“Gaming” measurements

[Summit]

1 hour ago, March Audio said:

It's not about microphones it's about your brain.

 

If you find yourself in a hole, stop digging :)

[Summit]

15 hours ago, fas42 said:

 

Is this the same thing as a camera can't "see" in the same way as two eyes and a brain? Therefore, photos and videos will only ever be a (poor) facsimile of seeing live?

 

Yes its the same only that we are easier fooled then it comes to sound. 

[March Audio]

20 minutes ago, Summit said:

 

If you find yourself in a hole, stop digging :)

I was going to respond but this is such a meaningless  comment there is nothing to actually say. Hahahaha 

[March Audio]

2 hours ago, Jud said:

 

So is it the engineers working at the microphone companies who after decades are not competent to make a product that will come anywhere near working for its intended purpose? What measurable differences are there between what you would hear at the venue and the mic capture? If it's a live performance using mics, amps, and speakers, why doesn't running the same mic output through a different but well designed amp and speakers give me a very reasonable duplication of that performance?

 

You mentioned it won't sound as "echoey," so is it the producers who haven't over decades of recording learned to capture echoes? And if they haven't properly captured the room, surely there's DSP for that? If there isn't DSP that can do the job and the room is an insuperable barrier, then there are headphones. I know you mentioned headphones create a closed chamber, but there have been "open air" headphone designs for a half century. Haven't they got it reasonably correct by now?

 

I suppose what I'm asking is in what measurable respects and where does our current recording and reproduction chain fall down?

 

 

I think this is like you read a completely text to what I actually wrote.

 

The simple point was that microphones don't "hear" in the same way two ears and a brain do.  That's plainly obvious to anyone who had actually made recordings.

 

The recordings I posted were a simple demonstration of how this can manifest itself.  That didn't equate to its "impossible to record music to a reasonable accuracy".  I talked about some of the techniques that bring the sound closer to what we perceive when actually hearing in person plus the issues that go hand in hand with that.

[March Audio]

3 hours ago, Jud said:

 

So is it the engineers working at the microphone companies who after decades are not competent to make a product that will come anywhere near working for its intended purpose? What measurable differences are there between what you would hear at the venue and the mic capture? If it's a live performance using mics, amps, and speakers, why doesn't running the same mic output through a different but well designed amp and speakers give me a very reasonable duplication of that performance?

 

You mentioned it won't sound as "echoey," so is it the producers who haven't over decades of recording learned to capture echoes? And if they haven't properly captured the room, surely there's DSP for that? If there isn't DSP that can do the job and the room is an insuperable barrier, then there are headphones. I know you mentioned headphones create a closed chamber, but there have been "open air" headphone designs for a half century. Haven't they got it reasonably correct by now?

 

I suppose what I'm asking is in what measurable respects and where does our current recording and reproduction chain fall down?

 

 

Re headphones there is a lot to it.  When you listen to speakers you have your whole torso and head affecting the sound.   Headphones are obviously a different situation .  Open headphones are still an enclosed chamber, to your ear.  it's just the back ofvthe driver is open to the world.  Angle of the sound makes a difference. Free field and diffuse field.

 

I have had a look for a video, this one might help although I have only watched part of it.

 

 

[semente]

This measurement appears to show a tweeter's high-level resonant peak at 27kHz producing/modulating harmonic distortion at 13.5kHz and 9kHz:
 

[Jud]

1 hour ago, March Audio said:

I think this is like you read a completely text to what I actually wrote.

 

The simple point was that microphones don't "hear" in the same way two ears and a brain do.  That's plainly obvious to anyone who had actually made recordings.

 

The recordings I posted were a simple demonstration of how this can manifest itself.  That didn't equate to its "impossible to record music to a reasonable accuracy".  I talked about some of the techniques that bring the sound closer to what we perceive when actually hearing in person plus the issues that go hand in hand with that.

 

So can we get something out of the recording chain that sounds reasonably close to real life or not?

[Jud]

1 minute ago, semente said:

This measurement appears to show a tweeter's high-level resonant peak at 27kHz producing/modulating harmonic distortion at 13.5kHz and 9kHz:
 

 

Audible levels or no?

[semente]

38 minutes ago, Jud said:

 

Audible levels or no?

That is a good question; I don’t think that it was tested for that particular speaker.

But it could be an indication for why some people can’t get alone with some hard-domed tweeters that produce a strong peak close to the top of the audible range. It requires further investigation.

[manueljenkin]

5 hours ago, March Audio said:

The simple point was that microphones don't "hear" in the same way two ears and a brain do.  That's plainly obvious to anyone who had actually made recordings.

So you're telling ADCs hear the way our bain does, and especially only sine squiggles? I'm asking because most of your other "quest for objectivity" seems to hinge on that. And suddenly when it comes to microphones you become a hypocrite and additionally throw in uncorrelated jargon.

[March Audio]

7 hours ago, Jud said:

 

So can we get something out of the recording chain that sounds reasonably close to real life or not?

Reasonable yes, but rarely like actually being there.  If you individually mike instruments you then you have to mix levels and pan positions.  It's then an artificial construct at the whim of the person  mixing.

[fas42]

8 hours ago, Summit said:

 

Yes its the same only that we are easier fooled then it comes to sound. 

 

We are not fooled, at all, 😉 ... when was the last time you heard audio reproduction - and I'm not talking about some transient sound in the whole - fool you? That is, you found it difficult to perceive anything in the presentation which "gave the game away" - you could very easily convince yourself you were listening to the "real thing".

 

It's quite easy to set up a rig, and play the 'right' recordings which sound very, very impressive - but that's not the same thing as being convincing ... a person who is not the slightest bit interested in audio matters would just laugh at you if you asked him whether a system he just listened to fooled him ... "Gee, it was really impressive - but of course it was obviously a hifi setup!".

 

That is, essentially all playback always adds clues to the SQ, which means your hearing can always pick that it's fake ...

[March Audio]

6 hours ago, semente said:

This measurement appears to show a tweeter's high-level resonant peak at 27kHz producing/modulating harmonic distortion at 13.5kHz and 9kHz:
 

Thanks for posting that.  As previously mentioned I'm going try and find time today to perform some tests to investigate this.

 

It's often gets mentioned as an issue, but apart from your plot there I don't think that I have ever seen any data to support it.

 

One thing I would say is that you will never have sound levels of 90dB at 20+ kHz, so that test is quite unrealistic compared to what you will have with real music signals.  At realistic signal levels those distortion products will almost certainly been in the noise floor.

[Jud]

1 hour ago, March Audio said:

At realistic signal levels those distortion products will almost certainly been in the noise floor.

 

I like to look at this slightly differently: Does it raise the noise floor enough to make it more difficult, less comfortable, to perceive very low level musical details that would otherwise be audible?

[March Audio]

 

1 hour ago, Jud said:

 

I like to look at this slightly differently: Does it raise the noise floor enough to make it more difficult, less comfortable, to perceive very low level musical details that would otherwise be audible?

Well impossible to say on that particular data, we would have to re-run the test at realistic levels to find out.

 

However this is the test I performed a few minutes ago.  Same set up as the IM test a few days ago. 

 

Our Sointuva speaker

Earthworks M23 mic (-1dB at 35kHz)

Motu Ultralight MK5 at 96kHz SR (48kHz BW)

Purifi amp

Mic distance about 0.5m

 

Please bear in mind this is a very casual test and there is background noise in the room

 

 

The Sointuva uses a Bliesma T34A aluminium dome tweeter.  

Manufacturer data

 

 

Independant HiFi compass data

 

My data in this test config (full speaker with crossover etc.  the dip around 24Khz is due to mic distance)

 

So all the data concurs with a dome resonance centred around 29.5kHz

 

Background noise

 

85dB single sine at 29.5khz

 

IM two sine at 29 and 30kHz @ 85 dB (As the other day you can see minor IM at 1kHz and around the 2 main tones.

 

As you can see the levels are at the threshold of hearing and would never be heard. (yes the mic level was calibrated prior to test with an acoustic calibrator)

 

OK this is one speaker, the results will vary from speaker to speaker.   I also have a Usher BE718 and a Totem Acoustics model with diamond and metal dome tweeters I can test.  However with this one a total non issue even with levels higher than would be seen with real music.

 

 

[March Audio]

BE718

 

 

Resonance at 22.5kHz ( yes rather close for comfort!)

 

 

Background

 

IM test

 

Again nothing significant happening

[March Audio]

Totem something or other

 

 

 

No significant resonances seen

 

Background

 

IM test at an arbitrary 25 and 26kHz (no resonance to line up with)

 

Much higher levels of IM around the main tones, but again no unexpected spuria.  Simply a higher distortion tweeter.

[March Audio]

Just to note the signal levels above are actually very high compared to what you find in real music recordings.  The recordings with the highest levels above 20kHz I have in my collection are from 2L.  In the examples below the highest level around 24kHz is about -64dB.  So if you were playing the music at a general listening level of 90dB those signals around 24kHz would only be 25dB in level. As such its not possible to create any audible issues.

 

 

 

[semente]

2 hours ago, March Audio said:

Just to note the signal levels above are actually very high compared to what you find in real music recordings.  The recordings with the highest levels above 20kHz I have in my collection are from 2L.  In the examples below the highest level around 24kHz is about -64dB.  So if you were playing the music at a general listening level of 90dB those signals around 24kHz would only be 25dB in level. As such its not possible to create any audible issues.

 

 

 

I can’t access my music for a few days but I don’t think that 2L is a good choice. Rock and sometimes jazz drum kits are mic’Ed close and produce a lot of energy at the top. Perhaps you could look there, though I agree that full-scale at 20kHz is unlikely.

 

You could perhaps try Barry Diament/Soundkeeper, he has a few samples available for download but uses a mic pair only so not too close. Still they’re wide-band mics.

[March Audio]

10 minutes ago, semente said:

I can’t access my music for a few days but I don’t think that 2L is a good choice. Rock and sometimes jazz drum kits are mic’Ed close and produce a lot of energy at the top. Perhaps you could look there, though I agree that full-scale at 20kHz is unlikely.

 

You could perhaps try Barry Diament/Soundkeeper, he has a few samples available for download but uses a mic pair only so not too close. Still they’re wide-band mics.

Will take a look :)

 

Just found Daft punk in the -50dB area

 

[Confused]

On 6/2/2021 at 2:41 AM, fas42 said:

Thanks for those clips ... the music sections are very revealing - things sound fine with the intro, but once the full band kicks off, the SQ degrades, badly - this is pretty typical of an unsorted setup ... so long as it's not tested with more dynamic material it does well; but then doesn't cope with more demanding music.

Interesting.  I have to be honest here, but listening to the clips on headphones I do not hear the SQ to degrade badly once the full band kicks off.  I am not saying that I am hearing 100% perfect sound reproduction, which is to be expected for such a recording, but I am certainly not hearing such dramatic degradation as you describe.

 

Maybe you can hear things that I cannot.  Who knows?  Possibly a blessing in my case, as it will allow me to listen to unsorted rigs in utter bliss, simply enjoying the music.

[fas42]

14 hours ago, Confused said:

Interesting.  I have to be honest here, but listening to the clips on headphones I do not hear the SQ to degrade badly once the full band kicks off.  I am not saying that I am hearing 100% perfect sound reproduction, which is to be expected for such a recording, but I am certainly not hearing such dramatic degradation as you describe.

 

Maybe you can hear things that I cannot.  Who knows?  Possibly a blessing in my case, as it will allow me to listen to unsorted rigs in utter bliss, simply enjoying the music.

 

It sounds like what what most audio systems come across like - when recorded, it sounds like, exactly as Alan says, a "speaker in a room" - this means that the experience is not convincing, when listening in person. If the presentation was correct then the recording of the playback would sound like you were listening to the band performing in the studio. What's missing here are all the cues that accompany "big" sound - and it's obvious you're listening to speakers.

[March Audio]

30 minutes ago, fas42 said:

 

It sounds like what what most audio systems come across like - when recorded, it sounds like, exactly as Alan says, a "speaker in a room" - this means that the experience is not convincing, when listening in person. If the presentation was correct then the recording of the playback would sound like you were listening to the band performing in the studio. What's missing here are all the cues that accompany "big" sound - and it's obvious you're listening to speakers.

No Frank.  As explained its because microphones don't "hear" like 2 ears and a brain.  The speakers presentation sound superb when you are in front of them.

 

What's missing are all the cues that your brain uses to process sound when you are there in person because microphones don't capture them.

 

Put any speaker driven by any system you like in that situation and the recording will sound like a "speaker recorded in a room".

[fas42]

10 minutes ago, March Audio said:

Put any speaker driven by any system you like in that situation and the recording will sound like a "speaker recorded in a room".

 

Does this sound like a speaker recorded in a room?

 

 

 

[March Audio]

16 minutes ago, fas42 said:

 

Does this sound like a speaker recorded in a room?

 

 

 

 

Yes, absolutely!  Cant you recognise those characteristics?  Hear the room ambience separate from that of the recording?  The skewed timbre?  Try playing an original recording of the track over your hifi and those differences will become plainly obvious if you dont spot them in isolation.