TRUE BITRATE - how to calculate bitrate of mp3

here i wanted to point out a quick way to check the true bitrate of any mp3 file, i.e. how to calculate the bitrate of mp3s in case you are suspicious about not getting the full sound. up-encoding has become a nasty tradition of direct downloads sites like mixing.dj, livesets.at, edmtunes, etc. those sites are after money, they are not true to the high quality music, they push over-encoded bloated mp3s onto you, and you take them, and store them on your hard drives, and end up having lost 150% of storage space in too many cases.. why they do it? cause they get more money if you download a file over 100mb from the hosting service, thus a true 128kbps encoded file will be up-encoded by them into a false 320kbps mp3, because 1hr (average mix length) of 128kbps is only 55MB, and 1hr in 320kbps goes easy 137MB - well over 100.

thus i wanted to educate you a bit on how to catch such mp3s. we on tribalmixes try to deliver the pure quality straight bitrate mp3s, so if we see 128kbps file we will deliver it as is, we don't want to waste anyone's bandwidth, including our own. here's how you can easily spot false transcoded mp3s:

1. easy to use free tool AUDACITY https://audacity.sourceforge.net/download/ install and check it out real quick..

2. find two mp3s on your computer that you know for sure are true 128kbps and 320kbps, best - record some CD in 320 and 128, then you'll know what bitrates you got for sure

3. open both mp3s in audacity, now select a small piece of 2-3 minutes of sound on one mp3, go to menu ANALYZE and there click PLOT SPECTRUM. check out the picture. note what values are on the scales, see how graph ends, where it touches the axis. do the same with the other mp3.

3.a. for 320kbps values will be something like -6dB and 20000Hz, see how full the spectrum is and how graph is rather uninterrupted curve

3.b. for 128kbps values are -18dB and 10500Hz, note how graph goes nicely curved and falls off in the middle

4. repeat steps with other mp3s of true bitrate you're aware of, check 192 and 256 kbps mp3s, or even some VBR ones

5. take the suspicious mp3 in question, open it, analyze it. with false 320kbps you will see the drop as was in 128kbps, or 192kbps (these also happen to be transcoded), sometimes there will be some gain of graph after the drop, that actually illustrates the sound of unknown origin that software somehow added to the normal 128kbps sound, but in most cases drop will end up being 0 after the middle

6. if you were going to share that dj mix on tribalmixes - make sure to save it with true bitrate and go ahead and share it! =)

i'd like everyone now get the tool, try these steps, very easy and very educational, and noone will be ever able to "sell" you their low quality mp3 as top high quality 320kbps master copy.. if you do these steps and find some mp3 in your collection being over-encoded - make a screen-shot of the spectral graph, post it in here, with the name of the mp3, so that others could see and learn from the picture.

i am planning to expand article this into something huge... if someone is interested to help... how about a Global EDM Downloads Sites Comparisson on the subject of TRUE BITRATE? we could to a series of tests and make a rating-list in order which site provides more correct mp3s with proper bitrates? for that, we could download 10 mp3s from each of the biggest sites, randomly selecting 1hr long mp3s, download them, preferably take only 320kbps files, then we run these spectral analysis on each of the mp3s, and see what the true bitrate really is there, and get the final score like 4/10 - meaning 4 were true, 6 were falsely saved...  anyone interested in helping me out?

Will defintely check it out slash, cheers for the concise headsup!! Not around after Sunday for four weeks mate, so will have to come back to it after my course mate!!!

sticky this

i may find some time, may not, but if i find i can forget, so would be nice to see it on top and remember

Slash,

Thanks for the initiative!


I'd like to take on this task of helping with this subject.    


I'll contact you so I don't write an unnecessary 4 page novel... yet!  


Cheers.  




_________________________
I added cool smileys to this message... if you don't see them go to: https://s.exps.me

We all know that`s crap mallam, its a miracle you get out of bed in the morning  

well, i wasn't gonna do too much theory anymore, that was as good as it gets for me, you know, it's enough to figure out true bitrates, thus it's enough for me.. i was just gonna do a cross-comparison of all the biggest sites to see who's doing the best, i already know we are, or maybe tmb, but with spectral graphs and a dozen other sites such a document could look impressive.. =)

one of the good examples of how direct downloads sites want to fuck you over.. read on in this torren there https://www.tribalmixes.com/torrent/77971-Sensation-Innerspace-Serbia-12-may-2012 the description. in 2 words: besides 5 official mixes from Sensation: Serbia 2012 released by Sensation on soundcloud, there's 6th mix, which is a bad quality off air recording of Fedde Le Grand; file's size is 103MB, it has 25 minutes of bad quality music, and 20 minutes of silence after that, which all together saved at 320kbps allows for a file which is larger than 100MB, - exactly what those sites are after, 100mb files, more money, more income, more penis up their users mouths and asses. yes, continue using those sites, and you will someday definitely feel their penis in your mouth as well. or maybe in your ass. i don't know the way you prefer to be penetrated by those sites.. i do know that tribalmixes will never try to do that to you, we are not fags, yes, direct download sites owners, you read right - you're all fags for playing your 100mb+ game.

there are links to pages on at least 2 leading direct download sites in that torrent description, you can check it out for yourself, i mean, check out the 25minute long nasty sounding audio that is 103MB huge.

Mallam, finds it hard enough to enter passwd's thank goodness for cookies.. as he would never log on!!!

Slash, I like your attitude mate!!! LOL!!! Striaght out of my book!! There is a crazy ivan beneath that cool, calm, helpful exterior!!!  

I now know why Mallam has been slacking... he has spent the last how many days thinking and designing his new "slack" signature...

hehe,, i just haven't smoked yet... =) but it's true and awareness must be raised somehow..

This will be a little weekend project for me.  Nearly all of my mp3s are from here, though, so I do not expect any shadiness.

This topic is a bit more complicated than I think most realize.  


Slash is absolutely right above, but only to the extent of verifying whether a 320kbps file is "real."  


Discovering the true bitrate, however, is where the true difficulty remains.  


Or, as munkyn & Andy would say, "slacker!"  

True . . . I'm literally averaging 2 hours of sleep a night now!  

At least you are honest....