BeoSound 5 Forum

Re: iTUNES PLUS SOUNDS POOR ON BEOSOUND 5...

Electrified — Wed, 02 Dec 2009 11:01:21 GMT

dkresz:

puncher:

If both 1. & 2. are lossless conversions, to what do you attribute the apparent superioity of the wma lossless file?

Primarily, on a blind test - comparing the same song at the same (lossless) resolution on the BM5. I encourage you to do the same.

Now to the speculative part: one is (mainly) Mac and the other is Windows? The codecs have diiferent encryption / decryption algorithms that are affected by the platform? BM5, being Windows XP Embedded, may be fine-tuned for WMA and WAV playback ? It will be interesting to re-run the same comparison test when the BM5 / BS5 software gets upgraded to officially support AAC lossless...

I have to toss my foot in here.

All that (and the rest of your posts on this subject) is emphatically wrong.

If in doubt, find an uncompressed track, say, a wave-format file. Md5 checksum it.

Convert the file to Aiff and then back to wave. Md5 checksum it.

Convert the file to ALAC (Apple Lossless) and then back to wave . Md5 Checksum it.

Convert the file to flac and then back to wave. Md5 checksum it.

Convert the file to WMA lossless and then back to wave. Md5 checksum it.

You will find that they ALL have the exact same checksum. The reason for this is, naturally, that they ALL are lossless containers, containing the exact same PCM-data.

As I said in the other thread: Any difference you hear is imaginary.

Re: iTUNES PLUS SOUNDS POOR ON BEOSOUND 5...

Puncher — Wed, 24 Jun 2009 18:06:53 GMT

dkresz:

Stan:

Because he wants to, and this proves nothing other than some people have a lot of money to spend.

I believe you've inadvertently offended half the B&O community How about: because they aspire to the best quality...

I don't believe he has - price, quality and functionality are not necessarily related as some recent products have highlighted.

Re: iTUNES PLUS SOUNDS POOR ON BEOSOUND 5...

dkresz — Wed, 24 Jun 2009 17:47:17 GMT

Stan:

Because he wants to, and this proves nothing other than some people have a lot of money to spend.

I believe you've inadvertently offended half the B&O community How about: because they aspire to the best quality...

As a side note, I have listened to a sound system with a separate master clock unit and there is a quite noticeable improvement.

Good morning for me (down-under).

Re: iTUNES PLUS SOUNDS POOR ON BEOSOUND 5...

Stan — Wed, 24 Jun 2009 17:09:47 GMT

"Why would audiophiles, even for CD playback, pay $20,000 for a separate master clock unit?"

Because he wants to, and this proves nothing other than some people have a lot of money to spend.

I'm done, too.

Goodnight/Good Morning/Good Afternoon (depending on where you live).

Stan

Re: iTUNES PLUS SOUNDS POOR ON BEOSOUND 5...

Puncher — Wed, 24 Jun 2009 16:13:58 GMT

I've run out of juice too!

I believe and will leave it at that - as in all of these "audiophile" cases, there can be no end to the debate, the believers cannot offer enough proof to convince those that don't - the ABX double blind test format cannot prove a null result, only that there is a statistically significant difference................... those that believe there is a difference tend to disagree with the double blind ABX test format -

it has always been thus!

Goodnight

Re: iTUNES PLUS SOUNDS POOR ON BEOSOUND 5...

dkresz — Wed, 24 Jun 2009 15:29:26 GMT

Stan:

First, I think you have a typo... "The transport process is definitely lossless (unless it uses network-based protocols... )". I'm pretty sure that you mean "lossy" (the opposite of lossless) since the rest or your statement talks about the effects of losing data (lower resolution, color degradation, etc.).

Yes, good pick-up (someone's paying some attention to these threads).

Stan:

Secondly, I agree with most of your facts, just not all of your conclusion. To paraphrase (and please correct me if I'm misinterpreting your words), your point is that because AV is "real-time", you can lose data because the algorithms/transport run out of time or buffer space to do appropriate error correction. This may be true with high resolution video such as Blu-Ray as rather intensive processing is required, and perhaps this is why you changed the subject more toward video.

Pretty much. And yes, the issue (bit error rate) is more evident as the data transfer rates increase for AV-based signals (Blu-ray, SACD, DVD-Audio etc)... I have no doubt, however, that CDs (PCM that is) faces this problem also (especially for a low-end computer -such as the BM5). Not so much due to the bandwidth aspect of the "transport" but for all the other factors in between (e.g. poor cabling leading to interference or inferior socket-based contact, master clock of the DAC). Why would audiophiles, even for CD playback, pay $20,000 for a separate master clock unit? "The master clock controls the accuracy of the sample frequency in a DAC. While audio interfaces do have an on-board clock, often these clocks either are not as stable as most of us would like, or they don’t have sufficient distribution."

I'm running out of juice on this one but, as I have stated, I encourage you all to do your own tests (being skeptical is not a bad thing, being wrong is a different matter )

Re: iTUNES PLUS SOUNDS POOR ON BEOSOUND 5...

Stan — Wed, 24 Jun 2009 09:10:48 GMT

I don't think we're beating a dead horse quite yet so I'm going to respond.

First, I think you have a typo... "The transport process is definitely lossless (unless it uses network-based protocols... )". I'm pretty sure that you mean "lossy" (the opposite of lossless) since the rest or your statement talks about the effects of losing data (lower resolution, color degradation, etc.).

Secondly, I agree with most of your facts, just not all of your conclusion. To paraphrase (and please correct me if I'm misinterpreting your words), your point is that because AV is "real-time", you can lose data because the algorithms/transport run out of time or buffer space to do appropriate error correction. This may be true with high resolution video such as Blu-Ray as rather intensive processing is required, and perhaps this is why you changed the subject more toward video.

However, I disagree that these factors have any impact on audio (at least the 2 channel CD resolution audio within a self contained system like the BS5) because, with today's hardware, the processing and data volume required for audio decoding is miniscule. For example, my 1.42GHz PPC MacMini can convert a 4 minute audio ALC to AIFF in ~15 secs. Only a very poorly designed system could not handle 15 secs of processing spread across 4 minutes of audio playback. Even though this is "real-time", as you can see, there is plenty of time to drain buffers, deal with codec latencies, do error correction... and this is far from a state of the art computer... it was criticized as "slow" even when it was brand new . Yes, codecs can have different latencies, but, for CD audio, they're all well within the hardware's tolerance.

Stan

Re: iTUNES PLUS SOUNDS POOR ON BEOSOUND 5...

dkresz — Wed, 24 Jun 2009 04:25:08 GMT

I promised to myself I won’t get drawn into this type of argument but here it is Audio or video information is transfered to a digital media at a certain resolution and speed (bit rate per second and sampling rate). This concept applies to time domain based signals, mostly those intended to be received in real-time by a consumer (such as voice-over IP or digital mobile phones). A ZIP file opened on a computer does not fit in this category 1. because it is not a time-based source of data and 2. because it can be error-checked and error-checked and error-checked as long as it takes for the hourglass on the computer to disappear (we should all be accustom to this scenario as long as you have used a computer before). The other misconception around digital data transfer being lossless is prompted by the internet. Most people think if you send a file from A to B (such as an email) it will be received by the recipient as it was intended by the source (hence, a perfect transfer). That assumption actually proves to be correct. There are a series of network protocols those computer geeks invented (such as TCP/IP) which prevent the data from being lost or degraded. That concept could even be extended to wireless protocols (such as data transfer between two Airport Express routers). But, back to the key point, in these scenarios data does not have to be transfered in real-time! You wait for it, it gets re-sent now and then, it gets buffered and sometimes it even disappears in the “cloud” of hardware and software that exists between the two parties in concern. In the AV world the concept of buffering (due to size limits and time-boxing) faces constraints for real-time data reproduction and it is also affected by the different OSs (Windows, Mac, Linux etc) as adopted by different brands of digital sources. B&O happens to use Windows XP Embedded for their media player dubbed BS5. Lossless is lossless at the source, that is, the disk in your hand, the piece of data stored on your hard-drive (FLAC, WMA or AAC whatever it may be). Once it leaves the media it goes through a process of: decoding for playback (different codecs, despite the fact of being both lossless, have different latency between source encoding and playback and can achieve the status of lossless at different bit rates BTW, which may have an impact on buffering?), transfer via well insulated high conductivity cables or lower quality cables (subject to one’s setup), conversion from digital to analogue (via a low quality or high quality DAC), and so forth. Over-buffering or interference results in bit / packet data drops (to ensure the signal is still presented in real-time). That results ina lower resolution output, or color degradation, or contrast loss etc. The transport process is definitively lossless (unless it uses network-based protocols and the buffer is large enough for the streamed data signal)!

Hence my earlier point: you could experience a better system throughput with lower resolution media files than you could experience with higher resolution files (as some have pointed out in this thread unless the perception factor plays an additional role which certainly clouds the entire argument). Hence the preference of AAC 256 Kbps over a full resolution CD / WAV. It depends on the weakest link in your system. If the system is capable to consume the full resolution signal in real-time there is no doubt the output will be superior to the lower resolution source. But that is not that easy to achieve and many home theatre setups out there have not reached that ideal capability. Hence the reservation of B&O going Full HD / Blu-ray too early (despite all the marketing hype stating you can do that with little money). The technology is not mature enough to support that "lossless" type of playback unless you pay the big bucks to upgrade or improve it. Two source files being lossless (and with different encoding algorithms) doesn't translate to identical playback!

Re: iTUNES PLUS SOUNDS POOR ON BEOSOUND 5...

Puncher — Wed, 24 Jun 2009 02:15:54 GMT

If we accept that a computer can open a *.zip or *.rar file without any errors and all data contained in that file is as it was before being compressed why do we consider there to be some special "hoodoo" in a compressed audio file that means that "lossless is not lossless" - I find this incredible!

There are many tests elsewhere on the net that show that the digital data recovered from a lossless audio file (flac, alac, or wma) is bit perfect when compared to the original source. There are also tests where the analogue audio files generated from the original CD and from playback of a lossless codec through the same soundcard/dac are subtracted - the result is, in essence, single-bit noise i.e. the analogue waveforms were identical.

Of course people can choose to believe or disbelieve, this sublect will continue to run and run across audio forums throughout the net however for all the tests I've seen that show lossless is lossless, I can't find any that stand up to scientific scrutiny that show lossless isn't.

Hifi mains cords anyone?

Re: iTUNES PLUS SOUNDS POOR ON BEOSOUND 5...

Stan — Tue, 23 Jun 2009 17:16:32 GMT

I think what you're saying is pretty reasonable (especially when it comes to listening to what you like). However, if bit rate errors were a factor, then computer programs would crash far more often than they do - or maybe this is Microsoft's excuse . For every "bit error rate", there's an "bit error detection and correction" algorithm. If not, digital technology just wouldn't work. I'll accept that bits can get lost in the DAC (who's to know, it's being converted to analog), but not that bits are routinely lost and not corrected in the digital side of the computer.

Stan

Re: iTUNES PLUS SOUNDS POOR ON BEOSOUND 5...

dkresz — Tue, 23 Jun 2009 16:32:18 GMT

Stan, agree with what you say... that was the gist of my comments also. In short, the AAC 256 Kbps - no matter where sourced from - are inferior to AAC lossless (just to keep things simple). But I need to make this point again, lossless is not lossless. There are so many factors at play here besides the advertisement of a mathematical algorithm. Digital information is subject to 'loss of data' due to transport (hence the term: bit error rate). Transport could mean: a digital drive, software used, DAC, bandwidth of the cables and their insulation against electrical / magnetic interference etc. I don't' intend for this thread to extend even further (say, around a digital vs. analogue argument and data buffering & error correction etc) but, in summary, people should buy and listen to what they like and most enjoy. Perception could be a good thing stopping us up over-analyzing things...

Re: iTUNES PLUS SOUNDS POOR ON BEOSOUND 5...

Stan — Tue, 23 Jun 2009 12:44:05 GMT

Personally, I'm skeptical about this whole thread...

Are the record companies *really* re-mastering audio files for the digital age? I find this highly doubtful unless it's something that can be accomplished automatically, and even an automated remastering still costs money for computing power and IT folks to make it happen. Why would a money grubbing record company spend any money on improving the audio sound for run of the mill downloads (i.e. not marketed and priced as "audiophile") when the "general public" has demonstrated that they don't really care about high quality audio?

Does an mp3 ripped from a CD sound any different than an mp3 ripped from "the original audio master"? I assume the audio master is a higher resolution than a CD so, I suppose, this one could hold a little water. An mp3 from a quality source does sound better than an mp3 from a crappy source. However, is the difference *so* great between a CD and the original audio master that they can still be heard after being compressed to 256kbs? Could it be that you're just hearing the difference between 128kbs DRM and 256kbs non-DRM, and the actual source doesn't really matter... Also wouldn't a poor sounding CD also have a poor sounding master? Or have the record companies remastered all of their recordings so people get better sounding compressed mp3s (we're talking about the same company that released the poor CD to begin with... why are they getting audio quality religion just now)?

Does a lossless WMA sound better than a lossless AAC? Lossless is lossless. Plenty of people have performed tests where WAV -> WMA -> WAV (or AIFF -> ALC -> AIFF) results in bit-for-bit identical files before and after. I have read that folks have studied the digital output of the airport express (which uses apple lossless compression for the wireless transmission) and found it to provide bit-for-bit identical rendition of the source. The contention here seems to be that, for playback, something different is happening. A full bit-for-bit rendition of the original source is not making it to the DAC. Once again, there's a window of possibility here, but, again, I'm doubtful. If the codec can produce a bit-for-bit copy to the disk (WAV->WMA->WAV), why not to the DAC? I guess the one possibilty is that the ALC codec on Windows may not be 100% lossless. I have no experience with this codec, but if Apple created it (or licensed it), it seems very doubtful - why would Apple allow their high-end proprietary audio format to sound worse on windows? Is this a strategy to sell more Macs? I'm not buying it... then again, I've not done a direct comparision...

Oh well, we all hear things differently (even when it's the same)...

Stan

Re: iTUNES PLUS SOUNDS POOR ON BEOSOUND 5...

dkresz — Tue, 23 Jun 2009 03:51:38 GMT

Puncher:

OK - I can't say I'm convinced - if there is a difference it says one codec (likely the aac) isn't truly lossless, I don't think the hardware has any effect.

I can assure you there is a difference. I have tested this both on the BM1 and BM5/BS5 (under an audiophile-like setup: i.e. using high-end Shunyata Research power conditioning and cables). In terms of proving that one codec isn't truly "lossless", I am not sure the fact either codec is mathematically calculated to be lossless (and advertised as such) it actually means it is lossless in terms of its end-to-end reproduction (I believe that was the thrust of this entire thread, namely, could we agree on whether you can compare or choose b/w an actual CD vs. a 256 Kbps media file sourced from the audiomaster etc? although, to some extent we were comparing 'apples' and 'oranges' given one was actually tested on the BS9000 and one on the BS5 respectively).

What it would imply though is, there are more "obstacles" encountered by an AAC file played on a Windows-based media player (B&O player in this instance) than there is for a WMA encrypted file. If you'd like, it's like trying to listen to the "same" CD but with different software versions uploaded to the same digital drive unit. The results don't have to be identical (the media source is virtually the same but the decoding / playback software is different). Do the test I say (preferably, when the AAC lossless codec gets supported by the BS5 software).

Re: iTUNES PLUS SOUNDS POOR ON BEOSOUND 5...

Puncher — Tue, 23 Jun 2009 02:07:56 GMT

OK - I can't say I'm convinced - if there is a difference it says one codec (likely the aac) isn't truly lossless, I don't think the hardware has any effect.

As you say, it will be interesting to retest if/when the BM5 officially supports alac.

Re: iTUNES PLUS SOUNDS POOR ON BEOSOUND 5...

dkresz — Mon, 22 Jun 2009 17:42:23 GMT

puncher:

If both 1. & 2. are lossless conversions, to what do you attribute the apparent superioity of the wma lossless file?

Primarily, on a blind test - comparing the same song at the same (lossless) resolution on the BM5. I encourage you to do the same.

Now to the speculative part: one is (mainly) Mac and the other is Windows? The codecs have diiferent encryption / decryption algorithms that are affected by the platform? BM5, being Windows XP Embedded, may be fine-tuned for WMA and WAV playback ? It will be interesting to re-run the same comparison test when the BM5 / BS5 software gets upgraded to officially support AAC lossless...