So there we are, the first audio players I've heard of that won't touch VBR <smile>.
On 27/12/2009, at 11:03 AM, Tim Noonan wrote: > Also, > > There are devices, even modern ones, which don't reliably, or indeed at all, > cope with VBR. > > The Olympus machines, even the DM-520 are a case in point - so use VBR with > care if you want to guarantee everyone and everything can play your MP3 > files. > > Regards > Tim > > Tim Noonan > Director, Vocal Branding Australia > Transforming products, brands and experiences so they Sound as great as they > look and feel! > > Phone: +61 419 779 669 > Web: www.vocalbranding.com.au/blog > Email: t...@vocalbranding.com.au > Twitter: www.twitter.com/VocalEssence > Skype: TimNoonan > > -----Original Message----- > From: pc-audio-boun...@pc-audio.org [mailto:pc-audio-boun...@pc-audio.org] > On Behalf Of Dane Trethowan > Sent: Sunday, December 27, 2009 9:05 AM > To: PC Audio Discussion List > Subject: Re: Pros and cons of varible bit rate > > Okay, I just consulted an audio engineer abut what you wrote about minimum > bit rates for VBR encoding and here's his response, it also talks about > setting VBR quality and I'll have a few words to say about this after his > quotation which follows: > >> Well, basically it depends on what you're trying to do. There are several > factors that contribute to VBR quality (apart from encoding quality settings > of course). Most immediately noticeable is the over-all VBR quality > setting, which `weights' the VBR result between the minimum and maximum you > set. Imagine VBR as a set of scales swinging everywhere between min. and > max. depending on what's going into the encode. VBR quality simply > determines how the scales are weighted, either more towards minimum or > maximum depending on what you set. The higher VBR Quality, the less the > encoder will `throw away', and so the more it will weight the encode towards > the higher end of the scale. If the quality is set high enough, you won't > achieve *anything* by increasing the minimum; all you'll do is make your > file larger for no benefit, since the encoder will waste a load of bandwidth > encoding things (such as silence or low frequencies) that don't need it. > Conversely, if your VBR Quality setting is too low, the encoder will throw > away so much that everything will get pushed towards the lower end, and so > the Minimum setting will make a great deal more difference. But even then, > all it will do is make your file bigger, and probably it won't help the > encode quality, since you shouldn't have set the quality so low in the first > place. >> >> So, basically, for normal operation, it's a complete waste of time pushing > up the minimum. The exception is if you have a hardware player that can't > cope with very low bitrates (our Omni DVD players were hopeless with > anything below 64KbPS), unless, _perhaps_ if the source is *very* noisy (an > old dodgy cassette) where you don't want noise causing a load of artifacts, > but you still want the file as small as possible. But under those > circumstances, you'd be far better off processing the original source and > removing as much noise as possible without damaging the audio _before_ > encoding. >> >> The only other reason you might want to push up the minimum is if the > encoder has a dodgy VBR algorithm that tends to push too much towards the > bottom of the scale, even when the VBR Quality setting is high. LAME's > `--vbr-old' algorithm is excellent, but `--vbr-New' still has problems. > Unfortunately, other encoders (such as Fraunhofer) are a *hell* of a lot > worse, so if you're forced to use them, it might be worth it. >> >> Anyway, hope this explains things; basically, unless you have a very > specific need, don't play with Min/Max bitrates - you're likely only to get > worse encodes and bigger files. > > Thank you kind Sir for your time and trouble <smile> so now to my additional > notation about VBR quality and this can add to confusion. When setting VBR > quality it works in the reverse as it looks, in other words the lower the > number the higher the VBR quality, 3 or 4 may be a good setting for music, > for mono audio or talking books, audio documentaries etc try say between 4 > and 6. > > On 27/12/2009, at 6:38 AM, Kevin Lloyd wrote: > >> The only point I'd add to Dane's notes is that I have read advice around > not setting your variable floor too low. I'd suggest for music that you set > the floor to 128kbps rather than the suggestion below of 16kbps. >> >> Regards. >> >> Kevin >> E-mail: kevin.llo...@sky.com >> ----- Original Message ----- From: "Dane Trethowan" > <grtd...@internode.on.net> >> To: "PC Audio Discussion List" <pc-audio@pc-audio.org> >> Sent: Saturday, December 26, 2009 7:33 PM >> Subject: Re: Pros and cons of varible bit rate >> >> >>> I suppose it comes down once again to personal preference, I've been > using varriable bit rates for youears. >>> >>> As I understand it, encoding with a varriable bit rate takes a lot longer > as the encoder looks at every sample of the song thus deciding what bit rate > it should be encoded at, silence for example is encoded at a lower bit rate > than a full sample of orchestra sound, minimum and maximum bit rates for > variable encoding are set up with your encoding engine such as LAME so for > the best and accurate results you're better off doing this sort of thing > manually with a command line so use an app which supports this, Exact Audio > Copy is an excellent choice here. >>> >>> Their are several methods of VBR encoding, "Old" and "new", "new" is > quicker for those jobs you want out the door fast but quality isn't quite as > good if you're picky, with today's flying processor speeds you may as well > use "Old". >>> >>> Also note that some older players may not handle VBR playback though I > haven't struck one that doesn't yet. >>> >>> Suggested minimum and maximum bit rates for VBR? Well just use the > minimum and maximum rates available or if you're configuring from a command > line or a piece of software that takes full advantage of the LAME-ENC.dll > library then 16 bits for the minimum and 320KBPS for the maximum, there are > 2 quality settings you have to be aware of here, one is VBR quality and you > may wish to change this for certain audio material you're encoding, say > music and talking books. The other quality setting leave at maximum, will > take longer but far better results. >>> >>> >>> On 27/12/2009, at 6:21 AM, Jamie Pauls wrote: >>> >>>> The subject is a question, not a statement. I have been uploading Main > Menu archives as a 128KBPS MP3 file. I see that many people recommend > 192KBPS, but there a parts of the show that really don't need that high a > bit rate. In fact, I have also read that encoding at too high a bit rate can > cause unwanted artifacts just as much as encoding at too low a bit rate. > Variable bit rate seems a good choice for me to use, but I would like some > thoughts from audio experts. Thanks. >>>> >>>> >>>> Jamie Pauls >>>> MSN: jamiepa...@hotmail.com >>>> Skype: jamie.pauls >>>> >>>> To unsubscribe from this list, send a blank email to: >>>> pc-audio-unsubscr...@pc-audio.org >>> >>> >>> ****************************** >>> >>> Dane Trethowan >>>> From Melton Victoria Australia >>> mailto:"grtd...@internode.on.net >>> Twitter: http://twitter.com/grtdane >>> blog: http://www.grtdane.wordpress.com >>> Phone United Kingdom >>> 02032874641 >>> Phone Australia >>> 0390058589 >>> Phone United States >>> 8159261869 >>> Fax: >>> +61 3 9743 7954x >>> MSN grtd...@dane-trethowan.net >>> skype:grtdane12 >>> >>> ****************************** >>> >>> >>> >>> >>> >>> To unsubscribe from this list, send a blank email to: >>> pc-audio-unsubscr...@pc-audio.org >> >> >> To unsubscribe from this list, send a blank email to: >> pc-audio-unsubscr...@pc-audio.org > > > ****************************** > > Dane Trethowan >> From Melton Victoria Australia > mailto:"grtd...@internode.on.net > Twitter: http://twitter.com/grtdane > blog: http://www.grtdane.wordpress.com > Phone United Kingdom > 02032874641 > Phone Australia > 0390058589 > Phone United States > 8159261869 > Fax: > +61 3 9743 7954x > MSN grtd...@dane-trethowan.net > skype:grtdane12 > > ****************************** > > > > > > To unsubscribe from this list, send a blank email to: > pc-audio-unsubscr...@pc-audio.org > > > To unsubscribe from this list, send a blank email to: > pc-audio-unsubscr...@pc-audio.org ****************************** Dane Trethowan >From Melton Victoria Australia mailto:"grtd...@internode.on.net Twitter: http://twitter.com/grtdane blog: http://www.grtdane.wordpress.com Phone United Kingdom 02032874641 Phone Australia 0390058589 Phone United States 8159261869 Fax: +61 3 9743 7954x MSN grtd...@dane-trethowan.net skype:grtdane12 ****************************** To unsubscribe from this list, send a blank email to: pc-audio-unsubscr...@pc-audio.org
