Lower bit-depth-rate conversion... how to get what's lost back?

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Pinnipedal Czar (: 3=
Member Since: Apr 11, 2004

I either asked this in another thread a while back and can't find it to see if anyone had anything to say about it; OR I attempted to start this thread, here from work once before, and ended up deleting it because something came up.lol So... I figured I'd just start another to ask all here for any answers they may have. I am sorry if that, in itself, caused any inconvenience for anyone.

The scenario...
When I upload a song here on HRC, it's relatively high resolution makes for fine listening, and for the most part, all of the song seems intact.(there is some slight loss) On the other hand, on our bands website, where we upload at a lower resolution,(not sure of exactly just how low... a Went thing) and the difference is quite noticeable... across the entire audio spectrum.

The questions...
Is there anything that can be done to the material, either prior to or directly after, that will help restore those frequencies which are lost in the conversion process, or is it just a case of those freqs not being supported by a lower bit depth rate?

These questions are obviously brought about by my ignorance of exactly what it is that takes place durring audio conversion, so if someone here could explain the process to me... that'd be swell, as well. : )

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Czar of Turd Polish
Member
Since: Jun 20, 2006


Jul 28, 2009 01:18 pm

I understand it as I did a presentation on bit and sample rate and it's affect on audio in school, I don't have that power point laying around so I'm not going too in depth. There are certain apps/hardware I have seen recently that state it brings back those freq that were lost but really it's just faked as the true tone is lost forever (without the master of course). For online I try to encode at a minimum of 256 for mp3 unless crammed for space.

Anyway, for visual sake let's focus on .wav files

If you take 44100Hz audio and draw a line of how many times it samples per second you would get a smooth wavy line that rises and falls. Lower the smapling per second (22000hz) and you start to see stair stepping in that line and it is no longer smooth. Those points are where the loss occures. Reduce it more and you lose more. This is just a rough/crude explanation but should give an idea. This is more in regards to sample rate but bit rate will result in a similar result.


http://img151.imageshack.us/img151/1273/bitrate.jpg



With .mp3 I believe the extreme high end is discarded to save space and then all the rest is compressed. On this I am not 100% sure, but that is what I understand at this point.


Pinnipedal Czar (: 3=
Member
Since: Apr 11, 2004


Jul 28, 2009 02:45 pm

thanks Cap'n!

I wonder how that soft/hardware you mentioned sounds?.. How well does it do what it says it does?

Typo Szar
Member
Since: Jul 04, 2002


Jul 28, 2009 08:35 pm

I think the loss u hear on conversion to websites is not a loss in resolution, i could be wrong. but its usually that websites such as myspace and youtube have their own compression algorithms, so when ur feeding in an mp3 (which has already begun to degrade the audio) their harder compression is giong to degrade it even less.

Hold 'Em Czar
Member
Since: Dec 30, 2004


Jul 28, 2009 08:52 pm

Quote:
Is there anything that can be done to the material, either prior to or directly after, that will help restore those frequencies which are lost in the conversion process


undo.

sorry had to say it, lol

as for what crux just said, i think he's right here...do you have the same file you uploaded to both sites? was it the same file, if so, then you can chalk it up to the websites player.

Pinnipedal Czar (: 3=
Member
Since: Apr 11, 2004


Jul 28, 2009 09:16 pm

I am at a loss as to imagine just what my words may end up meaning, in response of that comment, Dad.

Seriously though... No, errr... yes, it's the same file... at a lower rate... so, it's different... kind'a, so... no, it's not the 'same', really.


What Crux said, makes much sense.

Czar of Midi
Administrator
Since: Apr 04, 2002


Jul 28, 2009 09:44 pm

The thing is once its converted you cannot get the higher quality back into the file. Only the original file will retain the higher quality.

Hue, find out what exactly Went is converting it down to. He might be going to far down.

I never go any lower then 128 for mp3 at all when putting it up for streaming.

Typo Szar
Member
Since: Jul 04, 2002


Jul 29, 2009 07:15 am

just FYI, i remember reading somewhere that mastering houses many time create masters specifically for internet streaming tailored to each popular web service, one of their recommendations was to back off on compression and limiting ur track

the players have their own compression algorithms and volume is not such a big issue on most streaming websites, so leave alot of ur dynamics and movement intact, coz their only going to be taken away.

Pinnipedal Czar (: 3=
Member
Since: Apr 11, 2004


Jul 29, 2009 07:46 am

Noize, I do believe it is just that... too low. I found out last night, just how low, and it is amazing that it is intact as it is... those puppies are streaming at 32! lol "The lowest we can go.", was how he put it.

Luckilly, we found a way to get around that... Reverb Nation! What an awesome site that is, indeed. They allow for the higher rates needed.

Quote:
the players have their own compression algorithms and volume is not such a big issue on most streaming websites, so leave alot of ur dynamics and movement intact, coz their only going to be taken away.


That sounds like a good strategy, even at the higher rates. Def something I will try.

Thanks, you guys!

Czar of Midi
Administrator
Since: Apr 04, 2002


Jul 29, 2009 08:28 pm

OH CRAP!!!!!!!

That is way to low.

Pinnipedal Czar (: 3=
Member
Since: Apr 11, 2004


Jul 30, 2009 01:58 pm

Bah! Yeah, after I heared that, I was more impressed as to how well they held up, instead of being disappointed with how much was gone. haha The mind is a funny thing!

But, since we're stuck there for a while, we've remedied the issue by going to Reverb Nation as our player-platform. THAT site is a beautiful thing! Everything that up and coming bands need.

Czar of Midi
Administrator
Since: Apr 04, 2002


Jul 30, 2009 08:03 pm

I must say it sounds better then I would have expected at that bit rate.

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