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What's the deal with microphones?

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I want to record some voice-over stuff, and I have an inexpensive condenser mic. I was not really happy with the sound I was getting, so I started doing some EQ and looking at other microphones that people rave about...and I just don't understand what they're talking about.

Can someone address the following questions?

1. When people talk about how microphones sound, are they really not applying EQ? Like, if they say a microphone is light in the bass...that means they aren't boosting the bass? Doesn't EQ account for 90% of a microphone's sound?

2. I have a dynamic mic and some mini type condensers, and it seems to me that the source proximity and proportion of room noise is vastly more important than the actual microphone. My dynamic is an SM58, and while the sound is a bit grainy, the added room rejection compared to my large diaphragm condenser makes it sound better in practice. Am I crazy? After EQ, the condenser sounded great except for a bit of the room slap.

3. Adding on to the room-rejection, this is caused by the directivity of the microphone - shouldn't the directivity basically be identical between different diaphragm sizes/types? Like shouldn't all cardioid 1" units have the same basic pattern?

4. It seems to me that the most useful application for expensive, beautiful sounding mics would be where EQ and other processing is impractical, like a live radio show, but people use them in recording studios where everything is processed anyway? What's up with that?

5. My large diaphragm condenser has a sort of pleasant thickness to it, and produces a nice loud signal, but my tiny instrument type omni condensers (made by Niaint) and my speaker measurement microphone sound far truer to life. Does anyone use small diaphragm condensors for voice or are they using the microphone as an effect unit?

Any input into this world would be helpful. The consumer in me feels the need to buy something fancy but it seems like room treatments would be a better investment.
 

Inner Space

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A microphone is the functional opposite of a loudspeaker, so I think many of your questions are answered simply by substituting one word for the other. E.g. the directivity of the loudspeaker - shouldn't the directivity basically be identical between different diaphragm sizes/types? It's the same world in reverse. Your last sentence is the most important, though. Room treatment is vital - for voiceover work I would use a vocal booth.
 

mixsit

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I want to record some voice-over stuff, and I have an inexpensive condenser mic. I was not really happy with the sound I was getting, so I started doing some EQ and looking at other microphones that people rave about...and I just don't understand what they're talking about.

Can someone address the following questions?

1. When people talk about how microphones sound, are they really not applying EQ? Like, if they say a microphone is light in the bass...that means they aren't boosting the bass?
Doesn't EQ account for 90% of a microphone's sound?
Your meaning is unclear. Different mics have different freq responses. If tour meaning here is 'picking a mic for its freq tone balance, then yes the choice is like making a preferred eq'd choice.
But if a mic is 'lite in the lows- it is what it is. We then may decide to add lows. Is that what you mean?

2. I have a dynamic mic and some mini type condensers, and it seems to me that the source proximity and proportion of room noise is vastly more important than the actual microphone. My dynamic is an SM58, and while the sound is a bit grainy, the added room rejection compared to my large diaphragm condenser makes it sound better in practice. Am I crazy? After EQ, the condenser sounded great except for a bit of the room slap.
Things in play here; -Working distance -closer (usually) means more lows (proximity effect on directional mics), and less 'room bleed. Mics like the sm58 meant to be used close' have reduced low end built in to compensate. Most large dia condensers do not, and will give much more lows at equal distance as the 58, but then would give similar room rejection (assuming both cardioid pattern)
3. Adding on to the room-rejection, this is caused by the directivity of the microphone - shouldn't the directivity basically be identical between different diaphragm sizes/types? Like shouldn't all cardioid 1" units have the same basic pattern?
Not at all. Many do omni/cardi/fig-8 switchable in one. (omni has almost no proximity effect, fig-8 has even more then cardi.)
4. It seems to me that the most useful application for expensive, beautiful sounding mics would be where EQ and other processing is impractical, like a live radio show, but people use them in recording studios where everything is processed anyway? What's up with that?

5. My large diaphragm condenser has a sort of pleasant thickness to it, and produces a nice loud signal, but my tiny instrument type omni condensers (made by Niaint) and my speaker measurement microphone sound far truer to life. Does anyone use small diaphragm condensors for voice or are they using the microphone as an effect unit?
I happen to like, and think omni's are wonderful options to have around. (Early on an experience with my Earthworks QTC-1 on a fiddle player 'cemented this in my brain. Totally love how -unlike mics in general, how natural and real the playback!
Any input into this world would be helpful. The consumer in me feels the need to buy something fancy but it seems like room treatments would be a better investment.
 

earlevel

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Small diaphragm condenser are fine for overhead mic for drums, higher-frequency instruments. For voice you need a large diaphragm condenser, or a good dynamic.

You could get a less expensive dynamic (SM58 at $99 is the vocal mic of many rock vocal icons), but the reason $30M/yr podcasters like Joe Rogan use SM7B is that it's not exciting but it's flat, and also pretty directional and (doesn't pic up a lot of other garbage). SM7B needs a strong preamp or a booster (Cloudlifter).

If you're doing VO, you're probably recording in a more controlled setting (like, just you in the room), and a large diaphragm condenser is a good choice. Not small, you need low end extension. Unlike the early '90s when the only useable LDCs were made in Germany or Austria and the price of admission was $1k to start (but I still have my AKG C414B-ULS from then). Condensers give you crispness over dynamics. For the single voice of VO, I'd think that is good for focus. Luckily, we're in the golden age of condensers and there are good ones at all price points. Gearspace, youtube demos/reviews, comb them. Or spend more for the solid classic you can't go wrong with.

So, why not EQ...there is a vast difference between subtle flavor tweaks (a little upper-mid boost for clarity of the words, roll off a little bass) and trying to fix a poor frequency response. The only reason a mic will have poor frequency response (largely) is that it's a poor mic, they didn't try hard enough. (Or possible it's a good mic that is widely used for a frequency range that doesn't suit voice especially well, but I'm generalizing). Now, if it isn't that good, why expect it to be flat? You could get one that seems surprisingly good for $50, and sound nearly like what you want it to sound like. You might think, I'll just tweak the mids a bit, boost some of the 10k air and it'll be fine. But, if it's peaky up there, like a picket fence, you might find that you can't balance the mids like you want without nearby frequencies getting screechy. And if you back off, you loose clarity.

Your safest bet is to get something that sounds smooth and fairly flat. Then make subtle changes. You can have two great mics that are flat throughout the voice range within 2 dB, and they can sound quit different, just depends where the highest and lowest points sit. Best to try them and go with what works for you. But if you really don't know yet and need work with such a mic and gain experience, go with a popular choice that you hear samples of other people using and sounding great to you.
 
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Small diaphragm condenser are fine for overhead mic for drums, higher-frequency instruments. For voice you need a large diaphragm condenser, or a good dynamic.

You could get a less expensive dynamic (SM58 at $99 is the vocal mic of many rock vocal icons), but the reason $30M/yr podcasters like Joe Rogan use SM7B is that it's not exciting but it's flat, and also pretty directional and (doesn't pic up a lot of other garbage). SM7B needs a strong preamp or a booster (Cloudlifter).

If you're doing VO, you're probably recording in a more controlled setting (like, just you in the room), and a large diaphragm condenser is a good choice. Not small, you need low end extension. Unlike the early '90s when the only useable LDCs were made in Germany or Austria and the price of admission was $1k to start (but I still have my AKG C414B-ULS from then). Condensers give you crispness over dynamics. For the single voice of VO, I'd think that is good for focus. Luckily, we're in the golden age of condensers and there are good ones at all price points. Gearspace, youtube demos/reviews, comb them. Or spend more for the solid classic you can't go wrong with.

So, why not EQ...there is a vast difference between subtle flavor tweaks (a little upper-mid boost for clarity of the words, roll off a little bass) and trying to fix a poor frequency response. The only reason a mic will have poor frequency response (largely) is that it's a poor mic, they didn't try hard enough. (Or possible it's a good mic that is widely used for a frequency range that doesn't suit voice especially well, but I'm generalizing). Now, if it isn't that good, why expect it to be flat? You could get one that seems surprisingly good for $50, and sound nearly like what you want it to sound like. You might think, I'll just tweak the mids a bit, boost some of the 10k air and it'll be fine. But, if it's peaky up there, like a picket fence, you might find that you can't balance the mids like you want without nearby frequencies getting screechy. And if you back off, you loose clarity.

Your safest bet is to get something that sounds smooth and fairly flat. Then make subtle changes. You can have two great mics that are flat throughout the voice range within 2 dB, and they can sound quit different, just depends where the highest and lowest points sit. Best to try them and go with what works for you. But if you really don't know yet and need work with such a mic and gain experience, go with a popular choice that you hear samples of other people using and sounding great to you.

Do you know of any resources for high resolution FR charts for mics? The ones published by manufacturers are all incredibly smooth and don't look realistic.

For example, looking at the axial FR for a Shure KSM 24, it shows a slight bass and presence boost, both around 3db and very smooth. Is that realistic or is just communicating the basic character of the mic?

If what you say is true, and eq can't fix a mic easily, that implies that the mic is fairly nonlinear, but it looks like most large condensers are flat to around 5k and even then very well behaved compared to a speaker. I can't find a mic FR that has any high Q resonances, although I guess they could occur off axis.

My bigger condenser, for example, is a Samson c01:
C01Freq.png


Coming from the world of a speaker designer....that thing is pretty dang flat, but I'm seeing something I don't understand: the huge treble boost at 180 degrees. This is a super cardioid unit, does that have anything to do with this?

Again, it seems like the axial response of a mic is really well behaved though, so it leads me to believe controlling the sound field through positioning and room dampening is probably more significant than mic choice.
 
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I've also been experimenting with vsts for voice and I've been delighted by some of them. The waves de esser is awesome, and I found a loudness maximizer and lufs calculator which work really well too. I all have a noise filter and breath deleter. It just seems like the mic is a small although admittedly sexy part of the equation.
 

Blumlein 88

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Do you know of any resources for high resolution FR charts for mics? The ones published by manufacturers are all incredibly smooth and don't look realistic.

For example, looking at the axial FR for a Shure KSM 24, it shows a slight bass and presence boost, both around 3db and very smooth. Is that realistic or is just communicating the basic character of the mic?

If what you say is true, and eq can't fix a mic easily, that implies that the mic is fairly nonlinear, but it looks like most large condensers are flat to around 5k and even then very well behaved compared to a speaker. I can't find a mic FR that has any high Q resonances, although I guess they could occur off axis.

My bigger condenser, for example, is a Samson c01:
View attachment 147398

Coming from the world of a speaker designer....that thing is pretty dang flat, but I'm seeing something I don't understand: the huge treble boost at 180 degrees. This is a super cardioid unit, does that have anything to do with this?

Again, it seems like the axial response of a mic is really well behaved though, so it leads me to believe controlling the sound field through positioning and room dampening is probably more significant than mic choice.
I thought the same thing. I now believe those curves are reasonably accurate. I've used cal files created from those low rez graphs for several microphones. Apply them to the mikes, and then compare the result of sweeping a given speaker vs a calibrated Umik-1. They pretty much just lay on top of each other if they are omnis. They come close to that if other types other than in the lower 200 hz range.
 

goat76

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Do you know of any resources for high resolution FR charts for mics? The ones published by manufacturers are all incredibly smooth and don't look realistic.

For example, looking at the axial FR for a Shure KSM 24, it shows a slight bass and presence boost, both around 3db and very smooth. Is that realistic or is just communicating the basic character of the mic?

If what you say is true, and eq can't fix a mic easily, that implies that the mic is fairly nonlinear, but it looks like most large condensers are flat to around 5k and even then very well behaved compared to a speaker. I can't find a mic FR that has any high Q resonances, although I guess they could occur off axis.

My bigger condenser, for example, is a Samson c01:
View attachment 147398

Coming from the world of a speaker designer....that thing is pretty dang flat, but I'm seeing something I don't understand: the huge treble boost at 180 degrees. This is a super cardioid unit, does that have anything to do with this?

Again, it seems like the axial response of a mic is really well behaved though, so it leads me to believe controlling the sound field through positioning and room dampening is probably more significant than mic choice.

Don't get me wrong, but I think you're thinking way too much in terms of what would be important for measuring speakers. If the microphone is meant to be used for recording your own voice, there's nothing wrong with something that will give you the right amount of character, something that will enhance your voice to your liking and maybe sound close to the way you hear your own voice when you speak. A ruler flat response is not very important for this.

I have a bunch of microphones I use for my own music recordings that all works well for recording vocals like the Electro Voice RE20, an Audio Technica AT4033, the Warm Audio WA-47jr and a Cascade Fat Head II. The one that suits my voice the best for singing is the 47jr.
For just recording speach the RE20 works really well, but you probably need a Cloudlifter or a Triton Audio FetHead because it's not very sensitive.

Here you can hear the RE20 in action, both for speach and some beautiful singing voice. :)

 

SIY

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Yes, I understand there are noise and distortion characteristics.

A lot more than that. Think about cases, mounts, venting... all strongly affect the polar and frequency responses.
 

Chromatischism

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If you're doing VO, you're probably recording in a more controlled setting (like, just you in the room), and a large diaphragm condenser is a good choice. Not small, you need low end extension.
So my UMIK-1 is flat to 20 Hz. Why isn't it a good voice mic?
 

Chromatischism

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The UMIK-1 is quite noisy and I wouldn't use it unless I had no other choice.
I currently don't, but I'm open to finding a dedicated mic for the PC so I can leave my UMIK alone.
 

Trell

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I currently don't, but I'm open to finding a dedicated mic for the PC so I can leave my UMIK alone.

The UMIK-1 is also omnidirectional which can give issues when used for voice in a room. If you already have an audio interface you have a much wider selection of mics to choose from than just USB mics, and generally of much better quality.
 

Trell

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Small diaphragm condenser are fine for overhead mic for drums, higher-frequency instruments. For voice you need a large diaphragm condenser, or a good dynamic.

You could get a less expensive dynamic (SM58 at $99 is the vocal mic of many rock vocal icons), but the reason $30M/yr podcasters like Joe Rogan use SM7B is that it's not exciting but it's flat, and also pretty directional and (doesn't pic up a lot of other garbage). SM7B needs a strong preamp or a booster (Cloudlifter).

If you're doing VO, you're probably recording in a more controlled setting (like, just you in the room), and a large diaphragm condenser is a good choice. Not small, you need low end extension. Unlike the early '90s when the only useable LDCs were made in Germany or Austria and the price of admission was $1k to start (but I still have my AKG C414B-ULS from then). Condensers give you crispness over dynamics. For the single voice of VO, I'd think that is good for focus. Luckily, we're in the golden age of condensers and there are good ones at all price points. Gearspace, youtube demos/reviews, comb them. Or spend more for the solid classic you can't go wrong with.

So, why not EQ...there is a vast difference between subtle flavor tweaks (a little upper-mid boost for clarity of the words, roll off a little bass) and trying to fix a poor frequency response. The only reason a mic will have poor frequency response (largely) is that it's a poor mic, they didn't try hard enough. (Or possible it's a good mic that is widely used for a frequency range that doesn't suit voice especially well, but I'm generalizing). Now, if it isn't that good, why expect it to be flat? You could get one that seems surprisingly good for $50, and sound nearly like what you want it to sound like. You might think, I'll just tweak the mids a bit, boost some of the 10k air and it'll be fine. But, if it's peaky up there, like a picket fence, you might find that you can't balance the mids like you want without nearby frequencies getting screechy. And if you back off, you loose clarity.

Your safest bet is to get something that sounds smooth and fairly flat. Then make subtle changes. You can have two great mics that are flat throughout the voice range within 2 dB, and they can sound quit different, just depends where the highest and lowest points sit. Best to try them and go with what works for you. But if you really don't know yet and need work with such a mic and gain experience, go with a popular choice that you hear samples of other people using and sounding great to you.

There are very fine small diaphragm condenser to be had for voice work, like the Earthworks Audio SR314.
 

Blumlein 88

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So my UMIK-1 is flat to 20 Hz. Why isn't it a good voice mic?
Because a flat microphone doesn't flatter your voice. There likely are voices that would sound good on the Umik with a good room.

With cardioid, you can also play with how far away you sing into it to alter the 200 hz and below response. Up close the bass is extra full, and from 2 or 3 feet away the bass is lean. As SIY is pointing out you have other things involved. Various membranes may have resonances which effect response and directionality. The back side of the diaphragms are loaded in a few different ways which can make small differences. The head basket may shade the diaphragm in some directions. Also in condensers you need to pay some attention to shielding so you don't get RF pickup.

Then you have ribbon microphones. A whole different animal.
 

earlevel

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So my UMIK-1 is flat to 20 Hz. Why isn't it a good voice mic?

"20 Hz - 20kHz +/-1dB with calibration loaded"—first would you be using it calibrated? Probably not, if you plug in and record.

But it's back to what I said before. You can be flat ±1 dB, and it all depends where the wiggles are (and other things). Even if it were calibrated, I'm sure my AKG C414B-ULS is goin to sound a lot better. Second, there are other aspects such as directionality. A speaker calibration mic only needs to measure a loud pure tone at a fixed level—it just needs to give a consistent level at any frequency for that tone, or have a calibration file to adjust for how far it's off. I've seen a raw frequency response chart for the UMIK-1 before, I don't know whether it was representative, but it wasn't flat. DOn't forget, there is a proximity effect too, for cardioids, some leverage that.

Anyway, I gave general tips, I'm not defining what you should use. Bono and Brandon Flowers use an SM58, others use mics that cost 100 times more.

I don't know voice over, but I've been in threads with with pro VO people who say what they use, and give samples. Neumann U87 (currently U87AI, ~$3.2k). Some are using the mic I got recently, Soyuz 017 FET ($2k). The U87 is a nice mic, but rented one and a C414 thirty years ago to compare, bought the C414 (both were good, the AKG was cheaper). Both sound good for talking, to me, but the Soyuz is in another world, at least on my voice. I don't even like my voice (common), but I could listen to me talk for hours on the FET. :p

Anyway, like I said, the safest is to get something fairly flat and smooth. Then you can EQ it. There are also the virtual mics. Obviously, they have to be reasonably smooth/flat to start with, so you can convolve with the impulse responses of the difference with the mics it emulates. If you have the bucks, you can pick an emulation that helps you sound great. Quite a range of prices, but the slate isn't too high and I think has affordable packages (so they can sell you more IRs), there is another even cheaper that I can't think of at the moment, but just do a search on vitual microphones and comparisons.

I have another thing I'll save for another post...
 
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earlevel

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Again, I'm more familiar with recording singing. I've done a few youtube videos, so I do pay some attention to trying to sound good doing dialog, but I'm a total amateur there.

But, there is a mic, first. Then there is recording environment (some mics are very sensitive, and/or sound best when you backed off a bit—you don't not what the sound of poor room making you expensive mic sound like you are trapped in a cardboard box. So, you can get an environmentally forgiving mic like the SM7B (dynamic but flat) or, put up from some sound absorption traps (not expensive to make your own, check youtube).

Then there is also the preamp. If you've got a decent mic pre in a USB interface or whatever, it's probably good enough (unless you have a mic like the SM7B that needs an unusual amount of gain), but you at least want to make sure it doesn't suck.

Then, you'll want some compression and/or limiting (they're related). You need that steady volume if you want to sound professional. It could be in a plugin, or external. And you can have preamps that add beef, in either plug-in or external hardware form. Most of the preamp emulations sound pretty unimpressive to me, but there are some that sound good. Plugin compressors do the job well, but may not add the heft of external gear.

The external stuff can be quite expensive, but make you sound like a god. I want to sound like a god, but not drain my bank account, so I recently got a Klark Teknik (aka Music Tribe aka Behringer) 76-KT and EQP-KT. These are cheap ($299 and $249) clones of classic must-have gear (1176 compressor/limter and Pultec EQ, at a small fraction of the price. I'm waiting on the 2A-KT (LA-2A clone), backordered production. One advantage of external gear is that there is zero latency, so you sound like a god on headphones as you are recording, instead of recording meh and making it sound like a god in post processing. (Some digital interfaces allow for extremely low latency, so not impossible to get there with plugins.) While some may argue how close the KT's are to the originals, there are quite clean and effective, I like the sound I'm getting through them.

Mainly, I'm saying you need to start with a good-sounding mic (the cake), but it gets more impressive with the details (icing). You don't need a $2k mic, like I said before pros won't quibble about dollars and go straight for known quality. I don't know VO mics and biz so I can't tell you a $100 mic that for sure will do it, maybe there is. But, again, we are in the best days of mics now, so much variety, and quality at low prices. I could name mics (for vocals) $2-300 that are in the class of $2-3000, but all depends on whether one is the right mic for you. That's why I say search and get in on discussion boards that talk about this (gearspace, realgearonline, etc.), get advice. And lot of youtube reviews and discussions for podcasting, VO, etc. You'll get samples of people talking through these mics, you can make judgements. A lot of places allow returns too—if you want "cheap", find something promising on Amazon, and pay for a month or two of Prime and get free shipping and returns. There are some cheap Chinese mics that probably work pretty well, and the reviews will give you an idea of whether they hold up on quality.
 
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