> elec > audio > eevblog-series-of-videos-tutorials-on-microphones-with-doug-ford > eevblog-602-introduction-to-microphones-eevblog

EEVblog #602 - Introduction to Microphones

EEVblog - 2014-04-12

In the first of a series of videos tutorials on microphones, Doug Ford, former head designer at Rode Microphones explains the basics of how microphones work, the different types - carbon, dynamic, ribbon, condensor/electret, and how the omnidirectional pattern works.
Also, the internal construction of a high end measurement microphone.
http://www.dfad.com.au
Discuss on the Forum: http://www.eevblog.com/forum/blog/eevblog-602-introduction-to-microphones/

EEVblog Main Web Site:
http://www.eevblog.com
EEVblog Amazon Store:
http://astore.amazon.com/eevblogstore-20
Donations:
http://www.eevblog.com/donations/
Projects:
http://www.eevblog.com/projects/
Electronics Info Wiki:
http://www.eevblog.com/wiki/

TR2 - 2014-04-12

I love Doug. He's always so informative and easy to understand.

TheChipmunk2008 - 2014-05-06

I love any video with Doug in it, he just makes complex explanations so easy to understand, along with a sense of humour :)

TubiCal - 2014-04-12

Cool stuff, when i was a technican in a audio recording studio a came across lots of miks. The ones that impressed me the most where the sennheiser MKH types. As they used RF modulation, like the theremin, to "recreate" the audio.
The "inventor" of the condenser mike was the "Neumann" company as they´ve done the first good working condenser mike ("The Bottle"), while the ribbon technique was first introduced by UK and US based companies (Royer, BBC and RCA)

Ronald Lijs - 2014-04-12

Great video Dave, keep them coming! Hope you have now learned a bit more about sound, acoustics and audio... and how it hooks together with electronics... pretty much same with preamplifies, amplifiers, speakers, etc... all have their distinctive sound depending on how they are mechanically and electrically constructed, topology, quality and material of parts, etc...

Tony DiCola - 2014-04-12

Very informative video--looking forward to the next ones.

UOttawaScotty - 2019-05-14

These are incredible videos Dave, thanks for posting this ! Now I wanna tear apart all of my microphones

Jammit Timmaj - 2014-04-12

A lot of USA military radios and communication equipment still use carbon microphones. Very robust.

Twelve Pinch - 2014-04-12

Very Good Video. I've been watching your videos for quite a while now Dave ! And im an Actual Musician. I found this Video very useful as its seen from a Designers perspective (on top of that from a very well respected company in the music industry) and its thoroughly explained :) Keep up the good work ! greetings Chris

mcjackal - 2020-02-22

Hi Dave! Love your channel mate! I learn so much from them and I enjoy the way you explain things. I can’t seem to find all the videos from the microphone series though :-/ is there a complete playlist somewhere online? Thanks in advance!

KB0BJ Bob Jones - 2014-04-12

Thanks Dave for this very interesting lesson  I look forward to more with Mr. Ford.  As always your efforts are both educational AND entertaining.!

jix177 - 2014-04-12

Always a pleasure to see Doug on the channel.

compactc9 - 2014-04-12

I absolutely love these types of videos that teach me how things work and about the design. 

tjousk - 2014-04-12

Excellent.
Definitely looking forward to the rest of these.

Jesse Juup - 2014-04-12

Thank you for this! looking forward to the rest of the series!

jtn191 - 2014-04-12

awesome! Love the channel, any more content on audio/audio electronics/processors is more than welcome!

douro20 - 2014-04-20

Didn't know Rode was an Australian company. 
The last time I saw Rode microphones was when I was in a vocational skills competition, and they had a video news production competition in which the boom microphones used were twice as expensive as the cameras themselve

Jan Hlavatý - 2014-04-12

I like this discussion like format... more guests like this! :)

Origineller Nickname - 2014-04-12

As a hobbyist audio engineer, i find this very interesting! thank you!

Tim F - 2014-04-12

brilliant. I look forward to more audio-related vids!

SYSMATT - 2014-04-15

Premium, industrial grade, AAA rated content right there.   Wow.  Loved it

OSHbots - 2014-04-12

I'm not really "into" microphone tech, but this video was surprisingly interesting. Nice one!

Maxwell Strange - 2018-09-05

Had no idea Rode was an Australian company! Love this featured video

Daepilin - 2014-04-13

really interesting video, thanks a lot, especially to doug for sharing his knowledge :)

cypeapplejuice - 2014-04-12

Nice - wasn't expecting this, this morning & just in time for coffee - nice job guys, You're a ledgebag for setting this up Dave, good to see some more audio stuff!

Harry Conover - 2021-06-04

This guy is marvelous I love good analog design but my favorite was his referring to a tube as a Fet with a pilot light ! Beauty his last design would make a great phono preamp plenty of gain for required RIAA equalization and still very quite

timlikeen - 2015-12-10

Thanks guys.That was amazing and helpful. I'm a 59 yr old Bass player and I've bought some equipment to record some original music as well as some of my old band mates music because I want to leave some documents behind when I buy the farm and take a dirt nap lmao.Seriously,I'm in bad health and wake up in the hospital once or twice a year
with tubes coming outta every orifice in my body,not cancer or anything,but I'm trying to learn how mics work and you guys tell it like it is and I'm gonna watch every
f#$%ing video in this series.Ty

Harry Haefner - 2014-04-13

Thanks for showing.  A microphone is definitely a physics project, let alone the electronic amplification efforts!

István Fülöp - 2014-04-17

Microphones can be pretty surprising actually, for example you can use a piezo as a microphone for guitars, as an extremely precise touch sensor or as a damn loud tweeter. A very smart use of speakers is when intercoms use the speaker as both a microphone and a speaker. (Electra intercoms in Romania are made like that, in a very old model you can actually short circuit the ground with the speaker to hear the speaker at the entrance without anyone calling)

RodsofGod - 2014-04-12

Thank you Doug for all the info.. you are the man!

Filip Granö - 2014-04-12

Brilliant episode, very informative!

Wyatt Goettsch - 2020-03-14

One of the legendary episodes of EEVblog.

Daniel Walker - 2014-04-15

Really enjoyed that Dave! keep 'em coming!

HeliumXenonKrypton - 2017-11-12

One of the best audio channels I've found on YouTube. Actually, yeah . ..the best.

Mariusz - 2014-04-12

Can't wait for more microphones videos!

Dren Imeraj - 2014-04-12

Please invite a guest like this for fundamentals Friday at least once in two months, IT WAS AWESOME.

mixolydian2010 - 2014-04-13

Thanks to Doug for sharing his knowledge, great to see him again. I would like to see more videos on sound reproduction please. Having been interested in audio for years both as listener and as part of my degree, i find the term audiophool kind of distasteful and un-informing to be honest. What is really needed is a, what is good engineering and what is mutton dressed as lamb or bad engineering, discussion. Clarifying what products sex up , confuse the issue, or plain lie and those that really do the job they purport to do. Thanks again Dave for the videos.

Steve Nordquist - 2014-12-01

It sensibly acknowledges Beats and other unparticular musical components that make up a highly variable and substantial hunk of markets, which are otherwise unexplained (or tells to interdiction, bellwethers, RFQ gaming, illicit trades...) Your suggestion of categorical brand/ad-agency/inventor/OEM/trope/patent-by-patent/licensing-agency-by-licensing-agency sorting is surely more distasteful (though not a big problem for Hadoop users,) if I take it like that! Perhaps you're suited well by the RED (camera/cue/sound capture and edit in camera) licensed capability-rolling sites, or other sound engineer kin? No wait, he said that once, and bad-mouthed one kind of mic. (potential across a diaphragm in a magnetic field; vocal pop shields in place; the bag camera of directional sensitivity) which is a particular $(1-80)k sort of foolishness more about gig safety and session fidgetproofing than engineering. (As for lamb fancy; what?)

If you want to pipe in with an explanation of how highly selective shotgun mics work with low profile, that's kind of thrilling audio telescope work that freed artists from wearing multiple mic/radio boxes.

Steve Nordquist - 2014-12-01

@Steve Nordquist psst. EEVBlog #611 continues the Condenser Mic discussion. Y'think he rolls into patents and other IP?

Jindřich Makovička - 2014-04-13

The High energy multimeter destruction video kicked ass... Nice to have Doug back on the stage :-)

jeromekerngarcia - 2014-04-15

Doug's a cool guy. I'd sure like to hear him explain how a single tube shotgun mic works!

Mch Gartenwohnung - 2014-04-12

Keep up the good work! Thanks!

Dustin - 2021-06-13

27:34 should have been the cover picture. I had never converted speed of sound to ft/s always have used m/s even though I am a Yank, but it is interesting to know that sound travels the distance of almost 4 football fields per second.

Gustav Licht - 2020-09-17

Does the uniformity of the response matter with sufficiently good DSP? Also, the size of the diaphragm and wavelength relatino sounds a lot like near field/far field in RF or photonics.

Martin D A - 2014-04-12

If it works as a mic it will generally work as a speaker....Take a look at the Apogee loudspeakers, they are a sight to behold. I was running a service dept. in a high end hi fi shop in the 90s when these arrived and a pair were in for service. A curious colleague was looking at one and had an allen key in his hand...As I watched I was too slow to react as he moved the allen key toward the ribbon...The massive magnetic field caught hold and whipped the key from his hand..and PLONK..stuck itself to the ribbon!
Microphone technology and outstanding quality recording technique and microgroove arrived together in the early 50s allowing us to hear close miked crooners on all their glory for the first time...Listen to Buddy Holly...Never been surpassed for quality, and it is obvious.

666alikat - 2014-04-12

Cant wait for part 2!

redtails - 2014-04-23

Some people often ask why microphones don't simply mimic human hearing by measuring frequencies separately. In the human ear, there's a couple thousand neuron receptor cells that each respond to a different frequency. If it works for us, why dick around with measuring wobbly membranes?

It's interesting to consider that mammalian ears (including human ears) measure frequency and not time. This might seem like a pretty silly thing to do, because it takes a lot of effort to construct (biological) band-pass filters that are going to be accurate enough for musical hearing (cochlear implant designers had to learn this the hard way). Though thinking about the limitations of biology, it makes sense why hearing is based on frequency and not time. If you measure frequency separately, you can equalize by simple changing the gain of each frequency channel (biological gain), instead of having to do weird FFT or AC coupling mechanisms, which might as well be impossible in biology. This biological equalization happens all day long. If you endure a specific tone for some time, you'll be desensitized to it. 

If you want to construct an electric variant of the ear.. you'd need some way to construct tens of thousands of little band-pass filters that are accurate to single hertz. Anyone knows if this is currently possible at all? 

So, in a way, biological hearing is better as frequency-based, while electronic sound capture is best as time-based (currently)

Stephen Tack - 2014-04-14

Carbon granule microphones are still produced and used in the last bastion of archaic audio technology: Harmonica Amplification

The abysmal frequency response and overall "lo-fi" sound is sometimes desirable when close mic'ing a source that could otherwise sound overly bright and harsh, like a harmonica. Same thing goes for diaphragm coupled "crystal" piezo microphones.

Karlo Horčička - 2021-10-08

Harmonica or accordion?

Stephen Tack - 2021-10-08

@Karlo Horčička I don't know much about accordion amplification. But an accordion is a giant harmonica with bellows, so maybe 🤷🏻

Kevin Beckenham - 2017-09-12

Excellent documentary on microphones Dave & Mate who doing all work,thank's.

Cooljosh3k - 2014-04-15

*Despite what I already know, your Fundamental Fridays teach me much more.

A suggestion for a future FF episode: various oscillator circuits and how they work.*

ProgramOrBeProgrammed - 2014-04-17

The eevblog never fails to impress.

BoredErica - 2014-04-13

Can you do a video on audio basics? Sine wave, oscillascope, Nyquist, resistance, Ohms, all that stuff. I've seen a video on this kind of stuff but the one I saw assumed I was taking a class in audio engineering already or something, it lectured in Greek to me.

CoolDudeClem - 2017-01-02

One thing I've learned is to NEVER remove that paper/cloth tape that covers the vents on a dynamic microphone element, it sounds crappy if you do that.

ELECTROHAXZ - 2018-02-15

The noise filter!