For all the hifi skeptics....

[Anonymous]

You may well be correct, but there is a growing body of opinion that believe the frequencies we can't hear, have an effect on those we can.

No there isn't. More nonsense I am afraid. There was a paper by Tsutomo Oohashi sometime back that maintained that humans responded to hypersonic stimulus. The paper has been discreditied in many subsequent studies. Unfortunately, it doesn't stop people linking to the original paper, or believing it.

http://en.wikipedia.org/wiki/Hypersonic_effect

Would it be fair to infer from this, that you think some of the major speaker companies have spent a lot of time and money, producing very high frequency tweeters as a marketing ploy?.....either that or their thinking is flawed. This is not having a go, it's just that I'm interested in your view. Edit. Maybe someone from the speaker manufacturers on here, would like to comment.

The argument, if there is one, is that by having tranducers of the quality to be able to reproduce sounds above the audible range, the performance of these transducers in the audible range is better than transducers that can only just make it to 20KHz. A car analogy is owning a Ferrari that can do 175mph when the speed limit is 70. The extra performance, which never gets used, improves the handling and braking in the speed range that does get used.

Worth remembering that CDs are band limited to 20KHz. There is nothing above 20KHz to reproduce.

 

[6th.replicant]

Surely hi-res vs 20kHz is not all about inaudible dog-range upper frequencies?

I've just compared 16/44.1 and 24/96 versions of the same download of Rumours, played via iTunes/MBP -> USB -> DAC.

The 24/96 has much deeper and tighter bass, IMHO.

Similarly, if a Blu-ray movie has Dolby Digital and (uncompressed) DTS-HD Master Audio versions of the soundtrack, the latter always has significantly more sub' oomph.

So, hi-res has higher highs and lower lows

 

[CnoEvil]

Worth remembering that CDs are band limited to 20KHz. There is nothing above 20KHz to reproduce.

That is true, but CDs are on the decline, and hi-res audio in both AV and 2 channel is on the rise...so I suppose that is the logic behind what a lot of speaker manufacturers are doing.

 

[6th.replicant]

...A car analogy is owning a Ferrari that can do 175mph when the speed limit is 70. The extra performance, which never gets used, improves the handling and braking in the speed range that does get used...

Never put that theory to the test in a 348... :O

 

[Anonymous]

Surely hi-res vs 20kHz is not all about inaudible dog-range upper frequencies?

I've just compared 16/44.1 and 24/96 versions of the same download of Rumours, played via iTunes/MBP -> USB -> DAC.

The 24/96 has much deeper and tighter bass, IMHO.

Similarly, if a Blu-ray movie has Dolby Digital and (uncompressed) DTS-HD Master Audio versions of the soundtrack, the latter always has significantly more sub' oomph.

So, hi-res has higher highs and lower lows

That sounds like it may be different recordings. Have you tried downsampling the high res version?

There is no reason for the high res version to have "deeper bass". It makes no sense when the CD quality version is only limited at 20 KHz and above.

 

[Overdose]

I'm not sure what the frequency is, but in the old days, you could walk into a room and sense if a CRT television was switched on, even if you couldn't see it.

The flyback transformer at around 15.625KHz?

Definitely within the audible range of human hearing and I can certainly hear it and other high frequency equipment whine too, it's a right pain.

To the OP, I'm not sure that I believe in all this hi-fi scepticism.

 

[Anonymous]

I do agree that even though we can't hear these frequencies, we can sense them. I'm not sure what the frequency is, but in the old days, you could walk into a room and sense if a CRT television was switched on, even if you couldn't see it.

PAL CRT line flyback frequency is 15.625KHz. The line flyback transformer often acted as a transducer and gave the TV its characteristic whistle.

I am afraid I have still been unable to find any reliable analysis that indicates that humans can sense hypersonic soundwaves. Post a link if you come across a real peer reviewed study - I would be interested.

My speakers are within plus/minus 3dB up to 22KHz. I can't hear a damn thing above 14KHz, nor am I able to 'sense' the sound either. Damn shame really, now I can afford some decent gear, I am too old to appreciate it. Thats life I guess.

 

[MajorFubar]

The flyback transformer at around 15.625KHz?

Definitely within the audible range of human hearing and I can certainly hear it and other high frequency equipment whine too, it's a right pain.

If you're over 40 and you can still hear that, pat yourself on the back . When I was a teenager my hearing surpassed 22kHz. I'm now on the wrong side of 40 and with hard concentration I can just about hear 14kHz

 

[6th.replicant]

Surely hi-res vs 20kHz is not all about inaudible dog-range upper frequencies?

I've just compared 16/44.1 and 24/96 versions of the same download of Rumours, played via iTunes/MBP -> USB -> DAC.

The 24/96 has much deeper and tighter bass, IMHO.

Similarly, if a Blu-ray movie has Dolby Digital and (uncompressed) DTS-HD Master Audio versions of the soundtrack, the latter always has significantly more sub' oomph.

So, hi-res has higher highs and lower lows

That sounds like it may be different recordings. Have you tried downsampling the high res version?

There is no reason for the high res version to have "deeper bass". It makes no sense when the CD quality version is only limited at 20 KHz and above.

Umm, the clue is in the phrase "I've just compared 16/44.1 and 24/96 versions[/b] of the same download[/b] of Rumours"

Or to be more precise, the 16/44.1 is the downsample (for my iPod) taken from the 24/96 of the same recording.

Also just tried comparing the Redbook 16/44.1 and DSD layers of Ziggy Stardust and Dark Side Of The Moon hybrid SACDs.

Granted, the 16/44.1 was via iTunes/DAC and the DSD via CD37, but it's the same amps, speakers and cables - and there's an Arcam DAC in the loop in both instances.

Both Ziggy and DSOTM's DSD hi-res have deeper and tighter bass compared to 16/44.1 versions, of the same recording

 

[Anonymous]

Worth remembering that CDs are band limited to 20KHz. There is nothing above 20KHz to reproduce.

That is true, but CDs are on the decline, and hi-res audio in both AV and 2 channel is on the rise...so I suppose that is the logic behind what a lot of speaker manufacturers are doing.

The point of hi res is that it samples the audio band (up to 20KHz) at a multiple of the Nyquist frequency, not that it increases the upper frequency limit of the sampled audio band. Have you seen anything that suggests that hires is aiming to reproduce audio over 20KHz?

 

[Anonymous]

Surely hi-res vs 20kHz is not all about inaudible dog-range upper frequencies?

I've just compared 16/44.1 and 24/96 versions of the same download of Rumours, played via iTunes/MBP -> USB -> DAC.

The 24/96 has much deeper and tighter bass, IMHO.

Similarly, if a Blu-ray movie has Dolby Digital and (uncompressed) DTS-HD Master Audio versions of the soundtrack, the latter always has significantly more sub' oomph.

So, hi-res has higher highs and lower lows

That sounds like it may be different recordings. Have you tried downsampling the high res version?

There is no reason for the high res version to have "deeper bass". It makes no sense when the CD quality version is only limited at 20 KHz and above.

Umm, the clue is in the phrase "I've just compared 16/44.1 and 24/96 versions[/b] of the same download[/b] of Rumours"

Or to be more precise, the 16/44.1 is the downsample (for my iPod) taken from the 24/96 of the same recording.

Also just tried comparing the Redbook 16/44.1 and DSD layers of Ziggy Stardust and Dark Side Of The Moon hybrid SACDs.

Granted, the 16/44.1 was via iTunes/DAC and the DSD via CD37, but it's the same amps, speakers and cables - and there's an Arcam DAC in the loop in both instances.

Both Ziggy and DSOTM's DSD hi-res have deeper and tighter bass compared to 16/44.1 versions, of the same recording

Snivilisationism is quite correct, sampling rate and bit depth changes between redbook and hi res will not effect bass. If you can hear a difference, then something else in the changes you are making is causing it.

 

[CnoEvil]

]

The point of hi res is that it samples the audio band (up to 20KHz) at a multiple of the Nyquist frequency, not that it increases the upper frequency limit of the sampled audio band. Have you seen anything that suggests that hires is aiming to reproduce audio over 20KHz?

I'm just trying to understand why speaker companies are making tweeters that go as high as 100 KHz (MA Platinum), if there's nothing to reproduce at that frequency. :?

I am only an interested enthusiast, not a recording engineer, so I'll leave technical explanations to those more knowledgable than myself.

Cno

 

[Overdose]

The flyback transformer at around 15.625KHz?

Definitely within the audible range of human hearing and I can certainly hear it and other high frequency equipment whine too, it's a right pain.

If you're over 40 and you can still hear that, pat yourself on the back . When I was a teenager my hearing surpassed 22kHz. I'm now on the wrong side of 40 and with hard concentration I can just about hear 14kHz

I might be in the ballpark of 40

I did one of those not so scientific hearing frequency tests and as I recall, my hearing drops off at 16KHz, so it won't be long before I can comfortably go back to CRT TVs.

 

[6th.replicant]

... Snivilisationism is quite correct, sampling rate and bit depth changes between redbook and hi res will not effect bass. If you can hear a difference, then something else in the changes you are making is causing it.

I'm intrigued. So why, when swapping back and forth from a Blu-ray's compressed Dolby Digital and uncompressed DTS-HD Master' (ie hi-res) layers is the sub's output deeper with the latter? :?

 

[Anonymous]

The point of hi res is that it samples the audio band (up to 20KHz) at a multiple of the Nyquist frequency, not that it increases the upper frequency limit of the sampled audio band. Have you seen anything that suggests that hires is aiming to reproduce audio over 20KHz

Actually, practically all ADCs process the analog signal at large multiples of the Nyquist frequency, regardless of the targeted sample rate. The higher sample rate in files means you need more digital processing but require a less complex analog stage. Given that digital processing gets faster and cheaper by the minute, the move makes mostly sense from an economic point of view.

As for aiming to reproduce >20kHz, I think the jury's still out on that one. To keep with the theme of the thread: it wouldn't be the first time that product marketing defies common sense and/or science (cue Spinal Tap reference).

I'm just trying to understand why speaker companies are making tweeters that go as high as 100 KHz (MA Platinum), if there's nothing to reproduce at that frequency

I'd be more interested in who they are producing such stuff for. As it's not going to benefit human beings...

 

[nopiano]

I'm with Cno on this one.

Many musical instruments have overtones beyound whatever you think your upper hearing limit is. Those frequencies are part of the waveform we hear 'live'. If they are missing when reproduced then the waveform is different.

If decent audio gear is trying to reporoduce something close to the original then it makes sense to me to preserve those frequencies if possible (and assuming they don't cause other problems). Being able to detect, say, a single 20kHz tone, is surely not the same as being unable to hear its effect on a 15kHz and 10kHz one, when all three are present together. Obviously real music is much more complex than that, so why remove bits of it if you needn't?

 

[naughty573]

Ok, I'll give you that, but it sure as heck is strong evidence against the "all amps sound the same" crowd. There have been numerous blind listening tests that "prove" that all amps sound the same.

Interesting ..... who is this "crowd" that claims this? because to tell you the truth i have not really heard of this claim

Though i have definitely heard many claims to the effect that when comparing two or more amplifiers if each one was restricted to the identical power level of the lowest powered one, the differences then become inaudible to the human ear or not so easily percieved to the extent that having one over the other would not make much of a difference

it is easy to see how this could be construed as a claim that all amplifiers sound the same but because all amplifiers do not have the same levels of power they obviously do not sound the same

 

[Andrew17321]

Music is not simply composed of a single constant frequency.

As soon as more than one frequency is involved the phases between the different frequency signals becomes extremely important – and our ears are very good at detecting the phase of signals: it is how we detect the direction of sounds we hear.

When a symbol is struck we don't hear constant frequency signals, we hear a sound, which, theoretically, a signal processor could deconstruct into a a quickly changing composition of frequencies ranging well beyond 100kHz. We can hear and recognize these transient sounds.

It is no use just saying that we cannot hear pure constant frequencies beyond 20,000 Hz (which is true for most of us) because hearing is not limited to detecting constant frequencies. Frequency response is only part of the story. (Just as stereoscopic vision is only part of our ability to see 3D, and why watching current 3D films is somewhat unsatisfactory.)

Andrew

 

[Andrew17321]

Can I suggest a simple experiment.

Go somewhere you can see and hear birds. Close your eyes and face a bird that is singing. Open your eyes and see how much you have to turn to directly face this bird. How far have your ears moved relative to each other in so doing? For most people I reckon it will be less than 1 cm.

Now sound travels at a bit over 330 m/s, ie 33,000 cm/s. So if you have had to move your ears by 1 cm you have detected a time difference of 1 part in 33,000 of a second.

You may not hear constant frequencies above 20,000 Hz but your ears can react to sounds faster.

Andrew

 

[altruistic.lemon]

Music is not simply composed of a single constant frequency.

As soon as more than one frequency is involved the phases between the different frequency signals becomes extremely important – and our ears are very good at detecting the phase of signals: it is how we detect the direction of sounds we hear.

When a symbol is struck we don't hear constant frequency signals, we hear a sound, which, theoretically, a signal processor could deconstruct into a a quickly changing composition of frequencies ranging well beyond 100kHz. We can hear and recognize these transient sounds.

It is no use just saying that we cannot hear pure constant frequencies beyond 20,000 Hz (which is true for most of us) because hearing is not limited to detecting constant frequencies. Frequency response is only part of the story. (Just as stereoscopic vision is only part of our ability to see 3D, and why watching current 3D films is somewhat unsatisfactory.)

Andrew

Don't think the beings on this planet can! Who says this? Also, which instruments go beyond 20khz? Got a feeling only the human voice can. Most of the rest peg out at 14khz.or so.

As to 100khz tweeters - what else in the chain can go so high? CD players can't, neither can Record players, so it's a pointless exercise.

 

[oldric_naubhoff]

Music is not simply composed of a single constant frequency.

As soon as more than one frequency is involved the phases between the different frequency signals becomes extremely important – and our ears are very good at detecting the phase of signals: it is how we detect the direction of sounds we hear.

When a symbol is struck we don't hear constant frequency signals, we hear a sound, which, theoretically, a signal processor could deconstruct into a a quickly changing composition of frequencies ranging well beyond 100kHz. We can hear and recognize these transient sounds.

It is no use just saying that we cannot hear pure constant frequencies beyond 20,000 Hz (which is true for most of us) because hearing is not limited to detecting constant frequencies. Frequency response is only part of the story. (Just as stereoscopic vision is only part of our ability to see 3D, and why watching current 3D films is somewhat unsatisfactory.)

Andrew

I think that's very interesting point and I think it's very true. but what bugs me is that if all the frequencies created by an instrument interact and influence each other and then interact and influence with all frequencies created by all remaining instruments in the venue to form what we can hear as live performance in our brains through our ears, and then if a mic is capturing this mix of all inter-relating frequencies, shouldn't it be enough to feel the realism of performance through 20 Hz - 20 000 Hz medium? I mean, what is then recreated through speakers should be the end product of what we would hear at live performance anyway, shouldn't it?

P.S. writing those words I assume a perfect audio system which is able to capture sounds accurately and then recreate them realistically as well, obviously. I know such thing is not yet invented but it's just hypothetical wondering.

 

[Anonymous]

Umm, the clue is in the phrase "I've just compared 16/44.1 and 24/96 versions[/b] of the same download[/b] of Rumours"

Or to be more precise, the 16/44.1 is the downsample (for my iPod) taken from the 24/96 of the same recording.

Also just tried comparing the Redbook 16/44.1 and DSD layers of Ziggy Stardust and Dark Side Of The Moon hybrid SACDs.

Granted, the 16/44.1 was via iTunes/DAC and the DSD via CD37, but it's the same amps, speakers and cables - and there's an Arcam DAC in the loop in both instances.

Ok. It's just I know of someone who tried it with "Downloads from the same site" which could be claimed as "same download", which it possibly/probably isn't.

Either way, the bass shouldn't be affected. An interesting experiment here could be...
Take Audacity.

Load up each file.

Cut out a few seconds of audio (The same for each) (If you try the whole song it will cut some out and may be different)

Show the spectrum analysis (change the size to 8192 and use "log" for frequency). You should get a nice clear graph of exactly what's going on from 0 Hz onwards). It would be interesting if there was a difference.

Also, what I've found in some "high res" files, is that while there is information above 20 KHz, it doesn't look "real". ie it varies wildly below, but looks like a smooth "fake" curve above. I'm not sure why this should be.

 

[Anonymous]

Can I suggest a simple experiment.

Go somewhere you can see and hear birds. Close your eyes and face a bird that is singing. Open your eyes and see how much you have to turn to directly face this bird. How far have your ears moved relative to each other in so doing? For most people I reckon it will be less than 1 cm.

Now sound travels at a bit over 330 m/s, ie 33,000 cm/s. So if you have had to move your ears by 1 cm you have detected a time difference of 1 part in 33,000 of a second.

You may not hear constant frequencies above 20,000 Hz but your ears can react to sounds faster.

Andrew

Andrew,

I am afraid you are a little adrift here. There is no evidence I can find for 'reacting to sounds faster' - can you link to a report?

Human sound localisation at low frequencies is done using a 'first to arrive' (phase) mechanism, at higher frequencies it is the comparison of the relative loudness of the sound in the two ears. In your bird example, turning your head reduces the volume in one ear and increases it in the other allowing the brain to figure out the lateral shift.

The balance control on your hifi does not alter relative phase, it changes relative volume of the two speakers to create the impression that the centre of the soundstage has moved by altering the relative sound volume in your ears.

 

[Anonymous]

Music is not simply composed of a single constant frequency.

As soon as more than one frequency is involved the phases between the different frequency signals becomes extremely important – and our ears are very good at detecting the phase of signals: it is how we detect the direction of sounds we hear.

When a symbol is struck we don't hear constant frequency signals, we hear a sound, which, theoretically, a signal processor could deconstruct into a a quickly changing composition of frequencies ranging well beyond 100kHz. We can hear and recognize these transient sounds.

It is no use just saying that we cannot hear pure constant frequencies beyond 20,000 Hz (which is true for most of us) because hearing is not limited to detecting constant frequencies. Frequency response is only part of the story. (Just as stereoscopic vision is only part of our ability to see 3D, and why watching current 3D films is somewhat unsatisfactory.)

Andrew

Actually, our ears are remarkably insensitive to phase shift.

Dr Floyd Toole:

" It turns out that, within very generous tolerances, humans are insensitive to phase shifts. Under carefully contrived circumstances, special signals auditioned in anechoic conditions, or through headphones, people have heard slight differences. However, even these limited results have failed to provide clear evidence of a 'preference' for a lack of phase shift. When auditioned in real rooms, these differences disappear.. ."

A complex audio signal can be thought of as a mix of frequencies of different amplitude and phase. Our ears don't do much of a job of discerning phase, but they are pretty good at amplitude and frequency. Our ears run out of sensitivity at around 20KHz when young, tailing off quite rapidly with age.

It doesn't matter what audio signals exist outside of our hearing range, we can't hear them. Any harmonic components are also lost to us, we can't hear them.

While a cymbal's complex waveform undeniably has components well above 20KHz, it doesn't matter, because we can't hear them.

Using your eye analogy, you cannot see light in the ultraviolet, or infra red. Do you think TVs should reproduce these waveforms, even though we can't see them, to improve the picture?

 

[MajorFubar]

As to 100khz tweeters - what else in the chain can go so high? CD players can't, neither can Record players, so it's a pointless exercise.

Commonly not, but it is possible. Frequencies of up to 122 kHz have been experimentally cut on records. CD4 records (quadraphonic) contained frequencies up to 50 kHz to encode what we would now call the surround channels.