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Hi Guys.Just stumbled across this mod site on the web. Check out their 963SA mod package!! It is certainly different from what is normally offered, with piggyback DAC configuration like Accuphase and upgraded upsampler IC and crystal. Not to mention a dedicated toriodal linear power supply for analog stage. Heck even includes a mod on the pscan board for video!! Seems to be much value for money!!
Check it out guys.
www.effectiveaudiomod.com
Zhi yuan
Follow Ups:
to them, with NO ADDRESS, NO LOCATION a to what country they are in, is an invitationto be ripped off. This may be the most honest business organization in Swaziland, but Buyer Beware.
Hi.I personally has my player done by him. He is based in Singapore.
I am sure it is a oversight by him. Maybe his website is just not completed, as he has just started his website. I'll inform him to update with your comments.
I don't think anyone who is thinking of ripping you off can post such techical photos.
Regards.
Tze Guan
There's no way I'm getting mods done in Singapore from U.S. There are Plenty of talented (and proven) modders here in the States...
I agree. Nor would I send my player to Swaziland!
"Picture shows triple DAC configuration (2 extra on top of the original)."I'm sure there's a good reason for doing this ... but it isn't obvious to me.
Stephen
Doggy style :-) Sorry, just couldn't resist..:-))Best,
AP
Read this
This method is really for improvement for current-out DACs.It is made popular by monarchy audio, in their stand-a-lone DACs, as well as Diy guys for non-oversampling DACs using philips DACs.
From what I know this is what acuphase used in their SACD players, however, their implementation is board mounted.
The benefits of this is improved output current drive and resolution by averaging errors, though I can't confirm this.
For AD1955 DAC, it is really difficult to do this as the legs of the IC is really very fine (0.5mm pitch).
Regards.
Tze Guan
the clock freq ????This web said the 27M is used for SACD, CD and DVD, While the 33.8M is used for the 1895 when upsampling at 192K.
This is some how contradict to what I gather from other web site in modding this 963. Can someone confirm this ? I thought the 33.8 is for the SACD !!! Expert, please comment. Thanks.
Alan
From the site: "963SA actually uses 3 clocks for audio:24.576Mhz for CD Upsampling (96Khz and 192Khz operations) in the analog board.
27Mhz thru MK2703 PLL IC for SACD and CD and DVD in the motherboard.
33.8688Mhz is only used for processing clock for 192Khz operation for AD1895A.
Why is the 33.8688Mhz clock not used for SACD and CD?Because AD1955 DAC has a problem with this master clock frequency for SACD and CD playback!!!!
Let’s just say that the engineers at Philips were told of this only at the last moment"
> > The 33.8688M IS USED for SACD and PCM and is also PLL-ed to the 27M video clock. Actually the 27M video clock is derived from the 33.8688M. Of course, the 33.8688M is divided by 2 so the actual DAC clock for normal PCM is 16,9344M.The 24,576M clock is used ONLY for upsampling and as a master clock for the 192K.
Regards,
Alex
What you are saying is the original intention of the design.In the 1st production run, they used this architecture,
33.8688Mhz ---> frequency divider----> 16.9344Mhz-----> motherboard-----> ICS612 PLL----> 27Mhz----> ICS MK2703 PLL ------> 11.28Mhz for CD/SACD.
However, this creates a lot of jitter due to audio clock for SACD/CD having to be derived from 2 PLL. Hence they change the architecture to:
27Mhz oscillator on the monoboard -----> ICS MK2703 PLL----> 11.28Mhz for CD/SACD.
and did not used the 33.8688Mhz other than for AD1955 192Khz processing (as AD1955 spec a processor clock of > 30Mhz for 192Khz processing.)
My information is correct as it is from the designer of 963SA himself!!
Regards.
Tze Guan
...You might be right that they changed the design. I haven't seen it though. My Service Manual shows the "first" architecture. If they changed to 27M clock and derived the PCM/SACD clock from it, it is clever but that will result in totally removing the 33,8688M clock from the circuit because you don't need it anymore.AD1955/56 calls for 30M clock MAX. The 24,576M clock is the one and ONLY used for upsampling. It provides 256 Fs for 96K and 128 Fs for 192K. Why you need that since AD1955/56 are asynchronous? It is because in 192K mode AD1955/56 CAN NOT operate in Master mode, so you will need the 24,576M clock to provide the 128 Fs clock for the DAC.
Say hello to the 963SA designer from me and tell him that the DAC was a bad choice...:-)
Regards,
Alex
The 33.8688Mhz is really used by the sample rate converter AD1895A as system/processor clock for processing the 44.1Khz I2S data from the motherboard to the AV Board.Initially, they really wanted to run the DAC for SACD/non-upsampled CD in 16.9344Mhz, off the 33.8688Mhz/2, so that they can get a good audio clock and a processor clock for the sample rate converter AD1895A.
However, AD1955 has a problem with running off the 16.9344Mhz for SACD and CD non-upsampled as its internal PLL has problems locking to this (16.9344Mhz is 384FS. AD1955 has to convert this to 256FS, its internal clock).
Also if AD1955 is a bad choice, what would you recommend?
Regards.
Tze Guan
....And again the 33,8688M is NOT USED to clock the SRC (AD1895). It is used for 44.1k PCM and DSD.It looks like you're not following what I am saying or you just don't want to. The 24,576M clocks the AD1895 SRC so whatever you are saying and what is posted on your friend's site is incorrect.
I would personally go for Crystal and even some Burr-Brown DACs before the AD1955. It's just me!
Regards,
Alex
It specifically says that if your masterclock to the sample rate converter is less than 30Mhz, you can only operate up to 96Khz upsampling.For 192Khz sample conversion, the only mode supported is the slave mode, and you need a masterclock > 30Mhz to do that.
In 963SA, the 24.576Mhz clock is used for
1. 96Khz upsampling master clock for AD1895sample rate convertor in Master mode.
2. Bit clock and LRCK generation in 192Khz mode (thru the syncronous counter IC, LVC161 I think.)
The 33.8688Mhz then is used as master clock for 192Khz mode only for AD1895A as it needs to operate in Slave mode and hence needs a master clock greater than 30Mhz for this.
In any case I have already measured the master clock pin of the AD1896A (mine is modded) of my 963SA in both 96Khz and 192Khz mode. I am correct.
For the ADI DACs, you are right about it though. The designer reports that it is so hard to sound-tune this IC especially with low budget given to him that for next generation players they would revert to crystal DACs, which is also lower in cost as they don't need expensive opamps for current-voltage conversion, being a voltage out DAC.
Regards.
Why did the modder stick to op-amps for the analog stage ?
Wouldn't it be better to use a discrete output stage.
I suppose almost anybody would agree that this would lead to better results. (?)
....The clock CAN NOT be more than 30M. Since the AD1895/96 CAN NOT provide master clock in 192K mode (because it MUST work in "slave mode"), the Data Sheet calls for additional (optional) 24,567M clock to provide MCLK and LRCLK (divided) for the DAC. That is why the 963SA sounds worse in 192/24 mode. It is because the AD1985 switches to "slave mode" and the MCLK and LRCLK are provided by dividing the 24,567M clock.I am not sure how to be more clear with you!? 33,8688 CAN NOT clock 192K as in slave mode as the AD1895/96 are SYNCHROUNOUS to the MCLK not asynchronous. You do the math, 33,8688 can not be divided by 128 in order to clock 192K.
128 x 192 is 24,576 it's THAT SIMPLE!
This is my last post here on this subject, but I highly recommend that you update your friend's site with the RIGHT information.
Regards,
Alex
Alex, despite his sometimes loose interpretation of the forum rules regarding advertising and self-promotion, was at least never outright deceptive. This "customer" should get lost.
.
It really is fun to read, although I don't have a clue what any of it means or doesn't mean. Kind of like when the service guy says your muffler bearings are worn out and you're going to need an all new exhaust system.
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