guy who needed the typical movie trailer extra bass voice.