Saturday, April 24, 2010

Further thoughts on digital audio playback

I have come to realize there is a lot of emotion when it comes to high-end audio. Having been out of the market for some time, it was interesting to see that all the "psycho-acoustic" stuff that used to be debated about turntables has transferred to the digital domain, with audiophiles looking for ways to tweak their systems to improve the sound.

I have to say that as someone who has been building PC's since they were invented, I have a great deal of difficulty with some of the assertions being made about audible effects from various parts of the reproduction chain.

I am a big believer in fidelity to source, and transparency in path.

Since the CD contains a digital file, and the read mechanism is inferior to a hard disk (due to the Redbook (lack of) error correcting), any audible effect is going to come from a failure to read the data correctly, the quality of the DAC, and/or the quality of the analogue output from the CD player.

By eliminating the CD and working with a source digital file, one source of error is gone. With an external DAC, one has a choice based mostly on economics, and then the reason I bought high-end equipment like the Bryston BP26/MM and 4BSST2 is their mastery of the analogue space.

I went with the Logitech Transporter as my digital "player" because I was starting from the streaming problem, not the DAC problem.

I ripped to FLAC as my digital source. When you use a program like dbPoweramp or EAC to do the ripping, you start to see the "read" problem. It is possible to get a different digital file out of successive reads, which attests to the lack of robust error correction and the fragility of the CD as a source. The dpPoweramp software compares the rip against a database of other rips to give you an indication of whether or not you matched the most common result.

Once you do have a clean digital file and store it in the computer domain, there is no chance the source will be affected by moving it between components.

I do understand there is the issue of jitter, but before we go there, just remember that we are routinely typing on message boards using widely different source equipment (PC, MAC, software) across thousands of different networks containing tens of thousands of routers and switches, and yet somehow, without fail, when I hit an "a" I get an "a".

I suppose the digital player is also a possible variable - FLAC is a standard encoding format and lossless, and the decoder is also standard, so a proper implementation should deliver the same bitstream regardless of hardware. As long as you are in the digital domain there can't be anything affecting the source (remember the "a")

Now that I have the whole thing set up, the question would be whether an additional investment in another DAC would be audible to me. I accept that this is personal to everyone, so I only judge with a sample of one.

The real question for me is why the music industry won't sell me a high quality digital source file so that I don't have to go through all this rigmarole to listen to music.

1 comment:

SN said...

Dear Waleed Hanafi,

I am a student at the university of Amsterdam. At this moment I am in the end phase of my study and have started to conduct research for my thesis to complete my master in political science. In my thesis and related research I aim at analyzing blogs in Singapore that focus on Singaporean politics, including for instance political issues, political system critics etc.

I would be very grateful if you could send me the links of the most authoritative or well known and well regarded blogs writing about Singaporean politics you know next to your own blog. Maybe you have friends who also write on these matters. If you could forward my e-mail to them and ask them to respond to me, that would be great. Alternatively you could send me their e-mail address or url so that I can contact them myself.

I have one more request. Is it possible that you would cooperate with me and that you answer some questions I will send to you? The questions will be about blogging in Singapore.

Thank you very much for your help!

Yours sincerely,

Sarah Nienke van Voorthuisen