As I have mentioned earlier, the last version of STX it have an improved sound out of it as it is. This it may be doe to the new chip (ASmedia) on the board, clocked by the 33Mhz oscillator.
I have not changed yet the 24,576Mhz resonator for Asus 100 chip to observe an even improved quality of the sound. But it may be promising doing so...
I have not changed yet the 24,576Mhz resonator for Asus 100 chip to observe an even improved quality of the sound. But it may be promising doing so...
Ahhh...sorry Coris, I missed that.
Weird about the version numbers though, being backwards...?
However , the model numbers are different on each card as well. One is a AV100_I the other, AV100A. Perhaps that's the hardware version of that specific model...?
I have a pair of the original Xonar D2's, which go back a few years more even, and they use the AV200 processor...which I was under the impression, was a rebranded C-Media chip...?
Of course it's a 7.1 card, which I think is what's different between it and the AV100
The one shown is a rev. 1.04
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I dunno how modifiable these are...
No sockets on the OPAmps, surface mounted, lower quality caps...however, it is loaded with (what I can see) 4 BurrBrown chips...
The oscillator looks readily accessible...
The PRS jacks could be replaced with quality RCA's (at least just the 2-channel out).
Or would I be better off starting with STX?
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No sockets on the OPAmps, surface mounted, lower quality caps...however, it is loaded with (what I can see) 4 BurrBrown chips...
The oscillator looks readily accessible...
The PRS jacks could be replaced with quality RCA's (at least just the 2-channel out).
Or would I be better off starting with STX?
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What settings do you see an improvement in?
Have you tried Fidelizer?
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There is a difference between ST/STX boards, when about their versions numbering and another Asus Sound Cards. They have maybe a logic with this kind of numbering.
As a common sense logic says, it may be also AV200 processor a better/advanced edition of AV100. ST/STX it use a older CMedia chip called by Asus AV100, and a newer one (better) AV200 on another kind of boards... I really don`t know how Asus thought about it, or what it may be the difference between these chips.
Another thing is that a series of boards use PCM1796 DAc chip which is inferior to PCM1792 as parameters.
ST/STX witch it may be a kind of high end audio board it use an older AV chip and a better DAC chip. This was about v1.02. Version v1.00 it seems to use a better/newer processor chip (ASmedia), and AV100A (maybe a better edition of AV100). This board version it seems to sound better anyway than the older one.
There is a kind of mess in all this so for an outsider, but maybe Asus it have a logic about.
As a rule, the improvements for all these boards is to have a better PSU on it (analogue PSU for analogue stages) better filtering (caps), a better clock system (oscillator), and a better I/V and final stage opamps.
The details of all the necessary modifications is to be decided by the modder himself. There are many opamps chips or oscillator to be used. The price it may also be a important factor.
When about Fidelizer. One may know that this software it change the registry of Windows in a way where it is not possible to be reverted, even after uninstall. More, about many of this changes the user have no any control or knowledge. One may change something in OS, but it may not know very well what it were changed... So use it on own risk!
There are another tweaks out there (google it) which refer to the OS registries and these works. There are not many. There is a quite a job to collect these tweaks, so one may do this using own time...
There is a small software too, TimerResolution which modify the windows timer resolution, lowering it to max. From standard 15ms to 0,5ms. This is recommended to be used. It improve the streaming process in whole system. Whole video/audio data transfers in a modern computer system are based on streaming processes. The hard disks data transfer too. There is beneficial to have a (software) clocking system which it works on the higher frequency than the Microsoft have planed for many years ago, when the technology were quite primitive.
I also recommend for interested one to read this thread from the beginning. There are useful informations, but unfortunately there are no more pictures...
As a common sense logic says, it may be also AV200 processor a better/advanced edition of AV100. ST/STX it use a older CMedia chip called by Asus AV100, and a newer one (better) AV200 on another kind of boards... I really don`t know how Asus thought about it, or what it may be the difference between these chips.
Another thing is that a series of boards use PCM1796 DAc chip which is inferior to PCM1792 as parameters.
ST/STX witch it may be a kind of high end audio board it use an older AV chip and a better DAC chip. This was about v1.02. Version v1.00 it seems to use a better/newer processor chip (ASmedia), and AV100A (maybe a better edition of AV100). This board version it seems to sound better anyway than the older one.
There is a kind of mess in all this so for an outsider, but maybe Asus it have a logic about.
As a rule, the improvements for all these boards is to have a better PSU on it (analogue PSU for analogue stages) better filtering (caps), a better clock system (oscillator), and a better I/V and final stage opamps.
The details of all the necessary modifications is to be decided by the modder himself. There are many opamps chips or oscillator to be used. The price it may also be a important factor.
When about Fidelizer. One may know that this software it change the registry of Windows in a way where it is not possible to be reverted, even after uninstall. More, about many of this changes the user have no any control or knowledge. One may change something in OS, but it may not know very well what it were changed... So use it on own risk!
There are another tweaks out there (google it) which refer to the OS registries and these works. There are not many. There is a quite a job to collect these tweaks, so one may do this using own time...
There is a small software too, TimerResolution which modify the windows timer resolution, lowering it to max. From standard 15ms to 0,5ms. This is recommended to be used. It improve the streaming process in whole system. Whole video/audio data transfers in a modern computer system are based on streaming processes. The hard disks data transfer too. There is beneficial to have a (software) clocking system which it works on the higher frequency than the Microsoft have planed for many years ago, when the technology were quite primitive.
I also recommend for interested one to read this thread from the beginning. There are useful informations, but unfortunately there are no more pictures...
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I've read thru this post and the two other posts at head-fi...
However, I'm modding a D2, which is significantly different to the ST, as you can probably see from my pics.
All the power for the D2 comes from the PCI slot...no external PSU connection.
I guess my only option for the card would be better reg's, and better filtering.
Here is the power section. Looks like the reg's and caps all lined up nicely
Looks like a simple layout of all components.
The oscillator is pretty evident in the topography as well...however, I dunno if this piece is good or garbage. Replacing it and giving it a nice smooth 5V would probably be a recommended.
It looks as if it's simply soldered at each end (easy to remove).
All my caps as well, seem to be sitting in a plastic "seat" and this seat also has the solder pads easily accessible from either side (my PCB is almost entirely surface mount. No thru-pins except on the "white Lego blocks...caps?)
As for OPAmps, I would have to attempt to remove the old ones and solder in sockets for the replacements. Yikes!
The I/V section...I don't even know what that is! Or where on my card to find them.
Fidelizer I don't think makes any reg changes...just reconfigs services. However the settings are installed until you reboot. No installer...no task bar app running, ect.
I don't know how to use Timeresolution...?
Seem you have to complie a script or something?
Also in my mainboard bios, there is HPET.
Might help improve clockings/timings.
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I have not analysed in detail D2. The problem with the power supply in these sound boards is that specially for ST/STX the analogue rails for opamps in analogue stages is wrong designed and implemented. They used 7812 regulator to obtain 12 v from computer PSU of 12v... Anyway the used opamps need +/- 15v to work in specified parameters... The negative rails is obtained from a small switching PSU on board.... and is not at all equal to the positive rail.
I do not know hot the power system is designed on another boards, but if is enough right done, then is not so much to mod in this area. The filtering is to be only improved. At last I prefer to have serial regulators for the opamps on analogue stages, feed it from an separate transformer (computer independent). Computer power rails are enough noisy.
Timer resolution is quite easy to be used. It is described on that site how to set it up. You have to set these parameters on the short cut of the exe file: -hide -max. Then put the short cat in to Start up folder and that`s it. It starts at the system start, and lower the timer resolution to 0,5ms (or more, it depend on the system hardware). This clock resolution is not in connection with the system hardware clock system. It is controlled by the OS it self accordingly its tasks and so on. There is the OS which it take control over the computer clock system, when it start up. Well, at last is quite complicated all this...
Good luck with mods on D2! Maybe you will come back in the thread with your results...
I do not know hot the power system is designed on another boards, but if is enough right done, then is not so much to mod in this area. The filtering is to be only improved. At last I prefer to have serial regulators for the opamps on analogue stages, feed it from an separate transformer (computer independent). Computer power rails are enough noisy.
Timer resolution is quite easy to be used. It is described on that site how to set it up. You have to set these parameters on the short cut of the exe file: -hide -max. Then put the short cat in to Start up folder and that`s it. It starts at the system start, and lower the timer resolution to 0,5ms (or more, it depend on the system hardware). This clock resolution is not in connection with the system hardware clock system. It is controlled by the OS it self accordingly its tasks and so on. There is the OS which it take control over the computer clock system, when it start up. Well, at last is quite complicated all this...
Good luck with mods on D2! Maybe you will come back in the thread with your results...
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My electronic experience is pretty limited...but even I know that a 78XX reg needs a surplus of 1-2V for it to operate properly! I dunno if I can increase opamp V on this card as all it's power is derived from the PCI slot. I can't fully read the numbers on my reg's either because of the moulded dot on the surface, other than the first 2 digits. One is 78XX and one is 79XX (the 79XX maybe the negative 12V reg?).
If one reg is for analog and other for digital (don't see why this would be though, as there is no powered headphone amp on this card) then I could simple disconnect the reg and feed it proper V externally.
All my Burr Brown DAC's are 1796...which I think are a step up from the 1792's on the ST?
Thanks for your feedback Coris!
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If one reg is for analog and other for digital (don't see why this would be though, as there is no powered headphone amp on this card) then I could simple disconnect the reg and feed it proper V externally.
All my Burr Brown DAC's are 1796...which I think are a step up from the 1792's on the ST?
Thanks for your feedback Coris!
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I wonder...swapping out the power regs and replacing them with this...
http://www.partsconnexion.com/regulator_belleson_sp78.html
Kinda pricey, if you're thinking 12V+, 12V-, and 5V
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http://www.partsconnexion.com/regulator_belleson_sp78.html
Kinda pricey, if you're thinking 12V+, 12V-, and 5V
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I think is not bad, but the price is quite high, and it may be enough big... Anyway here is to be used very/ultra low noise regulators.There are out there ultra low small chip regulators.
One may isolate only the few targeted analogue chips on the board, and use high quality regulators only for these stages. So, it will not be necessary of big and powerful regulators for quite high currents...
One may isolate only the few targeted analogue chips on the board, and use high quality regulators only for these stages. So, it will not be necessary of big and powerful regulators for quite high currents...
There are 2A and 500mA versions available.
Seeing as a 78XX and 79XX need more than 12V to work properly, maybe an external 12V source would be preferable...and quality regulators used on the 5 and 3.3V lines...
This regulator needs a minimum if 12.5V input to work properly, which a Normal PSU MIGHT output....
Burson also has a digital clock module with its own "quiet" power source...also pricey though.
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Seeing as a 78XX and 79XX need more than 12V to work properly, maybe an external 12V source would be preferable...and quality regulators used on the 5 and 3.3V lines...
This regulator needs a minimum if 12.5V input to work properly, which a Normal PSU MIGHT output....
Burson also has a digital clock module with its own "quiet" power source...also pricey though.
Sent from my iPhone...
Looking more closely at my power reg's, what I thought were 7812/7912's are actually 7808/7908's. 8V power...wtf would these be used for? Analogue?
I can't imagine 12V coming into the card from the PCI slot without smoothing/regulation.
If it's coming in from the slot, I don't see any easy way to bypass it for external -+12v
Ugh!
Here is the PCI slot pinout...
The -12 and +12V are right near the back of the card, however, looking at my D2, it doesn't look like there are any traces coming off these pins!
Anyone care to comment? Are my OPAmps powered with just 8V....??
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I can't imagine 12V coming into the card from the PCI slot without smoothing/regulation.
If it's coming in from the slot, I don't see any easy way to bypass it for external -+12v
Ugh!
Here is the PCI slot pinout...
The -12 and +12V are right near the back of the card, however, looking at my D2, it doesn't look like there are any traces coming off these pins!
Anyone care to comment? Are my OPAmps powered with just 8V....??
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With 8V regulators, it must be drawing 8+ 2-4 V from somewhere.
I guess from here I'll have to take some direct measurements from the 7808 pins 1 & 2 and see what I have.
Edit: Okay...11.8V feeding the 7808 and 7908 and 5V regulators.
The operating supply V for the JRC 2114's is 3V to 20+V, so it's totally reasonable that they are being supplied -+8V. However, the 7908, I'm only measuring about 6V, not 8. I wonder why this is.
In comparison to the Essence, which I believe the OPAmps are fed 12V from 7812, the D2 design looks like it provides more stable -+ V even though it's just 8V...?
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I guess from here I'll have to take some direct measurements from the 7808 pins 1 & 2 and see what I have.
Edit: Okay...11.8V feeding the 7808 and 7908 and 5V regulators.
The operating supply V for the JRC 2114's is 3V to 20+V, so it's totally reasonable that they are being supplied -+8V. However, the 7908, I'm only measuring about 6V, not 8. I wonder why this is.
In comparison to the Essence, which I believe the OPAmps are fed 12V from 7812, the D2 design looks like it provides more stable -+ V even though it's just 8V...?
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I have not deal it much with D2, so I can not know enough about this board. I can recommend to try to track the power lines, by measuring the regulators input, as the tension on the big filtering caps on the board. So one may find the source of the power lines. It seems to me that 8v is actually used for opamps. One can confirm this supposition by measuring the power pins of these opamps. Am extender for PCI slot it will be very handy in this case...
One may not forget that the board is a multilayer PCB. So some power lines it may be inside the PCB, connected by vias on the surfaces...
One may not forget that the board is a multilayer PCB. So some power lines it may be inside the PCB, connected by vias on the surfaces...
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