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Nat
 
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Default sampling differences

When you hook a mixer sampling at 24-bit, 192 kHz to one sampling at
16-bit, 48 kHz, what happens? Does everything just get dumbed-down to
16, 48 so your final output is at 16, 48 (assuming input to 24 mixer
to 16 mixer to monitors)? Or does it do something freaky b/c the
different sampling rates trip each other up? Obviously, I don't get
sampling. And I wouldn't be surprised if some of the words I just
used aren't even real.

Any help would be much appreciated.

Thanks,

Nat
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Dick Pierce
 
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(Nat) wrote in message . com...
When you hook a mixer sampling at 24-bit, 192 kHz to one sampling at
16-bit, 48 kHz, what happens? Does everything just get dumbed-down to
16, 48 so your final output is at 16, 48 (assuming input to 24 mixer
to 16 mixer to monitors)? Or does it do something freaky b/c the
different sampling rates trip each other up? Obviously, I don't get
sampling.


What happens is completely at the discretion, or the unfortunate
lack thereof, of the person who designed the equipment.

If you mean if you first put the signal through a 192 kHz/24 bit
mixer, take the DIGITAL output of that and put it into a 48 kHz/
16 bit piece of equipment, first you will find out quickly that
one of two things will happen:

1. The 48 kHz/16 bit mixer cannot accept the signal and will
simply not work at all

2. The 48 kHz mixer can accept the signal, and will downsample
from 192 to 48 kHz and truncate 24 bits to 16 bits with varying
degrees of success, depending upon the quality of the
implementation.

If you're talking about hooking the ANALOG output of one to the
other, then assuming both units are reasonably competently
implemented (a BIG if in the audio world), the result would be
the same as if both units were running at the narrower bit depth
(16 bits) and sample rate (48 kHz).

The difference in sound, practically, given the vast majority of
sources is, at best, going to be extrarodinarily minor and subtle,
a rash of strident and unsupported claims notwithstanding. The
simple fact is that you're not likely at all to find a source of
a musical signal in practicality that exceeds the capability of
48 kHz/16 bit encoding, assuming, again, that it's down properly.
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Dick Pierce
 
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(Nat) wrote in message . com...
When you hook a mixer sampling at 24-bit, 192 kHz to one sampling at
16-bit, 48 kHz, what happens? Does everything just get dumbed-down to
16, 48 so your final output is at 16, 48 (assuming input to 24 mixer
to 16 mixer to monitors)? Or does it do something freaky b/c the
different sampling rates trip each other up? Obviously, I don't get
sampling.


What happens is completely at the discretion, or the unfortunate
lack thereof, of the person who designed the equipment.

If you mean if you first put the signal through a 192 kHz/24 bit
mixer, take the DIGITAL output of that and put it into a 48 kHz/
16 bit piece of equipment, first you will find out quickly that
one of two things will happen:

1. The 48 kHz/16 bit mixer cannot accept the signal and will
simply not work at all

2. The 48 kHz mixer can accept the signal, and will downsample
from 192 to 48 kHz and truncate 24 bits to 16 bits with varying
degrees of success, depending upon the quality of the
implementation.

If you're talking about hooking the ANALOG output of one to the
other, then assuming both units are reasonably competently
implemented (a BIG if in the audio world), the result would be
the same as if both units were running at the narrower bit depth
(16 bits) and sample rate (48 kHz).

The difference in sound, practically, given the vast majority of
sources is, at best, going to be extrarodinarily minor and subtle,
a rash of strident and unsupported claims notwithstanding. The
simple fact is that you're not likely at all to find a source of
a musical signal in practicality that exceeds the capability of
48 kHz/16 bit encoding, assuming, again, that it's down properly.
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Leoaw3
 
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Nat wrote:
When you hook a mixer sampling at 24-bit, 192 kHz to one sampling at
16-bit, 48 kHz, what happens? Does everything just get dumbed-down to
16, 48 so your final output is at 16, 48 (assuming input to 24 mixer
to 16 mixer to monitors)? Or does it do something freaky b/c the
different sampling rates trip each other up? Obviously, I don't get
sampling. And I wouldn't be surprised if some of the words I just
used aren't even real.


The answer is... it depends. What is the exact connection between the two
mixers?
If it is an analog line (the kind you can hook to an amplifier directly and get
sound),
then there should be no problem. One extra conversion to and from digital, but

it should work.

If it is a digital line, then the exact interface makes a big difference. I
believe some interfaces can handle resampling data as it comes in, but a lot
of them have a problem with it.

Your final output will be determined by the last mixer in the chain before the
amplifiers. If that's the
16-bit/48 kHz mixer, then that's what your output will be coming from. If its
the 24-bit/192kHz mixer (and the mixer
is really set to that), then that will be what your output is coming from, but
the 16-bit/48 kHz
signal won't magically become better by going through that. In both cases,
though, the final
signal is converted back to analog anyway, so talking about sampling rate at
the end doesn't make
as much sense.

You'll find the 24-bit board has a lot more dynamics available than the 16-bit
board,
which can be critical. I don't think you'll hear a lot of differences because
of the different sampling
rates, especially live. However, the higher sampling rate board is likely to
have
a better signal chain all the way through, including the analog electronics,
which WILL
have a huge effect on the sound.

If it were me, I'd use the best board as the primary board which is connected
to the monitors and FOH,
and feed it analog signals from the other board.

-lee-
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Leoaw3
 
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Nat wrote:
When you hook a mixer sampling at 24-bit, 192 kHz to one sampling at
16-bit, 48 kHz, what happens? Does everything just get dumbed-down to
16, 48 so your final output is at 16, 48 (assuming input to 24 mixer
to 16 mixer to monitors)? Or does it do something freaky b/c the
different sampling rates trip each other up? Obviously, I don't get
sampling. And I wouldn't be surprised if some of the words I just
used aren't even real.


The answer is... it depends. What is the exact connection between the two
mixers?
If it is an analog line (the kind you can hook to an amplifier directly and get
sound),
then there should be no problem. One extra conversion to and from digital, but

it should work.

If it is a digital line, then the exact interface makes a big difference. I
believe some interfaces can handle resampling data as it comes in, but a lot
of them have a problem with it.

Your final output will be determined by the last mixer in the chain before the
amplifiers. If that's the
16-bit/48 kHz mixer, then that's what your output will be coming from. If its
the 24-bit/192kHz mixer (and the mixer
is really set to that), then that will be what your output is coming from, but
the 16-bit/48 kHz
signal won't magically become better by going through that. In both cases,
though, the final
signal is converted back to analog anyway, so talking about sampling rate at
the end doesn't make
as much sense.

You'll find the 24-bit board has a lot more dynamics available than the 16-bit
board,
which can be critical. I don't think you'll hear a lot of differences because
of the different sampling
rates, especially live. However, the higher sampling rate board is likely to
have
a better signal chain all the way through, including the analog electronics,
which WILL
have a huge effect on the sound.

If it were me, I'd use the best board as the primary board which is connected
to the monitors and FOH,
and feed it analog signals from the other board.

-lee-


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Arny Krueger
 
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"Nat" wrote in message
om

When you hook a mixer sampling at 24-bit, 192 kHz to one sampling at
16-bit, 48 kHz, what happens?


Depends on how you connect them. Most of these devices support both digital
and analog connections.

Does everything just get dumbed-down to
16, 48 so your final output is at 16, 48 (assuming input to 24 mixer
to 16 mixer to monitors)?


Case in point would be one of the Yammy 24/96 mixers running at 24/96
driving an ADAT-format 8 channel analog interface which is running at 24/48.

Yes, the 24/96 is effectively *dumbed down*.

However, the ultimate "dumbing-down" happens at the input to the 24/96
mixer, where it receives input from real microphones in real rooms. It
happens again at the output, where the 24/48 digital signal is sent to a
real loudspeaker in another real room.

While 24 bits is capable of like 144 dB dynamic range, real rooms and by
extension real world recordings are hard pressed to significantly (i.e., 10
dB) exceed 72 dB dynamic range.

For example, a quiet residential room will have a noise floor of about 40
dB SPL. Add 72 dB and now you are at 112 dB, just 3 dB shy of the OSHA legal
limit for SPL exposure of any length.



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Arny Krueger
 
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"Nat" wrote in message
om

When you hook a mixer sampling at 24-bit, 192 kHz to one sampling at
16-bit, 48 kHz, what happens?


Depends on how you connect them. Most of these devices support both digital
and analog connections.

Does everything just get dumbed-down to
16, 48 so your final output is at 16, 48 (assuming input to 24 mixer
to 16 mixer to monitors)?


Case in point would be one of the Yammy 24/96 mixers running at 24/96
driving an ADAT-format 8 channel analog interface which is running at 24/48.

Yes, the 24/96 is effectively *dumbed down*.

However, the ultimate "dumbing-down" happens at the input to the 24/96
mixer, where it receives input from real microphones in real rooms. It
happens again at the output, where the 24/48 digital signal is sent to a
real loudspeaker in another real room.

While 24 bits is capable of like 144 dB dynamic range, real rooms and by
extension real world recordings are hard pressed to significantly (i.e., 10
dB) exceed 72 dB dynamic range.

For example, a quiet residential room will have a noise floor of about 40
dB SPL. Add 72 dB and now you are at 112 dB, just 3 dB shy of the OSHA legal
limit for SPL exposure of any length.



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Scott Dorsey
 
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Nat wrote:
When you hook a mixer sampling at 24-bit, 192 kHz to one sampling at
16-bit, 48 kHz, what happens?


Absolute silence. The clocks don't lock up at all.

Does everything just get dumbed-down to
16, 48 so your final output is at 16, 48 (assuming input to 24 mixer
to 16 mixer to monitors)?


No, but you can either set your first mixer to downsample to a lower rate,
or you can put a sample rate converter between the two in order to convert
to the lower rate.

But rate conversion in general is a bad thing, and it is usually much better
just to run everything off of the same clock as much as possible.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."


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Scott Dorsey
 
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Default

Nat wrote:
When you hook a mixer sampling at 24-bit, 192 kHz to one sampling at
16-bit, 48 kHz, what happens?


Absolute silence. The clocks don't lock up at all.

Does everything just get dumbed-down to
16, 48 so your final output is at 16, 48 (assuming input to 24 mixer
to 16 mixer to monitors)?


No, but you can either set your first mixer to downsample to a lower rate,
or you can put a sample rate converter between the two in order to convert
to the lower rate.

But rate conversion in general is a bad thing, and it is usually much better
just to run everything off of the same clock as much as possible.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."
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Leoaw3
 
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Mike Rivers wrote:
RTFM!


Yeah, but Mike -- not all the manuals are written as well as yours! grin

-lee-
  #13   Report Post  
Leoaw3
 
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Mike Rivers wrote:
RTFM!


Yeah, but Mike -- not all the manuals are written as well as yours! grin

-lee-
  #14   Report Post  
Nat
 
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What I have got is a Behringer Eurorack UB 502. It advertises "130 dB
dynamic range for 24-bit, 192 kHz sampling rate inputs," but there are
no digital ins or outs on the mixer, just analog. But for that
advertisement, I'd assume I could run mics into it and run it into my
16, 48 mixer's analog ins with no problems. I'm just not sure what
that advertisement means. Is it just saying that it's a real good
analog mixer so that if you are using 24, 192 sampling in your
recording, it will let you fully appreciate that sampling rate? If
that's the case, then I don't need to worry about this, no?

And if that's the case, then this was a bad question. Sorry. It
never fails to amaze me how helpful everyone is. I really appreciate
it and feel kinda bad that I don't have any knowledge to give back.

Nat


(Scott Dorsey) wrote in message ...
Nat wrote:
When you hook a mixer sampling at 24-bit, 192 kHz to one sampling at
16-bit, 48 kHz, what happens?


Absolute silence. The clocks don't lock up at all.

Does everything just get dumbed-down to
16, 48 so your final output is at 16, 48 (assuming input to 24 mixer
to 16 mixer to monitors)?


No, but you can either set your first mixer to downsample to a lower rate,
or you can put a sample rate converter between the two in order to convert
to the lower rate.

But rate conversion in general is a bad thing, and it is usually much better
just to run everything off of the same clock as much as possible.
--scott

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