INTERACT FORUM
More => Old Versions => Media Center 12 (Development Ended) => Topic started by: JONCAT on August 26, 2008, 11:26:25 am
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If we attenuate with JRiver's volume control (32bit internal volume control) aren't we losing 1bit per every 6db. I fail to see what is really lost given the amount the bits we start with on most recordings. Frequency reproduction isn't changing, and amplitude isn't changing relatively between freqs.
So why is bit-perfect touted as superior. I doubt that anyone would notice a 10db digital attenuation applied via something like EMU Patchmix of JRiver volume control.
I understand certain things like Surround sound must be bit-perfect to be passed via S/PDIF but.....what's the big deal about bit-perfect. Aren't volume controls 32bit for a reason?
DC
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Bit-perfect means that Media Center doesn't monkey with the signal, unless you tell it to. That's good.
32-bit is a different issue, but also good because it provides more headroom for DSPs like volume without a loss of precision.
To put the 32-bit question in a simple way, what is better:
3 / 2 = 1 (16-bit integer)
3 / 2 = 1.5 (32-bit float)
The integer approach loses precision. The 32-bit approach does not, so is a lossless transform.
As you divide by bigger numbers (more volume attenuation), this rounding becomes more relevant.
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Thanks Matt.
When is MC bit perfect and when is it not?
With Replay Gain disabled and all other DSP options off?
What if the volume slider (internal) is lowered below 100%?
DC
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When is MC bit perfect and when is it not?
With Replay Gain disabled and all other DSP options off?
What if the volume slider (internal) is lowered below 100%?
Any processing, including internal volume, changes the signal. The output is no longer bit-perfect with the original CD (or other source) at that point.
The important question then becomes with what quality are changes being applied. Using a 32-bit chain is important here, because even if you're still scaing down to 16-bits in the end, you only pay the rounding penalty once instead of at each filter stage. It of course also allows you to output at 32-bit so no rounding occurs.
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Right, and I fail to see why say, a 10db digital attenuation, while creating a non-bit-perfect output would ever be audible when 32bit processing is used.
My point is, people argue that the music is "changed", "not the way the artist meant it to be heard". These are VERY overblown claims imo. Frequencies are not changing as bits are tossed away, and nor is their relative amplitude.
If I record a vinyl track at 24bits and apply digital RIAA, a rumble filter, and some noise removal......no doubt I have lost some bits in the process. I can only imgaine how little affect something like even a -20db attenuation with a 32bit internal volume control would have on a 16bit file.
DC
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My point is, people argue that the music is "changed", "not the way the artist meant it to be heard". These are VERY overblown claims imo. Frequencies are not changing as bits are tossed away, and nor is their relative amplitude.
I guess I didn't see the original claims.
If someone is saying that adjusting the volume (digitally or in analog) is changing "the way the artist meant it to be heard", I'd try to sell them a bridge.