How can you hear jitter

The line transmitter device converts binary data to electrical levels. The line receiver device converts electrical levels back to a binary sequence. And the clock reference moments are the points where the voltage level gets higher in the threshold.

The line transmitter generates a signal close to the square. Thus clock reference moments, detecting in the line receiver, may be offset from their initial time position time deviation at the picture.

Below we will consider where the jitter penetrates into the audio system. Jitter is a non-linear distortion. To measure jitter need put pure sine to the input of a known system. Jitter products artifacts and noise depends on the input signal.

To check the dependency we can take a spectrum analysis of different input signal level and frequencies. The picture is not a real spectrum. It is only an illustration for better understanding.

Measurements 2 and 3 allow us to identify separate errors within individual system parts. Jitter is a deviation time between samples. Delay is shifting of a full signal waveform but keeping time distance between samples. Latency is a delay for processing inside an audio device read below about a FIFO buffer. Above we considered, that clock deviation is an effect of digital signal distortions.

Clock generators have electronic elements, that define the frequency and its deviation. Changing the power DC voltage can cause frequency deviations of the clock generator. Power supply units can generate noise into electrical lines. This noise can modulate the generated clock impulses. The modified clock signal causes the time deviation see the picture. Noise, that impact on the digital audio signal line, penetrates from electrical circuits and the air.

Needless to say, I take much of the claimed auditory observations with a grain of salt. Many theoretical differences that justify large expenditures do not conform with auditory reality.

From a telelogical perspective, our auditory system must be generalizer, otherwise it wouldn't serve us well. So of course explanations of the sound of jitter will be vague.

After all, how many angels can dance on the head of a pin? Dgarretson: great example of a controlled experiment. I wonder how much the improved clock circuitry reduced radiated emmisions, reduced injected noise into the ground planes, vs the degree it reduced actual clock jitter. I'll always have a hard time understanding why nanoseconds of clock skew difference matter in most modern cd digital receiver front ends.

I mean the digital data is clocked off the substrate then buffered fifo in the main cd dsp; inside this dsp, a new clock is generated and sent across the interface to the DAC. This buffer is pretty much crucial to good cdp function. I don't understand how jitter, as long as the set up and hold times of the actual registers are met, can be any kind of problem.

I have never done a clock mod; do they instruct the modder to cut the typical crystal clock osc and insert the new clock signal there? Another key feature to modern cd dsp chips is that the actual word or frame is entirely jitter free.

Perhaps one could argue if the jitter is so horribly poor that individual bits are mis-sampled as they are clocked into the DSP, then the overall value of the word is off , but that would have be a seriously poor design. Personally too much marketing emphasis is placed on jitter, I feel. The standard approach by all high end cd player designs is to implement an off the shelf DSP device the thing that sits very close to the spinning disc and is responsible for servo, and data sampling, as well as microcontroller interface and an off the shelf DAC.

Some play games intermediate stages to decouple clocks and reduce skew, but in the end it's really just designing with building blocks that have existed since the 80s. Jitter is one aspect to all this but I think its contribution to the overall distortion spectrum is very miniscule w. I don't doubt that anyone hears a difference from a mod, but it's hard to distinguish between REAL differences and perceived ones based on expectations after all the time effort and money went into it there better be a difference right?!

Anyway these are my personal experiences. It's all good fun. Large expenditures do NOT conform with auditory reality. I agree again. So in view of Sony's set-up that theoretically isolates master clock from digital noise, I am inclined to consider that audible improvement may be largely due to accuracy of the replacement clock. Whether this is due to reduced jitter or to reduction of other noise I cannot say.

But I have no doubt that improvements in the digital domain other than clock are audible as well. Esoteric sells an optional out-board clock for its top player that's accurate to a half part per billion; magazine reviewers claimed to hear a difference.

I know a fellow in Japan who makes similar claims using an external pro signal generator to clock his player. All this might sound like an exercise in diminishing returns but my ears tell me otherwise. Shadorne, I know what you mean. There is a point after which it really is just a silly excess. I've had just as much emotional involvement with my music through the years of upgrades, as I do with my car system. ALl the upgrades have never changed my response to my favorite music.

I would argue that Sure there is something to sitting in the sweet spot, in your space but that's all just initial conditions to the hardware equation. But it's all good, as I clearly prefer this to most other money sucking fascinations.

Shadorne, Feb. At the opposite extreme there are finally several less-than-superlative reviews of megabuck products e. MP3 sounds great doing an 8 minute mile on the treadmill. First off wantd to congratulate soem of our members here for their incisive and descriptive talents.

It has been propven without a doubt that Jitter is very perjudicial to our music, there was a test done in which a panel of well versed and auditioned audiophile and musicians listened for a litle while to a CD of first cut recording direct to avoid missinterpretaions or wrong intent then to listen to the same part of music but the th generation of recorded music on CD as well. Same data, same bits no data error, same thing, what was the differnece between those two recordings?

So even though MP-3 is sonically inferior to 16 Bits also 16 bits are very rudimentary when compared to 24 bits 96 Khz or KHz material. That is my 2 cents here. Also when evaluating new components or speakers this still is the batter way to go. God Bless! Gonzalo, In Digital copy generations, there is no more Jitter in the 2nd generation than there is in the th generation, since every time you repeat the loop you go back to the hard disc and all the Jitter that the laser added is again gone.

Other than that, you can send Digital files to CD's, Flash Drives, up to the Mars Rovers and back again, and then burn your CD and it will have the same amount of Jitter if burned under the same circumstances as your first copy. These various reasons include the substrate material, reflections, focussing, vibrational issues, etc.

Liudas, True. Shardorne, yes, you are right. Noise jitter is when the ticks of the clock are off by a random length of time. That means x is a random number. I used a normally distributed random number, which is what we are more likely to have in the real world. Periodic jitter is when x oscillates in time. This jitter can be caused by the 60 Hz or its harmonics from your power supply leaking into your clock generation circuitry.

Every circuit is unique, so in the real world periodic jitter can come in different frequencies. However, for the sake of simplicity, in this experiment, I used 60Hz periodic jitter. I ran the simulation on There are seven versions of each sample.

Three have periodic jitter, three have random jitter, and one is the original - untouched. As you scroll down you can listen to them and make your best guess of which is which. Then you can click the sample's title i. Before you move on, here is something to keep in mind. The clock interval of a Jitter is expressed in RMS microseconds.

Your browser does not support the audio element. Let's see what the spectrum of the 1kHz tone looks like after jitter is added 1kHz tone with no jitter added. Now an excerpt from a favorite artist of mine, Vanish Ark. We are going to do something different with this sample. I've had my moments where I preferred an analog version over the digital version usually if the digital version is a bad remaster but it's rare and even rarer a noisier version of something old school game consoles that didn't have the greatest of sound systems , usually.

Not going to lie there. Last Edit : by Chibisteven. Thanks for all your responses, everybody, and thanks for the jitter soundclips, Arnie. You answered my question of "how does jitter sound? I thought I made it clear in my original post, but apparently not: To the best of my knowledge he has never owned a turntable.

He's not a vinyl freak. He's a hi-fi manufacturer, and he's considering buying a turntable purely for his showroom, as many potential clients could come in and ask for a demonstration with a turntable you know, analogue is always better - we all know that. At one point he said he wouldn't want to switch to vinyl as it was too troublesome cleaning, the price, etc. As for what types of music he listens to, then it's varied, but mostly "nice" modern recordings Diana Krall and the like and classical music.

Although he might listen to a few compressed albums like Daft Punk here and there, it doesn't seem common for him. And yes, I think he might have been influenced by the audiophile community who's nowadays constantly talking about jitter. Did anybody read the response I got on Dan Lavry's forum? The link is in my original post. I know that he's somewhat in the "other" camp audiophile camp , although he seems very, very scientifically minded.