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weinstro
2010-12-29, 10:15
Hi,

My current setup is this:
- SB3 connected via LAN
- Boom connected via WiFi
- Laptop running SBS, with media stored on a NAS, configured as a file server / disk backup
- Music is managed via iTunes, with media stored as AIFF

This generally works well, but it severely limits how much I can store on my iPhone, and I'm increasingly concerned with bandwidth consumption, especially over WiFi.

What do I give up by going to ALAC as a file format? Is it worthwhile to have two libraries, one in ALAC, and the other in FLAC? My big concern here would be ease of use for other users (kids, wife, etc.).

Regards,

rob

Mnyb
2010-12-29, 10:40
You wont give up a thing both ALAC and FLAC has very good tagging abilities and can have embedded artwork .

All lossles formats sound the same btw (they are lossles as the name cleverly implies ;) ) so you wont give up anything .

If you must use iTunes and iThings to play files then ALAC is the real option for you .

What Squeezeboxserver does then is transcode alac to flac on the fly this will up your CPU load while playing depending on the spec of the laptop you may notice (or not) .

You may already do this aiff is probably transcoded to flac to minimise badwith use over wifi (depending on settings in sbs)

FLAC is a free non-proprietary format supported by more platforms than ALAC .
And you SB3 can play this directly .

Another way if want two libraries is a lossy one mp3 or AAC for the portables and iTunes, and a FLAC library for SB3 and Squeezeboxserver (and don't use iTunes integration at all ) .

garym
2010-12-29, 12:00
Another way if want two libraries is a lossy one mp3 or AAC for the portables and iTunes, and a FLAC library for SB3 and Squeezeboxserver (and don't use iTunes integration at all ) .

+1. This is what I do (FLAC library plus mp3/aac of files for which I don't have FLAC for Squeezebox players, and an mp3/aac version of everything for use in itunes to feed iphones/ipods). And I do NOT use itunes integration.

kidstypike
2010-12-29, 12:12
+1. This is what I do (FLAC library plus mp3/aac of files for which I don't have FLAC for Squeezebox players, and an mp3/aac version of everything for use in itunes to feed iphones/ipods). And I do NOT use itunes integration.

+1. Exactly the same for me. (And I do NOT use itunes integration).

weinstro
2010-12-29, 16:51
You wont give up a thing both ALAC and FLAC has very good tagging abilities and can have embedded artwork .

All lossles formats sound the same btw (they are lossles as the name cleverly implies ;) ) so you wont give up anything.

A while ago, I did A/B testing (but not ABX testing) between ALAC and AIFF, and I could not hear a difference.


What Squeezeboxserver does then is transcode alac to flac on the fly this will up your CPU load while playing depending on the spec of the laptop you may notice (or not) .

You may already do this aiff is probably transcoded to flac to minimise badwith use over wifi (depending on settings in sbs).

Which may be why I couldn't hear a difference. I thought SB3's could decode AIFF files natively. Could you please direct to where/how to adjust the file type decoding settings to force this, verses transcoding at the server? I'd like to do some comparisons between AIFF > AIFF; AIFF > FLAC; ALAC > FLAC.

It took time to figure it out, but I like the iTunes integration, and I'm not in a hurry to have duplicate libraries unless there's a compelling reason to do so.

Many thanks!

Mnyb
2010-12-30, 00:28
A while ago, I did A/B testing (but not ABX testing) between ALAC and AIFF, and I could not hear a difference.



Which may be why I couldn't hear a difference. I thought SB3's could decode AIFF files natively. Could you please direct to where/how to adjust the file type decoding settings to force this, verses transcoding at the server? I'd like to do some comparisons between AIFF > AIFF; AIFF > FLAC; ALAC > FLAC.

It took time to figure it out, but I like the iTunes integration, and I'm not in a hurry to have duplicate libraries unless there's a compelling reason to do so.

Many thanks!

SB3 decode "PCM" natively so WAV and aiff can be sent as PCM .

But that is a completely pointless and futile exercise as all lossles formats sound the same. This is an old debate on this forum (se ourt audiophile section) and others .
It can be proved that for all lossles formats the digital output on the squeezebox is identical (bit perfect) so there is no electrical or mathematical difference in the output signal. Other members have measured and compared the analog outs with audiodiffmaker and found them virtually identical, down to players noise floor and the residue is random noise.

You don't really need to hassle trough this yourself doing level matched abx tests (all other test will make you victim to some bias and wont prove anything) When it can be proven by other means.

Also FLAC has support for replaygain tags and I suppose ALAC has for iTunes soundcheck, this is function to level out volume difference between tracks and albums this does not alter the files but it tells the squeezebox to use offsets in the volume by for example -10dB (typical modern recording ) .

This is a player setting "Volume Adjustment/Replay Gain" turn it off if going to compare wav flac side by side .

However in settings > advanced > file types you find what your are looking for .


Beware that changing these settings can brake usefull trancoding behaviors like making 24/96 files playable on an SB3 that only does 24/48 .

Or simply use ALAC or FLAC, further flac is proven to be lossles countless times by third parties. Also you can do that every time you encode such file, FLAC has a compare function where it decode and compare to the input file on the fly to make sure it's identical, it is the verify option.

Btw lossles audio is very different compared to mp3 or AAC it is better to compare it with winzip that compress documents for on the computer it does not lose data and the process can be reversed.

weinstro
2011-01-03, 12:29
Hi, thank you for your prior responses. I have a followup question...


...What Squeezeboxserver does then is transcode alac to flac on the fly this will up your CPU load while playing depending on the spec of the laptop you may notice (or not).

How much of a CPU load is this? Right now, if the laptop running SBS is running a virus scan, lots of websurfing, or other activities, the music stream does get interrupted. However, I cant tell if this is from processor overload or network bandwidth limitations.

Right now, there are two SB's. I'd like to add 2 more. If the file format is mostly ALAC, implying server side transcoding, will this be an issue?

I have a desktop tower that I repaired with an Athlon 64, running at 3.7 GHz with 2 GB RAM. Would this be a better (sufficient) choice?

Thanks!

Mnyb
2011-01-03, 12:52
Your laptop is it an windows machine look in the task manage while it's happening.

If it is a linux or Mac use "top" in a Terminal window

Hard to tell whats whats re transcoding I'm using a tiny 1,2GHZ via-epia mini-itx probably slower than your laptop it does not struggle much with this.
But as it is my sbs server it does not do anything else .

Having another machine running the servers sure speeds things up :-)

weinstro
2011-01-03, 15:20
Your laptop is it an windows machine look in the task manage while it's happening.

If it is a linux or Mac use "top" in a Terminal window

Hard to tell whats whats re transcoding I'm using a tiny 1,2GHZ via-epia mini-itx probably slower than your laptop it does not struggle much with this.
But as it is my sbs server it does not do anything else .

Having another machine running the servers sure speeds things up :-)

Windows machine. Point noted - I would have expected that SBS would be a fairly light processing load, but this machine is no longer a clean install. The desktop proposal above would be clean, dedicated, and unattractive to use (no keyboard, mouse; just remote connection).

Thanks!

Mnyb
2011-01-03, 15:32
You can search this forum in vain over the Question how powerful must my server be the answer is "it depends" and then everything turns into 20 questions :-)

You know when it not enough but not when it's enough .

virgiliomi
2011-01-03, 19:55
And it does all depend.

It depends on what format your music is currently in, and what formats your devices are capable of playing natively (as if the device doesn't support the format natively, it will need to be transcoded in realtime to another format).

It depends on what, how many, and what models of playback devices you have.

It depends on how many of those devices will be playing simultaneously, and what they will be playing (will they all be playing different music that needs to be transcoded? Will one be playing an internet radio stream, while another plays local music only?).

There are tons of variables that need to be taken into account... some have minor impacts, some have major ones.

Mnyb
2011-01-04, 00:27
OS, sbs version , how many users shall use the web-Ui at the same time.
How many and wich plugins some are CPU intensive.

weinstro
2011-01-04, 17:23
And it does all depend.

It depends on what format your music is currently in, and what formats your devices are capable of playing natively (as if the device doesn't support the format natively, it will need to be transcoded in realtime to another format).

It depends on what, how many, and what models of playback devices you have.

It depends on how many of those devices will be playing simultaneously, and what they will be playing (will they all be playing different music that needs to be transcoded? Will one be playing an internet radio stream, while another plays local music only?).

There are tons of variables that need to be taken into account... some have minor impacts, some have major ones.


OS, sbs version , how many users shall use the web-Ui at the same time.
How many and wich plugins some are CPU intensive.

I can quantify all of these points.

Worst case, I figure 4 devices (SB3, Boom, 2 Touches), playing ALAC, potentially simultaneously and independently. I'll assume that all of these devices will require transcoding at the server. All will be connected via LAN.

Desktop machine would be based on Windows XP, running latest generally available version of SB Server -- 7.5.2, IIRC.

Desktop machine would be dedicated to media streaming only -- no other gaming, web surfing, etc. iTunes would also be on this box, as would virus scanning software. No plans for MS Office, etc.

I use the podcast and pandora plugins. I'm intrigued by the DRC / Inguz plugins, but I'm not far enough on the learning curve for those, yet.

Should work OK, right?

Thanks!