trodas
100+ Head-Fier
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Chu - Quote:
You speak the truth. They are, well, crooks.
Quote:
I count 24. 16 of these decoupling caps - C23, C50, C76, C77, C28, C55, C85, C83, C61, C32, C62, C26, C67, C36, C34 and C68 and 8pcs of caps where the audio signal also exist - C18, C19, C20, C21, C48, C49, C102, C104.
Fizzycapola - you should not be surprised, if you readed the TI PS54352 datasheed. The voltage regulator favor mild ESR caps, not low ESR ones, just a mediocre ones. Or it oscilate more. That was what happen when I used Oscon SEPC 820uF 2,5V.
Bad ideas. I should also read first.
That is also why when I soldered there a Samxon RS 3300uF 16V cap the card stop working
Even RS series of Samxons are not exactly low-ESR caps, more like slightly better general use, they stop the regulator from working well
(that means their specs is MUCH and WAY better that all the stuuupid caps mod people around here did, see there: Pictures/links to crazy cap mods - Chitchat - CapsMod Forum - Powered by Discuz!
So, the volage regulation for the main X-Fi chip is made by TI PS54352 chip.
http://www.ti.com/lit/gpn/tps54352
The recommended use is this:
From this is quite obvious, that Creative design is very bellow specs one and for example - the imput filtering elyte capacity should be at least 100uF and as close to the chip a 10uF (at least) ceramics low-ESR cap. The Creative imput filtering elyte are 22uF Jamicon (!) and I did not yet measure the ceramic one, but I fear it is not "at least" 10uF as it should be.
Measured 15uF. I should desolder it, I think I measure something else with it also...
Same for the output. I see bulk capacity there, a 330uF elyt, 100uF another low esr cap and 0,1uF ceramics. Creative used a 220uF Jamicon witch is not low ESR cap in any way, shape or form...
So now it is clear, why I get the best results with mediocre 470uF Panny FM 16V cap (mediocre because using 16V cap on 1.25V a "bit" soften it's specs) with bridged 4,7uF ceramics are best and why the ultra-low-ESR polymer was not a great there.
My fault. Now I also going to replace the imput filtering "bulk" capacity - by Creative 22uF 16V Jamicon - by me a 150uF 6.3V Nichicon HE :dev: Yet the usage of 470uF Panny FM bridged with 0,1uF ceramic cap is not so great also. I still having the "pause bug"...
Considering what might cause the "pause bug" I do wonder, how well Creative followed up the DAC recommended connections:
http://www.cirrus.com/en/pubs/proDat.../CS4382_F1.pdf
PS. I just replaced the there output opamps from the old useless (they was used even in Audigy (1) !!!) MC4558C ( MC4558CD datasheet pdf datenblatt - STMicroelectronics - WIDE BANDWIDTH DUAL BIPOLAR OPERATIONAL AMPLIFIERS ::: ALLDATASHEET ::: ) to the praised LM4562 ( LM4562 datasheet pdf datenblatt - National Semiconductor - Dual High Performance, High Fidelity Audio Operational Amplifier ::: ALLDATASHEET ::: ) opamps. It was kinda easy, however the changes are minimal. You cannot hear any difference in mp3 bellow 320kBi, that is for sure. When we talking about DTS 768kBi, well, ten there finally is some difference
But not so major. It is obvious that complete recap of the Jamicon crap caps has to be done as well, as the audiojacks has to be gold-plated for the subwoofer connection, the whole subwoofer has to be recapped and possibly modified also, so there is a notable difference.
Ask the Nartional Semiconductor for there sample pieces of the LM4562MA in the SOIC NARROW version for free there:
LM4562 - Dual High Performance, High Fidelity Audio Operational Amplifier
And you can replace the there 4558 "things" used for the output channels :dev: There is also another opamps for mic in, line in and some more down there... So maybe a 6 opamps is not a bad idea.
PS2. parts list for SB0460 - X-FI Fatal1ty:
RapidShare: 1-Click Webhosting
parts list for SB0550 - X-FI Elite Pro:
RapidShare: 1-Click Webhosting
...a good start
A few interesting (but not mine, Bichi's work) X-Fi mod pictures:
absolutely not reason to believe their business practices have changed |
You speak the truth. They are, well, crooks.
Quote:
but how many of those caps are actually in the analogue single path? |
I count 24. 16 of these decoupling caps - C23, C50, C76, C77, C28, C55, C85, C83, C61, C32, C62, C26, C67, C36, C34 and C68 and 8pcs of caps where the audio signal also exist - C18, C19, C20, C21, C48, C49, C102, C104.
Fizzycapola - you should not be surprised, if you readed the TI PS54352 datasheed. The voltage regulator favor mild ESR caps, not low ESR ones, just a mediocre ones. Or it oscilate more. That was what happen when I used Oscon SEPC 820uF 2,5V.
Bad ideas. I should also read first.
That is also why when I soldered there a Samxon RS 3300uF 16V cap the card stop working
So, the volage regulation for the main X-Fi chip is made by TI PS54352 chip.
http://www.ti.com/lit/gpn/tps54352
The recommended use is this:
From this is quite obvious, that Creative design is very bellow specs one and for example - the imput filtering elyte capacity should be at least 100uF and as close to the chip a 10uF (at least) ceramics low-ESR cap. The Creative imput filtering elyte are 22uF Jamicon (!) and I did not yet measure the ceramic one, but I fear it is not "at least" 10uF as it should be.
Measured 15uF. I should desolder it, I think I measure something else with it also...
Same for the output. I see bulk capacity there, a 330uF elyt, 100uF another low esr cap and 0,1uF ceramics. Creative used a 220uF Jamicon witch is not low ESR cap in any way, shape or form...
So now it is clear, why I get the best results with mediocre 470uF Panny FM 16V cap (mediocre because using 16V cap on 1.25V a "bit" soften it's specs) with bridged 4,7uF ceramics are best and why the ultra-low-ESR polymer was not a great there.
My fault. Now I also going to replace the imput filtering "bulk" capacity - by Creative 22uF 16V Jamicon - by me a 150uF 6.3V Nichicon HE :dev: Yet the usage of 470uF Panny FM bridged with 0,1uF ceramic cap is not so great also. I still having the "pause bug"...
Considering what might cause the "pause bug" I do wonder, how well Creative followed up the DAC recommended connections:
http://www.cirrus.com/en/pubs/proDat.../CS4382_F1.pdf
PS. I just replaced the there output opamps from the old useless (they was used even in Audigy (1) !!!) MC4558C ( MC4558CD datasheet pdf datenblatt - STMicroelectronics - WIDE BANDWIDTH DUAL BIPOLAR OPERATIONAL AMPLIFIERS ::: ALLDATASHEET ::: ) to the praised LM4562 ( LM4562 datasheet pdf datenblatt - National Semiconductor - Dual High Performance, High Fidelity Audio Operational Amplifier ::: ALLDATASHEET ::: ) opamps. It was kinda easy, however the changes are minimal. You cannot hear any difference in mp3 bellow 320kBi, that is for sure. When we talking about DTS 768kBi, well, ten there finally is some difference
Ask the Nartional Semiconductor for there sample pieces of the LM4562MA in the SOIC NARROW version for free there:
LM4562 - Dual High Performance, High Fidelity Audio Operational Amplifier
And you can replace the there 4558 "things" used for the output channels :dev: There is also another opamps for mic in, line in and some more down there... So maybe a 6 opamps is not a bad idea.
PS2. parts list for SB0460 - X-FI Fatal1ty:
RapidShare: 1-Click Webhosting
parts list for SB0550 - X-FI Elite Pro:
RapidShare: 1-Click Webhosting
...a good start
A few interesting (but not mine, Bichi's work) X-Fi mod pictures: