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Subject: Re: AW: Question about CD-Quality and MP3

Re: AW: Question about CD-Quality and MP3

From: Rocker <rocker_at_shaw.ca>
Date: 2006-02-03

Hi you wrote:
Mine cost me £10 (what's that, about $96 ...LOL, sorry) at a local guitar
shop ...I was AMAZED at the quality for what I think is such a low
price. Even "foamies" can set you back a couple of quid per pair some
places.
*True I pay five bucks or about 1 quid LOL! for tree pair of foamies. What
is the exact model, if there is such a thing, of your plugs?

rocker

----- Original Message -----
From: "Bluechip" <csbluechip@gmail.com>
To: "Rockbox" <rockbox@cool.haxx.se>
Sent: Wednesday, February 01, 2006 10:02 PM
Subject: Re: AW: Question about CD-Quality and MP3

At 03:33 02/02/2006, you wrote:
>Hi you wrote:
>I can whole heartedly recommend the etymoic ear-plugs - they claim a flat
>response - but as sound is perceived by more than the ear (especially with
>a KW or 2 of fold-back aimed at your head) the flat response is not really
>likely. They are however, inconspicuous to the degree that people looking
>into your ear and shouting requests fail to realise why you can't hear them
>(repeatedly). They can be "screwed in" like a volume control. They don't
>disagree with sweat. They are so comfortable you could _live_ with them in
>place.
>
>Cheers man. I'll check those out. I am just using drug store foamies and
>while they work they do take a lot of feel out of my playing. Well I guess
>it's back to EBay again...rocker

Mine cost me £10 (what's that, about $96 ...LOL, sorry) at a local guitar
shop ...I was AMAZED at the quality for what I think is such a low
price. Even "foamies" can set you back a couple of quid per pair some
places.

>----- Original Message -----
>From: "Bluechip" <csbluechip@gmail.com>
>To: "Rockbox" <rockbox@cool.haxx.se>
>Sent: Monday, January 30, 2006 7:51 PM
>Subject: Re: AW: Question about CD-Quality and MP3
>
>
>At 02:23 02/02/2006, you wrote:
> >To many years in front of a Hi-hat eh? I sure knows what that's all
> >about
> >dude. My right ear has lost about 20% of the highs. I used to play a
> >Tama
> >Imperial Star kit using Quantum 3000's with no ear protection. I'm still
> >using the Quantum's but I have a real kit now. And ear protection all
> >the
> >way man. Don't want to become a member of the deaf blind community.
> >LOL!
>
>LOL!
>
>I can whole heartedly recommend the etymoic ear-plugs - they claim a flat
>response - but as sound is perceived by more than the ear (especially with
>a KW or 2 of fold-back aimed at your head) the flat response is not really
>likely. They are however, inconspicuous to the degree that people looking
>into your ear and shouting requests fail to realise why you can't hear them
>(repeatedly). They can be "screwed in" like a volume control. They don't
>disagree with sweat. They are so comfortable you could _live_ with them in
>place.
>
>What a shame I did not discover them until it was too late :(
>
>One day I will have the cash to check out their headphones :)
>
> >My hearing is still real sharp and I can definitely tell the diff between
> >128 and 192. So, 160 is likely in-between that.
> >
> >I think you also need to consider the source as well. Everything from
> >tracks to mixing to mastering will have varying levels of compression
> >already applied. We recorded at a basement studio once where the guy
> >applied so much compression that when we spun are stuff on a local INDI
> >rock
> >radio show the sound was brutal. FM radio applies even more compression.
> >No 128 bit for that crap. Like Blue Chip says, experimentation.
> >
> >rocker
> >
> >
> >rocker
> > ----- Original Message -----
> >From: "Bluechip" <csbluechip@gmail.com>
> >To: "Rockbox" <rockbox@cool.haxx.se>
> >Sent: Monday, January 30, 2006 5:57 PM
> >Subject: Re: AW: Question about CD-Quality and MP3
> >
> >
> >A friend of mine encoded the same (chosen to be complex) track and
> >compressed it at everything from 128...320 ...It was his (non-musicians
> >(and he knows that)) ear that said "at 160 I personally couldn't her the
> >difference, so I went with 192 - the next one up."
> >
> >I am a musician - albeit with a hearing problem (too many years in front
> >of
> >a hi-hat) ...and my take is: I can tell the difference at 160 ...but I
> >use
> >my mp3 players 1) in the car, 2) as a walkman, and 3) background music at
> >parties ...If I want to listen to CD quality I listen to a CD ...There is
> >soooo much background noise in car/street/party that you're not going to
> >hear errors in the compression (loss of treble, bass, patterns in the
> >(psuedo)random-noise, hissing cybals etc.) ...So my CD collection has
> >been
> >compressed at "160/44.1/joint-stereo/quality=0 (highest)/optimise for
> >quality"
> >
> >In honesty though mate, the only way to know the point where YOUR brain
> >can
> >identify the errors is by trying compressing one track at lots of speeds
> >and sending yourself slightly mad listening to them over and over again.
> >
> >Best thing is get a friend to put them on the CD in a random order. Sit
> >down, blindfolded and mark the tracks out of 10. Decide where how far
> >from
> >10 you are prepared to accept (given where and when you will listen to
> >the
> >jukebox). And the answer will be there in front of you.
> >
> >For a laugh put multiple copies of each bitrate on the CD ...include the
> >original uncompressed version ...see if you give identical files
> >different
> >marks ...if you did - take the highest mark for any example. (Ie you give
> >the 160 8/10 the first time around, and 6/10 the second time around
> >...either you have sensitised your ear to the errors, or you are
> >imagining
> >things. If it's THAT close a call - then 8/10 it is!)
> >
> >BC
> >
> > >Hi Rob
> > >
> > >Thank your verry much for your detail infos. I have yet i hope a last
> > >question:
> > >On witch samplerating and hz you can't hear definitly the different
> > >between
> > >a Sound on a CD and sound on an MP3-File?
> > >Somebody thinks, that a compression with 224 kbps, 44100hz, VCR-Level 4
> > >it's
> > >sufficient to reach the CD-Quality.
> > >
> > >Some tests and knowhow can be verry interesting.
> > >
> > >Greetings
> > >Selamet
> > >
> > > > -----Ursprüngliche Nachricht-----
> > > > Von: rockbox-bounces@cool.haxx.se
> > > > [mailto:rockbox-bounces@cool.haxx.se] Im Auftrag von rob powell
> > > > Gesendet: Mittwoch, 1. Februar 2006 11:11
> > > > An: Rockbox
> > > > Betreff: RE: Question about CD-Quality and MP3
> > > >
> > > >
> > > > Hi,
> > > >
> > > > Not sure I understand the question entirely, but here's some help.
> > > > Hopefully it'll be of use to others too.
> > > >
> > > > These comments are obviously not all-encompassing, but they
> > > > do to gain an
> > > > understanding. There are 2 elements to the quality of a
> > > > digital audio file,
> > > > whether it be MP3, Ogg, or whatever. Sample frequency and bit rate.
> > > >
> > > > First, professionally produced audio CD's are always sampled at
> > > > 48KHZ,
> > > > whereas most MP3's and minidisks tend to be sampled at 44KHZ.
> > > > Second is the
> > > > bit-rate, not so critical as the sampling rate, but still
> > > > important. Most
> > > > MP3's are recorded at 128KBPS, (kilobits per second), though
> > > > of course you
> > > > can record at whatever value you want, provided your MP3
> > > > player will support
> > > > it). I for example record books at 48KBPS, 22K sampling
> > > > rate, and mono.
> > > >
> > > > It's generally agreed however that to obtain CD quality, you
> > > > need to be
> > > > recording MP3's and any other audio format for that matter at
> > > > 192KBPS. For
> > > > reasons that I'll go on to explain, it's not actual CD
> > > > quality, but it's
> > > > recognised to be audibly very close, and barely noticeable.
> > > >
> > > > There are basically 2 types of digital audio formats, lossie
> > > > and lossless.
> > > > Lossless create larger files, lossie ones smaller. .MP3 .ogg
> > > > and .wma are
> > > > examples of lossie formats, .wav is a lossless format. The
> > > > issue is not
> > > > whether you loose anything by converting to MP3, but whether
> > > > you'll notice
> > > > what you loose on the equipment you're using for playback.
> > > > 44KHZ and 128KBPS
> > > > are generally recognised to provide an adequate level of playback
> > > > for
> > > > portable digital audio devices, and indeed I find that
> > > > generally to be true:
> > > > however when I connect the Archos or Iriver to my hifi
> > > > system, I can hear
> > > > the difference quite easily between the CD and the music on my
> > > > player.
> > > > Basically it's horses for courses.
> > > >
> > > > Inevitably however there's a trade-off between file size and
> > > > quality. You
> > > > don't actually need an audio book (speech) to be the same
> > > > quality as your
> > > > favourite album: so you can get away with lower bit-rates and sample
> > > > frequencies, which mean smaller files, and less space on your
> > > > MP3 player. I
> > > > change the bit-rate and sample rate quite a bit, depending on what
> > > > I'm
> > > > recording. Old football matches recorded from AM don't need
> > > > to be recorded
> > > > at a high bit rate and sample frequency, as the bandwidth of
> > > > AM limits the
> > > > quality of the original. Well-recorded stereo radio dramas
> > > > however benefit
> > > > from higher recording quality.
> > > >
> > > > The generally accepted rule is, that the MP3 standard is good for
> > > > many
> > > > reasons, not least because all digital music players will
> > > > play it. However
> > > > Ogg Vorbis WMA and others have advantages. Ogg Vorbis files
> > > > take up less
> > > > space for the same sample and bit-rate size. It's also a more
> > > > modern
> > > > encoding standard, and therefore the quality of a file will
> > > > be higher if an
> > > > MP3 file and an Ogg Vorbis file of the same size are
> > > > compared. However a
> > > > .ogg file and an MP3 file recorded at the same bit-rate and
> > > > the same sample
> > > > rate will be of very similar quality. That's as I understand
> > > > it, if I've
> > > > got it wrong, I'm happy to take corrections: as I'm a bit hazy
> > > > there.
> > > >
> > > > Gary, you might know more.
> > > >
> > > > I think that all the units that'll take rockbox are
> > > > capable of reading
> > > > files from 32 to 320KBPS, and with sample rates of 22 to 48KHZ.
> > > >
> > > > In short, the lower the bit rate and sample frequency, the
> > > > smaller the file,
> > > > but the poorer the playback quality.
> > > >
> > > > HTH,
> > > >
> > > > Rob
> > > >
> > > > -----Original Message-----
> > > > From: rockbox-bounces@cool.haxx.se
> > > > [mailto:rockbox-bounces@cool.haxx.se]On
> > > > Behalf Of Selamet Aydogdu
> > > > Sent: 01 February 2006 09:32
> > > > To: rockbox@cool.haxx.se
> > > > Subject: Question about CD-Quality and MP3
> > > >
> > > >
> > > > Hello,
> > > >
> > > > I search some sources that describe the different about MP3
> > > > and CD-Quality.
> > > > If it's possible that you can hear the same sound in MP3,
> > > > that exists too in
> > > > CD-Quality? Whats about OGG?
> > > >
> > > > Greetings
> > > > Selamet
> > > >
> > > >
> > > > --
> > > > No virus found in this incoming message.
> > > > Checked by AVG Free Edition.
> > > > Version: 7.1.375 / Virus Database: 267.14.25/247 - Release
> > > > Date: 31/01/2006
> > > >
> > > > --
> > > > No virus found in this outgoing message.
> > > > Checked by AVG Free Edition.
> > > > Version: 7.1.375 / Virus Database: 267.14.25/247 - Release
> > > > Date: 31/01/2006
> > > >
> > > >
Received on Fri Feb 3 04:21:37 2006


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