Official DAC Argument Thread

quote:

Originally posted by Andy S:
Only if we can have a "I appreciate all sources equally" thread

Right... because that hasn't been painfully clear.

Seriously though, after your visit with James that thread will be welcomed, and wont require a lick of technobabble either way.

quote:

Originally posted by js:
When I compare, I like to compare to my best source combo which so far has not included a tos.

JS,

Which source would that be?

Also, would you mind posting a short list of your rankings? Just for fun?

thanks,
Patrick

I'm not ranking them. All have been better with coax when available but I avoid switching type supplies.

JS,

Sorry bad question....

Would you mind listing some the transports you've tried and/or like? No ranking required of course.

-patrick

PureHiFi - what evidence have you got that cd's cannot be read accurately by cd transports?

It is the case that you can rip a cd on a variety of cheap rubbishy computer cd transports, usually at many times normal speed, and get a demonstrably bit perfect rip as evidenced by the checksums. Every single bit comes off accurately in exactly the right order.

Are you saying that a NAIM CD transport, costing many times what the cd drive in a pc costs, and having a lot more time to extract the data, might be doing the job wrong?

Here too...apprx after 45 minutes...

Hmmm..my system is setup very well, everything on FRAIM, cable dressing, etc...and still there is a big difference between

USB-stick
CDP
Squeezebox Touch

quote:

Originally posted by likesmusic:
PureHiFi - what evidence have you got that cd's cannot be read accurately by cd transports?

It is the case that you can rip a cd on a variety of cheap rubbishy computer cd transports, usually at many times normal speed, and get a demonstrably bit perfect rip as evidenced by the checksums. Every single bit comes off accurately in exactly the right order.

Are you saying that a NAIM CD transport, costing many times what the cd drive in a pc costs, and having a lot more time to extract the data, might be doing the job wrong?

This is what I was trying to get at if the clock frequency wasn't 100% stable. Maybe it doesn't come off correctly?

Can you count your fingers?

Can you count your fingers when your hands are dirty?

Can you count your fingers when you are wearing gloves?

You don't have to have perfect digits to be able to count them!

quote:

Originally posted by nap-ster:
This is what I was trying to get at if the clock frequency wasn't 100% stable. Maybe it doesn't come off correctly?

Did you miss my response to your post?

Reading data off a CD is a complex control process (e.g you have to spin the disk at different speeds depending on where on the disc you are reading from) but it generally isn't a problem. There are a number of levels of error correction possible before you have to revert to interpolating samples.

If you were having to interpolate data, the effects would not sound like those mentioned (sibilance/crisper drum hits) and they would not always coincide with these events in the music.

quote:

Originally posted by Andy S:

quote:

Originally posted by nap-ster:
This is what I was trying to get at if the clock frequency wasn't 100% stable. Maybe it doesn't come off correctly?

Did you miss my response to your post?

Reading data off a CD is a complex control process (e.g you have to spin the disk at different speeds depending on where on the disc you are reading from) but it generally isn't a problem. There are a number of levels of error correction possible before you have to revert to interpolating samples.

If you were having to interpolate data, the effects would not sound like those mentioned (sibilance/crisper drum hits) and they would not always coincide with these events in the music.

Yes I did, but you have replied again with "generally isn't a problem", which to me reads as "it could be". Why the emphasis for a better clock then? If there was a less "reliable" clock in the transport then surely this would make a difference? Maybe the levels of correction and the control mechanism for reading the data vary from transport to transport?

quote:

Originally posted by nap-ster:
Yes I did, but you have replied again with "generally isn't a problem", which to me reads as "it could be". Why the emphasis for a better clock then? If there was a less "reliable" clock in the transport then surely this would make a difference? Maybe the levels of correction and the control mechanism for reading the data vary from transport to transport?

Generally it isn't a problem means that if the CD is not too damaged, it will get read 100% accurately. Defining when it is too badly damaged is not possible because the data and error recovery information is spread around the disc specifically to allow scratches to be corrected losslessly, so you can't predict if a CD can or can't be read. If you want the gory detail: http://home.btconnect.com/geffers/cd.html What is true is that transport mechanisms/read heads come into the equation here and you might find CDs that play on one player might not on a different make simply because the mechanism isn't "as good" at reading the data in the first place. This isn't a clock related issue though.

Emphasis for the better clock is to reduce jitter in the system as a whole and improve D->A conversion (see my post on P2). It may help with reading, and that will get translated into a lower strain on the power supply which can help improve on D->A, but it's not about getting more reliable data off the CD

As to differing strategies - yes, you can implement more or less complex error recovery algorithms, but this will be in the readout hardware. Given the level of technology involved (late 70's) and the advancement of Silicon design since then (a chip to do complete a/v decoding for SD TV which is many orders of magnitude more complex than this error recovery is only a couple of dollars in volume quantities), I'd expect all but the cheapest controllers to be pretty similar in their implementation of error recovery.

quote:

Originally posted by Andy S:
...Generally it isn't a problem means that if the CD is not too damaged, it will get read 100% accurately....

Hi Andy -

Does this apply to CD drives used for ripping as well? If yes, why is there so much talk about the importance of accurate RIPs?

I recall reading an article in one of the Hi-Fi mags a while back where they did bit-for-bit compares between files created by different rippers and found no differences. Since then, I've just used MediaMonkey's ripper for convenience (organization and tagging). Only when MM gags have I resorted to using EAC.

Bad strategy?

Thanks.

Hook

Maybe the white paper itself is not bit perfect?

quote:

Originally posted by ghook2020:

quote:

Originally posted by Andy S:
...Generally it isn't a problem means that if the CD is not too damaged, it will get read 100% accurately....

Hi Andy -

Does this apply to CD drives used for ripping as well? If yes, why is there so much talk about the importance of accurate RIPs?

Yes, it does. As to importance of accurate rips - well, it'd be difficult to tell when you've actually ripped something incorrectly or how badly it's been ripped if you don't check it with something. It's all about confidence of the underlying source data (rip it once, rip it well).

quote:

I recall reading an article in one of the Hi-Fi mags a while back where they did bit-for-bit compares between files created by different rippers and found no differences. Since then, I've just used MediaMonkey's ripper for convenience (organization and tagging). Only when MM gags have I resorted to using EAC.

Bad strategy?

Depends on the quality (how much damage they have) of your CDs. I use REACT (which is a mod to EAC) and that rips using EAC and manages all tagging (I use FLAC) and even drops out a copy of the tracks as MP3s for the Cowon. Takes 2 clicks... I had about 400 CDs to rip, so it wasn't too much of a hardship to wait for EAC to do it's bit (plus my drive is fairly quick with EAC anyway)

quote:

Originally posted by nap-ster:
Maybe the white paper itself is not bit perfect?

Maybe, but it does hang together well... Still, something must be causing differences to be heard.

quote:

Originally posted by ghook2020:

quote:

Originally posted by js:
True but there is a clear difference. It's also been mentioned regarding the PCI upgrade for the HDX. Not only are there differences, Naim apparently understands why and how to optimise. That they don't fill us and competitors in on every nuance is understandable. Sales are about being able to dem and hear a difference, not some extensive explanation of life, the universe and everything which is about what it would take to cover all the bases. Look at the last thread to see how poorly that goes over other than as an exercise.

Yeah, but if a customer asks you: Why does that 500 cost so much more than the 100, do you simply demo it? Don't you also have to tell the customer the whole story in order to help them grasp the uniqueness and value of the high-end?

I do appreciate that Naim walks a fine line when it comes to disclosure. Competition is fierce, statements can be taken out of context and used against them, etc.

But if a company representative is willing to say something in a public setting, then they should be willing to put it in writing.

And oh yeah, the last thread did not go over well simply because people took Andy's technical arguments personally. Even though he never told anybody that they weren't hearing differences, people inferred from his arguments that they he was calling them liars.

Hook

No. I don't need to explain what's going on in a $30k amp. I think someone looking for a value purchase is not thinking 500 and many are not technical. Much is assumed about construction and I may get into the differences of Naim vs other makes design philosophies and the obvious outboard supply etc. but proof here is in the listen where it belongs.

As for the last discussion, Placebo was the word. I don't think anyone thought Andy was calling them a liar, just dilusional. It's useless in a discussion. You're dilusional, I win! That's why I said "no it's not" is just as valid. Not Liar but it's still a put down. I also believe there are reasons some don't hear differences but I don't think it's their hearing or dilusion. It has to do with setup driven by technical beliefs of what does and doesn't matter. It's sensible but perhaps there's more to it and we don't know everything.

This sounds a lot better on the DAC


It's sunny outside! Have a good weekend y'all