[ashmedai]

Quote:

Originally Posted by Dionysus /img/forum/go_quote.gif Seriously as an owner of this setup I know for a fact that the STX can drive the Senn HD650 it is quite annoying to read.

Okay. I'd still love to see stuff like a power-impedance graph etc that quantitatively speaks to how well they can do it. It's not really a can they / can't they problem. Unless it's so far into "can't they" that you can't get any useful sound at all, which we already knew isn't the case.

Or could you be more explicit/detailed than "yes they can"?

To try to get into some numbers; the Vpp on an M^3 (for a random easy-to-find example) is 24V, while the highest you're getting from that supplemental molex connector is 12V. Current should be less of a problem since there is usually 10-12A or more to play with (noting that you need to avoid using a large fraction of it to avoid screwing with disk drives etc). Also you lose some because the card probably needs to filter the power it's getting to some degree. If I'm remembering my electronics right, things like the K701 are more picky about current while others like the HD650 are more picky about voltage (in each case noting that not enough of the other will still suck). So we have abundant current but kinda meh voltage. Power, we could install an arbitrarily higher capacity power supply, but from a marketing standpoint you probably should assume you're working with the leftovers after everything else gets its pickings which may or may not impose further limits.

As you can see, I'm a bit skeptical - have explained my reasons for taking a skeptical view of blanket claims that "yes it works" - and am looking for some more specific information to back it up. If you're just going off what sounds good to you, great, and I'm happy for you, but I still hope someone with the specific knowledge and the electronics experience can help clarify this one way or another. I have just enough to have reason to be very skeptical, not enough to nail down the answer.

 

[gyrodec]

The TPA6120 that drives the headphone socket is on +/- 12v rails, so that's 24Vpp just like the M^3. So, from a volatge point of view, this thing is very much a real desktop level headphone amp.

As for power limits due to "working with the leftovers after everything else gets its pickings which may or may not impose further limits" - thats just rubbish. The power you can draw, cleanly and easily, from that molex connector is huge. That is the same power connector the 100 wat graphics cards get power through, so there really won't be any sane limit to power draw.

I've not heard it, so I'm not saying its better than an M^3, or even as good - BUT, it can swing as many volts and it does have access to any current it needs. Do a little research before getting technical with the FUD.

 

[ashmedai]

Quote:

Originally Posted by gyrodec /img/forum/go_quote.gif The TPA6120 that drive the headphone socket is on +/- 12v rails, so that's 24Vpp just like the M^3. So, from a volatge point of view, this thing is very much a real desktop level headphone amp.

See, that's what I thought at first. But when I went to look it, the wires are listed as +12V, GND, GND, +5V. The +/-12V appears to just be on the motherboard's connector. Yeah, I looked it up on Wikipedia, and Wikipedia can quite easily be wrong. If you know better, please correct me, and the Wikipedia page as well if you're feeling contributory.

Hmm. You know what I didn't check was the PCI-E bus supply. People were saying that the amp went entirely off the molex supplemental power, and it seemed reasonable for that to be true. Maybe it wasn't entirely?

--> Okay, a 1x PCI-E connection only supplies +3.3 and +12V from what I saw. So I have no idea where it would get access to -12V at this point.

Quote:

Originally Posted by gyrodec /img/forum/go_quote.gif As for power limits due to "working with the leftovers after everything else gets its pickings which may or may not impose further limits" - thats just rubbish. The power you can draw, cleanly and easily, from that molex connector is huge. That is the same power connector the 100 wat graphics cards get power through, so there really won't be any sane limit to power draw.

Possibly, but not clearly so (to me) based on your objection. Say you have a 450W supply, it can consistently supply 60% of that, the CPU wants 100W, the GPU wants 100W, you have a few hard drives that maybe want an amp between them...it adds up (to make up some numbers). You do *not* have the full supply capacity to play with (which is certainly substantial to begin with), in fact you have some rather small fraction. If you try to draw more than that, I assume it will either fail or screw with the other parts in the system.

I'd bet the remainder is still pretty substantial in many cases, but many systems with high-powered graphics cards end up with under-spec power supplies or ones that barely meet the recommended spec. So I don't think the result that an addon card has to play with safely is that large compared to the initial capacity. But - what does it need, and what is left? For reference, a number of speakers work quite merrily off of 10W or less, so I would expect even high demand phones to be in that neighborhood or lower. Obviously it's enough to do a passable job of driving phones like the HD650, because it makes sound when you plug it in. The big question is - what is the numerical difference between working and working well, and how does that compare to the leftovers you can reasonably work with?

Quote:

Originally Posted by gyrodec /img/forum/go_quote.gif I've not heard it, so I'm not saying its better than an M^3, or even as good

I certainly wouldn't expect it to be; as I mentioned it just has easy to access specs and I was reasonably confident no one would dispute the M^3 being "big enough" for most things.

Quote:

Originally Posted by gyrodec /img/forum/go_quote.gif BUT, it can swing as many volts and it does have access to any current it needs. Do a little research before getting technical with the FUD.

Yeah, there's still that Vpp thing (I think). I like technical answers because they're reliable. And I give technical reasons for my skepticism because it helps me define my objections and makes it easy for people to confirm or refute them in a concrete way that lets me know whether my objections were valid or invalid.

Thanks, I'd really like to get a clear idea on how this works one way or another.

 

[gyrodec]

This card gets no power from the bus, only from the molex. It used internal circuitry to create +/- 12v lines from the +12v comming from the molex. There are standard parts and circuits for this. I don't know how they work, but its common stuff.

To get an idea, the HD580/600/650 all max out at about 300mW, i.e. a third of a watt. Even the most many of low impedance phones take no more than 1 to 1.5W. I measured the voltage on my HD600 while listening quite loudly and it was 150mV, so thats 0.075mW. Even if you are pushing you power supply hard, the hesadphone amp will not be any meaningful load.

There are aspects to immediate current drive capacity which have nothing to do with the PC PSU, but the local storage capacitors on the baord, and more importantly, by the TPA chip itself. These are more critical to driving headphones than the PC PSU. I have no idea if the STX is well designed in that area, but it most likely is.

 

[ashmedai]

Hmm. So maybe the primary problem is the response to load rather than the static supply properties. That makes a lot of sense, actually - larger amps have much more room for large caps and transformers and so forth for fiddling with the power to get a clean supply and adequate reserve energy. Some of that you can maybe chalk up to choice of cap type, use of analog vs digital solutions...not an easy problem without a lot of electronics background, eh? But I'd think the size limitations would impose major constraints there even if the input power doesn't. Whether those are constraints you can work around or not...well, I'd like to know, but I'm not entirely sure what to ask.

I suppose I'm looking for a scientific basis for a simpler and mostly economic objection. Given that "sound cards suck for hi-fi" and that this is at the same price point as sound card mfrs have been targeting for years and years, how can it suddenly do what they couldn't? Are we just chalking this up to mfrs not bothering to market to us before? While a certain cynicism would support that, I'd like to think there's more to it. Is it "so easy" to build a part like this at that price point but no one bothered? Is there an engineering trick to it that no one tried before? Are the claims (other than the >> $700 amp telephone game thing) true about its capabilities and quality, and there are other equally good cards out there that we just haven't noticed? The "and suddenly there was an awesome card that does all the things sound cards stereotypically are inadequate at" explanation just feels really, really incomplete. Either it's wrong in some way, or we're (I'm) missing something that makes the picture fit together.

 

[scytheavatar]

Quote:

Originally Posted by ashmedai /img/forum/go_quote.gif I suppose I'm looking for a scientific basis for a simpler and mostly economic objection. Given that "sound cards suck for hi-fi" and that this is at the same price point as sound card mfrs have been targeting for years and years, how can it suddenly do what they couldn't?

Because this is one of the first audio cards aimed specifically for headphone performance? Because Asus really knows how to get good sound on their sound card? Because it's using parts like Nichicon gold capacitors that's not even found on many of the high end amplifiers?

 

[audionewbieyao]

Urr.. have you thoroughly read the data sheet of TPA6120A2 from TI?
Sorry i don't know how to past the image in PDF file, but here's the link:
http://focus.ti.com/lit/ds/symlink/tpa6120a2.pdf

TI has listed charts you want from page 5, the Typical Charactics section.

All the charts shows the audio quality of THDN's in relation to the output voltage and many other power consumption/quality related information, and they all look pretty impressive to me.

I think it could be useful to your questions.

 

[ashmedai]

Quote:

Originally Posted by scytheavatar /img/forum/go_quote.gif Because this is one of the first audio cards aimed specifically for headphone performance?

Okay, but why? I raised the "maybe no one bothered before" question myself, but I still think it's a relatively weak answer.

Quote:

Originally Posted by scytheavatar /img/forum/go_quote.gif Because Asus really knows how to get good sound on their sound card?

And no one else does or did until now?

Quote:

Originally Posted by scytheavatar /img/forum/go_quote.gif Because it's using parts like Nichicon gold capacitors that's not even found on many of the high end amplifiers?

MagicCaps syndrome FTW...

Quote:

Originally Posted by audionewbieyao /img/forum/go_quote.gif the data sheet of TPA6120A

Nice data sheet. Chip appears to be from 2004. If this is part of the answer - has any other product used this thing in the last five years, and with what results?

 

[scytheavatar]

Quote:

Originally Posted by ashmedai /img/forum/go_quote.gif Okay, but why? I raised the "maybe no one bothered before" question myself, but I still think it's a relatively weak answer.

In case you haven't realized, the sound cards from Creative, etc are targeted primarily for the gaming community and the priority is to ensure top gaming performance, not top audio quality. And yes, no one bothered to get audiophile quality on their sound card, because they don't care about audiophiles.

The argument is pointless, are you going to get your hands on a STX or not? If not please do us a favour and stay away from this thread, I think it's fair to say that the STX's headphone out wouldn't be as good as $700 amps, but to say that the STX wouldn't be better than other sound cards despite all the reasons we have given is unreasonable. Apparently you who have never heard the STX knows how it sounds better than those who have already gotten their hands on it, who are near unanimous in calling it the best sounding sound card ever...

 

[ashmedai]

Quote:

Originally Posted by scytheavatar /img/forum/go_quote.gif In case you haven't realized, the sound cards from Creative, etc are targeted primarily for the gaming community and the priority is to ensure top gaming performance, not top audio quality. And yes, no one bothered to get audiophile quality on their sound card, because they don't care about audiophiles.

Most, sure. But are you seriously trying to tell me that there is *not one* time where anyone has tried to make a card for any market that isn't? Including cards intended for pro audio work?

Hell, I know one case where there was a motherboard with a tube stage onboard. Don't tell me it's the only time anyone's tried to sell to us. Not if you aren't prepared to back it up better than that, anyway.

Quote:

Originally Posted by scytheavatar /img/forum/go_quote.gif The argument is pointless, are you going to get your hands on a STX or not? If not please do us a favour and stay away from this thread, I think it's fair to say that the STX's headphone out wouldn't be as good as $700 amps, but to say that the STX wouldn't be better than other sound cards despite all the reasons we have given is unreasonable. Apparently you who have never heard the STX knows how it sounds better than those who have already gotten their hands on it, who are near unanimous in calling it the best sounding sound card ever...

Okay, that's a pusher's argument, the old "no one can understand until they try it" used to bully reason out of the way to sell drugs and religion. It doesn't really clarify anything, and makes it sound like you don't have anything better to support it. And to boot you're putting words into my mouth, and off-track from at least what I'm wondering about.

If it's really head-and-shoulders above every other product ever, I would love to know how and why, not just be told "everyone's doing it, you can't understand until you do it too"...because that's just crap.

 

[jenneth]

Quote:

Originally Posted by scytheavatar /img/forum/go_quote.gif Because this is one of the first audio cards aimed specifically for headphone performance?

HT Omega Claro Halo was released a few months before the Essence.

Quote:

Originally Posted by scytheavatar /img/forum/go_quote.gif And yes, no one bothered to get audiophile quality on their sound card, because they don't care about audiophiles.

Onkyo SE-200 PCI LTD/SE-200 PCI, HT Omega Claro Halo, just to name a few...

.................

As for the Essence itself, couldn't we just agree that this sound card offers a level of price/performance ratio that's unmatched in the current market today? As for how good, it's unlikely that it can match a $700 HP Amp, but then again, it doesn't have to.

Personally, I'm just glad that companies like ASUS, Auzentech, and HT Omega are continue putting in efforts into making more advanced sound cards.

 

[scytheavatar]

Quote:

Originally Posted by ashmedai /img/forum/go_quote.gif Most, sure. But are you seriously trying to tell me that there is *not one* time where anyone has tried to make a card for any market that isn't? Including cards intended for pro audio work? Hell, I know one case where there was a motherboard with a tube stage onboard. Don't tell me it's the only time anyone's tried to sell to us. Not if you aren't prepared to back it up better than that, anyway.

I have already given you the reason why the STX sounds better than the other sound cards: the parts used by the STX is superior to what that's used by the other sound cards. Cutting costs by using cheaper parts is commonplace. If you think that cheaper parts doesn't have a negative effect on the sound quality, you are being unreasonable. And the STX will sound better than portable amps too, because portable amps are battery powered which is a huge limitation.

 

[audionewbieyao]

Quote:

Originally Posted by jenneth /img/forum/go_quote.gif Personally, I'm just glad that companies like ASUS, Auzentech, and HT Omega are continue putting in efforts into making more advanced sound cards.

I'm with you Jenneth.

So Ashmedai,
have you dig into TPA6210 datasheet?
Do you mind share with us since we are not that literate in elecrotniics.
Much appreciated.

 

[audionewbieyao]

Yeah, I almost overlooked those quality parts other than TPA6120, they are definitely great help in making sounds from Xonar Essence STX surperior than others.


But OTOH, if Ashmedai's sole concern is about power only, then the queston may need to be tweaked into like

Q: Suppose TI TPA6210 is capable of properly drive headphones up to 600ohm, such as HD600/HD650 etc., then was Xonar Essence STX properly designed to meet TPA6120's requirements in order to generate best performance?"

What do you think, Ashmedai?

 

[ashmedai]

Quote:

Originally Posted by audionewbieyao /img/forum/go_quote.gif Do you mind share with us since we are not that literate in elecrotniics. Much appreciated.

I'm in the middle somewhere, which you might notice as I'm learning some of this stuff in this very thread.

I've been told though that the surrounding circuit often has a larger impact on a number of things. It certainly should be more important in determining power availability and its derivatives with respect to time.

Quote:

Originally Posted by audionewbieyao /img/forum/go_quote.gif Yeah, I almost overlooked those quality parts other than TPA6120, they are definitely great help in making sounds from Xonar Essence STX surperior than others.

They're important, but there are always companies marketing their "solid Japanese caps" and so forth. It can't always be just marketing. And caps aren't magic devices either; many of the brands that get bandied about are ones builders use primarily because they're cheap and readily available parts that are still suitable to the application.

If the reason is that the part choices create a finished product that can do things no other could - were other engineers making bad choices, and how did Asus get all the competent ones? or did something drastic change in the available parts to choose from? or is Asus manufacturing this with a much lower profit margin than usual (itself begging the question of why $300 cards couldn't do it if $200 couldn't)?

Quote:

Originally Posted by audionewbieyao /img/forum/go_quote.gif But OTOH, if Ashmedai's sole concern is about power only, then the queston may need to be tweaked into like

My concern is that some very bold claims were made based on subjective and second-hand accounts. I want to know to what degree they're factual, and what it means for this and other similar devices.

And this is completely aside from the DAC section. "This sound card has an awesome DAC section" - okay, that's a reasonable claim that can equally apply to other products, so that's all fine and good. "This card has a super-awesome amp that can do things no other amp can do"...okay, starting to sound a little questionable, especially in the light of the number of wild claims and distorted second-hand accounts running around. No doubt there's a kernel of truth in there too, but the telephone game bit gets in the way of pinning it down.

Quote:

Originally Posted by audionewbieyao /img/forum/go_quote.gif Q: Suppose TI TPA6210 is capable of properly drive headphones up to 600ohm, such as HD600/HD650 etc., then was Xonar Essence STX properly designed to meet TPA6120's requirements in order to generate best performance?"

My next question if we can show that it really is all that would be: what's wrong with all the other amps and sound cards we've been buying until now?