Just curious. The Oppo BDP-83 has now been out for about six months and the online mod businesses are already doing their thing(s). The 27MHz clock is the first item that is obvious to upgrade. Has any of you DIY'ers done this for themselves yet and what has been your experience in A) ease of fitting new clock and possible complications, and B) what did you observe as far as performance.
Over to you guys.
Joe R.
Over to you guys.
Joe R.
Just to add to above. Have anybody installed a Burson clock into the Oppo Blu-Ray? I believe they, Burson, recommend that two resistors forming a dividing network is required after the oscillator (3.3V) stepping down to 1.8V or lower (I have a Philips BDP service manual that says core voltage is 1.1V for MT8520 which I gather is basically the same chip used by Oppo).
Does anybody know what those resistor values are or have come up with other values and used successfully as well? This of course applies to clocks other than Burson's.
Joe R.
Does anybody know what those resistor values are or have come up with other values and used successfully as well? This of course applies to clocks other than Burson's.
Joe R.
carefully remove the 27m crystal , C194, C197 and R84.
the new clock signal i/p is the solder pad of the crystal that is closer to the mt8521 chip
Thanks for the reply. But have you then run the Blu-ray sampler disk via HDMI out? You will see that the picture is continuously chopping, like flick... flick... flick... etc.
Right now I am running two BDP-83 players here in the following way. The output of the oscillator sees a voltage divider network made up of 100R and 50R. Note that attenuates then clock signal by 3:1 - I don't remove R84, it's still there.
Note that this means I am running 1.1V logic and that the MT chip is likewise, nowhere near 3.3V. The players work just fine.
This is why I started this thread. I believe that Burson Audio's clock is installed the same way via a voltage divider after the clock. I don't have proof but if I am right then what value resistors are they using and are the also attenuating 3:1 as I am?
Hope there is somebody who can enlighten on this topic.
But thanks form your input. Maybe you should try what I have done. How is your HDMI output with full 1080p?
Cheers.
Joe R.
That certainly surprises me, you are feeding 5V to the TCXO or 3.3V?
Is there any domumentation that you have seen, especially on MT8520/MT8521 (Oppo uses OP8521G I believe) and what made you decide to use the Xtal pad closest to the chip as the XT_IN. I saw somebody posting a pic that shows he was using the pad furthest away. Are we just guessing or is there any actual docs that makes it certain?
Cheers.
Joe R.
So you are using something like this:
An externally hosted image should be here but it was not working when we last tested it.
I found documentation by Philips who uses a version of the same MediaTek chip in their Blu-Ray players, and it makes clear that the clock should 3.3V - I was sure that R84 should not be removed and yet I have seen others remove it too. You are right, the pad closest to chip/heatsink is Xtal_In and I have a 3.3V oscillator connected to that and R84 stays across Xtal_In and Xtal_Out. I am absolutely sure that this is the correct method and now backed up by documentation, albeit from an unlikely source.
And yes, it works just fine. So if there are others out there fitting clocks to the BDP-83, this should be of interest. But thanks arthur, you helped me to clarify things.
Cheers.
Joe R.
And yes, it works just fine. So if there are others out there fitting clocks to the BDP-83, this should be of interest. But thanks arthur, you helped me to clarify things.
Cheers.
Joe R.
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I have a stock BDP 83 and I'm curious what differences/improvements you guys are finding after the mod. Is it only to the audio or also to the PQ. I'm more interested in PQ improvements. Who's clock circuit are you guys using? Do you have a schematic of the 83? or of the whole clock circuit?
Thanks
Thanks
Does it matter if R84 is removed?
Perhaps you can get away with it but it it really ought not to be removed. But I do wonder if, in your case, when using 5V rather that the now confirmed correct 3.3V, that for some rason R84 needs to be removed. If you tried to put R84 back - not necessarily using the original SMD which was likely discarded, but a new one across the old Xtal pads - and it won't work properly with 5V, then scale the voltage down to 3.3V and it will work correctly with R84.
Does the oscillator you are using also work satisfactorily at 3.3V? Mostly HC04 chips do. I recommend this and R84 should be the way to do it.
I have a Sony S9000ES which uses a 3.3V oscillator. When somebody accidentally tried 5V clock, the player turned On and then Off within seconds. When it was reverted to 3.3V it worked properly. That the Oppo doesn't do likewise is just one of those things, but I repeat, it should still be 3.3V.
Also, re R84 or similar on other players, it should never be removed as it prevents potential "floating" problems. The R84 makes sure that Xtal_In and Xtal_Out are always at the same potential. That has to enhance stability.
Cheers.
Joe
I note that other upgraders like Burson clocks as they are inexpensive and no doubt is an all round improvement. We and Vacuum State uses our own and is known as Terra Firma Lite (internal PCB installation) and Terra Firma UberClock (external box with 75 Ohm feed into the player), but these are rather more expensive than Burson, but also, I hope you won't mind me saying this, the performance is on another planet.
Not sure if somebody has a schematic for the Burson but VSE and Custom Analogue Audio are not revealing theirs. Although I suspect that eventually other clock manufacturers will figure out what makes Terra Firma click in a way that others don't and will catch up? Until then we have the jump on them.
Here is the article that helps explain what TF is: Terra Firma
Here is the link to the Terra Firma upgraded Oppo BDP-83: JLTi BDP Oppo Player
Re improvement, mostly the audio side but some also claim to see a cleaner video picture. Certainly the TF improves ALL outputs that carry sound, analog outs, HDMI, RCA coaxial etc. anything that takes the audio out of the player.
Cheers.
Joe
Hello
Do using 74xxxx chips for a clock can do more jitters ?
Have you try the LC-clock schematic ?
Thank
Bye
Gaetan
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Dear Joe,
Thanks for sharing all this information.
Just to be clear. I can connect a Tentlabs 3.3 output clock direct to the solder pad closed to the heat-sink and only remove C194, C197. The player works fine with this?
Thank you in advance.
With kind regards,
Bas
Exactly.
Where the idea that R84 should have been removed I'd like to know. This is across XtTal In and Xtal Out and always should never be removed. If it needs removal it could be an indication that the wrong 'input' has been used.
I came across another site where somebody had posted a picture where the two caps and R84 had been removed and the photo clearly showed that the clock signal was soldered to the pad furthest away from the chip. We now know this was wrong even if it did work, sort of (except HDMI on 1080p video was flickering). But to may that work R84 had to be removed. That bothered me (and the flickering 1080p) and in the end was proved right. Leave it in there and solder the clock signal to the pad closest to the chip.
Cheers.
Joe
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