Cubase SX 2 cuts high frequencies?

[SJ_Digriz]

Obviously if you are trying to make a track that is 0db acrossed the board and use 900 compressors and 50 limiters to keep it that way, sure dither is a must.

[Spaceman Sounds]

It's not just a volume difference...because I export sy a synth line made up of 6 tracks etc.. so I can play it back as a wav on 2 tracks...i.e boucing.

I'm playing it back through the same engine Nuendo 2... it does sound different.

if I use a vsti recorder prog on the main buss and record the same take and import that version into nuendo it sounds a bit better... noticably better.

[IIRs]

You need to read closer however hehehe. You can't increase the resolution. You nicely put apparent resolution. Dither works many different ways so I won't make a blanket statement. But increase resolution is NOT one of them.

You are so wrong!

Mithat Konar explains it better than I could:

Here's a simple thought experiment that explains why dither is necessary and how it works. Lets create a basic A/D converter. We'll make it sensitive to DC and bipolar, so it responds to both positive and negative analogue inputs, and we'll give it a very big LSB threshold of 1 volt to make the numbers easy. We'll construct our ADC so that an analogue source over the range between +.5 volts and 1,5 volts produces an output of 1, and so on. If, without applying any dither, we present a 0.25 volt DC (continuous) signal to the input of the ADC, the output of the ADC will be a string of zeros. In fact any signal between -0.5 and 0.5 volts will result in an ADC output of zero. Any information below the LSB threshold is completely lost.

Remove the 0.25 volt signal and apply dither to the input of the ADC in the form of a completely random signal (i.e.,noise) centred around 0 volts. Its peak amplitude randomly toggles the LSB of the ADC. The output of the ADC will be a stream of very small random values. However the average of all these values will be zero.

Now lets apply our 0.25 volt signal again (with the dither on). The two analogue voltages sum together, the dither and our signal. At each sample point (in time), the 0.25 value of our analogue source is added to the random dither value. The output stream wil again look like a stream of very small random numbers, but guess what? The AVERAGE of all those numbers will now be...you guessed it, 0.25. We have thus retained the information that was previously lost (even though its buried in "noise"). In other words, our resolution has improved. The conversion is still essentially random, but the presence of the 0.25 volt signal biases the randomness. Put another way, the characterization of the system with dither on is transformed from completely deterministic to one of statistical probability. The periodic alternation of the LSB between the states of 0 and 1 results in encoding a source value that is smaller than the LSB. In other words, on the average, the LSB puts out a few more ones than zeros because of our +0.25 volt signal. We say that dither exercises or toggles or modulates the LSB.

With the dither on, we can now change the input signal over a continous range and the average of the ADC will track it perfectly. An input signal of 0.371476 volts will have an average ADC output of (the binary equivalent of) 0.371476. The same will hold true of inputs going over the LSB threshold: an input of 3.22278 will have an average ADC output of 3.22278. So not only has the dither enhanced the resolution of the system to many decimal places, but it has also eliminated "stepping" quantisation effects!

[SJ_Digriz]

It's not just a volume difference...because I export sy a synth line made up of 6 tracks etc.. so I can play it back as a wav on 2 tracks...i.e boucing.

I'm playing it back through the same engine Nuendo 2... it does sound different.

if I use a vsti recorder prog on the main buss and record the same take and import that version into nuendo it sounds a bit better... noticably better.

Again, you need to compare apples to apples. When you do a track record like that, you are doing something totally different than what Nuendo is.

Do this. Play back using a wave player and tell me if it sounds the same from the tapeit export in another app against playing in the mixer in Nuendo. I bet the answer is yes. If the answer is no, then the recorder is fiddling with the data stream.

[Spaceman Sounds]

The tapeit recorder file sounds how it does when I playback the track live...the export does not.

I played both files back in nuendo on a seperate track with no processing on them, and I allways chose the tapeit file over the exported one. It's not volume... but something I can't put my finger on???

[SJ_Digriz]

You are so wrong!

Mithat Konar explains it better than I could:

Here's a simple thought experiment..

Great post, although you still need to go further. This is a simplistic explenation. And it actually is saying what I am saying. All it is really doing is replacing truncation noise with averaging noise(in this example). This is more "pleasing" supposedly. But, dithering is done 400 different ways and most of it sucks really bad. The algo that decides the content of the average can be good or really really bad. It can also be really really good and still make really really bad decisions because of the signal content.

Dithering is not a cure all.

[ericj23]

well i just sat and exported a little mix from cubase and reimported into it again

then using the mute and solo buttons on the imported track i was able to switch between the nuendo mix and the mixdown - absolutely no difference

I closed my eyes and clicked randomly between them and i could not even tell if i had muted or solo'ed

but i had

PS you are remembering to export at 32 bit ?

cos if you truncate to 24 bit on export you will of course affect the volume

[IIRs]

All it is really doing is replacing truncation noise with averaging noise(in this example).

No. Read it again! "We have thus retained the information that was previously lost (even though its buried in "noise")"

As I understand it, the differences in "quality" of dither relate to the shaping techniques used to make the noise itself less audible.

[dusted william]

This could very likely be a true problem.

I remember people, including EP, mention that they would only record out of Logic instead of using the rendering. maybe this is the same thing.

dw

[SJ_Digriz]

"We have thus retained the information that was previously lost (even though its buried in "noise")"

Look think about WHY the signal was truncated to begin with. It is PAST the resolution of the export. The only way to retain the source would be to go PAST the resolution again. If you like dithering in this context is akin to digital compression. But that is stretching it a hair. It is guessing and creating a closed shape instead of a squared off shape.

[DwarfNebula]

reading on dither (from one who knows what he's talking bout):

http://www.digido.com/portal/portal/pmo ... file=Blank



btw, www.digido.com is a nice resource on digital audio.

[stefancrs]

It's not just a volume difference...because I export sy a synth line made up of 6 tracks etc.. so I can play it back as a wav on 2 tracks...i.e boucing.

I'm playing it back through the same engine Nuendo 2... it does sound different.

if I use a vsti recorder prog on the main buss and record the same take and import that version into nuendo it sounds a bit better... noticably better.

Try normalising both the bounced and the "recorded" files.

[SJ_Digriz]

reading on dither (from one who knows what he's talking bout):
http://www.digido.com/portal/portal/pmo ... file=Blank
btw, www.digido.com is a nice resource on digital audio.

So Little Noise, So Much Effect
-96 dB seems like so little noise. But strangely, engineers have been able to hear the effect of the dither noise, even at normal listening levels. Dither noise helps us recover ambience, but conversely it also obscures the same ambience we've been trying to recover! Dither noise adds a slight veil to the sound. That's why I say, dither, you can't live with it, and you can't live without it.

Yeah, nothing like hearing it from the experts

[IIRs]

Yeah, nothing like hearing it from the experts

Exactly! Although I can't see his name anywhere on that page, I'm pretty sure the text is lifted from Bob Katz's book..?

Anyway, the important bit is here:

When feeding processors, DAWs or digital mixers to DAT, dither the output of the processor to a 16-bit word. Dithering always sounds better than truncation without dither. But to avoid adding a veil to the sound, avoid cumulative dithering to 16 bit, in other words, multiple generations of 16-bit dither. Make sure that redithering to 16-bit is the one-time, final process in your project.

[C00kie]

This could very likely be a true problem. I remember people, including EP, mention that they would only record out of Logic instead of using the rendering. maybe this is the same thing.

This may be true since a couple of things may be happening:

* Influence of the master volume fader. A recorder VST may be inserted before or after this fader. Maybe rendered output is or is not influenced by this fader.
To rule this out: simply set the master at 0dB.

* Limiting/clipping when going over 0dB. When rendering to 32bits floats the output will not be clipped, but played in the host it will be clipped. Unless the host has an anti-clipping brick-wall limiter builtin ofcourse. That may or may not be applied when rendering.
Simple solution: never ever let peaks go over 0dB.

So either it is a slight difference in volume, or there is a clipping issue. Both can very easily be dealt with, and thus ruled out.

Anybody that perceives a difference in rendered output and output captured by a recorder VST in the master effects slot, should examine in detail where this difference is. This means to have both outputs in maximum resolution, invert phase of one and sum them. If the result of that is total silence, then it is all proven illusional and the problem sits between the ears and not in the host.