Sorry, Karl, as said earlier, at the moment I'm using a laptop with pretty terrible sound - I wouldn't trust anything that's coming through - so, don't hold up anything on my account.
About all I might say is that the treble quality seems to be less in the later section - but, I wouldn't put money on it !
So, spill away!!
About all I might say is that the treble quality seems to be less in the later section - but, I wouldn't put money on it !
So, spill away!!
The video compression algorithm works quite a bit differently than with music. In video the sender must keep his data rate low enough to fit through the transmission medium whether the medium is RF or a DVD.
As a new scene emerges in a video program, the entire scene is transmitted at once using whatever pixel size is needed to convey the entire image at once, then the details are filled in by reducing the pixel size frame by frame until the entire scene is painted in at the intended resolution. Once the entire scene is sent, only the changes are sent in the following frames. In an average movie or TV show, the background of an image doesn't change much from frame to frame.
This works well as long as the total scene changes come at a rate slower than the average persons eye - brain system can resolve them. This is taken into consideration in the post production stages of most movies that are made for digital video.
The camera flash probably rails the A/D for a single frame, convincing the system that there is a new scene. The flash is over, then the old scene becomes yet another totally new scene. If this wasn't a live broadcast, the "flash" frame would be tossed out by the encoder, and you would never see it.
As with MP-3, understanding how MPEG4 and other video codecs work will clue you in as to what to watch for to see the system degradations. The previously mentioned sporting events, especially when the camera person pans across the crowd. Another big one is fire, especially when the fire occupies a good portion of the total image.
I worked as an engineer at Motorola designing radio and video systems for police and fire responders. About 10 years ago we were working on video transmission over what is now known as LTE. We were testing video for police and fire use, with several different video codecs. Our data rate was less than what it used currently for US HDTV transmission. We were using the movie "Backdraft" as out test video since it is all about fire.
So this is what you were all listening to.
The title of these was 'Just For Fun' and in a way that's all they are really. Now that you know what they are, you might be able to look back (or listen back 😀) and hear the effect/s for real.
The first track starts off as a direct rip but switches part way through to a lowly WMA of 128kbs. Listen carefully to the sibilance and the backing tracks around the area of the change. Its quite noticeable. I suspect some would perceive the WMA as 'preferable'.
SY's test track in many ways highlights the effects even better but in a different way I thought. The latter half of the track is the original master and that really does come across as more focused and a little cleaner. Listen to the vocals at the changeover point. Its quite an obvious change, almost as if the timbre has subtly altered. The master copy seems to have a slightly narrower but more focused width or soundstage than the compressed.
Again, thanks to all that listened and contributed.
(this thread raised questions for me... I was surprised that Audacity allowed two different file types to be worked on like this... but it seems it does. I even went as far as loading parallel tracks of different formats and bit rates and they all played simultaneously)
The title of these was 'Just For Fun' and in a way that's all they are really. Now that you know what they are, you might be able to look back (or listen back 😀) and hear the effect/s for real.
The first track starts off as a direct rip but switches part way through to a lowly WMA of 128kbs. Listen carefully to the sibilance and the backing tracks around the area of the change. Its quite noticeable. I suspect some would perceive the WMA as 'preferable'.
SY's test track in many ways highlights the effects even better but in a different way I thought. The latter half of the track is the original master and that really does come across as more focused and a little cleaner. Listen to the vocals at the changeover point. Its quite an obvious change, almost as if the timbre has subtly altered. The master copy seems to have a slightly narrower but more focused width or soundstage than the compressed.
Again, thanks to all that listened and contributed.
(this thread raised questions for me... I was surprised that Audacity allowed two different file types to be worked on like this... but it seems it does. I even went as far as loading parallel tracks of different formats and bit rates and they all played simultaneously)
Attachments
Yep, did not get back to this. And no wonder I didn't hear anything - I was comparing the beginnings of the tracks. Doh!
Will try again. Thanks.
FWIW, I've found that decent bitrate MP3 trends to sound a little warmer and more forward than the original. A lot of people like it. I can often Identify them by that. Low bitrate becomes obvious quickly on Jazz with all those splashy cymbals.
Will try again. Thanks.
FWIW, I've found that decent bitrate MP3 trends to sound a little warmer and more forward than the original. A lot of people like it. I can often Identify them by that. Low bitrate becomes obvious quickly on Jazz with all those splashy cymbals.
hard to judge audio quality on either track as the basic mix on both leaves alot to be desired in production terms.
for me the lack of kick drum and bass guitar on the first track with the female vocal just frustrates me and the second track with the male vocal that sounds like it's got a a bad flange chorus effect that kills any presence and sinks it behind the guitar part is annoying to me but that's me vocal out front and everything in persective from there!
i was unable to play the flac file.
for me the lack of kick drum and bass guitar on the first track with the female vocal just frustrates me and the second track with the male vocal that sounds like it's got a a bad flange chorus effect that kills any presence and sinks it behind the guitar part is annoying to me but that's me vocal out front and everything in persective from there!
i was unable to play the flac file.
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Karl, I'm curious about the Flac - I didn't bother trying to evaluate track 2, it just wasn't working well enough on the laptop - so "cheated" by loading both in Audacity, and comparing by subtracting one from the other. I was surprised to find that there was a near random noise floor difference between them, at about 70dB down - my understanding is that Flac is lossless, so I'm curious whether I did something wrong, or it's something to do with how you prepared the file?
I had to listen to track 1 a second time before i got the change point, still quite decent at the lower rate...
I heard the change over in track 2 first time, there does seem a bit of an improvement in clarity/focus all round.
Track 2 FLAC sounds the same as the master to me, but, is that because i expect it to 🙂
I heard the change over in track 2 first time, there does seem a bit of an improvement in clarity/focus all round.
Track 2 FLAC sounds the same as the master to me, but, is that because i expect it to 🙂
No worries 🙂 Quite a few years back I made a CDR of different bit rates and formats and by and large all were pretty good until you got down to the low numbers. I think its true that the compressed can come across with a bit more presence about them on some occasions.
(For low bitrates you need to hear the UK's DAB (digital radio service) which is based on MPEG-1 Audio Layer II (commonly referred to as MP2. That can be really grim, even on speech)
Hi Frank,
This was my first foray into using FLAC as I mentioned earlier. Once I was happy with the cut and spliced file (that the join was inaudible) I simply exported it twice from Audacity, once as WAV and then as FLAC. There was no manipulation or preparation of anything.
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Can I just confirm as confused. Are you saying you can't judge the quality because it's not music you like or because you prefer music thats been mushed to death in a studio?
It's often been reported that younger audiences complain that the orchestra doesn't sound like their hifi. I wonder if that is a similar case to be as the second track sounds to me like someone playing a guitar and singing. I'd hazard that he is sitting down as well. In that case the vocal should come from behind the guitar. To me it sounds very realistic. The acoustic sounds like a small room, but a solo guitar and singer without amplification works best in that.
I might be cloth eared, but to ME it sounds as I would expect it to be if I was sitting in front of the singer. Interested to know why you think that 'leaves something to be desired'.
i ran both tracks that i can play again on different speakers that i own (even swapped amps) to give it a more intent listen. after a few run through's when the tracks where becoming more familiar and i could change my focus away from the content and focus on the audio quality yes i could discern the change in audio quality. which to me is less discernible and less important than the production values used to produce these two tracks.
as someone who has done live sound(and some recording) i'm well acquainted with all manner of sonic differences my old ears might not be as golden as they once where but for me it's still the production.i've only heard the Toronto Symphony and Montreal symphony orchestras live a few times each but prefer the Montreal symphony at La Place des Arts because it a better hall acoustically.
as for the 2nd track with the male vocalist (on all playback systems i tried) the vocal seems buried(lack of midrange definition) by virtue of effects that where used on the vocal (the guitar doesn't seem to have the same "chorus/flange" that the vocal does which i would expect to be there if this was the result of acoustics of the recording environment and it was recorded live off the floor)
as someone who has done live sound(and some recording) i'm well acquainted with all manner of sonic differences my old ears might not be as golden as they once where but for me it's still the production.i've only heard the Toronto Symphony and Montreal symphony orchestras live a few times each but prefer the Montreal symphony at La Place des Arts because it a better hall acoustically.
as for the 2nd track with the male vocalist (on all playback systems i tried) the vocal seems buried(lack of midrange definition) by virtue of effects that where used on the vocal (the guitar doesn't seem to have the same "chorus/flange" that the vocal does which i would expect to be there if this was the result of acoustics of the recording environment and it was recorded live off the floor)
I believe that there were no effects used and the recording was a single stereo microphone in front of the performer. As 'unproduced' as you can get. Anything you hear is as a result of room acoustic and mic positioning. SY can confirm.
Confirmed. No mixing, eq, compression, colorants, additives, or GMOs. No animals were injured during the production of this song.
Think I understand what turk 182 means. It is hard to evaluate the playback with the added colouration caused by the room acoustics. It sounds like a busker playing in a supermarket. The same problem with the classical recordings. You don't only hear the music, you also hear the room and it get in the way.
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