Meridian Unplugged - Powered by MrTechGuy.co.uk Forums Discussion Meridian - Systems HTPC vs. the need for DVD (or HD-DVD / Blu-Ray)

Isn't the debate here, whether or not all the bit are transmitted perfectly and with perfect timing?

Assuming accurate [edit]delivery[/edit] of disc contents is the only issue, Server vs CD Player essentially comes down to:

Which device reads a CD most accurately?
Which device delivers that data most accurately?

Within those two areas is plenty of potential for sound degradation. CD players use engineering to solve these issues, but this comes at an (increasing) cost. The server's beauty is it's simplicity (ignoring initial setup/ripping issues) and comparitively low cost. Two completely different approaches to solving the same problem.

And once you start comparing other factors such as cost to sound quality ratio and overall convenience the odds start stacking *very* favourably towards the server, IMO.

Cheers,

Mark

Mark,

You still do not get it.

You write:
Which device reads a CD most accurately?
Which device delivers that data most accurately?

In the analogue world we needed to think in terms of “most accurate”. No system was completely accurate. As you got closer to accurate, there was room to talk about the flavor and aroma of the sound.

Digital is a whole new world, you have the bits that were written on disc. Either they get to the speaker or they don`t. They are accurately transmitted or they are not. If you use fancy gold etched wire that is blasted with gamma rays while frozen, you still have the same bits or errors. Any bit that is different from the original is considered an error.

If your CD drive is not reading the bits properly off the disc you need to buy a new CD drive. It is a terrible thing to say but a cheap drive from Wal-Mart will read the same bits as the one in a fancy NY showroom. I worked at a large software company for many years, I wrote code for applications that would read data from a CD, we decompressed just about every byte stream that came off a CD. If we ever found an error we would have to abort the application, only perfection would do. Even your cheapest Wal-Mart computer will get the bits off correctly. Ten years ago this was not a big problem and it certainly is not a very common problem today. And you can test this at home, rip a disc a few times, compare the files with windiff.exe. They will be the same every time, hook your compute up to your stereo, even with “PC power supply induced nastiness and conductive noise through the interconnects” the files will still be the same.

As far as this garbage about jitter, every digital signal has jitter. Every USB, Ethernet, Firewire, HDMI signal. Every signal inside the CPU has jitter, the signal to memory has jitter. As long as the jitter is within the tolerance, all of the bits get transmitted perfectly. The tolerance for Jitter is a very small when you are talking about the HyperTransport between CPU proccesors at 24.0GB/s. It is rarely a problem for digital audio. Here again, if the bits are getting across then reducing jitter make no difference. And just to clarify, jitter is not cumulative.

There are many challenges with digital audio, there are firmware upgrades to deal with, re-sampling within the OS, drivers compatablity, ect.. There are plenty of things to fiddle with, but we do not need to worry about “physically decoupled and so transmits no noise”.

sed,

Reading through your verbiage, it seems you actually agree with me that a digital server should sound as good as *any* digital CD transport. Both are simply serving the same bits taken from the same source. Right?

We'll have to agree to disagree on the causes and the audible effects of jitter on an audio signal.

Cheers,

Mark

I have had a number of music servers and I think they are great. After spending too much time and money on two versions of the Imerge dedicated servers I went the PC route. I spent $600 on a fancy RME sound card and had nothing but problems. It could play music fine but endless problems with audio portion while watching a video. I now have a system with an M-Audio sound card, RAID drives, dual AMD 254 CPU`s a 30” 2560x1600 monitor and a 70” TV. The audio goes though a G68, DSP8000`s front, DSP7000`s rear with a 5500 center.

I use a digital coax from the PC to the G68.

I would not say the system is trouble free. It seems that I have to update the firmware on the G68 too often. In my opinion Windows XP is not really designed for trouble free hi-fi audio. Many things seem more complicated than they should be. Many people have trouble getting DTS to work for example. And then when you get it working and you install some utility to rip DVD`s or convert them it messes up your audio.

Music servers are great and we can only hope that with a copy of 64bit Microsoft Vista all of the problems will go away. Hopefully someday soon they will become so easy to manage that my mom could set one up. I completely agree that music servers can/should sound the same as high dollar transports. There is the caveat that the getting the software/drivers setup so they sound “exactly” the same is more difficult than it should be. The biggest issue for most people is the re-sampling that the OS wants to do. It wants to blend all of the sounds from all of the application together. If you get past the OS re-sampling they should sound exactly the same.

Why is your OS messing with the audio data? You should be passing an unaltered feed direct to your G68, exactly as you would with a CD transport...

Mark

At any given time your PC can be playing audio from any number of applications. By default Windows XP (and Windows 95,NT) will take all of the sound from all of the running applications and resample them to 48k using a driver called KMixer (Kernel Audio Mixer driver).

Ouch! Another argument for using something like the Squeezebox, whether wired or ethernet, for audio applications. The audio file is sent, *unaltered*, to the Squeezebox for relay to it's digital output and onto the processor.

If we now go back to my original statements:

Which device reads a CD most accurately?
Which device delivers that data most accurately?

You have agreed that both a transport and a server should sound as good as each other. You stated that reading CDs is easy (assuming a working transport!). This implies that the server and transport are both as capable as each other of reading accurately from the same source CD and should recover an identical bitstream (once again assuming both transports involved are functioning correctly).

Why then would somebody still claim their transport sounds better than their server or that their server sounds better than their transport? What could be the cause of any sound quality differences between a server and a transport? If they both read accurately, then it must be the delivery of the signal. You have highlighted one type of extreme problem - OS interference with the signal - but assuming both the transport and the server are able to start with the same bitstream, what could possibly cause one to sound different from the other?

Cheers,

Mark

The more threads there are on this subject the more complicated it becomes.

Long live the CD/DVD player

Long live expensive and mediocre sound quality?

So now your server sounds better than a dedicated Meridian transport..... sure?

Slight contradiction!

Jez, I am with you.

A Hard copy disc and somthing to play it on.

My digifusion PVR does sound good though, but the Hard drive capacity is Finite.

I have plenty of people come round mine and they NEVER say the sound is Mediocore!!!!!!!!!!!!!!!!

Computer enthusiasts, Go for it, but I find all the tech talk soooo dull.
Having got into this to listen to great sounding Music and enjoy the Radio and Movies at close to their best.

When you have found and agreed on a simple affordable solution, let us know.

I dont think you ever will though because the 'tech talk' and experimentation is a big part of the pleasure for you. (Which is OK by me)

Cheers, Chris

Not at all. My first statement above was for the sake of discussion. My position has always been clear - the server should always outperform the transport.

Cheers,

Mark