clock upgrade for cd/dvd players

[shallenn]

i came across this tweek for cd/dvd player. can someone check it out or tell me anything about the pros and cons to going further with this possable upgrade? thanks, shallenn check it out------------------------------------------------------ http://www.audiocom-uk.com/superclock.shtml

[hifiZen]

These clock upgrades are quite popular, and there is definitely some merit to reducing the jitter produced by the ****-poor clocks typically found in consumer gear. However, I would never spend an absurd 175 pounds on one!

As a DIYer, I would at least attempt something on my own. There is an excellent book on crystal oscillators (though you may experience the same difficulty locating it as i have): Crystal Oscillator Circuits by Robert J. Matthys, ISBN 0471874019.

Since finding this book, I've been toying with the Meacham bridge circuit, which appears to be the best of the lot. Perhaps some more modern circuits would outperform it, I don't know. Anyhow, I've only managed a few initial prototypes, and havn't yet been able to measure the jitter...

Anyone know how to measure jitter without expensive equipment???

Anyway, if you don't want to try building your own oscillator from scratch, you can buy a canned oscillator. Valpey-Fischer supplies very low jitter clocks. Add a good power regulator and a decent buffer chip, and bingo! ...you've got yourself a module just as good as this expensive kit.

[hifiZen]

oh yeah, of course you void your warranty if you go ahead and install one of these, and you'll also need to know where to tap the power for your clock, and where to remove the stock crystal and insert yours. Finally, you'll also want to verify that you're supplying the correct logic levels to the chip... these days, a lot of consumer equipment is using 3.3V ICs.

[ALW]

I've no experience of clock upgrades to a DVD player, but did fit one into a Marantz CD63 KI Sig and it was a truly huge massive improvement.

Another colleague fitted one to an old Meridian CDP and the results were just as good.

Jitter is one of the most fundamental issues to tackle in digital audio, it doesn't just decrease resolution, but generates non-musical spurious signals that are particularly horrid to the ear (i.e. they have no correlation to the audio signal).

Some manufacturers have stated that jitter of just 1-2 psec is audible.

I used a clock from Danish company LCAudio, which is considerably cheaper than the Audiocom or Trichord products, whilst offering almost identical performance.

There is a new version out called LClock XO2 (I used the LClock XO in the Marantz) that is a little more expensive but it's worth every single penny in my book.

A colleague is about to try one of these in an entry-level Naim CDP, the results will be interesting!

Andy.

[ALW]

LCAudio can be found at: -

http://www.lcaudio.com

[shallenn]

thanks for the info guys ill check into it more. i didnt know if an upgrade would give results that would be obvious. im always looking for a way to improve on what i got!!shallenn

[weeghel]

http://ariel.club.tip.nl/

Please check out this page, andlook for the cd player upgrade. Contact Guido Tent to ask for prices on the pcb boards he has just developed for this XO-Clock

[ALW]

Looks cheap - which makes it have an immediate appeal to me

Andy.

[hifi]

47E ?? what the hell is that???....shouldnt it be 47R as in 47 ohms? (check the diy clock schematic)

/micke

[cinglong]

TO hifi ZEN

whare to buy the book you say??
I live in R.O.C,so it hard to find it
and can you add PLL and reclock into the DAC?
I want to try it
thanks

[Edited by cinglong on 09-09-2001 at 09:05 AM]