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What can you tell me about condenser microphones?

thefsb

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I am in need of an education and the 50,000 mansplainers in the youtubes aren't helping much.

To try to understand specs a bit better, I chose 3 budget condensers from one brand: sE Electronics.

The differences that seem interesting but that I don't really understand are diaphragm size and self noise.

What tradeoffs are there with diaphragm size? Sensitivity v. distortion?

And what about self noise? 7 dB difference seems like it might be important to me. My mics ((neither very good: a budget AKG dynamic handheld and a Sure SM35 small-capsule electret) both require a lot of preamp gain and I can hear them even with my tinnitus.

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I can understand when to use a pad but I'm a bit unsure what the high-pass filter is for. I can apply whatever filters I want to the recorded digital file. Is the idea that attenuating unwanted low frequencies can allows higher preamp gain and therefore higher SNR for the desired frequencies?
 

Blumlein 88

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Larger diaphragms will generally be more sensitive, have lower self noise, and become directional at higher frequencies.

Cardioids have proximity effect. That means when you get close to them (2ft or less) the bass response starts to go up. The common example being the heavily low-end dominant sound of an announcer with his mouth right on top of the microphone. A high pass filter rolls off somewhere around or just below 200 hz so a singer can get say 6 inches from the microphone and still have a reasonable low end balance. And yes in some circumstances it helps with cutting out low frequency noise you don't want to record anyway.

Self Noise- if you recorded silence in an anechoic chamber you'd still get some low level noise. That is the self noise of the microphone. The rating tries to equate the level of self noise with what level of real noise would sound of the same loudness. Generally 16 db or less isn't a problem unless you are doing something specialized like say recording a grasshopper munching on some grass in a quiet setting. Most of the time ambient noise more than swamps this out.

SNR throws some people off on microphones. It is a standard to reference 94 dbSPL as that represents 1 pascal of pressure. So the standard microphone SNR is 94 db minus self noise. So with a sound level of 94 db SPL you'd have 78 db between that and the self noise of a microphone with 16 db of self noise. With 9 db of self noise your SNR is 85 db. This too usually is swamped by other ambient noises.

Now condensors and electrets usually are very sensitive requiring less gain. Ribbons and dynamics require lots of gain often nearly all you have.

If you are planning on buying more microphones, what use do you have in mind for it?
 

DVDdoug

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A smaller diaphragm usually means stronger highs and possibly less sensitivity.* "Large Diaphragm Condensers" (LDCs) cardioid (directional) mics are the most popular type of mic used for vocals (and almost everything else) in pro studios.

The main difference in sound quality or "character" with different mics is frequency response (and flat mics are generally not considered desirable). Some people go overboard trying to find the "perfect mic" for every situation and if you own a pro studio you can to that. Otherwise you can just use EQ, ord there is software so one mic can "model" another.

Self noise is from the internal phantom powered "head amp" and it's equivalent to what the noise would be if it were acoustic room noise (dB SPL). Even a pro studio is unlikely to be down at -16dB SPL, so the room noise or preamp noise will dominate.

A more sensitive (higher-output) mic helps to overcome preamp noise. If you have to crank-up the preamp you're also cranking-up the preamp noise.

The high-pass filter is for filtering-out low frequency noise when you're not recording bass guitar or a kick drum, or maybe piano, etc. Voice (and most instruments) doesn't contain any low frequency information so any low frequencies are just noise/junk so it's usually filtered-out. Low frequency often dominates acoustic room nose, although it might not be heard and might not show-up in an an A-weighted measurement.

Dynamic mics are less sensitive, and the highs are often rolled-off. But they don't have any internal electronics so they don't need phantom power and they are almost impossible to overload. Some interfaces don't have enough gain with dynamic mics unless you're recording a loud electric guitar or drums.


P.S.
* Lower sensitivity (of the diaphragm) can be made-up for in the head amp so this won't always be reflected in the specs, but higher gain tends to mean more noise.
 
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thefsb

thefsb

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If you are planning on buying more microphones, what use do you have in mind for it?
Voice, mostly spoken. And acoustic guitar.

A couple of interesting options are sE8 and Aston Origin. I expect either would satisfy in terms of performance so I need to think about practicalities. The local Guitar Center has an Aston Origin in stock so I could check it out there.
 

Blumlein 88

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Voice, mostly spoken. And acoustic guitar.

A couple of interesting options are sE8 and Aston Origin. I expect either would satisfy in terms of performance so I need to think about practicalities. The local Guitar Center has an Aston Origin in stock so I could check it out there.
I don't know the Ashton, but that se8 gives lots of value.
 
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thefsb

thefsb

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I don't know the Ashton, but that se8 gives lots of value.
You have experience using sE8?

A comment on Gearspace: "The cardioid capsule has very very extended lows, and stand rumble and handling noise is a problem unless you use the filters. Even with the lowcut filters engaged, I would recommend a GOOD suspension mount like the Rycote INV-7." That sounds fine for guitar but for long sessions doing voice the Ashton may be more forgiving.

Speaking of long speaking sessions, dunno if it's ok to mention a new podcast I'm involved in here. The first episode released last week is perhaps of interest here. It's all about side B of the Mile Davis album In a Silent Way.
 

dasdoing

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a condenser is not always the best option. if the acoustics where something is recorded are bad, a dynamic mic will capture less of the bad reflections. same is true for any background noise
 

Blumlein 88

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You have experience using sE8?

A comment on Gearspace: "The cardioid capsule has very very extended lows, and stand rumble and handling noise is a problem unless you use the filters. Even with the lowcut filters engaged, I would recommend a GOOD suspension mount like the Rycote INV-7." That sounds fine for guitar but for long sessions doing voice the Ashton may be more forgiving.

Speaking of long speaking sessions, dunno if it's ok to mention a new podcast I'm involved in here. The first episode released last week is perhaps of interest here. It's all about side B of the Mile Davis album In a Silent Way.
Yes very briefly. It was mounted in a shock mount. One of those universal types. Wasn't really a problem that I recall. Whether the Ashton is better I don't know.

As for the podcast, you can ask one of the mods or Amir. @amirm or @AdamG247 should be able to let you know about linking a podcast you have going.
 

dfuller

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What tradeoffs are there with diaphragm size? Sensitivity v. distortion?
Smaller diaphragms are usually flatter but less sensitive (i.e. higher s/n ratio). Larger are less flat but that isn't always a bad thing (first rule of recording is "everything is an EQ" - from the mic on in).
I can understand when to use a pad but I'm a bit unsure what the high-pass filter is for.
It knocks down plosives some and cuts proximity effect some.
Cardioids have proximity effect.
Any non-omni mic has proximity effect.
Voice, mostly spoken. And acoustic guitar.
I'd look into a Warm WA47 Jr. Very nice sounding mic. The top end isn't hyper-exaggerated like a lot of cheap condensers are (this is something I want ASR to test, honestly - but I don't really know how you would test them sans anechoic).
 
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thefsb

thefsb

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(this is something I want ASR to test, honestly - but I don't really know how you would test them sans anechoic).
Can the anechoic be small for those tests?
 

TimW

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I have a pair of SE8's I use for recording stereo, usually in a ORTF configuration since I have a 3D printed mount for it. They sound great on acoustic guitar to my ears. I don't use the low cut because I can EQ in my DAW with more control.

But if I was going to get just one good mic for acoustic guitar and voice it would be a LDC. I'm a big fan of my Micparts.com modded MXL 990 for this. Mine is tuned for a slight bump in upper mids but not like cheap condensers which often have a large peak in the low treble. It has low noise and high sensitivity and pics up on small details very well. I hear their pre-built Roswell Pro Audio microphones perform similarly.

Keep in mind that condensers will pickup more room noise so they aren't usually the first choice when it comes to podcasting where dynamics like the SM7B and EV RE20 are most common. I'm cheap so I use an SM57 with the presidential A81WS windscreen for podcasting.
 

Pluto

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if the acoustics where something is recorded are bad, a dynamic mic will capture less of the bad reflections.
Eh?

There is no fundamental connection between the technology employed by a particular mic and what it will, or will not, hear. Just like most other things in audio, two mics of identical specification (and directivity) will sound the same regardless of their underlying technology.

If your recording has too much unpleasant acoustic you have two options
  • get the mic(s) closer
  • use a more directional mic (but this approach, itself, has other issues of which you need to be aware)
 

dasdoing

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Eh?

There is no fundamental connection between the technology employed by a particular mic and what it will, or will not, hear. Just like most other things in audio, two mics of identical specification (and directivity) will sound the same regardless of their underlying technology.

If your recording has too much unpleasant acoustic you have two options
  • get the mic(s) closer
  • use a more directional mic (but this approach, itself, has other issues of which you need to be aware)

it's due to the fact that condensers pick up "everything".
that's why you can't use them at live shows, for example (causes feedback; EVEN if directional)
 

Pluto

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the fact that condensers pick up "everything".
There is no such “fact”.

A microphone responds to the laws of physics at the root of its design. The reason you may have had trouble with condenser mics at live shows is that you are not choosing the right mic for the job.
 

dasdoing

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Sorry, I didn't learn my audio engineering skills from some random geezer on the 'net.

he is not as random as you might think

David won 'best album of the year' in 2018 with multiplatinum McSolaar's "Geopoetique."

also you didn't even have the time to listen, judging by how fast you replied.

you are also way to agressive to maintain a healthy dialog
 

Pluto

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Please present some pertinent facts above the standard of a sales brochure and I'd be delighted to maintain a healthy dialog.

And, quite frankly, winning "best album" with the standards of recording as they are now, attests to nothing more than his ability to produce a product that sells, not one that exhibits thorough understanding of microphone technique.

I did take a look at the video actually – the parts that mattered anyway – and it's clear that your "best album" winner doesn't have too much grasp of the effect of compression on the perceived acoustic as received by the listener.
 

Robin L

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Shure SM 58s get used as a vocal microphone on lots of commercial recordings. There's all sorts of variables for recording and one finds in time that there are no hard and fast rules. In my experience, small diaphragm condensers are good for working at a distance with certain exceptions: they are the usual choice for close miking a guitar. Not so good a choice for close miking a vocal. Tend to more susceptible to plosives than other types of microphone. Large diaphragm condensers are better for close up recordings of vocals. Microphones like the Shure SM 58 work well for close up vocals, have less likelihood of generating feedback in P.A./Live performance. I've used condenser microphones exclusively for recordings, and most of the time they were small diaphragm designs like the Neumann 140 and 130. I really liked the Octava MK 12, wide cardioid with a hot spot that boosts the treble on axis. Just point the capsules a little above the target, get a smooth, somewhat bright sound. My favorite small condenser is the Klaus Heyne modified Neumann KM 84, about as transparent a microphone as I have used.
 

Blumlein 88

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snip My favorite small condenser is the Klaus Heyne modified Neumann KM 84, about as transparent a microphone as I have used.

I recently acquired some Warm Audio WA84's. Clones of the KM84. I've not had hands on an actual KM84, but these WA84s are very good, very good for the price especially. It has a very flat response, and apparently goes a little deeper into the bass on the low end vs the real KM84.
 
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