Converting Flac to Wav & Upconversion

Mezmo wrote:
"Steve, have you found that permanently up-sampling files with a purpose-built program (ie, Izotope) is beneficial?"

Depends on your DAC. With most DACs, this type of upsampling from 44.1 to 96 can be very beneficial. More detail and improved dynamics. Smoother vocals.

The problem I have found with FLAC is that on many systems it compresses the sound a bit. I believe that it is not changing the data when run statically, but dynamically something is happening to corrupt the data. With cheap disk prices and AIFF format, there is really no reason to play FLAC files. Convert them to AIFF or .wav.

Steve N.
Empirical Audio

"With most DACs, this type of upsampling from 44.1 to 96 can be very beneficial."

YEs, it can, but it all depends on what specifically is done during the upsampling and that is done correctly and that the playback system is sufficiently resolving and dynamic.

The upsampling process is essentially an opportunity for the designer to digitally remaster the raw data as desired. There could be more to it that strictly just up-sampling alone. There are many common enhancement algorithms that might be applied.

As usual, the devil is in the details in each case.

Uncompressed upsampled files will be much larger. BEsides disk storage, network or computer bus bandwidth limits are more likely to come into play. IT is not without some potential risk/downside as well.

So if you do it, make sure what you hear is worth it. Bigger is not necessarily always better when it comes to digital files.

Unlike analog audio, which records a smooth and continuous waveform in real time, digital audio must capture audio samples in a series of discrete steps numerous times per second. The more often you can sample, the smoother and more faithful the recording will be to the original analog sound. (Remember, sounds in the real world that our ears hear are analog.) A standard music CD has a sampling rate of 44.1 kHz, whereas high-res audio can go up to 96k or 192k. (Most tests have concluded that 192k is overkill without much practical benefit.) Aside from the occasional concert movie, almost all feature films and television shows are mixed at a rate of 48 kHz. This is unlikely to change in the foreseeable future due to a variety of logistical issues in the film production pipeline. For example, 96k files require twice as many mixing resources as 48k, which means that only half the number of channels on the console would be available. Not to mention that the average movie soundtrack is comprised of numerous audio elements recorded at a variety of quality levels. 48k is a common standard that works and doesn’t seem ready to change.

I have Musica Pristina Virtuoso music server and here is my experience.

1 When I rip CD into WAV and FLAC (two separate files) and compare both - WAVE is dramatically better then FLAC which sounds lean, thin, 2D and castrated

2 When I take FLAC file I have downloaded from HDTracks.com or hidefenitiontapetransfer and convert it to WAV format I never experience sound degradation described in TAS recently. Converted WAV is better then FLAC but not in 100%. So I do convert as there is no downside (besides space which is cheap now) and potential improvments. Sound characteristics as I described above

3 When I upsample file, WAV or FLAC, (I use Musica Pristina software) then I hear tremendous improvment in highs: silkier, extended, air, instrument separation. Bass does not change (a bit tighter) but is not so promiment in comparison. Its natural, as we just improved highs and ear is not used to it! Later on, bass sound "normal"

I believe that upsampling results depends grealy on the DAC you use because if it does its own upsampling then done twice it could be worsen, in theory I believe. My DAC is Esoteric K-01 USB DAC portion of this SACD Player.

Done right - the SQ is better then majority of analog gears I auditioned in my life

Dob - It helps to understand why upsampling makes things sound smoother and silkier. Its not due to the upsampling itself, it because a different digital filtering is being auto-selected in your DAC. This higher frequency roll-off filter has less impact on the SQ.

If you can manually select the digital filter, then the advantage of upsampling the file goes away. You can select a high-frequency filter for all files for instance. That is what I do. This is even better than upsampling because you have the best of both worlds: the data is not modified and the digital filter is not impacting SQ.

Steve N.
Empirical Audio