[Steve Eddy]

I agree.

At this very moment, I am humbly converting a great DSD64 recording - any way I have available - into 192/24 to be seen on the FFT. The first concern is to get recording that can not noise too much up to at least about 100 kHz - it is ANYTHING but clean and quiet out there. Which leads us to ever greater sampling rates, either in DSD or PCM.

Then again, people have dreamt of flying for ages - and it is not much beyond 100 years since Wright  brothers flew for the first time.

The Rome was not built in one day either ...

Getting a native PCM recorder would be helpful.

se

 

[analogsurviver]

Getting a native PCM recorder would be helpful.

se

EVERY on paper first DSD recorder is also PCM capable . The other way around it usually does not work. 
All it takes is is a flick of a switch or ticking a box in the Menu ...
 
Probably the biggest bang for the buck in today's audio : http://tascam.com/product/da-3000/

 

[MacacoDoSom]

 

...and these 3 kHz had to exist prior to the recording so they will be recorded and heard...

Incorrect.

If, as Analogsurviver is hypothesizing, the 3kHz results from intermodulation products produced by the ear as a result of circa 80kHz harmonics produced by the horn, then what needs to be captured and reproduced are those circa 80kHz harmonics.

se

produced by the ear? and is that good thing? I thought he wanted to hear what really happened when the horn was playing... the harmonics maybe produced by the room or whatever, but before being recorded...
if not so it make no sense...

 

[Steve Eddy]

EVERY on paper first DSD recorder is also PCM capable . The other way around it usually does not work. 
All it takes is is a flick of a switch or ticking a box in the Menu ...

Probably the biggest bang for the buck in today's audio : http://tascam.com/product/da-3000/

Oh, ok. Thought you were having a problem converting the DSD recording.

se

 

[analogsurviver]

Oh, ok. Thought you were having a problem converting the DSD recording.

se

It is just tiresome and time consuming, that's all. 
 
Now I am "armed" by a nice juicy drum solo live recording - you should see how 20-50 kHz range springs to life once the cymbals start playing 

...

 

[Steve Eddy]

produced by the ear? and is that good thing? I thought he wanted to hear what really happened when the horn was playing... the harmonics maybe produced by the room or whatever, but before being recorded...
if not so it make no sense...

He was talking about intermod products in the audible range. At first, I thought he was just confused and that he was erroneously assuming that just because something like a trumpet may have harmonic content at 80 kHz and 83 kHz that there would just magically be intermod product at 3 kHz, and that in order to reproduce that 3 kHz content, the recording would have to capture and the loudspeakers reproduce, those 80 and 83 kHz harmonics of the trumpet.

That of course isn't true. Those 80 and 83 kHz harmonics would have to be subject to some sort of non-linearity to produce a 3 kHz intermod product. So I asked him where was the non-linearity that would be responsible for that 3 kHz intermod product.

I thought I was being clever and was going to trip him up. But he replied that the ear is quite non-linear. And he's absolutely right. Not that that was something I wasn't aware of, just that I had erroneously assumed that he was making an erroneous assumption. So my bad on that account.

And that wasn't my only erroneous assumption.

I'd never really read any of his posts very thoroughly before, and just jumped on the bandwagon dismissing him as a troll.

But a recent event caused me to reconsider. It was when he was arguing cable capacitance vis a vis electrostatic headphones. After reconsidering, I concluded he was making some very good points.

So I sent him a PM and asked him if he would be up for a good old fashioned telephone conversation so I could get to know him a little better than would be possible from just posts in a forum.

He was and we had a very nice talk yesterday, which lasted for an hour or so before I had to break to take another call.

While I can't say I would agree with him on everything, I found him to be a genuinely nice guy who is actually quite knowledgeable, and I will no longer dismiss him as a troll. Instead, I will just exercise more patience with him, and look forward to our next telephone chat.

se

 

[Steve Eddy]

It is just tiresome and time consuming, that's all.

Gotcha.

Now I am "armed" by a nice juicy drum solo live recording - you should see how 20-50 kHz range springs to life once the cymbals start playing :atsmile: ...

Oooh. Can you share? Not for any analysis, I just like a good drum solo.

se

 

[RRod]

He was talking about intermod products in the audible range. At first, I thought he was just confused and that he was erroneously assuming that just because something like a trumpet may have harmonic content at 80 kHz and 83 kHz that there would just magically be intermod product at 3 kHz, and that in order to reproduce that 3 kHz content, the recording would have to capture and the loudspeakers reproduce, those 80 and 83 kHz harmonics of the trumpet.

That of course isn't true. Those 80 and 83 kHz harmonics would have to be subject to some sort of non-linearity to produce a 3 kHz intermod product. So I asked him where was the non-linearity that would be responsible for that 3 kHz intermod product.

I thought I was being clever and was going to trip him up. But he replied that the ear is quite non-linear. And he's absolutely right. Not that that was something I wasn't aware of, just that I had erroneously assumed that he was making an erroneous assumption. So my bad on that account.


se

 
But again it's a *testable*, and easily at that, assumption: one can easily make sines that a 3kHz apart, sum them up, and play them on whatever low-IMD system one has around, and see if you hear a 3kHz tone pop up. I don't, testing at various combos from 16kHz up to 25kHz or so (I don't know how fast the drop-off is on my Modi's freq response after 20k).

 

[Steve Eddy]

But again it's a *testable*, and easily at that, assumption: one can easily make sines that a 3kHz apart, sum them up, and play them on whatever low-IMD system one has around, and see if you hear a 3kHz tone pop up. I don't, testing at various combos from 16kHz up to 25kHz or so (I don't know how fast the drop-off is on my Modi's freq response after 20k).

I don't think you're quite understanding this.

If the hypothesis is that a real world trumpet producing harmonics at circa 80 kHz causes the ear, by virtue of its non-linearity, to produce intermod products in the audio band and possibly contributing to the sound of the trumpet, how does what you suggest test for this at all, let alone easily test for it?

se

 

[RRod]

I don't think you're quite understanding this.

If the hypothesis is that a real world trumpet producing harmonics at circa 80 kHz causes the ear, by virtue of its non-linearity, to produce intermod products in the audio band and possibly contributing to the sound of the trumpet, how does what you suggest test for this at all, let alone easily test for it?

se

 
So we wouldn't expect lower harmonic content (for instance a test of 22 + 25kHz) to do the same thing once it hits the ear? I can put an 80 and 83kHz tone together, but I have no way of guaranteeing my equipment is even producing the tones, so that's not a fair test on the stuff I have. But someone who does have equipment that can put out higher tones can do all kinds of test with summed sines to see if the expected non-linearity products crop up once they hit the ear. Why is a muted trumpet the only way to test this phenomenon?

 

[Steve Eddy]

So we wouldn't expect lower harmonic content (for instance a test of 22 + 25kHz) to do the same thing once it hits the ear?

But the hypothesis doesn't concern circa 20 kHz tones, but rather circa 80 kHz tones.

We got onto this after Analogsurviver cited some work by Boyk showing that a trumpet had a harmonic spectra that extended up to circa 80 kHz.

I can put an 80 and 83kHz tone together, but I have no way of guaranteeing my equipment is even producing the tones, so that's not a fair test on the stuff I have. But someone who does have equipment that can put out higher tones can do all kinds of test with summed sines to see if the expected non-linearity products crop up once they hit the ear.

You'd have to assure that the microphone and transducer were of very high linearity in order to test the hypothesis using such a method. That's where Analogsurviver and I are still at in this discussion.

Why is a muted trumpet the only way to test this phenomenon?

Because first of all, it's been shown that a trumpet can have harmonic content up to circa 80 kHz.

Second, the discussion is about recording and reproducing something like a trumpet such that the reproduction is consistent with how an actual trumpet sounds in real life. Analogsurviver suspects that those ultrasonic components need to be recorded and reproduced for that to be the case.

se

 

[MacacoDoSom]

 

produced by the ear? and is that good thing? I thought he wanted to hear what really happened when the horn was playing... the harmonics maybe produced by the room or whatever, but before being recorded...
if not so it make no sense...

He was talking about intermod products in the audible range. At first, I thought he was just confused and that he was erroneously assuming that just because something like a trumpet may have harmonic content at 80 kHz and 83 kHz that there would just magically be intermod product at 3 kHz, and that in order to reproduce that 3 kHz content, the recording would have to capture and the loudspeakers reproduce, those 80 and 83 kHz harmonics of the trumpet.

That of course isn't true. Those 80 and 83 kHz harmonics would have to be subject to some sort of non-linearity to produce a 3 kHz intermod product. So I asked him where was the non-linearity that would be responsible for that 3 kHz intermod product.

I thought I was being clever and was going to trip him up. But he replied that the ear is quite non-linear. And he's absolutely right. Not that that was something I wasn't aware of, just that I had erroneously assumed that he was making an erroneous assumption. So my bad on that account.

And that wasn't my only erroneous assumption.

I'd never really read any of his posts very thoroughly before, and just jumped on the bandwagon dismissing him as a troll.

But a recent event caused me to reconsider. It was when he was arguing cable capacitance vis a vis electrostatic headphones. After reconsidering, I concluded he was making some very good points.

So I sent him a PM and asked him if he would be up for a good old fashioned telephone conversation so I could get to know him a little better than would be possible from just posts in a forum.

He was and we had a very nice talk yesterday, which lasted for an hour or so before I had to break to take another call.

While I can't say I would agree with him on everything, I found him to be a genuinely nice guy who is actually quite knowledgeable, and I will no longer dismiss him as a troll. Instead, I will just exercise more patience with him, and look forward to our next telephone chat.

se

can't we call that 'ear induced harmonic distortion'?

 

[RRod]

But the hypothesis doesn't concern circa 20 kHz tones, but rather circa 80 kHz tones.

We got onto this after Analogsurviver cited some work by Boyk showing that a trumpet had a harmonic spectra that extended up to circa 80 kHz.
You'd have to assure that the microphone and transducer were of very high linearity in order to test the hypothesis using such a method. That's where Analogsurviver and I are still at in this discussion.
Because first of all, it's been shown that a trumpet can have harmonic content up to circa 80 kHz.

Second, the discussion is about recording and reproducing something like a trumpet such that the reproduction is consistent with how an actual trumpet sounds in real life. Analogsurviver suspects that those ultrasonic components need to be recorded and reproduced for that to be the case.

se

 
Yes I've seen that graph, and I see a bunch of harmonic content further down, so my question is why we wouldn't expect those harmonics to also interact with the non-linearity of the ear? They're also of higher magnitude, so I would think more likely to be producing artifacts that are audible. It's all good and fine if you must test a trumpet, but I don't see why test signals couldn't be used in a rigorous manner to understand audibility of these potential ear-produced tones.

 

[limpidglitch]

You'd have to assure that the microphone and transducer were of very high linearity in order to test the hypothesis using such a method. That's where Analogsurviver and I are still at in this discussion.
 

 
Why not play back the two ~80kHz test tones on two completely separate speaker systems?
 
You don't need extremely linear measurements to just confirm the presence of a given frequency on playback, and by using two separate systems you eliminate electronically induced IMD.

As RRod mentioned, checking wether the ear has these non-linearities at lower frequencies would be the obvious first test. I've also listened to 19+20kHz test tones on good regular equipment without ever hearing a thing.

 

[Steve Eddy]

can't we call that 'ear induced harmonic distortion'?

It would be intermodulation distortion, not harmonic distortion.

se