Ric, see on your website that you have done the '103 - and just confirm as you said earlier on the '95 thread, this is 27MHz that was clocked properly.
Did you read re Coris' experiments with 25MHz and even upping to 50MHz (see #116 above "I just remember now an experiment I've done with this 25Mhz clock. I've used an 50Mhz one in that place. Nothing worked, except reading/playing files from USB interface. Of course I've got access to user interface. It were so exceptional video and audio out of the player, but were not possible to get access to transport and SATA)". That does not seem to tally with Jason? It's very odd, but the evidence still strongly point to 25MHz was correct. But hopefully no confusion this time and it being 27MHz for 103/105.
Cheers, Joe R.
Did you read re Coris' experiments with 25MHz and even upping to 50MHz (see #116 above "I just remember now an experiment I've done with this 25Mhz clock. I've used an 50Mhz one in that place. Nothing worked, except reading/playing files from USB interface. Of course I've got access to user interface. It were so exceptional video and audio out of the player, but were not possible to get access to transport and SATA)". That does not seem to tally with Jason? It's very odd, but the evidence still strongly point to 25MHz was correct. But hopefully no confusion this time and it being 27MHz for 103/105.
Cheers, Joe R.
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Coris:
You earlier said you had an ESS 9018 datasheet or application note. Can you post it here or PM with details? I'm not talking about the 2-page product sheet which is everywhere on the web.
Thanks,
David
PS
You can email it to me at david.musoke@yahoo.com if you have it.
You earlier said you had an ESS 9018 datasheet or application note. Can you post it here or PM with details? I'm not talking about the 2-page product sheet which is everywhere on the web.
Thanks,
David
PS
You can email it to me at david.musoke@yahoo.com if you have it.
Can you or Coris confirm my impression, reading between the lines, that Oppo has left left DC on the outputs, as DC bias to be seen by those caps? That may not be a bad idea as caps generally do better with some DC bias. But, in which case you have to find a way to remove the DC offset and you can't just get rid of the caps, as some seem to have suggested.
My own solution will be the same as the '95 which is DC coupled. The question is whether to sacrifice the headphone amp - I can disable all the I/V ICs, I can run 4x paralleled using jumpers. As these will each see a common 3R3 to ground-plane near DAC (reference point where things cancel), picking up anything stray has to be about as minimal as it gets. I will get same performance as '95 I suspect.
Still would like further confirmation that we are definitely back to 27MHz as was the usual standard in the past with Mediatek/Oppo.
I may possible get my first '105 this coming week.
Cheers, Joe R.
And the Oppo 95? Still insist it wasn't 25MHz?
If only Oppo would actually do what many others do, make a service manual available. But as I have experienced many times, certain (not all) American companies have a certain paranoia that, for example, the Japanese don't have with their products. Have worked for Panasonic, JVC etc, only to happy to... oh well.
Are you aware that when we bought parts from certain companies here in Australia, we had to sign a piece of paper every time they handed over the Invoice, that these components (transistors, ICs etc) were not to be put into products that would be sent to the US. Yep, they were American owned suppliers. It was a joke. And it was ignored. But then again, "free market" is an oxymoron.
Cheers, Joe R.
Every DVD, Blue Ray or Universal player that I have ever seen uses a 27 meg clock as the main clock.....every one. So, somehow this Mediatek chip is different? Audiocom did not look underneath the board and assumed the clock they saw on the top was the "master clock". I am glad they and all of us "sheep followers" assumed wrong because upgrading this "wrong clock" makes discs sound better. But if you want to see/hear what changing the "main clock" does, then you will have to change the 27meg clock underneath the board. Please try this and report back, if you want. I have no interest currently, too dang hard to get to and to expensive to change two clocks on the Mediatek and another one on the DAC.
The "three clock" thang I see on the 95 thread looks like it is using one power supply to power all three clocks. If this is true then this is really bad. Each clock will then "dirty" each other. Every clock needs a super, low impedance, low noise separate regulator to completely isolate each one from each other and for best performance.
A schematic in a service manual will not necessarily describe what each clock is for....you would see clock 1 and clock 2.....but not what function they are for. If you really want to know something about the Oppo then just email Jason at Oppo to get the correct info.
The "three clock" thang I see on the 95 thread looks like it is using one power supply to power all three clocks. If this is true then this is really bad. Each clock will then "dirty" each other. Every clock needs a super, low impedance, low noise separate regulator to completely isolate each one from each other and for best performance.
A schematic in a service manual will not necessarily describe what each clock is for....you would see clock 1 and clock 2.....but not what function they are for. If you really want to know something about the Oppo then just email Jason at Oppo to get the correct info.
At least Mediatek going back to a single 27MHz Clock in '105 will lead to no confusion. Yet it still does not answer the question why every person who fitted a 25MHz Clock to '95 heard more than a minor improvement on both disks and file playback, particularly the Oppo BDP-93 - and I did quite a few of those.
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Sorry to be delayed with the confirmation/information about the main clock in 105. Yet I have not the possibilities to get in to my 105 to see what is there... My player still be in its box, waiting for my attention...
Changing the "main 25Mhz" clock in the 95 bring huge improvements to both video and audio stages. This clock is not the wrong one to be improved! If is the main or not for Cmedia chip it still yet to be seen. For sure I will take a close look on this soon.
As I wrote earlier, I suppose the using of separation caps on the output of the 105 model is meant to fix the offset which it can occur at those outputs, because of control difficulties in the production process. If one player may have 10mV offset, another one may have 20mV or more. This is normal in an production process when the (cheap) passive or active components are not perfect matched. This problem it were not for the 95 model... It seems to me that Oppo get down in the quality (and price) for the components in the new model, to lower in the general production price for the player.
No mater the caps quality used for separation, the degradation of the signal is a fact. This is not acceptable in a prof and modern design.
Changing the "main 25Mhz" clock in the 95 bring huge improvements to both video and audio stages. This clock is not the wrong one to be improved! If is the main or not for Cmedia chip it still yet to be seen. For sure I will take a close look on this soon.
As I wrote earlier, I suppose the using of separation caps on the output of the 105 model is meant to fix the offset which it can occur at those outputs, because of control difficulties in the production process. If one player may have 10mV offset, another one may have 20mV or more. This is normal in an production process when the (cheap) passive or active components are not perfect matched. This problem it were not for the 95 model... It seems to me that Oppo get down in the quality (and price) for the components in the new model, to lower in the general production price for the player.
No mater the caps quality used for separation, the degradation of the signal is a fact. This is not acceptable in a prof and modern design.
Tell Ric that.
I have just used a 50MHz SAW Oscillator via 4040 chip to reduce 2:1 = 25MHz.
It is awesome!
And I hate the word awesome.
So Coris, want to try SAW on the 25MHz - trust me, you will like it.
If you can't use SAW on the '105 into the Mediatek chip, then I expect the '95 will remain superior for audio.
Unless somebody makes a 27MHz SAW, or we find somebody who will supply.
Cheers, Joe R.
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Why do you need to be so righteous? I said changing the 25 meg clock makes a noticeable sonic difference (this is the very clock I change). What I also said was that it was not the main audio clock. None of you have changed the 27 meg clock so you do not know what it will bring. Please upgrade that clock and tell us what it brings instead of recycling your ego.
I agree that the 27Mhz clock may be improved to compare the results obtained in changing the 25Mhz one. This for 95 model. I think I will do it. Have to find an 27Mhz high quality oscillator... Anyway one may find a good 27 Mhz oscillator for 105... Once this is done, both players model will benefit...
P.S. In my earlier post I meant about Mediatek chip, and not Cmedia chip. Sorry for the fault.
P.S. In my earlier post I meant about Mediatek chip, and not Cmedia chip. Sorry for the fault.
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Hey Ric, can we be friends and change the tone. I'd rather have it that way. Seems I say anything and you just want to clamp down on me?
Great, 25MHz and we are in agreement. Glad about that.
But on to something far more important, these SAW Oscillators are by far the best I have heard, period.
With the '105 we seem to have heated agreement on 27MHz, that is where the focus will be. And here is my concern, I can get 50MHz SAW, but nothing lower freq available. Using 4040 chip @ 2:1 I realised I should get 25MHz, so I tried it and I am getting an unbelievable result. The improvement is so obvious in every way.
There is something about these SAW oscillators, and yet they are ignored by the audio and DIY fraternity so far. I think they are fundamentally superior on some way, they are supposed to have much greater stability than the usual oscillators (which is rarely mentioned as BAW). That word "stability" caught my eye and give it a whirl. Was I surprised or what?
Now it seems that '105 will be a backwards step, as how do I get 27MHz from a SAW? Yes, 25MHz for 50MHz, but 27MHz looks a bridge too far?
Coris is using the SAW on the Sabre DAC, so he knows how good it is. I know there are other clocks out there like the Crystek 100MHz used by the Buffalo guys. Perhaps by you have tried it too?
I would rather work together on this: My gut feeling is that the SAWs are even better. I would love you to try one on the 100MHz in your 95 or 105, they are dirt cheap, so why not:
XG-1000CA 100.00MHZ
If you end up agreeing with me on the SAW solution, then I used 50MHz/2 = 25MHz for '95 with similar amazement, again dirt cheap:
XG-1000CA-50MHZ
But with '105 we need to find a 27MHz solution. I don't know how, but if we agree that SAW is the way to go, and let others know, then we are doing a service for all, and maybe even get them to make them in frequencies for audio use. I was hoping to find some 54MHz and divide it, but 27MHz is no chance unless we point out to the powers that be that they are ignoring a sizeable market.
But maybe just get a cheap 100MHz SAW and try it - but don't judge them on price as that really has nothing to do with it.
Can we work together on this?
I don't want the '105 to be a backwards step.
Cheers, Joe R.
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Yes, that is a definite possibility. But I have not able to find any SAWs @108MHz.
The 74HC4040 is rated 90MHz "maximum operating frequency". I imagine that is input freq. Do they make them higher than that?
I do know this much, we need to come up with a working solution, or else the '105 will be inferior to the '95 - based on what I have here.
Cheers, Joe R.
I meant an good quality standard 108 Mhz oscillator (not SAW). It may be dividers which goes upper than 90Mhz... I just suppose now on this. I did not researched yet about...
I think I will try first an upper frequency oscillator than 27Mhz to see what may happen... What about if it function well with 30Mhz and you may find an SAW 60Mhz...? For example.
I think I will try first an upper frequency oscillator than 27Mhz to see what may happen... What about if it function well with 30Mhz and you may find an SAW 60Mhz...? For example.