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Rockbox mail archiveSubject: Re: AW: Question about CD-Quality and MP3Re: AW: Question about CD-Quality and MP3
From: Bluechip <csbluechip_at_gmail.com>
Date: Fri, 03 Feb 2006 04:04:21 +0000 At 03:18 03/02/2006, you wrote: >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? There is nothing identifying on the plugs or carry case ...and any other packaging is long gone ..I've had these things for *YEARS* ...a quick look at the web page suggests http://www.etymotic.com/ephp/er20.aspx as being the closest I can find. I was sure they came in several dB attenuation values, but they only seem to be 20 now. Plus the ones I have have CLEAR bass attenuation fittings, the ones in the picture have RED fittings. "Contents may differ from illustration"?? BTW. on a more serious note, the site quotes $12 per pair ..even the pop-open carry case has lasted me as long as the plugs, and I expected THAT top fall apart in no time, but the plastic just never hardened or split! Go figure!? Hope that helps, BC >rocker > >----- Original Message ----- >From: "Bluechip" <csbluechip_at_gmail.com> >To: "Rockbox" <rockbox_at_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_at_gmail.com> > >To: "Rockbox" <rockbox_at_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_at_gmail.com> > > >To: "Rockbox" <rockbox_at_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_at_cool.haxx.se > > > > > [mailto:rockbox-bounces_at_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_at_cool.haxx.se > > > > > [mailto:rockbox-bounces_at_cool.haxx.se]On > > > > > Behalf Of Selamet Aydogdu > > > > > Sent: 01 February 2006 09:32 > > > > > To: rockbox_at_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 2006-02-03 Page template was last modified "Tue Sep 7 00:00:02 2021" The Rockbox Crew -- Privacy Policy |