Audio Codecs

[isadissa]

Hi all.

Since the recent boxee updates, I decided to run a check of what audio codecs boxee plays

here goes..

All files were ripped directly using db poweramp

I am using a boxee box with the most recent firmware, connected to an Onkyo tx-sr608 with HDMI

MP3- Frauenhofer & Helix both fine with cbr & vbr
Mp2 - fine upto 320 kbs
Musepack - fine upto 320kbs
aac - fine upto 400 kbs cbr & vbr
apple lossless - fine upto 24bit 96khz
ape- fine
flac - fine
m4a - fine upto 400 kbs cbr & vbr
wav - fine but no tag reading
wma 9 - fine upto 320 cbr & vbr
wma 10 pro - fine upto 24 bit 96 khz
wma 10 pro upto 7.1 channels 24 bit 96 khz
ac3 - fine
ogg - upto 600 kbs
wavepack - lossy & lossless fine
shorten - fine but no tag reading


hope this of use to you all..

What are you guys using, out of interest !!

Regards

Isadissa

[Prospero424]

Great list! Out of curiosity: when you say it does "up to 400kbps" with AAC, is it that it doesn't play files with higher bitrates or just that you didn't test with higher bitrates? I ask because I have some 96Khz AAC files (stereo) that have true bitrates of around 500 and some 96Khz surround AACs with even higher bitrates (800-1200Kbps).

As for what I use: FLACs for albums I really care about, and AAC at ~300kbps VBR (.75 quality) using the Nero AAC encoder for albums I want to keep in online storage, but not permanently archive in a lossless format. I also use DBPowerAmp for encoding. Fantastic program.

I have a lot of respect for LAME (MP3 encoder), but I prefer AAC because, to my ears, it produces better quality for the file size. And the (free) Nero encoder still sounds much better than the open-source FAAC does to my ears.

Why do I use .75 quality (~300Kbps) Nero AAC? I did a prolonged listening test using Foobar's double-blind (DBX) testing plugin, playing to very nice Senheisser headphones connected to a Presonus Firebox (Firewire with vacuum tube preamp) over ASIO. The lossless sources I used were all 24-bit, 96Khz FLAC files. I was able to reliably pick which were the lossless (FLAC) files and which were the lossy (96Khz AAC) files at a statistically-significant rate (about 2/3-3/4 of the time) up until I got to .75 quality. At that level, I could no longer reliably discern which were lossless and which were lossy.

One of these days I might switch to Apple Lossless over FLAC because the files it produces tend to be slightly smaller, but probably not for another year or so. I'll just have to see how well it's supported across all platforms.

[isadissa]

Hi Prospero..

The AAC/M4a upto 400 kbs was as high as I went in the test...so no, it was not limited by the boxee itself..

I personally rip to Musepack for boxee playback and I archive with flac..

But I Can't give any great or wonderful reason as to why exactly, other than that it sounds better to me !!.

I always try to be careful, when it come to discussing audio codecs, as people do get somewhat polarised in their views as to what is better..
I think, for you, that using apple lossless in the future, will offer you no great advantage, unless you are an apple user !!, the space savings are minimal.

I suggest for fun that you rip a cd to windows media 10 , 5.1 24/96. the boxee will output it as 5.1 pcm and it is strangely interesting...

anyway have fun with music...

[Prospero424]

Ah, thanks for the info on AAC vis-a-vis Boxee!

Hehe, yeah, people tend to get religious about this stuff. No worries about that in my case, though. I just use what sounds best to me, and realize that what sounds good to me may not sound good to someone else with someone else's equipment.

Musepack produces fantastic quality for CD-quality audio; every bit as good as any other lossy format. But there are two reasons I don't personally use it:

1. I've had hardware and software compatibility issues with it in the past (not with Boxee, though!)

2. It's limited to a (I believe) 48khz sampling rate and has limited multichannel (surround) support. Most people don't give a crap about this stuff, though.

Yeah, I agree about Apple Lossless. The only way I'd ever switch is if every device/app that supported FLAC also supported Apple Lossless, which is going to take a good while to come about.

Windows Media Audio 10 Pro's ability to encode to 24/96 multichannel is nice, but I think the bitrates the encoder is capable of using (only up to 768Kbps) are too low for 96Khz 5.1 audio. 768Kbps is more than enough for even 96Khz stereo sources, but it's just not enough bitrate when you've got up to eight streams going, and the WMA Pro encoder treats 768 as the global max, even in VBR mode. It produces nice, small files, but the maximum quality the WMA Pro 10 encoder is capable of producing for 96Khz 5.1 encodes is roughly equivalent to a .45-quality VBR Nero AAC encode.

I wasn't aware that the WMA 10 Pro encoder automatically upmixed a stereo source to 5.1 audio when told to do a 5.1 encode. Nifty! I just assumed it would leave the surround channels unpopulated or just duplicate the side channels, but it actually does seem to do proper upmixing. I'm not a fan of upmixing in general, and I think DSPs do a better job of it anyway, but having the option there is pretty cool.

WMA's big problem is and always will be cross-platform compatibility. Yeah, there are "appropriated" third-party encoders/decoders for Posix-based systems out there, but they have their own sets of associated problems and quality can vary greatly. It's kind of a mess. And that's before DRM even comes into the picture.

Anyway, always nice to have a conversation on this topic. Cheers!

[isadissa]

Hi,

With the wma pro, i was just tinkering about to be honest, and whammy my onkyo set to direct without filters was banging out 5.1 channels, quality not too good, effects sometimes strange but still interesting..

I have never really thought too much about 24/96 archiving as my cd's are all 16/44.1 and am I going to get anything out of it other than large files..and of course boxee only sends a 16 bit 48khz downmixed signal over hdmi anyway !

I am about to start ripping my cd collection to my hard drive so am still trying to work out which would be the best...with lossless I am going to need around 4-5 Tbytes of harddrives....so lossy would be logical, but sound quality imperative...

Will have to make a decision soon.

5.1 processing would be great but other than dbpoweramp wma 10 encoder it seems to a lot of work...

any thoughts ?

see ya later

[isadissa]

Hi,

With the wma pro, i was just tinkering about to be honest, and whammy my onkyo set to direct without filters was banging out 5.1 channels, quality not too good, effects sometimes strange but still interesting..

I have never really thought too much about 24/96 archiving as my cd's are all 16/44.1 and am I going to get anything out of it other than large files..and of course boxee only sends a 16 bit 48khz downmixed signal over hdmi anyway !

I am about to start ripping my cd collection to my hard drive so am still trying to work out which would be the best...with lossless I am going to need around 4-5 Tbytes of harddrives....so lossy would be logical, but sound quality imperative...

Will have to make a decision soon.

5.1 processing would be great but other than dbpoweramp wma 10 encoder it seems to a lot of work...

any thoughts ?

see ya later

[Prospero424]

Yeah, I've got a lot of HD audio (DVD-Audio and SACD) rips collected. That's the only thing I use 24/96 FLACs and sometimes 96Khz AACs for. No point with CDs. Some of the 24/96 FLAC albums for these rips can be upwards of 3.5-4GB! Those are the ones I sometimes compress to 96Khz AAC, which results in about 450MB per album. Much more manageable.

As for your impending CD backup project: lossy's great for storage space, but you better make sure you NEVER want to transcode them to another format in the future. As I'm sure you know: you can't get the lost quality back, and encoding it again will just lose more detail.

I'd suggest doing what I did: use Foobar's DBX (double-blind test) plugin using your very best audio device and your very best headphones/speakers and test different lossy formats, bitrates and settings to see what sounds "transparent" to you. It's a pain, but it's a hell of a lot easier than re-ripping your entire CD collection if you change you mind down the road!

But if you have the space, might as well stick with FLAC. Hell, you can get a 2TB hard drive for like $75 now!

Oh, and I'd suggest avoiding 5.1 upmixing when encoding. It's always better to do that with a DSP output plugin for your music player or on the receiver using something like Dolby Pro-Logic II.