md8 compression

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gbrigman

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i've read so many posts regarding compression (atrac) on the md8 - it appears to me that everyone is confusing this with musical compression - i got some info from a guy who runs a studio in europe and it confirmed what i already thought - it's disk compression just like used in computers - not musical - and atrac doesn't filter any muscial sounds or change their sine waves in any ways - it basically eliminates blank space - now i never used anything with atrac 1.0 but the current md8 and atrac compression is a non-issue.
 
Sorry, that's COMPLETELY wrong...

ATRAC compression is a lossy data compression scheme the algorithms of which are based on removing portions of the frequency spectrum that are masked by other frequencies. It is NOT the same as "musical" compression, but it DEFINITELY changes the original waveforms...... and it has nothing to do with "blank space."

That being said, the algorithms are quite good, and the results are far superior than to say, cassette. But it is NOT up to even CD quality, let alone above that...

Bruce
 
compression

it removes blank empty space - as far as cd quality - ALL CD Recorders change the sound - that's why major acts spend 100k+ on a recording (digital) then go back in and master it (doing every trick in the book) to make it sound analog - WARMTH -

by the way - it's not wrong - it doesn't change the sine waves of the music - there are studios in europe who have basically proven this by the use of expensive spectrum & frequency analyzers -

you guys use the compression as an excuse - you can get release quality recordings from the md8 without a whole lot of effort if you know what you're doing -

and for the money the md8 costs - it's an incredible piece of equipment
 
compression

oh i forgot to add - the engineer from europe also stated that NO compression is used on the outs - anything coming out from the outputs is not compressed - compression is only used when writing to disk - he also stated that this was verified by yamaha
 
Dude...

You have a LONG way to go before you even BEGIN to start understanding record engineering it seems..... but hang in there, one day, you may pick it up....

Bruce
 
compression

nah ray - no pissin' match - and hey blue bear - guess you're right - i've been in the business for 27 years with
3 lp releases word wide and more to follow - have also done tons of studio work over the years - don't you have anything postive to add or you just like to hear yourself talk shit
 
And apparently, with all that experience, you never learned a thing about engineering......

There isn't a sound engineer in the world that would consider the minidisc as a viable mastering format....

So much for your "experience".......

But whatever - you do what you like.... arguing this with someone so obviously less knowledgeable isn't worth the effort... you could go discuss the merits of studio monitors with "Cathy" in another thread - she may be more on your level of understanding....

I'm out of the pissing contest...
Bruce
 
First, Bruce is right. Blank space has nothing to do with ATRAC. It uses psychoacoustic principles (such as masking) to compress the data rate. Through a combination of bit allocation algorithms, splitting time frequencies etc, the MD takes advantage of these principles in a very effective way, thus producing decent quality audio.

Even Sony, who came up with the Minidisc and ATRAC, doesn't try to make people believe that MD-quality can compete with pro recording gear. They described it with 'virtually no loss in sound quality' back when the 1.0 version came out. IE compared to CD quality. Nowadays, some will acutally argue that ATRAC 4.5 sounds better than a CD. True? I dunno. Do i care? Not really. Can you accomplish good sounding recs on a MD8? Homerecs? Demos? I'm sure you can. Will major pro studios go MD? No way! Will your local 8/16/24-studio dump their ADATs for a bunch of synched MD8s? Nope.

MD is a great complement to consumer CD and a more than worthy successor to the cassette, in stereo recs as well as low end multitrack recs. People seem to forget that the MD was made to be convinient and portable while maintaining a very decent quality of audio (be it MD audio or MD-Data). If anyone wants to record their own CD using an MD8 - hey, go ahead. It's your material, do what you want with it.

BTW, gbrigman, three world wide LPs in 27 years. You have a very patient A&R guy. When is your next creation due? Since i don't reside in the US, will it also be world wide?

micmac
 
comperssion

blue bear -you haven't a clue !!!

you and mirmac need to contact european engineers who have researched the atrac comperssion system (independant sound lab analysis - yes there is such a thing but i guess you guys wouldn't know about that )

as far as using the md8 for a mastering disk - if you read previous posts that's the exact opposite of what i said - the basic recordings go into a mastering lab for mastering - i wouldn't use an md8 to finish off a recording.

3 lps in 27 years - you're right - i dropped out for awhile - had a kid - 7 figure medical debts - music went on hold until i could pay it off -

as far as a pissing contest with blue bear - he has nothing to piss with - he's a complete idiot who likes to hear himself and smell his own shit - nothing concrete

by the way - if you look hard enough - you'll see i've had stellar reviews in spin,musician,cream,rolling stone etc.etc. - oh that's right - you already know everything - by the way - how come i've never read ablut you ??? or see any of your previous releases for sale - saw my first lp listed for $500.00 us - but it's gone - somebody bought it - how about that - it usually only goes for 350.00

so shall we just try and keep up with the insults - or have you fragile egos had enough for awhile - or until you decide to jump on someone else
 
oh i forgot to add - if the md8 is such a piece of crap - why / how could someone so smart as yourself use such a machine ???
 
gbrigman,

Respectfully,

I've used the Yamaha MD4S, but my main experience with MD's stems from extensive use of Sony MD-decks and portables. The MD4 (and the MD8 also i'm sure) is a really good portable MTR, nothing more, nothing less. It's way ahead of PortaStudios and other tape based low end MTRs, but try to match any MD against quality gear recording at 24bit/48 or 96khz and it's game set match the latter. I love using MD's, but they're just not up where i think you want to put them.

I first got into MD's back in March 1993, when i sat down with then marketing director of Sony Music Sweden, who gave me a copy of Toto's 'Kingdom of Desire'. Sony was trying to market the MD but the other big record companies got scared shitless because they thought their profits were at stake if people could copy CD's with digital sound quality. That's why MD never really took off in any other countries than Japan and few other in south east Asia. All the major companies except Sony went on to support Philips DCC system, as they thought it wouldn't be a very convenient format anyway.

Why am i telling you all this? Well, when i heard what was happening i kinda dug into MDs and how good they actually were/are and why the record companies were so uptight about the whole thing. As for how it really works, i recommend reading what Mr. Tsutsui and his colleagues at the Sony Research Lab wrote about it back when they presented it at the AES convention. The paper is somewhere at www.minidisc.org if they haven't removed it. It's a very technical piece, but you'll understand that ATRAC is not about eliminating blank spaces.

I did some A/B-testing a long time ago, and i still do it with people when i get a chance, just to see if they can tell the difference between a CD and an MD. Although i will never claim that my testing is scientific in anyway, there are obvious consistencies. People who are not recording professionals clearly have tendencies towards a 50-50 accuracy. Some of the music professionals (mainly musicans and sound engineers) that i've asked to do this have come close to 100%, but only a few have nailed 10 out of 10. I haven't tested anyone with ATRAC 4.5. BTW without question, the funniest test was when a friend's friend who's an 'audiophile' got 3 out of 10 and then gave me speaker cable for birthday present...

gbrigman, based on facts that i've gathered and on my experience when it comes to MD's i disagree with you on the sound quality of minidiscs and how ATRAC works. I do not think that MD8's are crap, nor do i think they are top quality these days. But MD's in general sure are getting very, very good.

micmac
 
Re: comperssion

gbrigman said:
blue bear -you haven't a clue !!!

you and mirmac need to contact european engineers who have researched the atrac comperssion system (independant sound lab analysis - yes there is such a thing but i guess you guys wouldn't know about that )

as far as using the md8 for a mastering disk - if you read previous posts that's the exact opposite of what i said - the basic recordings go into a mastering lab for mastering - i wouldn't use an md8 to finish off a recording.

3 lps in 27 years - you're right - i dropped out for awhile - had a kid - 7 figure medical debts - music went on hold until i could pay it off -

as far as a pissing contest with blue bear - he has nothing to piss with - he's a complete idiot who likes to hear himself and smell his own shit - nothing concrete

by the way - if you look hard enough - you'll see i've had stellar reviews in spin,musician,cream,rolling stone etc.etc. - oh that's right - you already know everything - by the way - how come i've never read ablut you ??? or see any of your previous releases for sale - saw my first lp listed for $500.00 us - but it's gone - somebody bought it - how about that - it usually only goes for 350.00

so shall we just try and keep up with the insults - or have you fragile egos had enough for awhile - or until you decide to jump on someone else

Hey asswipe.......... so you put records out -- big deal.... it hasn't taught you shit about engineering apparently! There are an awful lot of bad-sounding albums out there too....

--------------------------------------------------
If you're too damn lazy to search for it, here it is - right out of the book:


4.What is ATRAC exactly? How does it compare to PASC?

ATRAC (Adaptive TRansform Acoustic Coding) divides the 16 bit 44.1 KHz digital signal into 52 sub-bands in the frequency domain (after a Fast Fourier Transform). The sub-bands in the low frequencies are finer than the ones in the high frequency range. A psycho-acoustic transfer function that takes advantage of the masking effect and the absolute hearing threshold then removes enough information to reduce the data stream to 1/5th of the original size. Each channel receives that treatment separately (the Sony MZ-1 portable MD recorder features one ATRAC encoder/decoder chip per channel). PASC (Precision Adaptive Sub-band Coding -- used in Philips now defunct DCC [Digital Compact Cassette]) divides the digital signal into equally spaced sub-bands and removes less information (to only 1/4th of the original size). PASC is essentially the MPEG Layer 1 audio standard (can be decompressed with MPEG Layer 1 players after a trivial preprocessing step).

Both are data compression algorithms, used to store the information content from a stream of 16-bit samples in fewer bits. The purpose of compression is to reduce the rate at which the disk has to deliver or record bits, and to reduce the total number of bits stored. There are many compression algorithms. The ones used for computer data (for example in archiving programs) are lossless; the result of decompression is identical to the input.

PASC and ATRAC are both "lossy" algorithms. In order to get greater compression, they do not attempt to preserve every bit of the original data, but rather only the acoustically "important" bits. Considerable cleverness goes into finding the sounds masked by properties of the human auditory system, ones that you would not hear even if they were reproduced. By all accounts the two schemes do amazing well, considering they operate in real time.

...

17. Is there any loss of information when I record from a CD?

There are two sources of distortion. One is the chain of components that brings the sound to the MD's input. If you go analog-to-analog, you introduce the CD's DAC and the MD's ADC chips, each with its own artifacts. However, you can ring the digital data stream directly to the MD; then the only source of differences is the ATRAC compression algorithm.

The ATRAC encoder removes information from the audio material in order to store it on the MD (5: 1 compression with loss). To make better MD recordings from CD, connect the MD recorder to the CD player via a digital connection (if possible). Thus, the ADC (poor in the first generation machines) cannot affect the sound quality. Otherwise, when recording via the analog input, make sure to adjust the manual recording level on the MD machine so that the meter peaks just above -12 dB (on the Sony MZ-1, never enable the AGC for CD recording).

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So as you see, you no-talent-waste-of-space, you are completely dead-wrong about what you think MD compression is all about.... so fuck-off, beleive what you like... and continue putting shit out "mastered" (sic!) on minidisc format..... I really don't give a rat's ass what you do!

Bruce
 
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