Jitter the killer of digital audio

[seafire]

Ok with my somewhat heated entry onto this forum I thought I could post a genuine contribution for all serious audiophiles.I had the privilege to hear this product in action during a recent visit to Germany.The before and after results are nothing short of astounding and many will for the first time realize what the problem with cd has been all along.The only way to describe it is..think of your best sounding vinyl and now imagine this with no surface scratches and even more dynamics and extension.No.1 on my list of future have to gets
seafire;)
link: www.jitter.de
Also check out this guy's other machines under ALtmann Micro Machines

[heiney9]

Jitter is a real issue not to be taken lightly. That's one of the differences between a good DAC and a great DAC.

The link you posted while old (as in seen it before a while ago and posted it myself here several years ago) is still a good explanation. I wouldn't buy any of his products......a Monarchy DIP (digital interphase processor) is a great little unit you put between a transport and an outboard dac to reduce clock induced jitter. There are many kinds of jitter with clock induced being the most damaging, (ie; most audible) IMHO.

H9

[tonyb]

Not like it's the first time we discussed jitter,but I agree,overlooked often.

[Flash21]

Just an odd thought, probably way off base, but - would jitter in any way explain how different digital interconnects can sound different? In other words, can jitter be introduced during transmission of a digital signal?

[heiney9]

The only way to describe it is..think of your best sounding vinyl and now imagine this with no surface scratches and even more dynamics and extension.No.1 on my list of future have to gets
seafire;)
link: www.jitter.de
Also check out this guy's other machines under ALtmann Micro Machines

That's not at all how I would describe it. It's more of a hard edge or "glare" added to the music.....a type of distortion that can grate on you and cause listening fatigue if it's severe.

Changes are subtle at best, but they are there none the less when using higher end digital gear with excellent jitter chracteristics.

[seafire]

H9 just out of interest why wouldn't you buy any of his products? I take it that you have found cheaper alternatives.All I can say is what I heard blew me away and I was there on business so havent bought the units yet;)

[seafire]

Just an odd thought, probably way off base, but - would jitter in any way explain how different digital interconnects can sound different? In other words, can jitter be introduced during transmission of a digital signal?
Yes absolutely correct;)

[heiney9]

Just an odd thought, probably way off base, but - would jitter in any way explain how different digital interconnects can sound different? In other words, can jitter be introduced during transmission of a digital signal?

That's a highly debatable portion of the jitter issue. Can't say one way or the other.

Clock induced jitter is the most common and most noticable to the ear and the most easily corrected by way of better built A/D D/A conversion circuits or by use of an outboard re-clocking unit like the Monarchy.

H9

P.s. I'm out of this one as it is another highly charged debate among audio enthusiasts. Seafire is batting 1000 if he's trying to stir things up.

[seafire]

That's not at all how I would describe it. It's more of a hard edge or "glare" added to the music.....a type of distortion that can grate on you and cause listening fatigue if it's severe.

Changes are subtle at best, but they are there none the less when using higher end digital gear with excellent jitter chracteristics.
On what I heard changes were subtle on high end external Dacs but still audible.But what blew me away were the changes it made to hi end and middle class Cd players :eek:

[seafire]

That's a highly debatable portion of the jitter issue. Can't say one way or the other.

Clock induced jitter is the most common and most noticable to the ear and the most easily corrected by way of better built A/D D/A conversion circuits or by use of an outboard re-clocking unit like the Monarchy.

H9

P.s. I'm out of this one as it is another highly charged debate among audio enthusiasts. Seafire is batting 1000 if he's trying to stir things up.
H9 please believe I am not trying to stir and if it is a highly debated subject I will withdraw right now:confused:

[GV#27]

In other words, can jitter be introduced during transmission of a digital signal?Absolutely.Transmiting the digital data via the SPDIF interface (coax/toslink)does introduce jitter because the clock and data signals get combined and transmitted together on a single conductor instead of individually.Timing errors occur when the input reciever chip of the DAC unit has to separate the clock and data signals at the recieving end.

[Flash21]

Well I am just fishing for an easy explanation, I guess you are saying there isn't an easy explanation...

I went to the link like a good little Polkster and found references to "line-induced jitter", although the explanation wasn't very satisfying.


...transmission of a digital signal... will add jitter to our signal whether we use a coaxial cable TOSLINK or SToptical interfaces.

Funny enough, all these interfaces behave different and add different kinds of jitter (different in jitter amplitude, waveform, frequency distribution, correlation).

So now you have the answer to the following questions:

* Why do different digital interfaces sound different, although they carry exactly the same information?
* Why do different cable lenghts sound different?
* Why do some coaxial cables of the same lenght but different manufacturers sound different?

This is line induced jitter.

Guess I'll have to look into this a little more carefully. I'm not all that worried about it, I don't currently have any digital interconnects in my system. But someday I expect I will have a music server hooked to my Cambridge 840C...

[heiney9]

Ok, you I do agree that jitter is an issue that is overlooked and there are ways to reduce it and it can be heard.

I have experience with the Monarchy unit. It's not that I wouldn't buy his.....I'd need to do more research about his product. Reducing jitter is no small task and to be honest looking at his product it looks a little to simpleton to me.

[seafire]

I speak under correction but from what I understand you are correct in saying clock based jitter is the biggest problem.Followed by noise induced jitter like noisy power supplies and ac supply line noise.Then from what I understand you have jitter introduced at any point where the signal changes medium.They say that even the cd motor noise and vibration contribute to jitter AGAIN I SPEAK UNDER CORRECTION and stand to be corrected;)

[seafire]

Where can I read up about the Monarchy unit?

[GV#27]

I speak under correction but from what I understand you are correct in saying clock based jitter is the biggest problem.
All jitter is clock based as it is the result of timing errors.

[seafire]

Absolutely.Transmiting the digital data via the SPDIF interface (coax/toslink)does introduce jitter because the clock and data signals get combined and transmitted together on a single conductor instead of individually.Timing errors occur when the input reciever chip of the DAC unit has to separate the clock and data signals at the recieving end.
Hmm I'm also learning as we go along;)All I can say is that I have heard these units and am purchasing before year end.For H9 I think they have dealers in the States..maybe worth a follow up and give it an audition and come back with your thoughts:)

[ben62670]

Jitter is why I prefer coax over toslink. Two less conversions is two less areas that can throw timing off.

[GV#27]

Where can I read up about the Monarchy unit?IMO the best type of add on jitter reduction is one that uses a sample rate converter IC or ASRC.

[steveinaz]

Cable reflection error in digital coax's can also be a source of cable-induced jitter. From what I have read, use a well-specified 75ohm cable, at least 1mtr in length to reduce this effect.

Stereophile did a very interesting study on cable-induced jitter; they found that cheap coaxial cables (cheap as in construction) were actually "directional" in that plugging the cable one way would show very high levels of jitter, but switching the cable around would reduce it significantly--interesting. Better quality cables didn't benefit from swapping direction, but their jitter specs were good from the start. They had no explanation and were dumbfounded by the finding.

[seafire]

All jitter is clock based as it is the result of timing errors.
Right I think I get you.Although they are introduced at various points and because of various reasons the end result always relates to the master clock timing being out of synch..Am I getting it???:confused:

[seafire]

Jitter is why I prefer coax over toslink. Two less conversions is two less areas that can throw timing off.
Makes sense;)

[steveinaz]

Think of jitter as an unfocused camera; because of timing errors the signal is smeared, so to speak.

[GV#27]

Right I think I get you.Although they are introduced at various points and because of various reasons the end result always relates to the master clock timing being out of synch..Am I getting it???:confused:Put simply Yes.

[steveinaz]

Jitter is why I prefer coax over toslink. Two less conversions is two less areas that can throw timing off.

There is another camp of thought that says because Toslink cannot suffer from cable reflections, it's immune to cable-induced jitter. Is this beneficial? hell I don't know, I'm a dumb warehouse guy.

[GV#27]

There is another camp of thought that says because Toslink cannot suffer from cable reflections, it's immune to cable-induced jitter.But both can suffer from the shortcomings of the SP/DIF transmitter /reciever inferface.

[seafire]

There is another camp of thought that says because Toslink cannot suffer from cable reflections, it's immune to cable-induced jitter. Is this beneficial? hell I don't know, I'm a dumb warehouse guy.
Ok but remember that it goes through two extra conversions and so is exposed to more jitter as Ben pointed out

[steveinaz]

True. Is the extra conversion a factor? I don't know...

[seafire]

Years back I read a article on tweaking cd players in this case a Sony cdp 990 .I ordered a higher quality power supply from Rs electronics and also re mounted this far away from the Dacs.I then proceeded in applying Blu tack to every mountable place on the cd drive and added a copper plate between the power supply and the rest.The Player sounded much better and today I realize I must have improved the jitter.I still use Blu tack on all my cd players and computer drives and I swear it makes a difference
I dont know what it's called in the US but its the stuff we use to stick posters to the wall:)

[GV#27]

Im betting the difference was the power supply:)

[steveinaz]

me two's.

[seafire]

But both can suffer from the shortcomings of the SP/DIF transmitter /reciever inferface.

So what would be the answer?(Besides me forking out the cash for these units)

[steveinaz]

I think GV is saying a better quality DAC and/or CDP would have better quality interfaces--thus, less of a concern. This is what the extra cash buys I would imagine; not to mention beefier/better isolated power supplies.

In other words, there's no free ride in audio.

My personal belief---and I WILL catch hell for this--if you're not spending at least $1000 on an external DAC, you are wasting your time. That's just my experience talking. There are quite a few sub $1000 CD Players that will perform every bit as well as any sub $1000 DAC hooked to a mediocre transport. The Rotel RCD-1072 is 1 example.

[ben62670]

Im betting the difference was the power supply:)

Don't get me going. I will end up modding my CDP's PS next:eek: If from what I have seen in the DAC project I received from you the Toslink converion is the same signal as the optical, but at the jack it is converted to optical? A simple mod to convert to coax?

[seafire]

Im betting the difference was the power supply:)
I hear you I wouldnt know but it really did sound much better;)

[seafire]

LOL I just got this vision reading Bens reply.We must all have very understanding wives (well mine thinks I am crazy).It's like..what are you doing? you just bought that cd player last week.Why is it all in pieces?I have had it with you It's always this tinkering or you are on that bloody pc on some or other forum.Then late at night when me and the kids are sleeping you play the music until wee hours of the morning:oSound familiar guys?:D

[steveinaz]

Don't get me going. I will end up modding my CDP's PS next:eek: If from what I have seen in the DAC project I received from you the Toslink converion is the same signal as the optical, but at the jack it is converted to optical? A simple mod to convert to coax?

Ben, there is white-paper on Benchmark Medias website that shows how to covert a Toslink output to coaxial. http://www.benchmarkmedia.com/appnotes-d/cdjeep.html

[steveinaz]

LOL I just got this vision reading Bens reply.We must all have very understanding wives (well mine thinks I am crazy).It's like..what are you doing? you just bought that cd player last week.Why is it all in pieces?I have had it with you It's always this tinkering or you are on that bloody pc on some or other forum.Then late at night when me and the kids are sleeping you play the music until wee hours of the morning:oSound familiar guys?:D

My wife never asks me how much something cost (I think she is scared to ask) but she finds out later by asking the question "so how much are you selling the Placette for?" When I told her $685, she said "holy shit, how much was it new? It's just a black box with a switch thingy on it" I took out the trash immediately. :D

[seafire]

Oh yes I have more to add.Wife ... do you perhaps now what happened to all the blu tack? the kids need it for a school project? Me no:rolleyes:Wife : That's odd cause I bought about ten packs a week ago...somebody is stealing our blu tack out of our house.Can only be one of your crazy hi fi buddies:cool:

[seafire]

my wife never asks me how much something cost (i think she is scared to ask) but she finds out later by asking the question "so how much are you selling the placette for?" when i told her $685, she said "holy shit, how much was it new? It's just a black box with a switch thingy on it" i took out the trash immediately. :d
lol:d

[seafire]

Hey Steve aren't you supposed to be glued in front of you gear tonight ?:)

[GV#27]

So what would be the answer?(Besides me forking out the cash for these units)

The better DAC's like Benchmarks DAC1 varitants and Bryston's BDA 1 use a sample rate convereter IC's at there inputs which reduce jitter to very low levels.Basically the chip rewrites the data and has it's own internal clock, so is independant from the transports clock.
CDP's have less issues with jitter because the data and clock's are always kept separate(except at the digital outputs).

[seafire]

The better DAC's like Benchmarks DAC1 varitants and Bryston's BDA 1 or the use a sample rate convereter IC's at there inputs which reduce jitter to very low levels.Basically the chip rewrites the data and has it's own internal clock, so is independant from the transports clock.
CDP's have less issues with jitter because the data and clock's are always kept separate(except at the digital outputs).Interesting makes some sense as the listening I did was with CDP'S using their coaxial outs;)

[GV#27]

If from what I have seen in the DAC project I received from you the Toslink converion is the same signal as the optical, but at the jack it is converted to optical?Toslink is optical.The Tos comes from it being a Toshiba development.

[187CAM]

Jitter is a real issue not to be taken lightly. That's one of the differences between a good DAC and a great DAC.

The link you posted while old (as in seen it before a while ago and posted it myself here several years ago) is still a good explanation. I wouldn't buy any of his products......a Monarchy DIP (digital interphase processor) is a great little unit you put between a transport and an outboard dac to reduce clock induced jitter. There are many kinds of jitter with clock induced being the most damaging, (ie; most audible) IMHO.

H9

+1 on the Monarchy DIP. A great piece of gear at a reasonable price. The classic or the 48/96 upsampler are both great pieces.

[BlueFox]

This is what Benchmark does for jitter with the Dac1.

"The DAC1 is a reference-quality, 2-channel 192-kHz 24-bit audio digital-to-analog converter featuring Benchmark’s UltraLock™ technology."

"The Benchmark UltraLock™ system is 100% jitter immune. The D/A conversion clock is totally isolated from the AES/EBU digital audio clocks in a topology that outperforms two-stage PLL designs. In fact, no jitter-induced artifacts can be detected using an Audio Precision System 2 Cascade test set. Measurement limits include detection of artifacts as low as -140 dBFS, application of jitter amplitudes as high as 12.75 unit intervals (UI) and application of jitter over a frequency range of 2 Hz to 200 kHz. Any AES/EBU signal that can be decoded by the AES/EBU receiver will be reproduced without the addition of any measurable jitter artifacts. In addition, the receiver IC has been selected for its ability to decode AES/EBU signals in the presence of very high levels of jitter."

http://www.benchmarkmedia.com/system1/files/documents/DAC1_-_Manual_-_Rev_L.pdf

[steveinaz]

Hey Steve aren't you supposed to be glued in front of you gear tonight ?:)
It's playing as we speak...Diana Krall Live in Paris at the moment.

[seafire]

GV I have a self built music server Intel motherboard etc etc.I use the coaxial out into a Denon 3805 so using the Denons dacs.I discovered a audio program called ASIO 4 ALL .Wow what a difference in sound quality.You really have to try hard now to hear the diff between music server and systems cd player (Marantz cd 7300).Ever heard of it ? ASIO SOFTWARE

[seafire]

It's playing as we speak...Diana Krall Live in Paris at the moment.
Cool Me and the missus enjoy her music;) Enjoy I'm actually jealous ..there is nothing nicer than introducing new gear to the rig especially if it's good stuff like in this case:p

[seafire]

Gv this is not my 2 channel rig but I sometimes use it too for 2 channel use.I think ASIO corrects jitter (jitter correlation ) or something of the sorts:rolleyes:

[seafire]

Cool Me and the missus enjoy her music;) Enjoy I'm actually jealous ..there is nothing nicer than introducing new gear to the rig especially if it's good stuff like in this case:p

What are you using as your Cd drive?

[GV#27]

.Ever heard of it ? ASIO SOFTWARENo I have not ,I have'nt made the step into PC music server territory yet.You have given me a research assignment.

[seafire]

No I have not ,I have'nt made the step into PC music server territory yet.You have given me a research assignment.
Good ;).I have x2 terrabyte hds so all my music is HQ wav format;)I dont use mp3;)

[seafire]

This is what Benchmark does for jitter with the Dac1.

"The DAC1 is a reference-quality, 2-channel 192-kHz 24-bit audio digital-to-analog converter featuring Benchmark’s UltraLock™ technology."

"The Benchmark UltraLock™ system is 100% jitter immune. The D/A conversion clock is totally isolated from the AES/EBU digital audio clocks in a topology that outperforms two-stage PLL designs. In fact, no jitter-induced artifacts can be detected using an Audio Precision System 2 Cascade test set. Measurement limits include detection of artifacts as low as -140 dBFS, application of jitter amplitudes as high as 12.75 unit intervals (UI) and application of jitter over a frequency range of 2 Hz to 200 kHz. Any AES/EBU signal that can be decoded by the AES/EBU receiver will be reproduced without the addition of any measurable jitter artifacts. In addition, the receiver IC has been selected for its ability to decode AES/EBU signals in the presence of very high levels of jitter."

http://www.benchmarkmedia.com/system1/files/documents/DAC1_-_Manual_-_Rev_L.pdf
WOW that's amazing now even more jealous:o

[steveinaz]

What are you using as your Cd drive?

C.E.C. CD-3300 CD Player.

[madmax]

I notice a lot more jitter after the second cup. So, do you get less or no jitter when you read a hard drive, vs a CD?
madmax

[LuSh]

I'm not sure about Benchmark's claim. I've used a Museatex Transport and a Blu Ray player both as transports and the Museatex was miles head of the Blu Ray, both used the same 75 Ohm Cable from Stereovox. Both transports were fed into a Benchmark, the differences were not subtle. The first and most obvious difference would be in the power supply's of the two units however I suspect there is less jitter coming out of the old Meitner transport.

UHF magazine has done tests on jitter via SPDIF connections, they've measured differences by the same brand in different lengths. Their conclusion was 1.5 meters was ideal if I remember correctly. This length was tested with a number of competing manufactures and always sounded best and measured the best.

[TECHNOKID]

Jitter is why I prefer coax over toslink. Two less conversions is two less areas that can throw timing off.
+1 on your comment.

[TECHNOKID]

Think of jitter as an unfocused camera; because of timing errors the signal is smeared, so to speak.I like the comparision. Timing and synchronisation can greatly improve a signal but can also be a nightmare when it breaks loose.

[TECHNOKID]

True. Is the extra conversion a factor? I don't know...From learning any type of conversion has drawbacks. I think conversion should be done only when necessary and avoided when possible. While coax is considered as analogue cabling, its ability to process digital signals is very interesting.

[TECHNOKID]

Im betting the difference was the power supply:)Who knows, it could have acted as an effective dielectric?

[GV#27]

Who knows, it could have acted as an effective dielectric?While I don't know the specifics of Seafires power supply upgrade,my own personal expierience with such mod's would lead me to believe the improvements were the result of installing a better power supply/voltage regulator scheme.

[ben62670]

Ben, there is white-paper on Benchmark Medias website that shows how to covert a Toslink output to coaxial. http://www.benchmarkmedia.com/appnotes-d/cdjeep.html

Thanks Steve. I wll take a peek at my sony changer sometime soon.


Toslink is optical.The Tos comes from it being a Toshiba development.

Yeah I meant optical to COAX;)

[GV#27]

Yeah I meant optical to COAX;)The signal is the same right up to that little black box,it does the conversion to optical.Your 1792 board has both coax and toslink,or do you have a transport with only Tos?

[ben62670]

Yeah my Sony CD changer is Tos only. I am thinking about ditching it. To mount an optical on the DAC would most likely be about the same amount of work as converting the Sony to COAX. I'll poke around later. You get the email on the boards?

[Flash21]

Heh, I have to laugh...I should have known that digital cables would have as many points of contention as anything else in this crazy, um, hobby... :p

As Dave Barry said: "It's a fine line between hobby and mental illness."

[ben62670]

Heh, I have to laugh...I should have known that digital cables would have as many points of contention as anything else in this crazy, um, hobby... :p

As Dave Barry said: "It's a fine line between hobby and mental illness."

Glad to entertain:) The difference between computer digital, and audio digital is that timing is an issue. With computer type digital the packets are just reassembled at the other end. With audio timing has an effect on SQ.
Enjoy.
Ben

[sucks2beme]

I was about to buy a better quality CDP, when I switched gears.
I went to a NOS DAC via USB, using pc with lossless FLAC and
ASIO4ALL to bypass Windows crap. The result was pretty good.
I'm watching for that killer DAC deal that I know is out there.

I then went back and installed FRED diodes in the power supplies
of two of my CDP's. I also changed out some 5332 chips in the AMC.
That resulted in some good gains in the sound.
The fast recovery diodes helped bass, while removing muting transistors
on the AMC output helped increase top end sound.
While jitter may be a problem, there's a lot of other places to get good
gains in sound. Most CDP's have a lot of other weak points on the power
supply and analog side to contend with. Of course, a good external
DAC would fix most of that. It's a never ending game. There's always
a weakest link.

[ben62670]

What did you change the 5332 chips to? I am a big fan of the OPA134/2134 chips. For the price of $2 each it is a silly cheap mod to do on gear. Very dynamic, and great sound stage, but the mids are a little rough. I can't even be sure if that is attributed to other gear to be fair.
Ben

[GV#27]

..I should have known that digital cables would have as many points of contention as anything else in this crazy, um, hobby... :pAtleast it didn't end up in a flame war.

As Dave Barry said: "It's a fine line between hobby and mental illness."It may be a fine line but I stepped over it a long time ago.:D

[seafire]

I was about to buy a better quality CDP, when I switched gears.
I went to a NOS DAC via USB, using pc with lossless FLAC and
ASIO4ALL to bypass Windows crap. The result was pretty good.
I'm watching for that killer DAC deal that I know is out there.

I then went back and installed FRED diodes in the power supplies
of two of my CDP's. I also changed out some 5332 chips in the AMC.
That resulted in some good gains in the sound.
The fast recovery diodes helped bass, while removing muting transistors
on the AMC output helped increase top end sound.
While jitter may be a problem, there's a lot of other places to get good
gains in sound. Most CDP's have a lot of other weak points on the power
supply and analog side to contend with. Of course, a good external
DAC would fix most of that. It's a never ending game. There's always
a weakest link.
Glad to see someone else has had good results with ASIO4ALL Very good software and same as used by many studios;)

[heiney9]

I thought everybody knew about ASIO4ALL when running a PC rig. Bypassing all the Windows processing is mandatory to do it properly. I guess I assumed wrongly.

[steveinaz]

I'm not sure about Benchmark's claim.

I noticed the same when trying to use my Panasonic BluRay, and my Denon 2910 as transports vs my CEC. The CEC won easily. It was just far smoother sounding with a deeper/wider soundstange--treble was less stringent.

[Fongolio]

I have read that some extremely high end music servers use solid state storage (no hard drive but instead more like ram memory). The theory is the less moving parts the less chance of clock induced jitter.

[Flash21]

I'm still trying to wrap my head around the fundamental idea that variations in timing of a binary code can affect the sound...this only seems to make sense if the timing of the analog music notes is not contained in the code itself, but is instead based on the timing of the code's arrival at the D/A converter...but keep in mind that I am very computer challenged, I am probably missing something fundamental you computer geeks know.

[GV#27]

When trying to recreate the original analog waveform with 1's and 0's timing errors result in the right data but at the wrong time.

[megasat16]

Thus creating phase shift and makes peaks instead of dibs?

Well, I guess one can reduce the clock jitter by multi-path DAC and ADC at both ends and transmit at higher synchronous clock rate and do some kind of hardware error checking. I mean we can absolutely transmit and receive data over single media at different frequency and encode and decode the data back to the original form at both ends. We can transit the data at least 4 times higher than sampling frequency and transmit it over the same media at 4 different channels using different frequencies (multiplex). We can also sneak in two extra channels for data correction (sort of like CRC) and master clock rate for synchronization and we can even piggyback the master clock signal for ultimate accuracy. We can receive all 4 different signal paths along with two extra channel at the other end and de-multiplex and compare against master clock rate. We can even introduce the data correct scheme in the transmitted data and checksum over the 4 different signal paths to make sure data integrity. The receiving end can do all the calculations to correct clock jitter and any momentary jitter caused by interference over the cable. I guess things like this cost a few bucks for computer (and data communication) hardware but no one even want to sell things like this for under a grand for audio. Well, it's already been implemented for all data communication equipments and digital transmission standards are set for Industry. Unfortunately for the Audio community, the standards are either rare or disputable due to everyone doing different things.

What the hell I am talking about? :D

Just use the Analog out from the CDP and forget all this crap I said above. :)

[Flash21]

When trying to recreate the original analog waveform with 1's and 0's timing errors result in the right data but at the wrong time.
That's pretty much what I am saying...apparently the time axis of the analog waveform is contained not in the code itself, but in when the code arrives at the D/A converter.

Which is probably an efficient way to do it, saving bandwidth. Nowdays though, bandwidth isn't the problem it used to be.

[seafire]

Thus creating phase shift and makes peaks instead of dibs?

Well, I guess one can reduce the clock jitter by multi-path DAC and ADC at both ends and transmit at higher synchronous clock rate and do some kind of hardware error checking. I mean we can absolutely transmit and receive data over single media at different frequency and encode and decode the data back to the original form at both ends. We can transit the data at least 4 times higher than sampling frequency and transmit it over the same media at 4 different channels using different frequencies (multiplex). We can also sneak in two extra channels for data correction (sort of like CRC) and master clock rate for synchronization and we can even piggyback the master clock signal for ultimate accuracy. We can receive all 4 different signal paths along with two extra channel at the other end and de-multiplex and compare against master clock rate. We can even introduce the data correct scheme in the transmitted data and checksum over the 4 different signal paths to make sure data integrity. The receiving end can do all the calculations to correct clock jitter and any momentary jitter caused by interference over the cable. I guess things like this cost a few bucks for computer (and data communication) hardware but no one even want to sell things like this for under a grand for audio. Well, it's already been implemented for all data communication equipments and digital transmission standards are set for Industry. Unfortunately for the Audio community, the standards are either rare or disputable due to everyone doing different things.

What the hell I am talking about? :D

Just use the Analog out from the CDP and forget all this crap I said above. :)
LOL that my friends about sums it up in a nutshell:D
That is why I am tempted with the German design as you can take any cd player and even a pc whith coaxial out and have near external dac quality.Problem is it's not that cheap and I think by now there must be some good external Dacs floating around with built in jitter correction:rolleyes:

[megasat16]

While Jitter is definitely a pain in the S and often over looked in the Audio Industry, this is a lot more of an issue for data comm equipments where switching 1 to 0 and 0 to 1 makes the whole data a complete garbage.

Anyhow, the problem with the Audio Industry is that there is very little set standards and protocols so a well design and good CDP with a good DAC section could cost 10K or 100 bucks. Likewise, any poorly designed CDP with so so DAC will sell for 100 bucks because they know they can sell it for that much and puts 90% profit in their pocket. It's much like what Cable to choose.

A well design CDP or any DVD player with a good DAC should take care of 99.99% of the synchronization problem. The other 0.01% is considered not enough to make a difference in sound quality at the other end. Of coz, one can always be extremely cautious about this and wanted to have something better. It's completely acceptable to me for someone to pursue the highest level of perfection one can obtain.

As always, a manufacturer can look everything under electron microscope and exaggerate any tiny correction they could make about it and overly built to accommodate such feature and charge 10 grands to those who don't mind paying for it. It's perfectly fine as long as there is the market and there is the manufacturer for those kinds of gear and I am happy they can afford these and not me. :)

[heiney9]

Here's a more down to earth explanation of jitter. I don't necessarily agree/disagree with what's said. But it is laid out in nice format and easy to understand conceptually. A good read if you are at all interested in understanding this phenomenon but don't have an EE degree ;)

http://www.audiocraftersguild.com/AandE/cd-jitter.pdf

H9

P.s. I know it's dated but the first couple pages are good explanations

[Flash21]

Thanks, reading that link now...


What this means is that any reasonable transport will deliver an identical data stream from any reasonable disc, regardless of how much green ink is around.
;) :D

[megasat16]

Thanks Brock! A Good Read For Any Audio Lover!

[GV#27]

Well, I guess one can reduce the clock jitter by multi-path ....

There does exist a format called I2S that allows for the transmission of the data and clock signals separately,not combined as in the SPDIF.Unfortunately only a few manufacturers adopted it so it never gained widespread appeal.

[W WALDECKER]

A dedicated clock power supply with an accurate clock is the way to go in a stand alone CDP

[NJPOLKER]

After a HARD week hunting and drinking, well not much hunting, I had the jitters and after a few drinks they were gone. A simple fix as far as I was concerned.