[Apocalypsee]

Quote:

Originally Posted by trodas /img/forum/go_quote.gif Hmmm! All in all, this is not a bad idea either. The card is "muted" till the drivers did not kick in and unmute it, that is the audio "click" or more likely a "wave" that bumps when windowns load the drivers... I quess you did not hear that now, because your output is all the time open, right? When bypassing them, one lose the ability to mute the card by software (or by the front pannel/remote), but come to think, I never need that Rarely I use the mute button on remote of my speakers. So maybe there is really a time to check on these components ...

I eliminate shutdown and boot up 'click' by opening my amp after Windows load

Software mute still working for me, I tested it more just now, yeah I heard things I never heard before, most notably on background (ambience)

Quote:

Originally Posted by trodas /img/forum/go_quote.gif It is likely that during the opamps soldering you produced (or it was there from the start?) a shortcircuit that when on load, produced various disconnections and reconnections that you hear as the high-frequency spikes and distortions. Simply resoldering the left channel muting transistor would be sufficient to get the bugs out

Nope its there even on stock, I have a picture here The top one is modded but BEFORE it have any distortion problems, the bottom one is what currently I do, using RCA out directly from opamp out

Quote:

Originally Posted by trodas /img/forum/go_quote.gif As for the muting transistors - do you know what are they? The gang of 6 of them on the top of the card, just above C19 and C18 seems to me more like transistors to shutting down the 10 pin Creative connector in/out signals?

Hmm, yeah looks like it, I sense you gonna remove them are you

Quote:

Originally Posted by trodas /img/forum/go_quote.gif What are these six 02Nf "things" with six legs before the opamps anyway?

You mean after the opamp on surround opamp? I don't know, maybe different type of muting capacitor

 

[Apocalypsee]

Here's my card now. I named it PureMusic™, since there is no opamp to 'color' the music. Since I have limited small value capacitor that high quality, I use Elna bipolar 10uF 25V with 0.47uF Phillips MKT as bypass. The bass rolloff is quite obvious, at 20Hz is -13dB while 40Hz is -4dB. Y eah the card is very messy, but at least it sounds nice

 

[trodas]

Quote:

Software mute still working for me

Of course. The main chip just stop supply the DAC with data, that is easy

Quote:

Nope its there even on stock, I have a picture here The top one is modded but BEFORE it have any distortion problems, the bottom one is what currently I do, using RCA out directly from opamp out

Interesting. So, how do you fixed that? Just getting rid of opamps and the muting transistors and taking the signal directly from DAC?
Maybe it is a time to recap these poor failing Jamicons...

Quote:

The gang of 6 of them on the top of the card, just above C19 and C18 seems to me more like transistors to shutting down the 10 pin Creative connector in/out signals?

Quote:

Hmm, yeah looks like it, I sense you gonna remove them are you

Not if they are not going anywhere near the signal path

And they did not seems to do so.

Or maybe I measured it just wrong?

Quote:

What are these six 02Nf "things" with six legs before the opamps anyway?

Quote:

You mean after the opamp on surround opamp? I don't know, maybe different type of muting capacitor

No, I mean the components on witch I can measure direct connection to the output jacks. Probably sort of muting transistors, but... I have no idea.


The muting of the output transistors is interesting idea. I think it is a fair trade to trade the clicks when drivers is loading AND when switching the audio modes for the higher detail level, don't you agree?

However I seen just this image:


That says it bypass them, however there is two main problems.
1) it is only for the L and R channels, while I need to take care about six channels - L, R, RL, RR, CENTER and SUB.
2) tracing the pins of the transistors back to the opamps output (pins 1 and 7) show no connection at all to those shorted pins!

Anyone know where the output from pins 1 and 7 of the opamps really go? The mod definitively connect well the output, but the input is wrong...

And what about the other channels?!

Here is a little drawing of what I checked to be true - X-Fi jacks connection

Any help/ideas? What I did overlook?


PS. your card looking that a bit hardcore modding was done to her!

But if that helps, then so far, so good.

 

[trodas]

Removing X-Fi muting transistors.

Having transistors in the audio loop is definitively a big NO-NO, just go ask any audiophile of Hi-Fists and he did not even need to be an extreme one to tell you this. So, I concentrated my efforts this way. First I produced this picture of what is short direct contact on my X-Fi Fatal1ty: http://i232.photobucket.com/albums/e...ps_outputs.jpg

And todays I go deeper. It is same for each output. After opamp, there is a 33ohm resistor to protect the opamp from shortcut on the end. It has minimal impact on the signal, so, keep it. Later there are two muting transistors, for the positive and negative flow:

And after them a two small caps to the ground to kill the possible high frequency interference. For L and R channels the card utilize 4 separate transistors. For the rest a dual transistor is used to save space - two (or coudl that be four?) ones in one.

Regardless, the removal is rather easy. First get rid of them:

Then solder a shorts there:

...and you are free to test them. As you probably noticed, I for the work desolder the C46 and C27. And also as you sure noticed, I replaced the LM4562 opamps with AD8599 ones.


The results.
After hearing the sound, I was like "Holly ****...!"
There is no words to describe how much better it sounds. The oversharped thick sound of the LM4562 is gone (LM4562 also like to pick a lot RFI) and the sound is rich and full - and yet more detailed - very likely thanks to these muting transistors removed!

Fantastic change, damn I'm glad I did it!

Side-effects.
As everything in life, there is a price for this. Not only this is NOT easy mod (do NOT try that, unless you are soldering MASTER, and I'm not kidding) but it also has consequences. Not only you want to delete all, even the 320kBi mp3 files now, but upon the driver loading in windows boot, there is notable click in the speakers. Same when changing audio mode. Not louder that the amp is set for, so a minor price for such wonderfull, rich sound.
There is a bigger price and I was quick to discover it.
I remember it well from measuring the voltages on the caps on X-Fi. When I touch the opamps, well, then the X-Fi started to oscilate like MAD and the resulting sound noise, even on small testing speakers, are unbearable.
So, to get to it - I plug my rear speakers into the SUB/CENTER jack, so upon discovering that, I was like fixing this. So I unplug the jack... and the moment it started. The X-Fi, no longer protected with these muting transistors, start oscilating like mad. From all 6 speakers it output SO horrible noise and SO strong, that it was like when F18 is about to land on your head.
I can't remember anything comparable in my life.
My stepbro run to my room asking What... so you get the picture.
The oscilating noise, when you change your speakers, does not stop till reboot.

For me it is fair price to pay. I just can't now hotplug the speakers of fiddle with them "on the fly", like I used to. This is kinda sad and limiting, but what one can do. I'm ceratainly not going to put these cursed transistors back, no way. I love the sound now way too much.

 

[trodas]

About AD8599 opamp
(testing made my friend, imperialreign, who have tad better ears that me and take music really seriously)

Fatal1ty with LM4562

Fatal1ty with AD8599

I ran the AD8599 tests 4-times each to make sure of those results - comparatively, the AD8599 allows for a better dynamic range at all testing levels, compared to the LM4562... it might only be an average difference of -2dbA, but for such a small component that's a lot...

THD and IMD+N results for the AD8599 are very-slightly better, the most improvement difference, though is at 16bit playbacks; coupled with the slightly higher dynamic range, I'd conclude as well that these OPAMPs aren't as affected by EMI as the LM4562.

Also of note - the AD8599 rated better at stereo crosstalk than the LM4562... meaning there's less channel bleeding.

TBH, the AD8599 sounds the same to me now as it did after first installation (surprisingly). I really also dig how they sound compared to the LM4562 as well; the 4562 OPAMPs produce some very sharp frequencies that I personally found to be annoying at times. The 8599 has a lot warmer sound, IMO it has a lot more depth to it.

For the cheaper price, I'd say it ousts the 4562.


X-Fi output DC offset measuring with original UK X-Fi, no heatsink and L+R channel NJM4556 opamp, rest NJM4558 opamps
---------------------------------------------------------------
L: 29.9mV DC, 9.8mV AC
R: 29.6mV DC, 9.8mV AC
RL: 0mV DC, 9.8mV AC
RR: 0mV DC, 9.8mV AC
CENTER: 0.2mV DC, 9.6mV AC
SW: 0.2mV DC, 9.7mV AC


******************************
The 9 - 10mV AC is a classic noise, around 5kHz. What is interesting is the VERY LOW DC offset on RL/RR as well as on CENTER/SUB channels of the original X-Fi (yours), while the L/R show around 30mV of DC offset, so not perfect at all, even at default. Looks like the X-Fi electronic design is perfectly finetuned for a NJM4558 (very low, next to none DC offset), while any other opamp is a "misfit" there. I think I should short the coupling caps between DAC and opamps first and then measure DC offset again with the original 4558 opamps...
******************************


X-Fi output DC offset measuring original UK X-Fi, shorted DAC - opamps caps
---------------------------------------------------------------
L: -179.4mV DC, 9.8mV AC
R: -204.5mV DC, 9.8mV AC
RL: -222.9mV DC, 9.8mV AC
RR: -232.2mV DC, 9.8mV AC
CENTER: -225.2mV DC, 9.6mV AC
SW: -238.9mV DC, 9.7mV AC


X-Fi output DC offset measuring with LM4562 opamps
---------------------------------------------------------------
L: -190mV DC, 10mV AC
R: -174mV DC, 10.2mV AC
RL: -210.2mV DC, 10.1mV AC
RR: -204.7mV DC, 10mV AC
CENTER: -209.5mV DC, 10mV AC
SW: -231.9mV DC, 10.2mV AC


X-Fi output DC offset measuring with AD8599 opamps
---------------------------------------------------------------
L: -219mV DC, 9.5mV AC
R: -205mV DC, 9.8mV AC
RL: -209mV DC, 9.7mV AC
RR: -205mV DC, 9.3mV AC
CENTER: -210mV DC, 9.6mV AC
SW: -232mV DC, 9.7mV AC


A word about the DC offset.

Quote:

maybe it's not safe to remove the coupling capacitors

Maybe it is not safe to live on Earth

Got my point?
Nothing is safe, ever. However the X-Fi did not have by default ANY cap between the opamps output and the jacks. So...

And the main point is, that the DC offset is neutralized on the amplifier input coupling caps. So nothing to worry about.

Unless you have custom amp with stripped input coupling caps, then you have absolutely nothing to worry about. It can only make your sound nicer and more detailed.

In some cases the input caps in the amplifier aren't even need to be there, depending on the amp input opamps and their gain versus voltage. If the gain is low and voltages high, the DC offset is just amplified like the rest of the signal and that it is. No clipping happen then. But it is wise to let one last coupling cap to have in the input of power amplifier... if you did not want end up with like 16V DC offset on the speakers

 

[trodas]

My modification of X-Fi Fatal1ty, UK edition w/o heatsink on main chip and with caps wires bent to sides and then soldered from the bottom of the PCB for user Tez, Head-Fi forum:

...and his card is working just great!

 

[Tez]

Thanks trodas, it looks great! Can't wait to hear it

 

[gurusan]

looks liek very nice work trodas

 

[trodas]

Thank you, guys

Additional infos

If you remove all the eight audio caps, you won't be able to do a RMAA measuring using loopback cable, since the input jack will not work anymore. So, to make it work, you gotta add a C48 and C49 caps. The original are bipolar 4.7uF 50V Jamicons. I used audio quality polypropylene film caps to replace them, 4.7uF 63V MKT ones (Digi-key order number 495-1131-ND ):

And then I can make my first RMAA test: http://ax2.old-cans.com/X-Fi%20Fatal...ps%2024_48.htm

It is much better that trying to pass the -200mV DC offset right back to the input: http://ax2.old-cans.com/X-Fi%20Fatality%20NOCAPS.htm

...

 

[S3am]

Trodas, thanks for interesting tweak-log. I have some questions for you. I'm using Audigy2 Value (almost the same as Audigy4, whis has about 4 caps more than value).

1. Why did you remove the heatsink? Only to make photos?

2. I have a pair of Rubycon MBZ 1000 uF 10V. Are they good caps to be placed on SoundCard? Also have some Hitano EXR 1000\6.3, but they are used and too old. Black Gate and HQ PolyPropilen isnt problem too, but if it possible, i want to spend low $amount, cause it is easier and more usefull to buy ESI Juli@ or Prodigy HD2

I cant find any big caps near the main DSP chip as on X-Fi, so can you help me to find DSP filter caps.

3. I also want to short-in the mute keys, but as i see it uses two 3pins transistor, so which pins should be shorted?

4. It 4 OpaAmps installed to A2V: 3*JRC 4558 and one 4556a. So, i think the last one used in front channels? What can You say abut replacing that with AD8066 ?

5. Two main problems of my Audigy:
5.1 It has annoyng scratches in FL channel, which has the same level at any Gain level.
5.2 The sound isnt comfortble at all. Even the radio sometimes sounds more blury, but more comfortable. Believe that tweaks helps withthis trouble.

Photo of Audigy4:
http://www.abclinuxu.cz/images/scree...-pro-52208.jpg

Also can make photos of different places on PCB if it neccesary.

 

[S3am]

Trodas, come back plz

 

[trodas]

1 - I did not remove the heatsink. The Tez X-Fi card just come w/o it. Probably a difference between US and UK sale versions? Dunno.

2 - I did not see any place on X-Fi for the Ruby MBC 1000uF cap... Maybe the Hitano could be used to the voltage filtering main cap, because it have a high ESR, but that it is. There are only DSP voltage filtering caps, near the voltage regulators. Not near the DSP, IIRC.

3 - I think the picture speak for itself and you have to short the colector to the emitor on the cap, not the base, lol.

4 - replace the opamps with any opamp you see fit. Anything is better that the oldies 4558...

5 - I do believe that your Audigy 4 card is just dying of bad caps pleague...

I wish I can come back sooner, but I can't. And I still have heap of other problems... and I do believe you trashed the card long time ago Right?