[bavarianblessed]

Maybe I'll have better luck here, 
 
Anyway, I have a Forte that "died" on me a year and a half after buying it. It started emitting a hella loud clipping noise when powered on for more than 5 minutes so I pulled it out and replaced it with a cheap Asus Xonar DGX. Anyway, fast forward to yesterday and I thought I might see if I could get it running again. All the standard radial caps (not can) on the board are crappy sam young caps. I had some Nichicon KT audio grade caps that matched the power supply cap values so I swapped them out and voila! The card works again


Now my question is this: Would the caps that I replaced, circled in red here, be better off if I used something with a lot more ripple and lower ESR or are the KTs good enough to do the job? I know different amplifier types require different spec caps. The stock values are 16v 470uf so I was looking to swap THESE for the KT series.

 

[bavarianblessed]

Nobody wants to take a stab at this even? What section should I be posting questions like this in?

 

[Logistics]

It is not good practice to move from regular electrolytics to polymers when dealing with the power-supply stage because you change the way that stage behaves, and it can have adverse effects.  The best solution is to replace garbage-brand caps with quality-brand caps such as Panasonic/Nichicon/UCC, etc.  But if the capacitor was a general-purpose capacitor (and in a PSU stage, they often are) you should replace it with a general-purpose cap.  Although, if the PSU stage had 85-degree caps, moving to 105-degree is widely accepted.
 
Out of curiousity, how are you using this card?  Headphones?  Speakers?  External DAC + headphones?

 

[bavarianblessed]

Thanks for the reply! I'll be using it coupled with an objective2 on my DT-990 250 ohms. So no harm in using the Nichicon "audio" caps I have now and I assumed as much. Would I benefit from going with a higher capacitance, 105c rated electrolytic? I try to stick with Nichicon or Panasonic any time I have to replace caps.

 

[Logistics]

Changing the value will affect the behavior of the circuit as well. What was your goal in increasing their value? Were you hoping for more bass?

 

[bavarianblessed]

I'd love to warm up the sound and provide a little more bottom end. Really at this point though I'm tinkering to figure things out. Obviously I don't know much about amplifier circuits but I was hoping the additional ripple would help provide more power for a more dynamic sound. Am I even close in that assumption? Would you be able to recommend a starting point where I can read up on the basics?

 

[Logistics]

This sort of thing could go on for seemingly, eternity so I'll just leave a random article which I've enjoyed in the past:
 
http://www.reliablecapacitors.com/pickcap.htm
 
What interests me about your card are the large capacitors on the output of the line-level output, the front channel.  I'm assuming these are decoupling capacitors of some sort, but I don't understand why they need to be so large.  My first inclination would be to replace these with smaller films.  Or at the very least to bypass them with small films.  I need to research this stage more heavily to understand why they chose these large electrolytics.

 

[bavarianblessed]

Thank you for the link sir. Those are Nichicon Muse ES caps, bipolar at 33uf 25v. I do know that none of my other sound cards are equipped with a similar layout. Auzentech prided themselves on providing higher quality sound than the equivalent Creative cards so I'm sure they served a legit purpose.

 

[Logistics]

Oh, if that's the case then it's great that they used bipolar caps, though I don't know how they landed on a value of 33uF. I am assuming it is a compromise of price, quality and real-estate. Typically, at line-level a film between 0.1-1.0uF is used in a location like this. However, they could have had other goals in mind, including boosting the low-frequency output. The larger value would serve this function, but would also reduce the high-frequency output.

In any case, if this were my card, I would replace the electrolytics with 1.0uF films. The reason I feel this is more crucial than normal is because you have double the concern as far as signal quality, between your analog output stage and the analog input/output of your external amp. Preserving the line-level signal quality up to that point would be high on my priority list.

 

[bavarianblessed]

Oh, if that's the case then it's great that they used bipolar caps, though I don't know how they landed on a value of 33uF. I am assuming it is a compromise of price, quality and real-estate. Typically, at line-level a film between 0.1-1.0uF is used in a location like this. However, they could have had other goals in mind, including boosting the low-frequency output. The larger value would serve this function, but would also reduce the high-frequency output.

In any case, if this were my card, I would replace the electrolytics with 1.0uF films. The reason I feel this is more crucial than normal is because you have double the concern as far as signal quality, between your analog output stage and the analog input/output of your external amp. Preserving the line-level signal quality up to that point would be high on my priority list.

I'll do exactly that then I enjoy tinkering and learning through experimentation so I really appreciate your input here. I'll post updates and pics as I modify

 

[Logistics]

That's exactly what I did, experiment.  I originally did this on my old, Soundblaster Live!--I replaced the electrolytics (both were 10uF each) with 0.1uF films, and the bass did suffer a bit due to the low value (they were just ancient polystyrene films that I pulled out of an old monitor), but they were so clear, the imaging so amazing, and that was then I first got a taste of how films sound.  And I heard all sorts of sounds, instruments and voices that I didn't even know were in the recordings I listened to on a regular basis.  I had to listen to my entire music library ALL OVER, AGAIN just to hear what I had been missing.
 
But anyway, I was just going to say that the rule-of-thumb when upgrading to films is to use polypropylene, and if they are too large or expensive, use metallized polypropylene, but you can use a number of films and you'll still get the amazing sound, polyester, metallized polyester, mylar, etc.  Digi-Key sells all varieties of these, but they aren't stocking anything appropriate, right now so I would suggest something like these:  https://www.parts-express.com/dayton-audio-pmpc-10-10uf-250v-precision-audio-capacitor--027-210
 
You can find whatever you want that's similar, but make note of their 1% tolerance, which means the chances of each capacitor sounding different from the other is miniscule.  Whereas, those electrolytics are 20%, and unless you bought a bag of them, and tested them to find all the values, it would be hit or miss to find a matched pair.
 
Can't wait to hear about your results... this is giving me the bug to upgrade some old PCI cards.