If you could repeat QAI with 'my' 16/44.1, you could see if these bumps are there also. If so, it's likely to be AI doing this, no?

EDIT: No, of course you can't - they're not aligned, and you're not going to do that, right?

Mani.

QAI applied to my native 16/44.1 came 2nd in my 'Objective Assessment', after the native 24/176.4. I'm going to give QAP and QAI applied to Josef's 16/44.1 file a good listen... might be interesting.

Mani.

Well, work has been very quiet over the summer, but will kick off in earnest in about 2 weeks time. I've just been trying to get as much done as possible around the house and on the hifi before I start living on a plane and in hotels again. My dream is to come back home after a work trip, spend time with my family and then relax in front of the hifi, just listening to music... without obsessing over how it sounds!

One thing I've been thinking about though. Your recordings - you're using the FF800, right? This uses delta-sigma ADC chips. Now, I have no idea how these things work on the ADC side, but they must be OK. I mean, they can't be mangling up the sound, because you're getting such good results from your live recordings. So, would there be any advantage in using a multi-bit ADC chip, like the one in the PM2?

Mani.

BUT... I prefer the sound of my 16/44.1...

EDIT: Pacific Microsonics strongly recommends using the 1:4 Interpolation in the PM2 for 16/44.1, but I don't like the way that sounds either.

Peter, as Josef's 16/44.1 has been derived directly from the original 24/176.4, would it be possible to create another graph comparing QAP applied to his 16/44.1 vs. the original 24/176.4? This would give us an excellent idea of how accurately AP can reconstruct a hires file.

Mani.

WOW! Great analysis Peter. Thanks.


I agree with this 100%. What I call the native-16/44.1 sounds the most different from the vinyl. And the native-24/176.4 sounds the most similar to the vinyl (actually identical, as far as I can tell on my system). Josef's 16/44.1 definitely sounds more similar to the vinyl than my 16/44.1.

Mani.

Haha... this is what they meant by 'dynamic decimation'

Looking forward to your next post before I respond...

Mani.

Firstly, let me ask a favour of you - please take what comes below in the spirit in which it’s meant. I’m not here to convince you of anything. I’m just here to share my experiences that you may or may not find useful or interesting.

18 months ago, I bought a couple of ‘HRx’ 24/176.4 WAV albums (burned on DVD-Rs) from Reference Recordings and was really taken aback by their SQ. There was a ‘quality’ that they possessed that I hadn’t heard before from any of my ripped or downloaded 16/44.1 files. This quality is hard to put into words. Extra low-level information? Smoother? More dynamic? I’m not sure that any of these manage to describe the particular quality that I heard. The only really accurate description that I can offer is ‘life’ – the music ebbs and flows as if it’s alive. (But please don’t mistake this description for ‘life-like’ – you would never mistake these files being played back on my system for the real thing. A better analogy would be with a painting – great paintings have so much ‘life’ in them, but they’re not necessarily ‘life-like’ at all. Do you understand what I mean?)

And this got me thinking about 16/44.1 vs. 24/176.4. Are the former inherently inferior to the latter in an audible way? If so, is there anything that can be done about this?

I wanted to be as objective as possible. Of course, it’s impossible to be totally objective, but I wanted to eliminate as many of my own biases as possible. The best way seemed to be to get an analogue source, record it at the two different resolutions and compare the recordings with the original analogue source. An assumption that I’m making here is the absolute quality of the playback system (preamp, amp, speakers, cables, etc) becomes irrelevant because it is the same system used in all cases. Of course, this is only valid if the system is resolving enough to allow any differences to heard – and I believe it is.

Method

Before making the comparison between the vinyl, native-24/176.4 and native-16/44.1 files, I wanted to ensure that my digital chain was totally transparent.
I tested the following two routes:
1. phono stage -> AD -> DA (i.e. internal)
2. phono stage -> AD -> AES cable -> RME PCI card -> RME mixer -> AES cable -> DA
Irrespective of sample rate, I found that there is absolutely NO difference in sound between these two routes. (Incidentally for 2, I knew that I really was passing through the RME mixer because I could hear any changes I made to levels, muting, etc in the RME mixer.) From this, I concluded that the AES cables, the RME PCI card, the RME mixer and the RME driver are all transparent enough for the purposes of this assessment.

Objective Assessment

(Yes once again, I know that this cannot be truly objective if I am making the assessment...) I played the vinyl and was looking for the digital file that sounded closest to it. IN COMPARISON TO THE VINYL, here is my ranking:
1) native-24/176.4
- sounds identical
- cannot distinguish in double blind listening tests
2) (XX) QAI of native-16/44.1 = (PM) 1:4 Interpolation of native-16/44.1 = (Software) 4:1 Decimation of native-24/176.4
- tonal balance maintained
- less depth
- rounded transients
- less low-level detail
3) (XX) QAP of native-16/44.1
- sharper
- leading edges (over?) emphasised
- cymbals sound thicker and much less delicate – the initial strike is more emphasised but the shimmer/decay is attenuated
- less body and weight to instruments – they sound smaller and ‘cheaper’
4) native-16/44.1
- brighter
- more edgy
- more forward

I suspect that most people would come to a similar conclusion here. I’ve played the vinyl to a number of (non-audiophile) people and then these digital files. Asking them which digital file sounds most similar to the vinyl, I get very similar results to above, although they often find it difficult to articulate exactly why they think what they do.

Subjective Assessment

Here, I consider which digital ‘sound’ I most like and can most happily live with. My ranking is:
1) native-24/176.4
- I don’t long for anything else, this has it all
- it is detailed and yet totally smooth and easy on the ear too
- it has the all-important ‘life’ quality
2) native-16/44.1
- this has ‘life’
- it breathes
- although it is brighter and more edgy than the native-24/176.4, I can live with this
- it doesn’t annoy (too much)
- good boogie factor
3) (XX) QAP of native-16/44.1
- the ‘life’ of the native-16/44.1 is maintained
- sounds very impressive on first playing
- tight as hell
- all instruments/voices are absolutely delineated and focused
- phenomenal boogie factor
- but gets fatiguing after a while
4) (XX) QAI of native-16/44.1 = (PM) 1:4 Interpolation of native-16/44.1 = (Software) 4:1 Decimation of native-24/176.4
- very smooth and easy to listen to
- all the ‘life’ has been sucked out of the music
- great for innocuous background music

Conclusion

No, I couldn’t get 16/44.1 to sound as good as the vinyl source or 24/176.4. But I can get it to sound ‘good enough’ to listen to, and more importantly, to ENJOY. Playing the native-16/44.1 file hits this spot. Using QAP with my setup doesn’t. But I’m holding out for OAP on a NOS1... which I'm hoping will do it.

Cheers.
Mani.

I currently use Option 1: Music\Genre\Artist\Album - to me, this just seems the most logical way to do this.

Any variations come under the 'Artist' folder. E.g. All albums by 'The Keith Jarrett Trio' come under the folder 'Keith Jarrett' - and I tend not to create a separate sub-folder for these, but then again, I don't have 200 albums by one artist!

Mani.

I wrote this in another thread a while ago:


Mani

Josef, the comparison wasn't meant to be just between the native 16/44.1 and the native 24/176.4. I was hoping that people would try comparing an AP-upsampled 16/44.1 to the native 24/176.4. I know of one person on this forum who actually prefers the former to the latter.

As for downsampling/decimating the 24/176.4 to 16/44.1 and comparing it to the native 16/44.1, well this is exactly what my ADC does internally when recording at 16/44.1 - internally it works at 24/176.4 (or 24/192) and downsamples/decimates to 16/44.1. So here you will really be testing whether your decimation DSP is better than the decimation DSP in my ADC. Still, an interesting test (for me at least) which I will do.

Which program did you use for the downsampling/decimation?

Cheers,
Mani.

Thanks Marcin, thanks pedal for your views.

I'm still looking for others' experiences before I share my own...

Cheers,
Mani.

For those of you who downloaded these files, I'd really love to hear your thoughts on the sound of the 16/44.1 vs. 24/176.4 file.

Cheers,
Mani.

I use a hiFace in my office system and have never heard any ticks at all. And this is with a very modest Atom-based PC usiing Adaptive with 1024 buffer.

In my main sytem, I have an RME PCI interface and when I switch HDCD decoding on, I get an intermittent loud tick from the left channel.

Sorry if this doesn't help.

Mani.

Done. You can download them here: http://www.filemail.com/dl.aspx?id=ZPOOCCHMGRMLXGT

But, I wouldn't get too excited - I used a pretty modest vinyl setup:

- Technics SP-10 MkII turntable on a solid metal plinth (wall-mounted on a solid brick wall)
- SME 3009 S2 (pre-improved) arm
- Denon 103 cartridge
- Cardas armtube cable (single run from cartridge to phono stage in balanced configuration, terminated with XLR plugs)
- AQVOX phono stage (balanced MC input, balanced output)

(For those of you who are interested, the cartridge resonance occurs below 10Hz with this setup.)

On the digital side:

- Pacific Microsonics Model Two
- AES/EBU cable (for signal) and BNC-terminated coaxial cable (for wordclock)
- RME AES-32 PCI interface
- RME Digicheck 'Global Record' software

(No analogue or digital gain/attenuation was used whatsoever in the AQVOX, the PMII or the RME.)

Cheers,
Mani

Oh, I see what you mean. For playing back 16/44.1 files, why in the 'DAC Settings' section don't I just choose 'DAC is 16 bits and 44.1KHz', right? Well, this means I can't use AP/PeakExtend or use the XX vol. control (in a lossless way) or play back hires files. Of course, if you don't use these anyway, then I guess you're OK.

Mani.