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digital values are shape only they have no relation to voltage levels
Old 12th September 2011
  #1
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digital values are shape only they have no relation to voltage levels

Digital samples have the shape of a waveform.
That shape can be transformed into an analog signal.
The d/a sets the voltage levels of the analog.
the digital values only tell the shape of the d/a'ed signal.

the d/a can be made to give as low a voltage as needed to ensure no clipping, NO PEAKS, no problems at all.
a follower amp can raise that recreated signal to be as loud as you want.

if you have any peak problems in the analog domain it is because the d/a was badly designed.

or because you used nonlinear processing on your digital signal in tha tdomain.
Old 12th September 2011
  #2
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Eh, surely if I crank my input signal to a point where the analog devices electronics can't handle it, wouldn't that be user caused clipping?

I'm sorry, but are you asking a question or making a statement?
Old 12th September 2011
  #3
Registered User
Preaching to the Converted (pun intended).

No argument from any reasonable person who understands how digital audio conversion works.
Old 12th September 2011
  #4
Registered User
Quote:
Originally Posted by drumdrum View Post
Eh, surely if I crank my input signal to a point where the analog devices electronics can't handle it, wouldn't that be user caused clipping?

I'm sorry, but are you asking a question or making a statement?
He's talking about DAC, not ADC.

Sure - if you clip your digital audio steam, the DAC is going to accurately reconstruct the clipped signal. That's not really the point.

The problem - I think - is that most people don't understand that digital audio converters are - first and foremost - Analog devices. They are designed to interface with the world of Analog gear. And there are limitations with Analog - it has a sweet spot. Too low, we get too much noise. To hot, we get too much distortion.

So most converters are calibrated for interfacing with Analog gear.

Then we get typical modern producers who can't understand the concept of headroom, and smash their mixes into the top 6dB of their DAW.

Will there be some saturation of transients? - of course. Could a converter be designed with headroom ABOVE 0dBFS to avoid problems?

YES - BUT ... the analog section would then be skewed far away from the idea sweet spot for interfacing with all the other Analog gear out there in the world ...

Just give yourself some headroom, or put up with crunchy sound and just S.T.F.U...
Old 12th September 2011
  #5
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But the 'shape' of a waveform would contain relative amplitude values, no? If so, there would have to be some relation to the eventual voltage level even if not directly dictating it.
Old 12th September 2011
  #6
Registered User
Agreed. Not fair to say "no relationship", when there is a very clear relationship with the voltage of the analog signal.

But the point being hammered home here is that the final overall output level is not dicated by the digital data. It set by the calibration of the analog section of the converter.
Old 12th September 2011
  #7
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Quote:
Originally Posted by oldeanalogueguy View Post
the d/a can be made to give as low a voltage as needed to ensure no clipping, NO PEAKS, no problems at all.
Yes ... but please dude, stop using technical words incorrectly! You and your bloody "peaks"
Old 13th September 2011
  #8
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Quote:
Originally Posted by unitymusic View Post
But the 'shape' of a waveform would contain relative amplitude values, no? If so, there would have to be some relation to the eventual voltage level even if not directly dictating it.
\


relative amplitude is exactly what the shape it
it does not have absolute analog voltage values
that is set by the d/a designer

the only relation is the shape
set by the digital domain

the amplitude values are created in the analog domain (or more accurately the d/a converter)
Old 13th September 2011
  #9
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Quote:
Originally Posted by drumdrum View Post
Eh, surely if I crank my input signal to a point where the analog devices electronics can't handle it, wouldn't that be user caused clipping?

I'm sorry, but are you asking a question or making a statement?
that depends on the desgin of the a/d converter

i can guarantee that you cant clip that either
but economics makes most corps design it so that you have to do that for yourself

i made a statement
antoher thread has people really confused about a/d/a and where the problmes come from
Old 13th September 2011
  #10
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Quote:
Originally Posted by timlloyd View Post
Yes ... but please dude, stop using technical words incorrectly! You and your bloody "peaks"
i am using words correctly

something tht is higher than a reference value has peaked

you are using them in a confusing way claiming that an exact analog value has some how peaked when it is exactly the same as it shoudl be

stop confusing the digital and analog domains
there are no voltage values in the digital domain
so no analog value can peak over any sample
and certainly not between them
Old 13th September 2011
  #11
Registered User
Do you agree with my point about that converters are primarily analog devices, designed to interface with analog gear?

Analog electronics have a pretty limited dynamic range and signal to noise (compared to digital), hence the need to find the best compromise between the two worlds.

There are some cheap converters with poor headroom, and they can sound very colored even before digital zero. Have you ever run tests with sinewaves into converters? It's interesting - you can see that the sine wave is a sine wave on the screen, but as you raise the level up to 0dBFS, you can hear the D/A introducing more and more harmonics ...

Most converters are designed around analog gear that has 0dBVU at around -18dBFS.

The problem is that we are running digital too hot, because it APPEARS as though we can - but in reality we are pushing our converters far away from their designed sweet spot.

(Assuming everyone cranks their digital output up to max ... in the real world, I don't think this is hardly an issue because how many people with real world devices actually slam their D/A with an unattenuated digital stream?)

If it sounds good, it's good. If it sounds bad, it's bad. Regardless of the numbers.
Old 13th September 2011
  #12
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Quote:
Originally Posted by Kiwi View Post
Do you agree with my point about that converters are primarily analog devices, designed to interface with analog gear?

no
they are hybrid digital/analog devices
else they could not do conversions

they are designed to interfact to both analog and digital gear at the same time else why would they exist at all

Analog electronics have a pretty limited dynamic range and signal to noise (compared to digital), hence the need to find the best compromise between the two worlds.

analog has plenty of DR and SNR
digital may or may not be better
but yes you have to compromise all the gear to get the best overall end result


There are some cheap converters with poor headroom, and they can sound very colored even before digital zero. Have you ever run tests with sinewaves into converters? It's interesting - you can see that the sine wave is a sine wave on the screen, but as you raise the level up to 0dBFS, you can hear the D/A introducing more and more harmonics ...

nyquist and fourier in action
which seems to surprise those who love pushing the envelope in the digital domain

Most converters are designed around analog gear that has 0dBVU at around -18dBFS.

some are. but that is a good setting.
i would prefer -24 but I am very conservative.

The problem is that we are running digital too hot, because it APPEARS as though we can - but in reality we are pushing our converters far away from their designed sweet spot.

not doing squat to teh converters. doing what you noted is messing up the digital signal so the converters do what they should do which is convert your distorted glob of infinite bandwidth including foldbacks that it caused in the digital side.

(Assuming everyone cranks their digital output up to max ... in the real world, I don't think this is hardly an issue because how many people with real world devices actually slam their D/A with an unattenuated digital stream?)

from the posts here most everybody does
and from otehr forums too. everybody wants max loudness and slam everything over 0dBFS while compressing limiting and pushing rms up to -3 or worse.

If it sounds good, it's good. If it sounds bad, it's bad. Regardless of the numbers.

see comments inserted in bold
Old 13th September 2011
  #13
Thread reported - please leave this nonsense out!
Old 13th September 2011
  #14
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Quote:
Originally Posted by psycho_monkey View Post
Thread reported - please leave this nonsense out!

what nonsense?

you dont have to read it if you dont like the discussion

if multiquote worked on my pc i would use it
but GS has buggy code. many things dont work right on xppro and firefox.

if you post a long list of stuff
i will insert my answers to make it easier to do
Old 15th September 2011
  #15
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Quote:
Originally Posted by timlloyd View Post
Yes ... but please dude, stop using technical words incorrectly! You and your bloody "peaks"
you speak british english
i speak correct english
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