On Tuesday, November 1, 2016 at 4:20:29 PM UTC-7, Randy Yates wrote:

(snip)

> Agreed. The problem is that some people may reasonably argue that the
> current CD standard is too limited in resolution and/or sample rate. As
> Tim can attest, some people can hear up to 24 kHz. Also I think in some
> special borderline cases >16 bits resolution could be useful. So an
> updated audio standard may be reasonable (for some value of "reasonable"
> ha ha).

I am not so convinced, but it isn't easy to test.

If you have a 24kHz source that isn't perfect, anywhere along 
the way, you might get some other components, maybe 16kHz or 12kHz,
that were audible.

But more to the point, even if you can hear 24kHz alone, you won't
hear it, at normal levels, mixed in with other musical signals.

I have done (just) a few experiments, filtering symphony orchestra
recordings through low-pass filters.  There really isn't all that
much up there.

The popular 20Hz to 20kHz for audio equipment means that it should
be nice and flat over the range that you actually hear. 

The highest key on an 88 key piano is 4186Hz. There could be
some second or third harmonic around 8kHz or 12kHz, but still
a long way from 20kHz.  And most of the music is much lower
than that.

Seems to me that the only reason for higher sampling rates
is to get better results in the lower (but still high)
frequencies.  But well designed resampling digital filters
should be able to do everything we need.

Note that when CDs were first designed, the electronics
for fancy digital filters weren't around.  Even more, they
used gas lasers, as semiconductor lasers weren't ready.

I am not sure if they knew that diode lasers would come
along, and make for affordable CD players, though I suppose
mass production of gas lasers would have brought the costs
down enough.  

On Saturday, November 12, 2016 at 3:07:02 AM UTC-6, Steve Pope wrote:

> That's a good point.   Now with cannabis legalized in various
> USA states, the sensitivity of golden-ear listeners has just exhibited
> a step function.  (Not sure which way, but still.)

Some of us golden-ear (urg; I dislike that term) listeners abstain.

Max  <Max@sorrynope.com> wrote:

>One of the problems in the high end audio marketplace is that they're
>now stuck with conversions that were often done very poorly (Sony
>PCM-1630's used for tons of CD conversions)..  

Yes.  The Sony PCM units were creating grumbling and complaints
in the late 70's while I was still in the industry, with one
engineer of my acquaintance banishing them from a major studio.

The CDA format was underdesigned, but perhaps for good economic 
reasons -- whereas using an underdesigned digitization/storage
medium in between the master tape and CD manufacturing is
just plain dumb.  

Steve

On Fri, 11 Nov 2016 13:27:38 +0000 (UTC), spope33@speedymail.org
(Steve Pope) wrote:

>If Pono gained traction, such that most devices used it in
>the intended way, then great.  Don't hold your breath.

One of the problems in the high end audio marketplace is that they're
now stuck with conversions that were often done very poorly (Sony
PCM-1630's used for tons of CD conversions)..  The original analog
master tapes have crumbled, become sticky, or sadly, often just
discarded.  Some notorious travesties committed by large companies who
didn't want to keep storing the original analog tapes.

I'm happy to see new recordings done at 192/24. They can always be
down-sampled, so any new compression scheme that minimizes artifacts
(like Meridian) can start with relatively pristine recordings.  Good
by me.

I've been seeing quite a bit of interest in 192k/24 at audio shows, so
I wouldn't be at all surprised to see it used more often.  Recording
software and plugin vendors are adapting.  I think that 44.1k may be
in trouble, given the drop in CD sales.  Not much reason to use that
rate unless the music is going to CD, or someone is really desperate
to save money on drive space.

Steve Pope wrote:
> Max  <Max@sorrynope.com> wrote:
>
>> On Wed, 2 Nov 2016 19:24:43 -0500, Les Cargill
>
>>> It also doesn't help that you get high-profile folks like Neil Young
>>> spouting nonsense about Pono.
>
>> That's your own judgement.  Not shared universally.
>
> I was not aware of Pono, so looked it up.  Nice in theory --
> maintaining a 192 Ks/sec sample rate through the whole
> chain, such that no steep filters are ever needed.
>
> The problem is, this rules out the ability of plugging in
> and using most equipments -- effects and whatnot.  So it's a
> great way of getting reference recordings to golden ear
> listeners, but for commercial product, it is too limited.
>

I think it's weirder than that - Young is obviously getting
on in years, and he wants his legacy to be preserved through
a medium like this.

I can't say I blame him for that. He just doesn't appear
to grok sampling theory.

I just hope he's watched what's happened with Gail and Frank Zappa
and the unfortunate goings on there, and is able to solve some of the
business problems.

> If Pono gained traction, such that most devices used it in
> the intended way, then great.  Don't hold your breath.
>

Bingo.

>
> S.
>

-- 
Les Cargill

Max wrote:
> On Wed, 9 Nov 2016 18:31:34 -0600, Les Cargill
> <lcargill99@comcast.com> wrote:
>
>> Max wrote:
>>> On Wed, 2 Nov 2016 19:24:43 -0500, Les Cargill
>>> <lcargill99@comcast.com> wrote:
>
>>>> Okay - for *end playback*, 16/44.1k is extremely entrenched and
>>>> perfectly adequate.
>>>
>>> For the non-demanding ear, 128 bps MP3 is 'perfectly adequate.'  It
>>> depends on whether you're sensitive to the odd-sounding artifacts.
>
>> I can't consider 128k MP3 adequate for anything. You can diff the
>> waveforms; the difference is a lot of signal. 320k even has *some*
>> difference. It's more subtle.
>
> Les, The point was that some can tell, some can't.  In this case, you
> can.  You could acknowlege that the same is possible re 44.1.


The difference in "rough order of magnitude of the difference" is
pretty large. 128k is very "noisy", so ...

> Again, this is not about the ability to hear 20Khz--it's about how
> many odd artifacts are introduced in the encode/decode process.
>
>
>>> It sounds like your mind is already set, but if not, look into
>>> research being done by Meridian, including new formats that are
>>> intended to be more ear-friendly.
>
>> I will - I didn't mean to sound closed-minded. I have read some of their
>> stuff. It's a bit of a slog.
>
> Meridian spun off MQA.com from their newest compression technology.
> Those are not magic wire merchants--they are scientists and
> psychoacousticians.

Yep. Serious guys.

> The MQA patents and other info can be found, and
> may be helpful for sketching in missing parts of the puzzle.  It's not
> 192/24, but it's partway there, with good explanations from Bob
> Stuart.  MQA is being considered as a new standard music format by
> some of the major music companies.
>

-- 
Les Cargill

radams2000@gmail.com wrote:
> Most of the concern over pre-ringing occurs in the studio, where you
> may have 5 or more dsp sound processing boxes connected in series
> using analog I/O.  This increases the pre-ringing period from about
> 0.5 ms for a single box up to 5ms for a cascade of 10 units.

Excellent point. 5 ms sounds pretty likely to be audible. Although
if they're actually in series, you're back to .5 msec, and likewise
in parallel.

I presume you mean "digital effects with A/D-D-A that are connected 
analog", like a Digitech box.

FWIW, many of those have S/PDIF ( and so do most interfaces ) which
makes all that go away :)

> Also
> some DAW software may optionally provide super-steep filters for
> sample-rate conversion, which may put you in the danger category.
>

Yeah; SRC is just one of those swamps. I've played with it in an
offline-not-realtime-fashion and the approach I like best is to find a
sampling rate that is a harmonic of both sapling rates, then downsample, 
  so there's only the one filter at the end. And
I tended to just use a fancier IIR then.

> Some a/d converters now use minimum-phase decimation filters instead
> of linear-phase filters, which reduces the pre-ringing at the expense
> of more post-ringing which tends to be temporally masked. A good idea
> IMHO; it's too bad the industry adopted the term "linear-phase"
> because who doesn't want linear ?
>

FWIW, I perpetually confuse "minimum phase" and "linear phase" anyway
:)

> Bob
>


-- 
Les Cargill

<makolber@yahoo.com> wrote:

>> I cannot say, however, what pre-ringing might sounds like. It'd take
>> some serious consideration to design a test to find out.

>this is an interesting point

>pre or post ringing at 22kHz would be difficult for many people to hear.

>So as an experiment, scale everything (the filter cutoff freq) down by a
>factor of 5 or 10.

>Ringing at 2 or 4 kHz should be easy to hear.

>It would be an interesting experiment to see if you can hear it at 10 kHz even.
>

Thought I had replied to this but apparently not.

To experiment with whether pre-ringing is audible, you want
to vary the steepness of the cutoff, not the corner frequency.
You can leave the corner frequency at some convenient value
such as 20 KHz.

Steve

<gyansorova@gmail.com> wrote:

>Quantization noise is lower too. Ok so maybe you can't hear the
>difference but I am sure those golden ear hippies that listen to old 33
>records can

That's a good point.   Now with cannabis legalized in various
USA states, the sensitivity of golden-ear listeners has just exhibited
a step function.  (Not sure which way, but still.)

S.

Max  <Max@sorrynope.com> wrote:

>On Wed, 2 Nov 2016 19:24:43 -0500, Les Cargill

>>It also doesn't help that you get high-profile folks like Neil Young 
>>spouting nonsense about Pono.

>That's your own judgement.  Not shared universally.

I was not aware of Pono, so looked it up.  Nice in theory --
maintaining a 192 Ks/sec sample rate through the whole
chain, such that no steep filters are ever needed.

The problem is, this rules out the ability of plugging in
and using most equipments -- effects and whatnot.  So it's a 
great way of getting reference recordings to golden ear
listeners, but for commercial product, it is too limited.

If Pono gained traction, such that most devices used it in
the intended way, then great.  Don't hold your breath.


S.