bigshot
Headphoneus Supremus
I'd like to comment on the charts posted at the beginning of this thread, but I'd like to get an answer on their context. ADD would you please see post 27?
Thanks
Steve
Thanks
Steve
Originally Posted by bigshot /img/forum/go_quote.gif I'd like to comment on the charts posted at the beginning of this thread, but I'd like to get an answer on their context. ADD would you please see post 27? Thanks Steve |
Originally Posted by Simon Sez /img/forum/go_quote.gif If I took a record (vinyl) and recorded it @ 24bit 48khz in pro tools would it sound better than the CD of the same name. I realize that higher conversion = better sound, but I'm not really giving it a better sample rate am I? Also if it did sound better, how much better would it sound? |
Originally Posted by slwiser /img/forum/go_quote.gif To me the chart makes no sense but as you said the context is all important. My interpretation would be that it has to be a slice in the time domain, maybe 10 ms or so reflection |
Originally Posted by james__bean /img/forum/go_quote.gif I make my own vinyl rips all the time. People always talk about how you can't hear above 20kHz, but I've directly compared a rip done in 24/48 to the same rip converted to 16/44 with foobar2000's ABX test. I picked out the difference like 95% of the time, which leaves the probability that I can't hear the difference like .01%. Its easy when you listen to the symbols. |
Hi all,
Fascinating to see what people really think about hi-res digital V CD. So many facts and even more fiction
Sorry, it’s a big, long post and I hope you’ll stick with me. Maybe save it for later. I speak from experience 'cos this is my living so I hope you'll agree with at least some of it!
CD resolution Vs. 96/24?
There is no comparison. 96/24 is better – indeed I couldn’t do my work to the high standard my clients demand without it - and there is no sonic reason why it isn’t better for the amateur or hobbyist. There are plenty of cost and efficiency factors so that probably explains why people are still willing to defend CD resolution as if it were something worthy of defending in its own right, yet they still won't recognize the clear benefits that 96/24 delivers. It’s all too easy to dismiss 96/24 on the grounds that ‘you can’t hear a difference’ and that annoys the h*ll out of me. I’m here to tell you that you can hear a difference. We ALL can. Even if you’re deaf I hope to prove this:
Of course 96/24 uses more resources and processing time but in the world of real, living sound you don’t get anything for free and limitations come at a huge cost to accuracy. Strictly speaking, it is impossible to ‘capture’ sound - this cannot be overstated. There will always be some link in the recording/reproducing chain that gives the game away. Any increase in sampling rate cannot in itself be a bad thing!
Put simply: 44.1/16 is NOT enough for the job I do. My job is to take audio from vinyl sources and create a remaster for CD re-issue (or in some cases back to vinyl). If I was asked to work at 44.1/16 as a base sample/bit rate, I would be at a disadvantage. I would be losing a wealth of valuable information that I would never be able to find afterwards. Ever. For those of you who noted that fixing defects and unwanted sonic artefacts is easier in 96/24, I know this to be true from experience. It doesn’t mean ‘easier’ in terms of resources, it means ‘possible’ purely in sonic terms.
Not strictly related but I’ll give you an example of how more info is better: I often receive vinyl material that is originally recorded in mono. However I always make a stereo recording of the mono vinyl for restoration purposes. If you fold a stereo recording of a mono source down to mono, it will produce less noise however it will hinder restoration work because you no longer have the option of taking final samples from the ‘good’ channel, say, if a click is only on the left. Stretch this analogy to almost any region of sound and you soon realize that more information is always going to be more useful to an audio restoration project. Strictly speaking the only limiting factors are cost and speed.
This area of audio ‘salvage’ is becoming increasingly more important because original source material is fast disappearing. Master tapes do not last forever and even if well kept they will degrade through unavoidable processes such as chemical breakdown of polymers and tape strata, demagnetization and cosmic ray bombardment. A large number of well known recordings have already gone forever - it's just not public knowledge yet. Nobody really knows how this is going to affect the re-issue side of the industry because it's still not clear whether anyone cares... but I do! What is perfectly clear to me, if not to the music industry is that the sound quality locked up in those vinyl grooves is more than good enough for a CD re-issue or even better. And vinyl doesn’t degrade in sound quality like tape does. Look after it properly and it’ll be as good as new in hundreds of years time. Not so with tape. Digital? Stays the same forever of course but if it’s not good enough to begin with...
OK so I do this for a living – what of the hobbyist? Here sadly we must leave a lot of vinyl replay behind us because you do need a very good vinyl set-up to make a difference. We’re talking moving coil, Linn, Rega, low oxygen-copper leads, outboard A/D, yada yada, etc.
Sorry.
A note on CD: It’s important to remember that 44.1/16 (hereafter ‘CD’) was chosen because it satisfied the requirements of the audio industry at the time (early 1980's) and represented the agreed maximum bandwidth for the then new CD format, after arguments over size of the disk, maximum recording time, sound quality etc. The decision was taken with great care and no little discussion. It’s also very important to remember that CD was introduced more than quarter of a century ago. Things have moved on.
CD sound quality over analogue:
So many arguments... my bugbear is this: the argument still persists that because the average listener cannot hear up to, never mind OVER 22.05 KHZ (the sample rate per channel of CD) then it follows that overhead is built into the CD system. This thinking was valid at the time but is now known to be flawed. The assumption was that the only thing required was to reproduce all hearable frequencies at a basically accurate volume over a reasonably accurate time. Unfortunately it's that simplicity that got them caught out.
We now know that there are three fundamental values to any sound format; 1) frequency, 2) quantization (volume), 3) location (add echoes as you like ;p).
Location is the hard one, and it hardly ever gets mentioned because it has no strict measurable ‘rate’ but is itself a factor of the combination of the sample rate (frequency mostly) AND the quantization amount plus other factors such as reproducer (speaker). For the purposes of this argument I shall call it ‘timing’.
For frequency response 22.05 khz is enough for humans. However for timing and quantization (volume), 22.05 at 16 bit is not and it is audibly not. The problem is that you hardly ever get a chance to make a comparison. Go home and listen to a CD, then go to a hi-fi shop and listen to the same music on a SACD or DVD-A and you’ve already lost too much time in memory. Do it side-by-side and it’s a lot easier but still flawed – the equipment usually doesn’t sound the same, never mind the mastering.
OK so think about it purely mentally: Try and imagine two trains running on parallel tracks, both running at the same speed but one infinitesimally ahead of the other. What does that sound like? Optically it would be ‘a photo finish’. Sonically? The smaller the difference between the two trains location, the more numbers you need to throw at the measurement to make a measurement at all. In other words, more resolution. The human ear/brain combination is an astonishingly capable tool for detecting sound but perhaps not in the way that you think: bats can hear higher frequencies but they are only doing better, what we can ALSO do, and that is: locate sounds 'in space' and ‘in time’. For a bat it's a question of survival. Darwinism has seen to it that a bat can detect incredibly high frequencies but what is usually lost in the description is that bats further process those frequencies against an environment of time and space - and this we humans can also do (although not as well!)
Another way of saying this is: two sound events (from a stereo for example) can be very slightly ahead or behind each other and we can tell the difference with great accuracy, time after time. Think of a drum kit. You’ve never heard a drum kit recorded so it really, but really sounds like it’s in front of you, have you? (You’re very lucky if you have) but you know when it’s ‘live’ because it’s those very small timing differences that we can distinguish (plus all the surround info from real life). It’s those timing differences that CD cannot reproduce, and, given a good enough system, a vinyl LP can go some way towards reproducing. Fact: Analogue doesn’t have that timing problem. Digital always will. The only way to battle it is to throw more numbers into the digital mix.
Here’s a real life example: I shall use Bob Marley Live at the Lyceum for example for three important reasons: 1) I just worked on it, 2) it’s a live recording that didn’t suffer too much at the hands of studio engineers, 3) it has a top frequency response of around 17Khz, well below CD’s capabilites.
I’ve had the CD issue for years but listened to it maybe once - it sounds like a cardboard cut-out of the recording I was used to on vinyl, no atmosphere. The 96/24 DVD-A I just made, taken from vinyl (itself mastered from the original analogue tapes), walks all over the CD and takes names. Island had the master tapes as a source for their CD, I had a vinyl LP. Therefore and with no real argument, LP is clearly capable of producing something nicer sounding, not on a basis of frequency response but on something else. Something I now know to be accuracy in timing and quantization. Timing.
OK so it’s possible to argue that none of this matters – the average listener makes their choices on matters less lofty than such esoteric sound quality arguments. Good vinyl replay costs a lot. But for professionals it remains a constant factor in our choices because we know it works better at 96/24 and above. Fact. No argument.
All I can say in summation is that there IS a difference and it’s there to be heard. You CAN hear it.
Colin AKA See Why Audio
There's no advantage to capturing in 24/96 if the source is an LP. The only thing that will benefit from the added resolution is the bed of surface noise down at a low level where you can't hear it anyway. Capturing this high makes applying filters slow and increases the opportunity for hard drive underruns.
Capture to 16/44.1 and burn to redbook, and it will sound exactly the same.
See ya
Steve