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mwphoto
2005-05-30, 02:56
First this will be a cross-post to the audiophile and beginners forum, I apologise if that breaks some rules here.

I have just drafted a WikiPage on how to get the best audio quality from the SquuezeBox. It's whay I wanted to read a few days ago when I got my new toy. It's at http://wiki.slimdevices.com/index.cgi?HowtoBestAudioQuality if you want to take a look.

I wanted something that provides basic information for a non-technical user (I'm assuming someone that knows about hifi, but not about computers, like my dad). I hope that people that know more about this will feel free to add edit and contribute to the page as long as they remember its focus is to provide information for users new to the community. In particular if you disagree with what's there can I request that you post a reply to the forums and not change it directly.

Finally, I've assumed that in the tradition of wiki's even newbies like me can write pages without asking permission first. If I've stepped on any toes, I apologise, get in touch and I'm sure we can work something out.

Malcolm

William
2005-05-30, 11:24
You should edit to include Apple Lossless and iTunes also. ;)

mwphoto
2005-05-30, 14:40
Thanks for the comment,

I know nothing about these 2 formats - would you like to make the edits?

If not can you let me know if iTunes format is Lossless?

Thanks

Malcolm

> -----Original Message-----
> From: audiophiles-bounces (AT) lists (DOT) slimdevices.com
> [mailto:audiophiles-bounces (AT) lists (DOT) slimdevices.com]On Behalf Of William
> Sent: 30 May 2005 19:24
> To: audiophiles (AT) lists (DOT) slimdevices.com
> Subject: [SlimDevices: Audiophiles] Re: New HowTo on Audio Quality
>
>
>
> You should edit to include Apple Lossless and iTunes also. ;)
>
>
> --
> William
>

Fabrice Rossi
2005-05-31, 01:14
Hi.

Nice page.

You might want to add a recommandation for cdparanoia
(http://www.xiph.org/paranoia/) for linux users (as far as I understand,
it uses the same tricks as EAC). A nice front end for this tool on linux
is grip (http://nostatic.org/grip/). It allows to rip to flac.

You might also point out that FLAC is an open format and will therefore
stay forewer. This is not the case of both apple lossless and wma lossless.

Fabrice

street_samurai
2005-06-01, 16:09
Hi,

Good idea about the wiki page. I won't edit your page but I will point out a few things:


EAC and cdparanoia have been written to get the best chance of getting a perfect copy of the audio data on your CD (use EAC in secure mode)
I haven't used cdparanoia but EAC at least is not setup -by default- to get a perfect copy of your audio. Secure mode is just the start of the perfect rip. Perhaps link to a guide like: http://www.hydrogenaudio.org/forums/index.php?showtopic=30959


There are good arguments for using MP3 but those arguments aren't based on sound quality.
I'd be extremely careful making broad statements like this. The average pair of ears (and many audiophiles) -can not- tell the difference between a properly encoded, high bit-rate MP3 (using a good encoder) and a lossless source.


Use the digital outputs on your SB2 and feed them into your DAC
I disagree here also. Lots of low and mid-range A/V amps have crappy DACs in them (as well as lots of sound cards etc.). My suggestion here would be to use the Squeezebox 2's DAC unless you are sure you have a better external DAC.

Plus, this almost implies that the user needs to go out and get an external DAC when the built-in DAC of the SB2 is -amazingly- good. (especially for the price).


You should turn of the volume control that is present in the SB2 and only use the volume control on your HiFi.
I think you should point out here that this is only relevent if you are using the digital output of your SB2. For analog this setting makes no difference however as long as you are outputing to something with a preamp in it, then the volume should be set to maximum even for analog.

Just my thoughts,

ss.

p.s. iTunes uses the lossy AAC format

mwphoto
2005-06-01, 16:47
Hi Ss,

Thanks for your comments,

the link to using EAC in the best mode is good - I'll include it.

Not so sure about the MP3 comment, although I do accept the wording of what
I have could be improved. My point here I suppose is that there are some
people that can tell the difference (if they have enough good hardware).
Would you agree that MP3 files can be no better than a lossless file? That's
the message. I agree that in the right conditions it may not be possible to
tell the difference. While my initial statement is a bit harsh (and I'll
tone it down) I still think it's right. If we're trying to write a wiki to
get the best audio I wouldn't want to recommend using MP3.

On the DAC point I agree, I've never owned an AV amp, all my kit has been
external DACs to provide 2 channel audio for a straightforward (albeit high
end) stereo system so I didn't think about the AV amp option. I hoped my
comment about the quality of the DAC would cover it. Perhaps it needs
reinforcement. As a separate thought if cheap AV amps are that bad will the
amp stage themselves be any good? I guess not - but it's probably not worth
dwelling on.

I certainly never intended to imply the SB2 needs an external DAC. I wanted
to emphasise that it could take one though, and if you already have one you
should consider using it. I'll see if the wording could change to make this
clear.

Thanks for the comment on the digital volume control, I didn't know this so
I'll update accordingly.

However, it's late where I am so I'll apply those changes tomorrow when I
have a clear head.

Many thanks for your input.

Malcolm
> -----Original Message-----
> From: audiophiles-bounces (AT) lists (DOT) slimdevices.com
> [mailto:audiophiles-bounces (AT) lists (DOT) slimdevices.com]On Behalf Of
> street_samurai
> Sent: 02 June 2005 00:10
> To: audiophiles (AT) lists (DOT) slimdevices.com
> Subject: [SlimDevices: Audiophiles] Re: New HowTo on Audio Quality
>
>
>
> Hi,
>
> Good idea about the wiki page. I won't edit your page but I will point
> out a few things:
>
> > EAC and cdparanoia have been written to get the best chance of getting a
> > perfect copy of the audio data on your CD (use EAC in secure mode)
> I haven't used cdparanoia but EAC at least is not setup -by default- to
> get a perfect copy of your audio. Secure mode is just the start of the
> perfect rip. Perhaps link to a guide like:
> http://www.hydrogenaudio.org/forums/index.php?showtopic=30959
>
> > There are good arguments for using MP3 but those arguments aren't based
> > on sound quality.
> I'd be extremely careful making broad statements like this. The average
> pair of ears (and many audiophiles) -can not- tell the difference
> between a properly encoded, high bit-rate MP3 (using a good encoder)
> and a lossless source.
>
> > Use the digital outputs on your SB2 and feed them into your DAC
> I disagree here also. Lots of low and mid-range A/V amps have crappy
> DACs in them (as well as lots of sound cards etc.). My suggestion here
> would be to use the Squeezebox 2's DAC unless you are sure you have a
> better external DAC.
>
> Plus, this almost implies that the user needs to go out and get an
> external DAC when the built-in DAC of the SB2 is -amazingly- good.
> (especially for the price).
>
> > You should turn of the volume control that is present in the SB2 and
> > only use the volume control on your HiFi.
> I think you should point out here that this is only relevent if you are
> using the digital output of your SB2. For analog this setting makes no
> difference however as long as you are outputing to something with a
> preamp in it, then the volume should be set to maximum even for analog.
>
>
> Just my thoughts,
>
> ss.
>
>
> --
> street_samurai
>

street_samurai
2005-06-01, 18:04
Hi Malcolm,

I agree with you completely on all your points. And yes, I agree than an MP3 can never be better than the lossless source. Although I think you'd be shocked at how many people can not tell the difference if the MP3 is ripped correctly (I know I was when I did an ABX test of WAV vs. lame MP3 insane). MP3 has come a long way since its 64 or 128kb CBR beginnings.

Don't get me wrong, I -still- ripped my entire collection to FLAC but not necessarily for sound quality purposes but to ensure that I have a perfect archive of my music for the future... and just in case I buy a really nice stereo in the future on which I -can- tell the difference :).

I think it probably depends on the model for AV stuff. Some (especially older stuff) focused more on the amp than the digital because digital was not as prevalent. Even a great DAC from a few years ago may be out-shined by the Burr-Brown in the SB2. I just wanted to make sure that people weren't plugging their SB2s into whatever they had with a DAC on it thinking they would get better sound.

Again nice work with the wiki, I think its a great idea.

ss.

pfarrell
2005-06-01, 18:43
On Wed, 2005-06-01 at 18:04 -0700, street_samurai wrote:

> I think it probably depends on the model for AV stuff. Some (especially
> older stuff) focused more on the amp than the digital because digital
> was not as prevalent.

Depends on your timeframe. DVDs with Dolby Digital (5.1) came out
last century, along with $300 receivers with five channels of 80 or so
watts.

For movies, the sound quality requirements are not that high.
You make the explosions loud and put the flyover sound starting
in the rear and pan it forward and the human ear recognizes it.
Kinda like how we recognize human voices over a radically
bandwidth challenged telephone.

To recreate high quality stereo in a room is much, much harder.

It would probably be a lot easier if audiophiles accepted multi-channel,
but I don't think it will happen. I know my decorating committee
is not ever gonna allow more serious speakers in the living room.

It there was a multi-channel audio standard, with the rears restricted
to ambiance only, then it would be a lot easier to see it
happening.

Of course most of the kids, including mine, don't care at all
about sound quality.

--
Pat
http://www.pfarrell.com/music/slimserver/slimsoftware.html

GregD
2005-06-02, 01:28
p.s. iTunes uses the lossy AAC format

Depends on your options - but if you choose Apple Lossless than it doesn't use AAC!

GregD
2005-06-02, 01:37
I think you should point out here that this is only relevent if you are using the digital output of your SB2. For analog this setting makes no difference however as long as you are outputing to something with a preamp in it, then the volume should be set to maximum even for analog.


I think Sean explained what the SB2 and SB1 do here. On SB1 there is an analogue volume control - and so there is no loss of digital bits in using the volumne control. On the SB2 the volume control on the analogue outputs uses the digital volume reduction. SB2 is 24 bit - so you can do quite a bit without losing data - but untimately this will truncate bits.

So for the reasons you outline - plus the possibility of bit loss it probably makes sense for an audiopjile to keep the volume at max. Not worth worrying too much if you can't though.

William
2005-06-02, 06:12
...
p.s. iTunes uses the lossy AAC format

iTunes actually has 3 lossless codecs to choose from: WAV, AIFF, and Apple Lossless.

street_samurai
2005-06-02, 12:29
iTunes actually has 3 lossless codecs to choose from: WAV, AIFF, and Apple Lossless.

Not to get completely off topic here, although I've never bought any music from iTunes I -think- that we are confusing ourselves here. My statement was noting that you can only buy lossless AAC files from iTunes (although I should have clafied it better). What I think you are saying is that iTunes can create WAV, AIFF and Apple Lossless files from other sources. Correct?

ss.

Dan Sully
2005-06-02, 16:14
* William shaped the electrons to say...

>The iTunes Music Store sells ACC lossy music. However there is no where
>I'm aware of that you can legally download lossless music that is 100%
>legitimate. So yes the iTunes Music Store just like all other legal
>download stores offers only lossy music.

http://www.magnatune.com/ sells FLAC.

-D
--
On a long enough timeline, the survival rate for everyone drops to zero.

William
2005-06-02, 16:18
... I -think- that we are confusing ourselves here. My statement was noting that you can only buy lossless AAC files from iTunes (although I should have clafied it better). What I think you are saying is that iTunes can create WAV, AIFF and Apple Lossless files from other sources. Correct?

ss.

I'm not confused but you are confusing the iTunes Music Store with the iTunes software program. Two completely (though related) things.

The iTunes Music Store sells ACC lossy music. However there is no where I'm aware of that you can legally download lossless music that is 100% legitimate. So yes the iTunes Music Store just like all other legal download stores offers only lossy music.

iTunes (the software program) can rip your CDs (the only way to obtain lossless music) in 3 deferent lossless formats. I use iTunes and have about 350GB (almost 15,000 songs) and all but about 20 songs are ripped using Apple Lossless from my CD's which reduces the storage data by about 50%. I only get the 1 free song a week from the iTunes Music Store so these are all I have that are lossy.

street_samurai
2005-06-02, 16:36
I'm not confused but you are confusing the iTunes Music Store with the iTunes software program. Two completely (though related) things.
Sigh. Sometimes I can't help wondering if people respond to things on these forums just make themselves feel smart.

Yes, you are techncially correct. There are two different semantic ideas: music store and iTunes. However, I would guess that 99% of people would consider them the same thing because there is no way to use the music store without iTunes... and no they are not "completely different". If you could buy tracks outside of iTunes then you might be able to think of them as different.

I think my post was pretty clear without getting into silly semantics.

ss.

William
2005-06-02, 17:25
...http://www.magnatune.com/ sells FLAC.
...
I stand corrected and should amend (not edit) my post to say mainstream label music (like Warner or Sony). ;)

street_samurai
2005-06-03, 14:15
Breaking news is that MusicGiants will soon start selling lossless tracks from major labels:

http://www.musicgiants.com/

An extremely poorly written business week article covers some of the details... although its so absolutely wrong on the technical side of things, its hard to believe the business side:

http://www.businessweek.com/technology/content/jun2005/tc2005062_3663_tc024.htm

ss.