New Hdcd Default-question

[Priaptor]

With upgrading to 14.1 there is now a default checked that says :

"+6 dB Amplification (align 20 bit result in upper 24 bit range"

I re-ripped Hadouk Trio Live at Flip, which is an HDCD encoded disc and compared it to the prior ripped version with 14.0 and the new one sounded unnatural and overextended and the bass was way off.

Can anyone explain what this new default is. It sounds simple as though they are adding 6 db of gain for HDCD, then they go onto to say, "align 20 bit result in upper 24 bit range", which makes me think that the HDCD encoding will not be applied unless this default is checked.

Any help is appreciated.

[Spoon]

Re: New Hdcd Default-question

HDCD is applied regardless of the check. The amplification is quite simple, have a look at the waveform in Audacity to see if it clips.

[Priaptor]

Re: New Hdcd Default-question

I guess I don't understand why the have that as a default or why they have it at all? Does the HDCD encoding process entail reducing gain while cutting the disc so that a 6db gain amplification somehow is necessary to compensate?

Given that it is a new inclusion on 14.1, I wonder the reasoning.

[Spoon]

Re: New Hdcd Default-question

HDCD does not entail the reduction of gain, only when going from 16 bit to 20 bit the decoding is not in the upper 4 bits, so if you play against 16 bit where it is in the upper bits it will sound half as loud.

[Priaptor]

Re: New Hdcd Default-question

Appreciate the help. I did indeed use Audacity and there is a huge amount of clipping in the Hadouk Trio disc ripped with the 6db gain. My ears were not deceiving me.

I am learning and Audacity is a great tool. Thanks

[Lynx_TWO]

Re: New Hdcd Default-question

Appreciate the help. I did indeed use Audacity and there is a huge amount of clipping in the Hadouk Trio disc ripped with the 6db gain. My ears were not deceiving me.

I am learning and Audacity is a great tool. Thanks

I know this thread is a bit old, I just wanted to say I just ripped The Faint - Danse Macabre using the +6dB setting, and it also clipped a lot. Other discs did not, so this should probably be addressed...

[S. Cartographer]

Re: New Hdcd Default-question

HDCD does not entail the reduction of gain, only when going from 16 bit to 20 bit the decoding is not in the upper 4 bits, so if you play against 16 bit where it is in the upper bits it will sound half as loud.

So, what happens if I uncheck the +6db option? Will the volume of all the tracks be lower? If so, can't I just adjust the volume higher during playback?

Specifically, I'm trying to rip my one and only (known) hdcd - Lateralus by Tool. I'd like to get the best possible sound quality. If I can verify that I can get the HDCD quality by using dbpoweramp ripping into a flac file and experience the increased quality with playback through any source, you've made a sale! (My primary computer is a Mac so I can't just play the cd through WMP in day to day scenarios.)

I've read conflicting opinions on how to rip HDCD. It seems to me like ripping to a 24 bit flac (or any other lossless format) file with the HDCD audio restoration applied during encoding instead of at playback time is the ideal way to do it, if that's possible. Wouldn't that make the playback identical to playback form a HDCD enabled player but on any device capable of playing flac?

I hope my rambling is making some sort of sense!

Thanks!

[Lynx_TWO]

Re: New Hdcd Default-question

Absolutely I am tracking perfectly

Uncheck the +6dB setting. I own the Tool CD, and under amplitude statistics analysis in Adobe Audition it states the measured bit depth is 20 bits, peak amplitude is -6.12 dB, true peak amplitude is -5.63 dB. This is after HDCD decoding. I suspect whoever decided to make the +6dB amplify option for HDCD decoding forgot about the range extension option in the HDCD specifications, which probably was not used on the tool CD, but WAS used on The Faint "Danse Macabre" CD. On the Tool CD, specifically, HDCD was not utilized as well as it could have been. For example, some tracks only have a measured bit depth of 17dB after decoding. However, seeing as every 1dB of resolution can result in 6dB of musical dynamic range, 17dB has a theoretical dynamic range of 102dB vs 16-bits 96dB.

Another example is the Disney "Tarzan" CD. When the +6dB option is checked, there is some slight clipping, and Adobe Audition measures the bit depth at 16 bits. When the +6dB option is NOT checked, there are higher peaks with no clipping (this indicates more dynamic range) and the measured bit depth is 20 bits per sample.

IMHO +6dB should NEVER be checked when decoding HDCDs to 24-bit FLAC files. HDCD decoding is a non-reversible process, so it is better to leave the amplification setting off.

Your files will be 6dB quieter, that is true, but with replay-gain enabled during playback on any software, this overcomes any issues. I would highly recommend adding the replay-gain (scanning only, not applying) DSP after the HDCD decode DSP. This will re-scan the replay-gain value for equal-volume playback on all devices.

Just a quick rant here, but replay-gain or something like it is used by most DJ's and is built in to most DJ software. Artists should NOT master their music so loud, or "hot" because all the software will do is turn down the volume on playback anyway. Better to keep all the pumping dynamic range instead!

[Porcus]

Re: New Hdcd Default-question

I am repeating myself here, but when ripping to lossless I would not apply HDCD decoding at all. Personally I decode on-the-fly upon playback, but even if I weren't to do so, I would have wanted to test an entire album for HDCD content before any decoding.

There are a lot of HDCDs with no HDCD features too. That is, they simply have a flag saying 'I am a HDCD and upon decoding you should do as follows:'
(notice there is nothing after the colon sign).

[Goes To 11]

Re: New Hdcd Default-question

I am repeating myself here, but when ripping to lossless I would not apply HDCD decoding at all. Personally I decode on-the-fly upon playback, but even if I weren't to do so, I would have wanted to test an entire album for HDCD content before any decoding.

There are a lot of HDCDs with no HDCD features too. That is, they simply have a flag saying 'I am a HDCD and upon decoding you should do as follows:'
(notice there is nothing after the colon sign).

So, what would HDCD decoding, applied during ripping, do to a CD flagged as HDCD but which has no HDCD features?

[Porcus]

Re: New Hdcd Default-question

So, what would HDCD decoding, applied during ripping, do to a CD flagged as HDCD but which has no HDCD features?

I have only ripped to FLAC, in which case it is stored it in a 24-bit file (I think that is the default configuration) in order to make (head)room for the peak extensions and low-level extensions that are not there. The track will sound the same with or without HDCD decoding, at least after aligning volume. But precisely that appears to be an issue:

I have CDs where some but not all tracks are HDCD tracks, and were converted to 24 bits because I back then made the mistake of applying HDCD upon ripping. Now ReplayGain compensates for the 6 dB, but only track by track; all tracks have the same album gain, while they should differ by 6 dB. (I cannot anymore check which features were used, and if decoding were even theoretically good for anything.)