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Posted
13 minutes ago, acg said:

 

Examples?

 

 

You are talking about a unit using compression to remove tape hiss in 1993...we've come a long way since then.

Examples of players I use going further with resolution are Pioneer PDS 904 ( and further still with changes to 78x and 79x ) and likewise Marantz CD7300

 

Re the DBX you are not understanding just how good companding is, it is how almost all recordings since 1966 have been recorded. It is compression, then what you omit,  being expansion, which causes 20db of added dynamic range and a silent noise floor. Proof is in the pudding you can spend mega $ on trying to evoke dynamic range from analog electronics, or get the same result with real time companding.   

Posted
4 hours ago, stereo coffee said:

But limiting such frequencies has good opinion , that such limiting irreversibly changes,  the frequencies we do hear, much for the worse.

It is easy to check whether this is happening or not.   ;) 

 

If you are changing the frequencies below 20khz, then that is bad.... and you should change what it is you're doing.

 

 

  • Like 1
Posted
6 minutes ago, davewantsmoore said:

It is easy to check whether this is happening or not.   ;) 

 

If you are changing the frequencies below 20khz, then that is bad.... and you should change what it is you're doing.

 

 

Considering the medium already contains limitations of bandwidth, it is already happening 😊

What the opinion expresses is for the limitation to be removed to find what is possible.

Posted
22 minutes ago, stereo coffee said:

Examples of players I use going further with resolution are Pioneer PDS 904 ( and further still with changes to 78x and 79x ) and likewise Marantz CD7300

 

So you are talking cd players in a thread about hi-res.

 

 

22 minutes ago, stereo coffee said:

Re the DBX you are not understanding just how good companding is, it is how almost all recordings since 1966 have been recorded. It is compression, then what you omit,  being expansion, which causes 20db of added dynamic range and a silent noise floor. Proof is in the pudding you can spend mega $ on trying to evoke dynamic range from analog electronics, or get the same result with real time companding. 

 

But this thread is about playback, not recording/mixing. 

 

 

Here's the simple truth...

 

Our rooms need circa 11-12 bits of dynamic range to play at live concert spl (fortissmo 105dB minus room ambient volume 40dB).  Redbook has 16 bits which is plenty to allow for headroom and quiet recordings so if your playback system gain structure is not munted then all is good there and 24 bit recordings are not going to be able to play any quieter sounds into your room i.e. no more resolution.

 

Higher sample rates also do not play quieter sounds in your room, only higher frequency sounds (assuming your playback can reproduce them of course...most cannot) which are not audible...otherwise the playback is identical.

 

However, there are ways for hi-res to sound different to Redbook if your dac architecture prefers these files but that is not the difference between redbook and hi-res file formats, that is the difference in your dac and everyone is able to sidestep needing hi-res files in this circumstance by upsampling the file before sending it to the dac.

 

Only buy hi-res files for the different mastering (if it is different at all of course) because it brings nothing else to the table.

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Posted
11 minutes ago, stereo coffee said:

Considering the medium already contains limitations of bandwidth, it is already happening 😊

It's hard for me to understand what you are saying.....

 

... but if what you mean is that "removing frequencies above 20khz is definitely altering frequencies below 20khz" ..... then you are wrong.   These frequencies (below 20khz) CAN be removed without any alteration (to above 20khz).   It depends on how you do it.

  • Like 3

Posted
11 minutes ago, acg said:

 

So you are talking cd players in a thread about hi-res.

 

 

 

But this thread is about playback, not recording/mixing. 

 

 

Here's the simple truth...

 

 

Re reading the OP you are right, I was distracted by 16 bit applying to CD players.

 

Re DBX it is used as a playback device, the penny will drop when you use one

Posted (edited)
1 hour ago, stereo coffee said:

Re DBX it is used as a playback device, the penny will drop when you use one

 

No its not.  It has to be used on and process the original recording, and at replay to reverse the compression.

 

It's was just a competitor for Dolby noise reduction, primarily for tape systems.

 

Unless you have used it with your own tape recordings, there are virtually no sources of dbx encoded material.

 

It wasn't a completely transparent process.  I would certainly stick with straight dithered 16bit in comparison.

Edited by March Audio
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Posted
15 minutes ago, March Audio said:

No its not.  It has to be used on and process the original recording, and at replay to reverse the compression.

Presumably if it’s used at playback on material that was not recorded with it then it's acting like some sort of effects box?

Posted (edited)
4 minutes ago, sir sanders zingmore said:

Presumably if it’s used at playback on material that was not recorded with it then it's acting like some sort of effects box?

Yep. It will totally mess up the sound if used on non dbx encoded recordings.

Edited by March Audio
  • Like 2
Posted
2 minutes ago, davewantsmoore said:

It's hard for me to understand what you are saying.....

 

... but if what you mean is that "removing frequencies above 20khz is definitely altering frequencies below 20khz" ..... then you are wrong.   These frequencies (below 20khz) CAN be removed without any alteration (to above 20khz).   It depends on how you do it.

It is not an experience either of us can enjoy to know what exactly happens, as economic thoughts with digital, are already in place. But  if we look at what actual recordings rather than media subsequently bandwidth limited released, then we see lot's of effort being understood by engineers  to preserve as much frequency as possible from the recording event, and not being constrained. 

 

Not "removing frequencies above 20khz " , rather limiting bandwidth , where those naturally occurring frequencies already abound, and are part of the instruments capability.

12 minutes ago, March Audio said:

 

No its not.  It has to be used on and process the original recording, and at replay to reverse the compression.

 

It's was just a competitor for Dolby noise reduction, primarily for tape systems.

 

Unless you have used it with your own tape recordings, there are no sources of dbx encoded material.

 

It wasn't a completely transparent process.  I would certainly stick with straight dithered 16bit in comparison.

Looks like you have not used one,  as you would then know it can be used real time. To do so you link the two internal circuit boards with rear panel connectors.  

 

 

Posted (edited)
15 hours ago, stereo coffee said:

then we see lot's of effort being understood by engineers  to preserve as much frequency as possible from the recording event, and not being constrained. 

 

Not true.  Few mics used on typical music recordings will do well above 30kHz.  I suggest you take a look at a few hi res recordings and see that most of the time there's little but noise going on above 25kHz.

 

15 hours ago, stereo coffee said:

Looks like you have not used one,  as you would then know it can be used real time. To do so you link the two internal circuit boards with rear panel connectors

 

I know exactly how they are used thanks.

 

They need to be used *through* a "noisy" medium, ie tape, but could be used on something like an FM radio link. 

 

You can't just plug it into a cd player output, go through an encode and decode and expect benefits.  

 

Quite the contrary would happen. You would just add the inherent distortions of dbx encode / decode process.

Edited by March Audio
Posted
12 minutes ago, March Audio said:

 

Not true.  Few mics will do well above 30kHz.  I suggest you take a look at a few hi res recordings and see that most of the time there's little but noise going on above 25kHz.

 

 

I know exactly how they are used thanks.

 

They need to be used *through* a "noisy" medium, ie tape.  You can't just plug it into a cd player go through an encode and decode and expect benefits.  

Until you try it.

Posted
1 hour ago, davewantsmoore said:

It's hard for me to understand what you are saying.....

Well I'm glad I'm not the only one... Same in a few other topics too..

  • Like 1
Posted (edited)
8 hours ago, Dingbat said:

I think the idea behind sampling rates higher than 20kHz is not that it's beyond human hearing, it's the interpolation in the digital signal.

 

It is a common misconception; that we can miss important audible signal "jiggles" in between the sample points.  Therefore by sampling faster we can capture them and improve audio quality. Unfortunately, whilst that seems intuitively correct, it's not.

 

Sampling theorem is proven to capture all the signal information below the nyquist point, half the sample rate.

 

So 44.1 kHz sample rate is perfectly adequate for our hearing range.  If there are signal "wiggles" in between samples they are by definition above 22.05 kHz.  They are higher frequencies which we can't hear.  So for our hearing range we benefit nothing by going up to 96kHz.

 

This brilliant video explains it (and busts a few other myths) much better than I can.

 

 

 

 

Edited by March Audio
  • Like 2
Posted
1 minute ago, March Audio said:

So 44.1 kHz sample rate is perfectly adequate for our hearing range.  ...  So for our hearing range we benefit nothing by going up to 96kHz.

 

This brilliant video explains it much better than I can.

 

 

 

So, yet another "dog on the Internet" is the only source of truth, Alan?  :classic_tongue:

 

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Posted
20 minutes ago, andyr said:

 

So, yet another "dog on the Internet" is the only source of truth, Alan?  :classic_tongue:

 


not sure what you mean Andy, but I’ve always found that video to be a very good explanation for why the “stair step” analogy of sampling is incorrect. 

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Posted
1 minute ago, sir sanders zingmore said:

not sure what you mean Andy, but I’ve always found that video to be a very good explanation for why the “stair step” analogy of sampling is incorrect. 

 

I'm sure that's a valid comment, Trev - it's just that I:

  1. prefer reading to watching (so cannot bring myself to watch YT videos)
  2. and, unlike some, do not accept as gospel, something that I see on the Internet.

 

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Posted
6 minutes ago, sir sanders zingmore said:


not sure what you mean Andy, but I’ve always found that video to be a very good explanation for why the “stair step” analogy of sampling is incorrect. 

And a multitude of other digital myths such as time resolution being related to sample rate.

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Posted
3 minutes ago, andyr said:

 

I'm sure that's a valid comment, Trev - it's just that I:

  1. prefer reading to watching (so cannot bring myself to watch YT videos)
  2. and, unlike some, do not accept as gospel, something that I see on the Internet.

 

In that case, have a read about how sampling works (if you haven’t already). The step analogy is wrong (not that you were claiming it was right). 

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Posted (edited)
9 minutes ago, andyr said:

 

  1. and, unlike some, do not accept as gospel, something that I see on the Internet.

 

 

If there is some technical point you don't beleive or understand in the video, just say and we can discuss.

 

Some of the info is counter intuitive, but it's all proven fact.

Edited by March Audio
Posted
3 minutes ago, March Audio said:

And a multitude of other digital myths such as time resolution being related to sample rate.

 

Re. this so-called 'digital myth' Alan ... it seems to me that a similar concept is the sound of 45rpm LPs vs. the standard 33rpm LPs.

 

I happen to have an LP which has just one track on each side - one side to be played at 33.333rpm ... the other at 45rpm.  It is quite obvious that the SQ of the 45rpm side is better than the that of the 33rpm side.

 

To me ... 45rpm means "a higher sampling rate".

 

Sure, I have lots of other LPs where I have both a 33rpm copy and a 45rpm copy - but if I said with these, the 45rpm version sounded better ... you may well retort that it might be a different recording / mastering.  Whereas this one LP is the same version - simply with 2 different play speeds.

 

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