Digital to analog converter

[Dartas]

Hi,

I have a doubth..

People tend to say that digital sorces, via optical or coaxial, are all about "Zeros and Ones", and it's the DAC on the amplifier (or an external dac) that will convert it into analog.

If this is all that simple, using an exterbal DAC it would be just the same thing to play my audio CD's via my Samsung Blu-ray than it is played by my dedicated Cambridge CD player.. But something tells me that it's not that simple, is it?

Would really like to hear your thoughts about this :scratch:

[losenotaminute]

Hi,

I have a doubth..

People tend to say that digital sorces, via optical or coaxial, are all about "Zeros and Ones", and it's the DAC on the amplifier (or an external dac) that will convert it into analog.

If this is all that simple, using an exterbal DAC it would be just the same thing to play my audio CD's via my Samsung Blu-ray than it is played by my dedicated Cambridge CD player.. But something tells me that it's not that simple, is it?

Would really like to hear your thoughts about this :scratch:

Yes, I personally believe that it is that simple. You can use any cheap CD transport to read the CD, the quality of the DAC is much more important.

Lawrence

[StanleyB]

Hi Mayo,

the digital to analogue converter in the DVD player can be compared to a beefburger. There is a bit of beef, maybe also a bit of horse, some fat, and who knows what else.
An external DAC is like a piece of steak. Nothing else. How the DAC sounds is like comparing to how the steak is prepared. So different DACs have different flavours and taste.

[Oldpinkman]

I think stan missed the point. A good dac is better than a cooking dac such as many integrated players have for sure. But I think the question was does it matter which transport you use with a good dac?
In my experience - no. My recent experience is limited. 20 odd years ago I carted dacapo into more than a few dealers and plugged it into an exotic collection of transports. All sounded the same.

Unlike cable burn in you can measure quite evident differences - but with dacapo I didn't notice any enough to bother me. :)

[wee tee cee]

In my experience transports can sound quite different if we include PCs and dedicated music servers then the choice widens.
The thread is entitled DAC, if the poster can get a hold a few DACs (any AOS members willing to help?) the differences again are quite noticeable.

You really don't have to spend a great deal of money to achieve very high audio standards, plenty of threads on this forum to get a flavour of what's on offer.

[bobbasrah]

CD or HDD or SD cards are digital storage media. The translation of the data into audio is where the variations can arise, or as Stan put it nicely, flavours. However, the home laptop uses an external drive and an external DAC, as did the Lenovo at work.
Due to recent genny brainfart at work, the power supplies to laptop etc got blown, so backed up some music onto the work laptop... Was rather surprised to find that the sound quality direct off the Lenovo's hard drive sounded better than from the external drive, the exact opposite to that at home...
Still digital, still accurate, just different and a little clearer, only one variable...

[StanleyB]

Talking about laptop: based on my experience the firewall, virus checker, and number of CPU cores in use by the laptop can alter the sound.

[DSJR]

I think that DAC chips are almost pretty well sorted now, at least for slow old domestic audio. How these chaps are used however, can make a difference I believe.

[StanleyB]

I think that DAC chips are almost pretty well sorted now, at least for slow old domestic audio. How these chaps are used however, can make a difference I believe.
They are not sorted yet. It takes a lot of effort to get them to play ball. Worse still is the lack of knowledge at the manufacturer's support end.

I'll quote from an email I sent recently to get some technical info.

Me:
Hi xxxx,

By the way can you find out for me about the I2C, SPI, and GPIO technical information to operate the XXXX via software mode?

Reply:
Hi Stan,

In order to give you a proper answer, would you please provide me more detailed information about your question, because now we cannot clearly understand it?

That about sums it up. Most of the stuff I use to get the best out of the chips I have to personally dig up. But messing about with interrogating DAC chips via I2C etc is a high risk strategy. It's easy to blow the chip up or put it in a locked state. Then it's a case of binning it and trying with a new chip if I can't get it to reset.
But when it does work, the heavens can open up and shower you with huge rewards.

[bobbasrah]

Talking about laptop: based on my experience the firewall, virus checker, and number of CPU cores in use by the laptop can alter the sound.

Yes Stan, but this is the same machine, only difference was that the feed was from internal HDD rather than external. May well be that the internal architecture and OS on the home one proved external HDD was better, this other machine is the reverse, I just never tried it that way. Like we discussed previously, no two setups will be identical on a hardware or software basis...

[Dartas]

Hi Mayo,

the digital to analogue converter in the DVD player can be compared to a beefburger. There is a bit of beef, maybe also a bit of horse, some fat, and who knows what else.
An external DAC is like a piece of steak. Nothing else. How the DAC sounds is like comparing to how the steak is prepared. So different DACs have different flavours and taste.


Yes, I personally believe that it is that simple. You can use any cheap CD transport to read the CD, the quality of the DAC is much more important.

Lawrence

So basicaly, if i use a good quality dac, it's completly indiferent if i use a £1000 cd player or a cheap £50 blu-ray player as a transport?
Is it that simple??

[StanleyB]

I use a £30 DVD player from Tesco to play CD and DVD in my office. The audio is processed by a TC-7533.

[losenotaminute]

So basicaly, if i use a good quality dac, it's completly indiferent if i use a £1000 cd player or a cheap £50 blu-ray player as a transport?
Is it that simple??

Maybe not completely, but the difference you will hear will be more affected by the DAC. I don't really understand how a digital signal could be affected by the type of transport or the quality of cabling, but I am a vinyl listener and am only basing this view on what I think should be the case. Not really interested in debating this if it turns into a bun fight :-)
Lawrence

[Dartas]

I use a £30 DVD player from Tesco to play CD and DVD in my office. The audio is processed by a TC-7533.

Seriously?? :stalks:

I'm asking that because i have a guy interested to buy my CA dedicated CD player, and i´m trying to decide if i should sell it or not.
This because i'm planning to complete my order for a BM mkII as soon as i get back from holidays (hope you didn't take me out from the list yet), and if my Blu-ray player will do the same job (via the BM) i will just sell the CD player to reduce the number of boxes at my rack :D

[John]

In my experience the Transport plays a difference towards SQ but also think they are a few ways round this

[Dartas]

Maybe not completely, but the difference you will hear will be more affected by the DAC. I don't really understand how a digital signal could be affected by the type of transport or the quality of cabling, but I am a vinyl listener and am only basing this view on what I think should be the case. Not really interested in debating this if it turns into a bun fight :-)
Lawrence

Yes, indeed if it is just zeros and one like people say, it should not matter what transport it is as long as we use a digital output, but i'm not actually sure of that...
Unless some players can send bigger ZEROS and bigger ONE's then others, which doen't seams to make much sense :scratch:

[Dartas]

In my experience the Transport plays a difference towards SQ but also think they are a few ways round this

Can you explain why?

[StanleyB]

Maybe not completely, but the difference you will hear will be more affected by the DAC. I don't really understand how a digital signal could be affected by the type of transport or the quality of cabling, but I am a vinyl listener and am only basing this view on what I think should be the case.
Jitter. A good scope will show up the effect.

[StanleyB]

Unless some players can send bigger ZEROS and bigger ONE's then others, which doen't seams to make much sense :scratch:
The speed adjustment feature on some CD players (like the DJ type players) relies on this feature. The clock frequency of the data signal is changed which in turn can speed up or slow down the sound. So it is like bigger or smaller zeros and ones in that case.

[John]

I am biasing my experience more on the computer side of audio for me the effects are very strong
I currently use a Sony Blue ray player using external usb HD I find this a lot better than using it as a CD player with the Bushmaster mk II
So I am burning CD files and playing them as WAV on the player and get a lot better results. Sorry not really technical but presume less jitter issues

[Dartas]

I am biasing my experience more on the computer side of audio for me the effects are very strong
I currently use a Sony Blue ray player using external usb HD I find this a lot better than using it as a CD player with the Bushmaster mk II
So I am burning CD files and playing them as WAV on the player and get a lot better results. Sorry not really technical but presume less jitter issues

Humm.. this is interesting because it's not the first time i hear someone saying that. Also people talck a lot about Flac files which i really have to read more about, but i think it's more or less something like what you've described

[bobbasrah]

Think you need to realise that the flac v wav issue however reported has to be viewed in context as it appears to depend on the computer etc used. Unlike John I have experienced no such issues, but you are looking at a CD player not a server, so this should not be a problem.

So long as the optical spinner translates the data on the disc into a digital stream accurately, whether that be optical or coaxial, the dedicated DAC to which that stream is fed will be less compromised and will 90% of the time do a better translation to audio than most onboard DACs ever will...

If Stan's Tesco player satisfies his critical ear, it rather highlights where the money is better focussed... If you trawl the DIY audio sites you will also find plenty of instances of significantly upgraded CD players by dint of changing the DAC within...

[Yomanze]

I use a £30 DVD player from Tesco to play CD and DVD in my office. The audio is processed by a TC-7533.

Hmm have tried using cheapie DVD players (Toshiba, Sony etc.) & they never sounded as natural as my Pioneer DV-717 (including with a series of Beresford DACs).

[StanleyB]

One of the reason I use a dirt cheap set up in my lab is because I want to be sure that any improvements through even a basic system are not reliant on guess work and extended listening session over hundreds of hours. I don't have that sort of time to decide if a component I change on a PCB is better or worse. It has to be an instant result for me. So whilst the cost at £30 would put it in the desperately poor show bracket, it is a very good indicator of what can be expected if a far more costly piece of AV equipment is used instead.

[sq225917]

Me:
Hi xxxx,

By the way can you find out for me about the I2C, SPI, and GPIO technical information to operate the XXXX via software mode?

Reply:
Hi Stan,

In order to give you a proper answer, would you please provide me more detailed information about your question, because now we cannot clearly understand it?




Stan, maybe if you rephrased the question they might understand. Why not try asking them this. "I'm looking to operate the XXXX via its software mode interface and would appreciate if you could supply me with I2c bus, SPI and GPIO technical information to help further my investigations. That said one would assume all you need to know, assuming a high enough level of user skill, is included in the dev kit already.

[Yomanze]

I think that DAC chips are almost pretty well sorted now, at least for slow old domestic audio. How these chaps are used however, can make a difference I believe.

DAC chips have always been sorted, it's the implementation that hasn't. Fair enough they're a lot more integrated now, but there are still many advocates of multibit DACs in current production units. The reason you don't find many multibit DACs around these days is because they're a lot more expensive to make than delta/sigma DACs. Modern DACs still sound sufficiently different to one another though (compare a Sabre to a Wolfson to a Burr Brown)... Anyway, I agree, as you say it's how these chips are used. Stan's done the right thing by omitting an unnecessary output stage, and indeed another forum member some years ago had great success from my recommendation to bypass their Quad 67 player's output stage with a resistor and cap to ground.

[StanleyB]

Stan, maybe if you rephrased the question they might understand. Why not try asking them this. "I'm looking to operate the XXXX via its software mode interface and would appreciate if you could supply me with I2c bus, SPI and GPIO technical information to help further my investigations. That said one would assume all you need to know, assuming a high enough level of user skill, is included in the dev kit already.
Good call, and I am actually working on an email that might get a better response from them. These technical sales people are often scared to ask anyone around them what the question means just in case they are blamed for poor sales. I worked in an environment like that a few times.
If this chip wasn't so full of useful features I might have just let it pass. But it is the most feature packed chip I have ever come across for audio application.
The development board only has a PC control software. That's no use to me since I want to control it with a PC chip. The NDA is also the most complicated I have ever seen. They wanted my wife's signature as well in case she opened any mail from them :mental:.