How do various mics actually sound? at DVinfo.net

Allan Black · April 6th, 2025, 10:52 PM

This guy wanted to know too, so he went about finding out. To follow and understand him, pause his video to study his graphs.

But he’s very clever and this is interesting …

Cheers.

Paul R Johnson · April 7th, 2025, 01:32 AM

I watched that video and had to smile. He thinks he covered all bases, collected so many mics, yet forgot totally about the basic physics. His choice to use music doubly messed things up. If you also add in the fact that one part of his process involved his own hearing, and others perhaps, adds yet another variable.
I remember vividly a senior guy at the BBC, years back talking about the engineering of microphones. None of his comments are addressed by the video here.

The basic premise of recording is that what is generated by the sound source gets recorded. There is then a very similar process to return this to the ear,

First thing is to analyse the sound we are presented with. The example used on me, years back was a musician playing a single 440Hz tone. One note and we instantly say "piano", "female voice", "clarinet", "trumpet" etc. It is one note, one waveform, yet we know what it is by the overtone series - all those odd and even harmonics. Following this through - EQ and maybe even the entire microphone's capability will have the potential to change a sax into a piano (being a bit extreme).

The other thing with microphones is the physics relating to diaphragms. The idea that they faithfully move in the pressure wave and reproduce in voltage/capacitance changes, the pressure wave. Clearly they don't. Very few people consider those weird measurement mics - the omni ones with a very thin snout. If you research these, you find out some cool stuff. I'll try to dilute it down a bit, but the premise will hold.

Imagine one of the big diaphragm mics - sound from a snare drum as an example, it travels in a straight line and hits the centre of the diaphragm, and moves it a miniscule amount. If the snare is at right angles to the diaphragm, the sound waves that hit the edges of the diaphragm have a tiny bit further to travel, so will be fractionally later. Clearly this happens, but we don't hear it - or do we? A small electret would have less distance to the edges so less delayed arrival, and that measurement mic has a small opening, so has the least. Hence why measurement mics have a very small capture area.

We are all familiar with frequency response plots, but they simply measure how much signal at individual frequencies. Imagine a windspeed plot - it totally lacks one other component - gusts. How destructive winds can be depends on the speed, but vitally, gusts. Going back to mic plots, we rarely see the useful ones anymore - people are obsessed with them displayed as 20-20K. People like AKG, Sennheiser and Neumann always put them superimposed onto polar diagrams, so you could see the pattern changing as frequency increased.

He also forgot to consider how different diaphragms respond to transients. Dynamic mics have all that copper wire, and the extra mass the more substantial diaphragm has, compared to the larger gold sputtered mylar types. Put bluntly, it's physics again - a dynamic has more inertia components - the movement of a stiffer and heavier diaphragm is not the same as a thin, light one. In history, we have mic components that have adjustable tension. In the U series Neumanns and similar designs, the tension of the diaphragm is done with screws. In ribbons, the number and sharpness of the corrugations and the tension put on when screwing them up. The real engineers in lab coats, tightening them up, just enough.

The video is flawed, because he failed to take the physics into account - making huge assumptions. Using music instead of spot frequency tones introduces variations in the test that some mics will respond well to, but other respond badly.

It is a great video, but his test method is crazily flawed, making it opinion, not fact. The frequency response traces are meaningless - just a snapshot in time. The idea to take the electronics away does not just remove EQ, it removes the critical design components for the capsule. Those parts are important. We stick cars on dynomometers, so it's not just the engine, but the transmission and even tyres that get measured. When we test the engine in isolation, it tells you very little about how the car will perform.

Putting a Stradivarius or a Student violin on a frequency response chart would probably be impossible to evaluate. One is better. Would you be able to tell from the response curve?

Greg Miller · April 12th, 2025, 03:37 PM

I started watching and thought, "this guy's a showman." But is he an engineer?

So many flaws. The speaker is on a big flat piece of plywood. Does it resonate? Harry Olsen would say that it shouldn't be flat, he designed speakers with curved enclosures for a reason.

The mic might be in the same place every time, but is it the right place? Is it the right distance? What about proximity effect? If he pulls it back to avoid proximity effect, then he has a lot of interference from room acoustics. Etc. etc.

As I was thinking about all this he got to "What is flat." I won't print the spoiler here, in case others want to watch the video past this point. But that's when I stopped watching.

You just can't replace an anechoic chamber and calibrated equipment with a smiley face on ewetoob.

Too bad. It might be interesting to see someone do it right.

Thanks for posting it, though. It keeps us thinking, and takes our mind off politics for a few minutes.

April 6th, 2025, 10:52 PM	#1
Allan Black Inner Circle Join Date: Sep 2006 Location: Sydney. Posts: 2,985	How do various mics actually sound? This guy wanted to know too, so he went about finding out. To follow and understand him, pause his video to study his graphs. But he’s very clever and this is interesting … YouTube (Short URL) Cheers. __________________ Drink more tap water. On admission at Sydney hospitals more than 5% of day patients are de-hydrated. Last edited by Allan Black; April 6th, 2025 at 11:22 PM.

April 7th, 2025, 01:32 AM	#2
Paul R Johnson Inner Circle Join Date: Nov 2005 Location: Lowestoft - UK Posts: 4,056	Re: How do various mics actually sound? I watched that video and had to smile. He thinks he covered all bases, collected so many mics, yet forgot totally about the basic physics. His choice to use music doubly messed things up. If you also add in the fact that one part of his process involved his own hearing, and others perhaps, adds yet another variable. I remember vividly a senior guy at the BBC, years back talking about the engineering of microphones. None of his comments are addressed by the video here. The basic premise of recording is that what is generated by the sound source gets recorded. There is then a very similar process to return this to the ear, First thing is to analyse the sound we are presented with. The example used on me, years back was a musician playing a single 440Hz tone. One note and we instantly say "piano", "female voice", "clarinet", "trumpet" etc. It is one note, one waveform, yet we know what it is by the overtone series - all those odd and even harmonics. Following this through - EQ and maybe even the entire microphone's capability will have the potential to change a sax into a piano (being a bit extreme). The other thing with microphones is the physics relating to diaphragms. The idea that they faithfully move in the pressure wave and reproduce in voltage/capacitance changes, the pressure wave. Clearly they don't. Very few people consider those weird measurement mics - the omni ones with a very thin snout. If you research these, you find out some cool stuff. I'll try to dilute it down a bit, but the premise will hold. Imagine one of the big diaphragm mics - sound from a snare drum as an example, it travels in a straight line and hits the centre of the diaphragm, and moves it a miniscule amount. If the snare is at right angles to the diaphragm, the sound waves that hit the edges of the diaphragm have a tiny bit further to travel, so will be fractionally later. Clearly this happens, but we don't hear it - or do we? A small electret would have less distance to the edges so less delayed arrival, and that measurement mic has a small opening, so has the least. Hence why measurement mics have a very small capture area. We are all familiar with frequency response plots, but they simply measure how much signal at individual frequencies. Imagine a windspeed plot - it totally lacks one other component - gusts. How destructive winds can be depends on the speed, but vitally, gusts. Going back to mic plots, we rarely see the useful ones anymore - people are obsessed with them displayed as 20-20K. People like AKG, Sennheiser and Neumann always put them superimposed onto polar diagrams, so you could see the pattern changing as frequency increased. He also forgot to consider how different diaphragms respond to transients. Dynamic mics have all that copper wire, and the extra mass the more substantial diaphragm has, compared to the larger gold sputtered mylar types. Put bluntly, it's physics again - a dynamic has more inertia components - the movement of a stiffer and heavier diaphragm is not the same as a thin, light one. In history, we have mic components that have adjustable tension. In the U series Neumanns and similar designs, the tension of the diaphragm is done with screws. In ribbons, the number and sharpness of the corrugations and the tension put on when screwing them up. The real engineers in lab coats, tightening them up, just enough. The video is flawed, because he failed to take the physics into account - making huge assumptions. Using music instead of spot frequency tones introduces variations in the test that some mics will respond well to, but other respond badly. It is a great video, but his test method is crazily flawed, making it opinion, not fact. The frequency response traces are meaningless - just a snapshot in time. The idea to take the electronics away does not just remove EQ, it removes the critical design components for the capsule. Those parts are important. We stick cars on dynomometers, so it's not just the engine, but the transmission and even tyres that get measured. When we test the engine in isolation, it tells you very little about how the car will perform. Putting a Stradivarius or a Student violin on a frequency response chart would probably be impossible to evaluate. One is better. Would you be able to tell from the response curve?

April 12th, 2025, 03:37 PM	#3
Greg Miller Trustee Join Date: Jan 2011 Location: Pennsylvania Posts: 1,796	Re: How do various mics actually sound? I started watching and thought, "this guy's a showman." But is he an engineer? So many flaws. The speaker is on a big flat piece of plywood. Does it resonate? Harry Olsen would say that it shouldn't be flat, he designed speakers with curved enclosures for a reason. The mic might be in the same place every time, but is it the right place? Is it the right distance? What about proximity effect? If he pulls it back to avoid proximity effect, then he has a lot of interference from room acoustics. Etc. etc. As I was thinking about all this he got to "What is flat." I won't print the spoiler here, in case others want to watch the video past this point. But that's when I stopped watching. You just can't replace an anechoic chamber and calibrated equipment with a smiley face on ewetoob. Too bad. It might be interesting to see someone do it right. Thanks for posting it, though. It keeps us thinking, and takes our mind off politics for a few minutes.