[germanium]

Quote:

Originally Posted by rds /img/forum/go_quote.gif The circuit has output caps because it is implemented in a way that requires them. Just because you don't measure DC doesn't mean there'll never be DC. Only bypass them if you're ok with potentially frying your headphones and/or speakers.

That is a possability if you are driving a direct coupled amp of any sort in which case you may not only fry the speakers or headphones but the amp also. Most amps nowdays are direct coupled & some are D.C. coupled. The chances of that happening though are extremely low as long as you measure the D.C. offset before hooking to anything after modding. The opamps are not really failure prone. They are being operated at well below thier capabilities as are the voltage regulators on the soundcard. Many soundcards come fully D.C. coupled from the factory including the Xonar D2/PM-D2X. These cards in fact use the same exact opamp combo as the STX-ST which are capacitor coupled. The only difference is the package of the opamp not the opamp itself.

 

[patrocle]

Hi everyone,
Does someone knows the meaning of those not used but connected pinout ? (in the green rectangle)
Or where Can I find the shematic for it?



I'd like to get the 4 Spdif stereo OUT (FRONT, SIDE, BACK, SW/C) like I was able to do it on Creative Sound Blaster following this shematic (Spdif0 OUT, Spdif1 OUT, Spdif2 OUT, Spdif3 OUT) :

Thanks for any help !

 

[pong38]

Hi all,

I just bought the Xonar D1 and I am very pleased with it.
But after reading this great posting about upgrading the Xonar card I'd like to give it a try.
My goal is to get the best possible stereo only sound from my setup.
The Xonar card is connected from the front output to my Yamaha receiver.

Soldering is not a problem but getting the goodies here in Holland for a stereo upgrade could be an adventure.
And while there has been quit a few upgrades after the start of this topic, I hope that someone is willing to make a shopping list with part-no's and manfact. names. It def would help me a lot.

Thanks in advance

 

[ROBSCIX]

I would suggest changing out the front channel opamp first as this will improve your stereo output. This is a good place to start then if you want get into the more involved modifications.

 

[pong38]

Quote:

Originally Posted by ROBSCIX /img/forum/go_quote.gif I would suggest changing out the front channel opamp first as this will improve your stereo output. This is a good place to start then if you want get into the more involved modifications.

I totally agree with you and I want to take one step at a time so that I can understand or better, hear what a change will do with the sound.

I never liked flying a DC9 so I go straight for the Space Shuttle... meaning... what's the best opamp to choose ?

 

[Yangorang]

Quote:

Originally Posted by pong38 /img/forum/go_quote.gif I totally agree with you and I want to take one step at a time so that I can understand or better, hear what a change will do with the sound. I never liked flying a DC9 so I go straight for the Space Shuttle... meaning... what's the best opamp to choose ?

The whole "best opamp" thing is very much based on personal opinion, but personally I like the LME49722 and AD8620 quite a bit. I hear the Burr-Browns are good too but I haven't tried any of them yet.

 

[pong38]

I'd like to start with the AD8620 and I found them quit cheap on ebay. But they will be shipped from Honk Kong or mainland China.
Or those any good or el-cheapo rebuilds ?

2pcs, AD8620 SMT Dual Op Amp IC'S IC CHIP NEW - eBay Delay, Echo Reverb, Effects Pedals, Parts Accessories, Guitar, Musical Instruments. (Eindtijd 25-apr-10 12:41:16 CEST)

And, sorry for the n00b question, what is the difference with the A and AR version of the 8620 ? Which one to take ?

 

[Yangorang]

Quote:

Originally Posted by pong38 /img/forum/go_quote.gif I'd like to start with the AD8620 and I found them quit cheap on ebay. But they will be shipped from Honk Kong or mainland China. Or those any good or el-cheapo rebuilds ? 2pcs, AD8620 SMT Dual Op Amp IC'S IC CHIP NEW - eBay Delay, Echo Reverb, Effects Pedals, Parts Accessories, Guitar, Musical Instruments. (Eindtijd 25-apr-10 12:41:16 CEST) And, sorry for the n00b question, what is the difference with the A and AR version of the 8620 ? Which one to take ?

I actually don't know of an A version, only of the 8620AR and 8620ARZ versions. I think the only differences between those two are RoHs certification. Then there's the BR and BRZ which have a few little differences in the datasheet specs from the AR/ARZ.

I don't really know of any common knockoffs of AD8620s or anything....but you never know the Chinese have amazed me at times...
Samples can be requested for the AD8620ARZ and the LME49722MA so you could try that as well.

 

[altcomp]

I am a USA distributor and I have in my stock AD8620ARZ about 300 Pcs.
Feel free to contact me for a quote.
 
tim @ checkstox.com

 

[Tacoboy]

I just ordered a Xonar DX, where can I find the latest info on doing mods on the Xonar DX.

 

[Tacoboy]

 
Quote:

Hi everyone,
Does someone knows the meaning of those not used but connected pinout ? (in the green rectangle)
Or where Can I find the shematic for it?



I'd like to get the 4 Spdif stereo OUT (FRONT, SIDE, BACK, SW/C) like I was able to do it on Creative Sound Blaster following this shematic (Spdif0 OUT, Spdif1 OUT, Spdif2 OUT, Spdif3 OUT) :

Thanks for any help !

I would "guess" that is were they hook up the card to test it, after it is built and before it goes into the box.
 

 

[TsukikoChan]

Hi guys,
 
I'm thinking of modding my DX card recently and started reading over this thread again and I've got a few wee questions if anyone can help.
 
I got a list of various caps and op-amps that can be gotten for this but some of the suggestions I cannot find. For instance, the initial post mentioned using nichicon muse kw caps for step 2 and hz caps for step 3. I can't find these, I can easily find KZ, FW, ES, DB/GB, FG and KG in the UK and I was wondering if the HZ and KW are just rebranded now? I'm not really big into my audio mods (this will be my first one), and I don't mod very often, so I'm somewhat confused between the different types of caps that can be used.
 
There were a few OP-AMPs mentioned and I was wondering what should one look for in OP-AMPs? I found a nice guide for the different sound off different OP-AMPs, and I was curious what one should aim for when replacing the front channel OP-AMP. Does one look for better treble, better clarity, better bass? Considering I will be using a speaker/decoder system with my card, I don't think I will need additional bass off my front channel speakers if I will have a subwoofer channel.
 
On that note, do most of the modders here replace more than just the frontchannel OP-AMPs? I mean, is there benefit in replacing the side channels, back channels, sub, center or front port chips? What would be the best suggestions if I were to start replacing extra chips.
 
Last question (I promise!), is there a more clearer photo for the power supply mod? Or would I be correct in assuming that the negative pins of both caps are connected to both center wires and the positive pins to the outside wires of the power supply?
 
Thanks tonnes guys! Really looking forward to what I can improve in my sound system here!
Holly

 

[rds]

 

Before we get started I want to say that: 
1.  From a technical standpoint an improvement in the circuitry based on post #1 is questionable to say the least
2.  Cap choice is an area of audio black magic (like so many areas of audio).  It generally defies any kind of quantitative description and so improvements exist in the mind/ears of the user rather than in technical benchmarks
3.  Swapping op-amps is a questionable practice - particularly when all the details of a circuit are not known (ie here)
4.  Regardless modding can be fun
Quote:

Hi guys,
 
I'm thinking of modding my DX card recently and started reading over this thread again and I've got a few wee questions if anyone can help.
 
I got a list of various caps and op-amps that can be gotten for this but some of the suggestions I cannot find. For instance, the initial post mentioned using nichicon muse kw caps for step 2 and hz caps for step 3. I can't find these, I can easily find KZ, FW, ES, DB/GB, FG and KG in the UK and I was wondering if the HZ and KW are just rebranded now? I'm not really big into my audio mods (this will be my first one), and I don't mod very often, so I'm somewhat confused between the different types of caps that can be used.

 
No those are different caps.  I chose hz for their low esr and kw because they are compact audio grade caps.  Yes, cap choice can be very confusing - I suggest looking for low esr for step 3 and audio grade compact for step 2.
 
Quote:

There were a few OP-AMPs mentioned and I was wondering what should one look for in OP-AMPs? I found a nice guide for the different sound off different OP-AMPs, and I was curious what one should aim for when replacing the front channel OP-AMP. Does one look for better treble, better clarity, better bass? Considering I will be using a speaker/decoder system with my card, I don't think I will need additional bass off my front channel speakers if I will have a subwoofer channel.
 

I'd suggest using an op-amp with similar characteristics to the one you're replacing (which is this one: http://www.onsemi.com/PowerSolutions/product.do?id=NE5532AD8R2G).  Here is a similar op-amp with better specs: http://www.national.com/pf/LM/LM4562.html#Overview  I suggest using this one.  It also happens to be the op-amp used in the xonar stx.
As far as bass, treble, clarity, etc I'll leave that to threads that discuss (often in painstaking detail) the purely subjective merits of various op-amps.  Take these threads with a healthy dose of salt.
 
 
 

 
Quote:

On that note, do most of the modders here replace more than just the frontchannel OP-AMPs? I mean, is there benefit in replacing the side channels, back channels, sub, center or front port chips? What would be the best suggestions if I were to start replacing extra chips.
 
 

Why replace other channels?  Well because you're going to use them I guess ...in my case I only listen in stereo.
The suggestions for replacements would be the same as the front channel.
 
 
Quote:

Last question (I promise!), is there a more clearer photo for the power supply mod? Or would I be correct in assuming that the negative pins of both caps are connected to both center wires and the positive pins to the outside wires of the power supply?
 
Thanks tonnes guys! Really looking forward to what I can improve in my sound system here!
Holly

Sorry there isn't.  The two center pins are not connected together (I think that's what you're asking).  However, as I remember they are connected in the board circuitry so it wouldn't really matter.  Anyways, to be safe do not connect them together.
You're welcome and have fun!  ...and try not to kill your card, cause that's not much of a mod

 

[TsukikoChan]

Thanks rds for the comments ^^ it really helped me. modding is definately fun, i've done it for arcade sticks and games controllers but nothing as expensive or sophisticated as a sound card.
 
Will do, i'll look into caps that fall under that category for audio. is it ok if i check with you guys from a few of my finds before i order any? I can find the ones you mentioned for option1 but im confused by your statement about bypassing them. did you mean you used more than just 2 ES caps for that option?^^
 
oouu, it's also somewhat cheap :O
 
that's true. i think since i intend to be using surround sound more often with my pc, i shall replace all the op-amps for the 8 channels. which brings me to the question, will the lm4562 work for all 8 channels as it looks as though the original op-amps for the surround channels have different ids than the front channel one (or i'm misreading them from the photo).
 
Ah, on further inspection they aren't connected in the photo as you say. It's just that the solder joint on the closest center pin (from the camera) is positioned so perfectly in the photo it made me think it was soldered onto the third pin too. my bad!
 
yup, i definately don't want to kill this card :3 it's served me well these last few months.

 

[Danthrax]

I think I'm going with this op-amp:
 
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=LM4562MA-ND
 
But I have no idea what caps to get (really clueless) So if anyone can point me to some caps on digikey or some other site that also has the opamps (want to save on shipping) that would be great.
 
edit: Ebay would be ok too it seems there is more of a selection there still not 100% sure what I;m looking for in a cap though...