"Where does the tone come from in a microphone?"

[soapfoot]

In 2023, repeatedly disclaiming with “I’m not a scientist” invites the question: “why didn’t you ask a scientist for help, then, when devising your methodology?”

Information is so easy to access now, and so many passionate experts give their knowledge so freely. It’s a shame not to draw from that largesse, especially when publicly presenting conclusions for a substantial audience (who will then accept those conclusions as truth)

 

[Marik]

As you surmise, the introduction of delay between the front and rear paths makes pressure-gradient mics non MP. Correlation between frequency response and transient is not verified above about 5kHz.

Abbey,

What is the measure and practical meaning of non MP? Ribbon microphone is also pressure gradient, with pressure difference being predictable driving force on the diaphragm up to half of the front-to-back wavelength distance (which can be pretty high). Ribbons have an excellent off axis (most of condensers could ever dream of) and phase behavior. Are the ribbons supposed to be MP, or non MP?

But isn't it the case of many recorded tracks? Close micing is dominant in many styles of music. Classical music excluded...or not.

The close micing is very different to "close micing" ))). Here I see about an inch from a tweeter. There are only very few situations with such a short distance (say, some singers like to almost swallow the mic, or guitar amp). More common is some 4"-6" distance, which is completely different in terms of proximity and off axis, especially with more complex sound sources.

Best, M

 

[abbey road d enfer]

In 2023, repeatedly disclaiming with “I’m not a scientist” invites the question: “why didn’t you ask a scientist for help, then, when devising your methodology?”

Probably because a scientist may have preconceived ideas that would conflict with his methodology, however quirky it is.

especially when publicly presenting conclusions for a substantial audience (who will then accept those conclusions as truth)

By presenting all his experimentations, he lets viewers draw an opinion, to some degree.
The problem is that many viewers do not have the knowledge that would allow them to sort the wheat from the chaff.
I believe I have this knowledge, and still I found his videos interesting.

 

[soapfoot]

The problem is that many viewers do not have the knowledge that would allow them to sort the wheat from the chaff.

Well-articulated; my point was made in a sloppy fashion.

It remains true, though, that a layperson can be easily (and badly) misled by an empirical-seeming test with a deeply-flawed methodology (even one devised in good faith)

 

[abbey road d enfer]

What is the measure and practical meaning of non MP?

This was specifically in regard to the Hilbert transform, which allows establishing a bijective relationship between frequency response and phase response. This is true only for MP systems.

Are the ribbons supposed to be MP, or non MP?

This is debatable, as you can see from the exchange between ricardo and me.

The close micing is very different to "close micing" ). Here I see about an inch from a tweeter. There are only very few situations with such a short distance (say, some singers like to almost swallow the mic). More common is some 4"-6" distance, which is completely different in terms of proximity and off axis, especially with more complex sound sources.

Sure, but it doesn't completely disqualify the experiment, which is comparative.
IMO, it's less stupid than evaluating a microphone by talking/singing into it and listening with headphones...

 

[GeorgeToledo]

In 2023, repeatedly disclaiming with “I’m not a scientist” invites the question: “why didn’t you ask a scientist for help, then, when devising your methodology?”

Information is so easy to access now, and so many passionate experts give their knowledge so freely. It’s a shame not to draw from that largesse, especially when publicly presenting conclusions for a substantial audience (who will then accept those conclusions as truth)

well said!!!

 

[Marik]

IMO, it's less stupid than evaluating a microphone by talking/singing into it and listening with headphones...

I am embarrassed to confess--this is precisely how I evaluate and voice our microphones (some say with OK results) way before we even start measuring them))). Obviously, after that the mics go through rigorous studio testing with different sound sources, different distances micing, etc., but with years, with mixer, headphones, and sound source (my voice) I know well enough) I just learnt it as a point of reference and know how it will translate into other things. Usually, when I bring our mics into a studio for testing I can immediately tell them from the others.

Best, M

 

[abbey road d enfer]

I am embarrassed to admit--this is precisely how I evaluate and voice our microphones (some say with OK results) way before we even start measuring them))).

I understand that, since it's a well rehearsed exercise, you can detect faults and inadequacies.
I was referring to people going to a music shop, assessing unknown microphones with unknown headphones, hence with different bone conduction..

 

[Marik]

I understand that, since it's a well rehearsed exercise, you can detect faults and inadequacies.
I was referring to people going to a music shop, assessing unknown microphones with unknown headphones, hence with different bone conduction..

I know... just could not resist to comment on that one)))
But give me a different set of headphones and I will be completely lost for some time... until I learn well how to translate those.

I want to do some more reading, review yours with Ricardo exchange and might come with more questions about MP...

Best, M

 

[k brown]

I know... just could not resist to comment on that one)))
But give me a different set of headphones and I will be completely lost for some time... until I learn well how to translate those.

I want to do some more reading, review yours with Ricardo exchange and might come with more questions about MP...

Best, M

Just curious - what does this: ))) mean?

 

[Khron]

Just curious - what does this: ))) mean?

Probably a version of a "very" smiley face.

 

[Marik]

Probably a version of a "very" smiley face.

Or LOL...

 

[noizetoys]

I will say up front that I like Jim's videos. His 'What makes a guitar tone' series is fun. Takes serious balls to post something like that knowing that he's going to get grief (warranted or not) from the inter-webs.

Was the video:

• Scientifically accurate? Not even close.
• Enjoyable and interesting? Definitely!

His layman scientist approach is something I would like to see more people try. No, it's not going to give the most accurate results but it helps people understand the greater complexity of topics that some/most/too many 'reviewers' overlook.

We Americans do love our simple answers to complex questions.

"Use this one weird trick to turn your crap recording into a #1 Hit!"

Do I agree with his conclusions in the mic video? Not all of them, but others to align with my own experiences. Does that make them right? No, it only shows that my conclusion was experienced by someone else.

I've been fortunate to have done a number of 'shootouts' with quality singers in quality environments on quality gear with people with quality ears. Yeah, that last part is highly subjective, but whatever.

I've had instances where we had a SM7B next to a 251 on an excellent singer where we did blind test for the producer.
Did the 251 sound good? Hell yes!
I called it 'Hearing God's breath'.
Did it sound better than the SM7B? Well, 'that depends'.
On more than one occasion the producer (and pretty much everyone else) chose the SM7B because it sounded 'right'. Other times it was 'If anyone tries to touch the 251 I'll cut them!!!' because the difference was that significant.

I've heard terrible sounding 47's, C12's, 251's...you get the idea. Just like I've heard great cheap mics.

It's easy to get carried away with 'Is this X better than that Y?' and forget that ultimately the reasons people choose one thing over another are as varied as the people making the choice.

• Was it vintage nostalgia?
• Was it marketing hype?
• Did it sound better in that room/song/situation?
• Was it the only thing available?
• Etc, etc.

His use of the SM57 as the reference was interesting. I see his reasoning. Remember he's a guitarist and what is the mic most people associate with guitar? See above.
Just like when you ask someone to think of a vocal mic they think of either the SM58 or something that looks vaguely like a U87. Snare drum, kick drum, etc. all have their 'mic'.
Is it accurate or correct? No, it's just how many people think, so using it as his 'reference' makes sense (not scientifically, but you get the idea).

On this forum we sweat the details, that is after all the point. Does this capsule & circuit sound better than that one? How much difference does the head basket make? Is this transformer at this ratio sound better than that transformer at that ratio? Often we don’t see the forest or the trees, we only see the bark.
Again, that’s the point.

But keep in mind that John and Jane Doe have no idea what makes a mic sound like it does and really, they don't care.

It pretty much comes down to one question: "How does it sound?"

• If the answer is 'Good' then great, record something and get on with your life.
• If the answer if 'Not Good' then great, use a different mic until the answer is 'Good'. Then, record something and get on with your life.

Most people will never have the chance to hear God, I mean use a well maintained Telekunken E LAM 251.

I weep for those people.

Most people will never have the chance to use a vintage Neve, Urei, Pultec, etc, etc. but they've heard a plugin or clone (that includes ‘reissues') and thought it sounded ‘good’.

I do not weep for those people.

Why? Because ultimately, it doesn't matter to them. They have a tool and they use that tool. The question of "Does it sound like the ‘real thing'?" is irrelevant because they will never have the opportunity to use the ‘real thing'.

Would their product sound better if they had used the 'real thing'?

Would a painting by an unskilled artist be better if they had more Crayons in the pack?
I'll leave the answer to the reader. (For those playing along at home, the answer is 'No').

A piece of charcoal in the hands of a skilled artist will create art.

128 Crayons (I only ever got 32 which probably explains a lot) in the hands of a unskilled artist will only ever produce ‘art’ that Mom puts on the refrigerator.

The question then becomes "If that skilled artist had more Crayons would the picture be better?".
That's a 'Maybe?'.

If you don't know how to drive, getting a Lamborghini isn't going to do anything other than help you wrap yourself around a tree quicker than you would have in a Yugo.

Ok, so what's the point?

Glad you asked....

• Was the mic testing methodology valid and rigorous? No.
• Did Jim reach valid conclusions? He thought so, so Yes.
• Would a scientist reach the same conclusions? Most likely No.
• Would I recommend people trying to understand the differences in mics watch the video? Yes.

But probably not for the reasons you might think.

I would recommend it with the hope that the viewer, who is most likely someone not on this forum and has never used an over $5,000 mic, would see the video and think "Hey, I guess I don't need really expensive mics to make decent recording" and just get on with it.

Ok, enough of that.

Sorry I didn't make this post shorter, I ran out of time.


If you made it this far I owe you a cookie.


Donning Asbestos suit in 3….2….1….

 

[OneRoomStudio]

I think this was a great and fun video, but he glanced over (and then ultimately ignored) the most interesting part - testing capsule variables. He clearly showed that differences in diaphragm thickness, spacing, gold deposition, and tension made big audible differences. He even managed to identify one aspect that these variables affect is the capacitance (but completely missed things like transient response, SPL handling, and off-axis response).
Ok, great - so if nothing else, we have established that differently built/designed capsules will sound different because of those variables, which is further proved by the fact that different examples of the same mic/capsule can sound drastically different. Now we're getting somewhere...

...but then he went on to grab a poorly-built clone of a classic CK-12, which shares almost nothing with the original other than the fact that it's edge-terminated, and stated that is sounds nearly identical to the original. How did he arrive there?

Maybe if he asked his capsule builder to copy the important aspects of the CK-12 he liked (again, diaphragm thickness, spacing, gold deposition, tension, backplate hole pattern, etc, etc...) then he would have a capsule that should sound very close to the original and his point that the headamp doesn't have much of an impact on the final sound might have had some validity...but he zigged when he should have zagged.

 

[kingkorg]

I think this was a great and fun video, but he glanced over (and then ultimately ignored) the most interesting part - testing capsule variables. He clearly showed that differences in diaphragm thickness, spacing, gold deposition, and tension made big audible differences.

This is absolutely true, but the variation shown in his demo is way too inconsistent. Probably due to placement errors. You also have to do this on same exact backplate which he didn't do. Tension for example can affect certain things, and not others, however in his test it magically does. We are talking milimeters of error in placement, or microns in backplate tolerance with these OEM capsules. So that part is totally wrong. I am also shocked by the Nashville mic tech who isn't aware of anyone doing these tests. He should be the one to do them.

 

[Icantthinkofaname]

In case you hadn't noticed: AKG only exists as a brand name. They've been closed down by their current owner, Harman. No factory, no lab, no nothing in Austria remains.

And selling DIY capsules would probably lessen the hype, so I don't think it's on the menu.

FWIW, I would like it too, but I don't see it happening.

I definitely knew it wasn't the same company, but I assumed they'd still have some sort of factory.

The 414 capsules are probably an OEM derivative of an existing line.

If this turns out to be true I hope somebody manages to find out who makes them. Obviously the replacement capsules for the current model C414s are available, but I find the current mics a little tinny sounding, and I'm not sure if that's the circuit colouring the sound, or if that's from the capsule, body, etc. What I do know is I don't hear the same thing in the older ones.

 

[ricardo]

Notably the relatively insignificant differences between silly priced mics and their more sensibly priced counterparts, and also the real world differences - or rather lack of - between tube and FET mics.

but, but, BUT da cheapo mikes aren't Hand Carved from Unobtainium & Solid BS by Virgins ??

I think a bigger elephant in the room is the original intent of the iconic mike designers.

Bernhard Weingartner designed CK12, C12, C24 to have flat response especially in Fig8.

'Modern' 414s have a reputation for hyped highs so would NOT have met with his approval. He also admitted that you could probably achieve similar results with a much simpler capsule eg the Debenham et al

My own take on C414 & C12 is 'the voice of the BBC'. When we did a project for them, I was astonished to find they used a 414 voice recording as their final 'golden' test for monitor speakers in an anechoic. I can instantly recognise the rich plummy tones of C414/C12 from years of classic BBC voice.

I don't design mikes to sound like that but C414 is still one of my favourite mikes. Dunno which version

 

[ricardo]

What is the measure and practical meaning of non MP?

The strict definition is when the Phase & Log Amplitude of a Transfer Function are related by a Hilbert Transform pair.

There are several nice properties of a Minimum Phase Transfer Function but the most important practical ones are

• If you equalise a MP Amplitude response with analogue (ie usually MP) EQ, you also equalise the Phase and Impulse Response.
• A MP Impulse Response is the shortest possible for a given Amplitude Response .. which has implications for Digital EQ
• ie a MP Impulse Response or MP Amplitude / Phase, is Response as God intended

I say more about this in
Is Linear Phase Worthwhile
and
Simple Arbitrary IIRs

In da 70s & 80s, doing Hilbert Transforms was much more difficult than today. In 20+ yrs designing and measuring speakers, I've found only 2 drive units which were non-MP.
But most multi-way speakers are non-MP cos xovers.

I've measured far fewer microphones than speakers but I've yet to find a microphone which isn't MP

 

[ricardo]

IMO, it's less stupid than evaluating a microphone by talking/singing into it and listening with headphones...

I am embarrassed to confess--this is precisely how I evaluate and voice our microphones (some say with OK results) way before we even start measuring them))).

If I was a guru in my previous life, it was in the use of DBLTs to help design speakers, electronics and microphones.

If we were assessing a competitor's speaker, one cardinal rule was to always LISTEN (preferably in a DBLT) before measuring. It's all too easy to be biased by measurements.

I'm not sure how this relates to 'listening to mikes on headphones'

 

[abbey road d enfer]

If this turns out to be true I hope somebody manages to find out who makes them.

I just don't believe that Samsung has created a production unit from scratch. As I said earlier, I'm not privvy to their business, but I now that when AudioTechnica wanted to source part of their production from SEA, they selected a few existing manufacturers and started joint ventures. For example their LP140 turntable is made in the factory that made the Technics SP1200 and uses the same tooling.
When Neutrik found they needed to have a cheaper line, they selected a jobber that made a number of fraudulent copies; 1 stone, 2 birds.
I cannot prove that it's what Samsung did, but it's a hunch.