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Some Basic Questions from MP3 noobie

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GeeJay:
 :-X :-X
--- Quote from: Mr Whippy on December 21, 2011, 06:01:47 AM ---if you're ripping CD's I'd encode them to flac tbh. For CD's I'd recomend Exact Audio Copy and flac encoder. Also could record your tapes to flac as well.

Since you're going to have a lossy copy for portable use, you could experiment with different codecs and bitrates then settle for one. That way you have your lossless flac copies already at hand.

Also you may be able to get the albums you sold cheap on CD

--- End quote ---

Perhaps you missed my intro where I stated "I am an old f*rt ....".   This is the first time I have seen terms like "flac", "codecs" "bitrates" "lossy" and "lossless" so I went Google to find out what you are talking about.  I now get the idea but will have to do some research on this.

As a fulltime RVer,  I want to put my CDs and Cassettes on my computer in MP3 format primarily as a physical space saving exercise, so portability is secondary.  I still have a high end Sony Walkmans (with Dolby NR) and Discman, but do like the minimal size of the MP3 players

I have about 450 albums on cassettes so buying new CDs for these albums   would cost in excess of$5000. MP3 downloads would cost less than half the cost of the CDs and would not take up space in our RV. Wouldn't that be more viable?

BTW I have  purchased 2 Sandisk Sansa Clip Zips, 8GB, so I will be able to start playing MP3s as soon as I have some.

Thnx for the input to date.

GJ

werich:
Hello GeeJay,

as people mentioned before ripping analogue material is not recommended only as last exit. It's definitely worth to acquire your most beloved music again in a digital format (either as CD ripped with Exact Audio Copy, so the CD stays as backup - or the easiest way buy mp3's, but make sure to do some backup on an external harddisk then).

But surely some recordings are unique or rare - here is an step-by-step explanation for recording using a free software http://www.online-tech-tips.com/computer-tips/transfer-audio-cassette-to-computer/. Unlike recording with cassettes it's VERY important never to exceed the (red) VU recording level meters (not even a bit), which produces terrible distortions! As you see possible "clipping" only after you recorded the whole part, this is somewhat tricky and time consuming. And don't expect wonders in quality - the computer recordings always sounds worse than directly from the cassette player.

To save the recordings in MP3 format you have to install the free "lame MP3 codec" as well http://www.free-codecs.com/download/lame_encoder.htm. Copy the files in some folder - the recording software will probably ask the 1st time for the location of "lame_enc.dll" which is included in this package. With the free software "mp3directcut" http://mpesch3.de1.cc/mp3dc.html it's possible to cut a 45minute MP3 into single parts - by hand and also by automatically detecting 4s pauses inbetween the songs.

In General:
As for the codec and bitrate there are many opinions there. A freshly recorded uncompressed WAV file (40 minute in CD quality, 16bit 44kHz) consumes about 425MB. From my experience a lossless format like FLAC is far to overdone for the relatively worse quality of compact cassette and consumes much space (about 50% of the before mentioned uncompressed WAV format). The most compatible MP3 format starts from 128kBit/second (40MB per 40 minute Album, worse quality) over 192kBit/s (60MB per Album, reasonable quality) to 256Kbit/s (75MB per album, good quality) up to 320 kBit/s (96MB, insane quality). In terms of quality vs. size this is a somewhat logarithmic scale, so there is much more improvement from 128 kBit to 192 kBit than from 192 kBit to 256 kBit. If you choose variable/average bitrate (VBR or ABR), simple structured parts get a lower bitrate, complex parts a higher one, so that at the end the average bitrate matches your setting. Using a psychoacoustic mathematical model, the best MP3 bitrate strongly depends on the kind of music you are referring to - live or analogue recordings and speech don't get so much better with higher bitrates. Very dynamic classical music or jazz ripped from a CD at the other hand could'nt be coded high enough, and I really would consider using lossless formats like FLAC or at least more effective codecs like OGG Vorbis.

But always try to save the best quality first and occasionally convert it down to a lower quality codec and bitrate (to fit your 8GB Sansa Players). In times of terrabyte harddisks for around 100 bucks, I would hold both: high bitrates or even FLAC for the "raw" cassette recordings (lot of work is in there) at my computer - and down-converted MP3 with no more than 192 kBit/s for using on the the Sansa player. Always encode from the best source quality and try to avoid transcoding from one lossy format to another. I myself fitted 30% more albums on my player using Ogg Vorbis 140 kBit instead of 192kBit MP3 on my rockboxed Sansa Fuze.

Hope that helped and a happy new year
werich

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