[tim3320070]

From what I have read, jitter under about 200 is inaudible- maybe more maybe less but it seems people shooting for under 50 with jitter is not necessary. This is what I read from a couple of different sources here and elsewhere.
I feel it's overemphasized to garner sales.

 

[tosehee]

Quote:

Originally Posted by gevorg /img/forum/go_quote.gif In theory you're right, but what if DSP-1's jitter is below audible levels? Sooner or later that threshold will be reached, if not already.

Refer to Peete's comment about CD7. He uses Re1 and CD7 brings a pretty good upgrade. If the DSP1 inside Re1 is so great, there shouldn't be any difference. So, I doubt DSP-1 is really that great in terms of fighting the jitter.

 

[tosehee]

Quote:

Originally Posted by tim3320070 /img/forum/go_quote.gif From what I have read, jitter under about 200 is inaudible- maybe more maybe less but it seems people shooting for under 50 with jitter is not necessary. This is what I read from a couple of different sources here and elsewhere. I feel it's overemphasized to garner sales.

Depends on who answers your question.

Linuxworks believes that there is no difference at all and most recent DACs should have a very good jitter protection. In short, you shouldn't have any difference whether you use $30 SC with optical out or $200+ SCs.

On the other hand, there are handful of ppl who thinks exactly opposite. So, I'd say research more/test yourself/believe your ear.

Regards

 

[IPodPJ]

It is not just about jitter. Jitter has been tamed to such an extent these days that it is not much of an issue anymore. Something closely related to it, clock phase noise, is more of a problem. Also, read about PLL, or Phase-locked loop, which is a control system that generates stable frequencies.

Take a look at these Wiki pages for info on the subject:

Phase noise - Wikipedia, the free encyclopedia

Phase-locked loop - Wikipedia, the free encyclopedia

And let's not discount signal reflections in cables, whether optical or electrical. I've personally found that a cheap digital coax cable of 18 feet in length outperforms cheap or pricey cables that are 3 to 6 feet in length.

 

[tosehee]

Phase Noise is caused by the jitter, but you said that jitter is pretty much non-issue these days. So why is phase noise is an issue when the root is already addressed/fixed?

About phase-locked loop, how is this related jitters/noise/audio?

 

[IPodPJ]

Kingwa could explain it to you (hopefully) a lot better than I could. I have a hard time understanding much of the technical stuff myself, but it's been explained to me a few times with people who have been in the hobby a lot longer than myself and who have engineering knowledge that I don't.

I can tell you that without a doubt, when you improve your transport you will be extremely happy with the difference you will hear. I could give you all the usual audiophile babble like better separation of instruments, wider soundstage, more spatial imaging (which it does) but you need to quantify the difference with your own ears. To me, every step has been an increase in quality.

First came my Creative Labs soundcard.
Then my ESI Juli@.
Then my Squeezebox Duet.
Then I added the CIAudio VDC9.0 power supply to the Duet
Then I added custom cables to the power supply to connect to the Duet.
Now I have a Transporter (which has been the most impressive of all by quite a bit.)
Hopefully soon I will mod the Transporter with an even better clock and digital output board.

 

[tosehee]

PJ.

No offense, but what you said is a subjective listening experience. It's something that no one but you can dispute. It has no scientific bearing on why it improves the sound that you hear.

I'd love to audition and experience the same myself, so I know what you really refer to. But, there is nobody in my local area where I can audition with different transports myself.

 

[IPodPJ]

Yes, the equipment I've been through and the order I've upgraded was because of subjective preference, obviously. But there are reasons why every piece of equipment down the line I chose will perform better than the one before it, and I could go through each one and explain it to the best of my ability (with the exception of the added cables, since I have no way to quantify why they sound better than the stock one).

And isn't the reason you prefer your current equipment because of subjective preference? I would assume it sounds better than whatever you had, otherwise you wouldn't have kept it -- unless you're one of those people who thinks that newer and more expensive always equals better, which I hope you're not.

Perhaps you can ask around and find someone to loan you a good transport

 

[tosehee]

Of course, PJ.

The subjective experience is why we are opting to upgrade. However, you can't really use that as a proof/explanation as to why something is better than the others.

The objective test that can be tested and verified repeatedly is what I am asking. If not, maybe provide some scientific explanation as to why upgrading the transport (the question in here) improves over time when your DAC remains the same.

In short, you said you hear the improvements from

Juli -> SB -> Transport.

the DSP-1 inside RE1 supposed to make the jitter a non-issue. The noise issue that you referred in the another thread is 'caused' by the jitter, which should be non-issue due to DSP-1.

So, in theory, there is no difference whether you use Juli/SB/Transport as long as your RE1 is in the chain.

What am I missing here?

 

[CapQ]

woooow it seems that get more functions than Bel canto USB/SPDIF converter

 

[AtomikPi]

Quote:

Originally Posted by tim3320070 /img/forum/go_quote.gif From what I have read, jitter under about 200 is inaudible- maybe more maybe less but it seems people shooting for under 50 with jitter is not necessary. This is what I read from a couple of different sources here and elsewhere. I feel it's overemphasized to garner sales.

I'm not sure what units your numbers are in. In nanoseconds, it takes around 50-100 to defeat the PLL and be audible (based on listening tests - I don't have a link right now). This means it's not really much of an issue because nearly all transports (even a $100 soundcard) provide a max of 4-5 ns jitter and generally well under 1 ns. Stereophile did an article and the highest jitter source they could find was some studio product at 4ns with the lowest being .04 ns from the CEC transport. The Oppo players are also very competitive considering their prices.

 

[tim3320070]

I'm sure my numbers/units are not remembered correctly, my point is that I feel jitter is not a big issue, and is overplayed, as I understand it (in the audiophile world of splitting hairs).
So you are saying what I meant, just said more informed.

 

[Pricklely Peete]

tosehee how well the laser extracts the 1 and 0's off the medium is another aspect of digital that no one thinks about or forgets about. If the 1 and 0's are error riddled from the laser mech reading them the result will be really awful. The Transport it's servo system...it's power supplies the dampening of the chassis all contribute to better sound quality which in turn = a more accurate extraction AND a more analog like presentation. Less digital error in turn reduces jitter although jitter cannot be completely eliminated just like wow and flutter cannot be completely eliminated from a tape deck or turntable. But they can be minimalized to a degree which makes them somewhat inaudible (debatable at times it would seem)

The error correction circuitry can only do so much. If you get too many "guesses" things go south pretty quickly. Hard treble, muddy ill defined bass, poor imaging, a real lack of dynamic slam, 2D presentation.

There is more to a CDP or Transport than just it's jitter rejection, obviously but that seems to dominate conversations and I think it's only one aspect of many with digital that needs to be addressed. Think of it as turntable with a laser instead of a cartridge. It's subject to the same mechanical forces a turntable is subject to meaning the same tweaks you use on a turntable to reduce vibration, isolation etc benefit the CDP/Transport as well. Disc clamping/stabilization etc...

When you truly think about it a CDP is an analog device in every respect except the way it reads the information from the medium. The rest is all mechanical/analog...that goes for a normal hard drive as well. It's a analog device reading magnetic pulses off a disk with a arm and head.....the storage of the info is different but the same as tape in a way. Subject to wear and vibration,error etc just like the CDP and Turntable. Introduce EMI/RFI...vibration etc and the result is less than ideal. No different for a CDP...

I hope that helped some members think of the entire box instead of just one part.

Here is why the CD7 creams everything else I have.......

The CD7 weighs nearly 35 lbs....it's a heavy beast that has shielded servo circuits and a shielded drive with additional dampening added onto to both critical parts. Look at the pics on Kingwa's website. These copper boxes have that heavy dampening material glued on. The rest of the Transport is just as well thought out. The error correction circuitry, the clock, the digital out sections are all well thought out custom pieces that go beyond the normal config. There is parts of this Transport that are not used on any other in the world. I'm damn glad Kingwa built this machine. It took the RE1 to another level without a doubt.

It's so much better than my comp T or other traditional transports it's tough to put into words exactly. I'd say it's the difference between a Class B device and a Class A or even A+ territory.

Peete.

 

[Tachikoma]

Quote:

Originally Posted by AtomikPi /img/forum/go_quote.gif I'm not sure what units your numbers are in. In nanoseconds, it takes around 50-100 to defeat the PLL and be audible (based on listening tests - I don't have a link right now). This means it's not really much of an issue because nearly all transports (even a $100 soundcard) provide a max of 4-5 ns jitter and generally well under 1 ns. Stereophile did an article and the highest jitter source they could find was some studio product at 4ns with the lowest being .04 ns from the CEC transport. The Oppo players are also very competitive considering their prices.

4-5 ns?????????? I'll be surprised if your DAC could even lock on to that signal. (Mine won't work with transports based on the Philips UDA1321, which produces about 1ns of jitter.)

.04 ns is the equivalent of 40 picoseconds, which isn't bad at all.

Edit: Thought it was exclusively a USB-SPDIF, sorry :x But still, does Kingwa have any measurements? ie: jitter measurements with and without the REF3 in the signal path.

Reading this just makes me cringe:
http://www.head-fi.org/forums/f149/s...verter-427470/ - $999 for THAT? A USB line is a GREAT 5V source isn't it?

 

[XXII]

Quote:

Originally Posted by Tachikoma /img/forum/go_quote.gif 4-5 ns?????????? I'll be surprised if your DAC could even lock on to that signal. (Mine won't work with transports based on the Philips UDA1321, which produces about 1ns of jitter.) .04 ns is the equivalent of 40 picoseconds, which isn't bad at all. Edit: Thought it was exclusively a USB-SPDIF, sorry :x But still, does Kingwa have any measurements? ie: jitter measurements with and without the REF3 in the signal path. Reading this just makes me cringe: http://www.head-fi.org/forums/f149/s...verter-427470/ - $999 for THAT? A USB line is a GREAT 5V source isn't it?

Here are some measurements for the DSP-1 (in chinese):
н¨ÍøÒ³ 1

The Ref 3 uses the DSP-3. I'm not sure if this is better or worse.