does a soundcard change the bits?

[manisandher]

Hi Everyone,

I'd like to share the findings of a protracted listening session I had last night and early this morning (my wife is away for the weekend, so I just had to take the opportunity).

My intention was two-fold:

1) to identify the difference the Mem box makes
2) to decide whether upsampling helps or not

All listening last night was done with 0.9u-11. This morning, with 0.9u-12. I was using system 1) in my signature.

But things didn't quite work out as I was expecting or hoping... 'The best laid plans of mice and men' and all that...

You see, I wanted to start by making a definitive comparison between XXHE and my Esoteric P70 transport... to convince myself that PC audio really is the way to go. To make the comparison fair, I burned an HDCD-encoded album onto a blank CD (black with bevelled edges) using Yamaha's 'Audio Master Quality' function. This should have eliminated any effects that EAC might have introduced during the extraction process vs. the standard CD.

But I couldn't get my D70 DAC to recognize the HDCD content from XXHE. So, I connected my transport to the soundcard via AES/EBU and started playing around with the soundcard's mixer software. Finally, I got the DAC to recognize HDCD from the transport via the soundcard (I needed to play around with a couple of pots in CueMix, MOTU's mixer software). HDCD from XXHE worked fine also after that.

But I had a real shock when I disconnected the transport from the soundcard and plugged it directly into the DAC again. It sounded better than when fed to the DAC via the soundcard.

I assumed that the MOTU was affecting the sound, so I brought down my RME FF800. Again, I had to play around with FF800’s mixer software to get HDCD to work (I had to decrease the output by exactly 1.0 dB in Fireface Mixer). But when I did, the result was exactly the same. The transport sounded better plugged directly into the DAC. (I was careful to reduce the DAC output by 1.0 dB when listening to the transport to make the comparison fair.)

Via either of my two soundcards, the transport sounded flat and lacking in dynamics compared to being connected directly to the DAC. Theoretically, with the soundcard slaved to the DAC, this should not have been the case.

The only conclusion I can make is that the soundcard’s hardware and/or mixer software is/are having a detrimental effect on the sound. I mean, could anyone explain to me why I should have to play around with the soundcard’s mixer to get HDCD to work? It should work with everything set to zero, no?... unless the hardware and/or software are interfering with the bits.

And even worse...

... whatever the soundcard’s hardware and/or mixer software is/are doing to an AES/EBU feed from the transport, it/they seem to be doing to XXHE (or any other software player I tried). I heard the same distinctive ‘veil’ over the music as I did playing the transport through the soundcard. And this is worrying.

I’d love to hear your thoughts on this.

(FWIW, I did manage to get some answers to my original questions, which I will post separately.)

Mani.

[RX1]

I might be a bit slow, so could you please tell me - are your main worry what ever happend to your soundcard or that your Esoteric transport sounds better than PC? :-)

Rolf

[edward]

... whatever the soundcard’s hardware and/or mixer software is/are doing to an AES/EBU feed from the transport, it/they seem to be doing to XXHE (or any other software player I tried). I heard the same distinctive ‘veil’ over the music as I did playing the transport through the soundcard. And this is worrying.

I’d love to hear your thoughts on this.

Although I do feel the soundcard and XXHE can make a difference, IMHO having a great piece of software like XXHE or even the best soundcard money can buy is not always enough. The PC itself can have as big a difference (if not bigger) on the SQ as the software and soundcard can have. I built a very purpose built PC this year with very specific choices in CPU, Memory, Motherboard, etc. as well as making very specific settings in Vista (such as disabling services, etc.) and IME this has all made a difference in SQ. Compared to my other "work" PC, the difference in SQ is significant.

I wonder, Mani, if you notice a difference between your two PCs.

The biggest culprit is the Power Supply. (And this is where your CD player has a distinct advantage). I have not compared to a laptop, and I chose to build a desktop because I have more versatility in changing things like BIOS settings. But I noticed a big improvement just changing the power chord. And recently I was experimenting powering the PC with a battery backup (UPS) and when I unplug the UPS from the wall and run it off battery power, I hear a significant increase in SQ. So, presumably a laptop would have an edge here over a desktop, but there were so many specific hardware settings that I made that cannot be done on a laptop (AFAIK). So it's a tradeoff. If we can just get a desktop PC to run on battery, then that is the Golden Egg.

[manisandher]

I might be a bit slow, so could you please tell me - are your main worry what ever happend to your soundcard or that your Esoteric transport sounds better than PC? :-)

Rolf

Rolf,

My main worry is that the soundcard (hardware and/or mixer software, I don't know) is detemining the ultimate SQ and that there is nothing we (or XXHE) can do about it. Theoretically, taking the spdif output from the soundcard and slaving it to a high-quality DAC should be all that's required. But I'm hearing differently...

Mani.

[manisandher]

The PC itself can have as big a difference (if not bigger) on the SQ as the software and soundcard can have.

Hi Edward,

I'm sure you're right, though I haven't compared my two PCs... yet. (I might have to wait until my wife's out of town again )

At least we can do something about optimising our PCs, in much the way you describe (thanks BTW). I know that Peter believes the firewire PCI card is really important when using an external firewire soundcard.

But what can we do if our soundcards are manipulating our beloved data?

Mani.

[xp9433]

Mani

I just read about improvements in sound from upgrading:
RME Fireface 400 firmware upgraded to version 1.66 dated 02/25/2007
RME Fireface driver upgraded to 2.86 dated 03/04/2008

over at http://www.audioasylum.com/cgi/vt.mpl?f=pcaudio&m=30553

Frank

[manisandher]

Hi Frank,

I've heard improvements from updating drivers before. FYI, I was using 2.8.6 on this occasion.

Mani.

[PeterSt]

Hi Mani,

First of all, thanks for a good read during my Sunday morning coffee.

Then, does a soundcard change the bits ? yes, of course it does when you digitally attenuate with 1dB !
The mistake you probably made is that where XXHighEnd allows for digital attenuation, you thought you can do it with general digital pots ?

Wonder o wonder, the digital volume in XX does *not* change the bits, although you'll loose some (which latter by itself happens with all digital volumes).
And keep in mind : there is no way it is allowed to let a normal digital volume loose on 16 bit material.
Also not to forget, is my stating that the digital volume from XX makes SQ *better*, which by now (since the Release Notes concerned) people may have forgotten, or don't dare to use with the pre-amp out of the way (but there's always the combination including the pre-amp) ... so be careful what you actually compare.

I think this is sufficient to answer your question, and testing this is easy : listen through e.g. the Fireface with XXHE at -0dB and the Fireface at -6dB, and the other way around. The other way around should win, and the first gives this veil (I just recognize that).


What interests me though, is how you came about the exact -1.0dB setting getting things to work with HDCD. This hardly can have been a guessing means ...

Then, parts of your enthusiasm may have forgotton your original objectives (mentioned under 1) and 2) which somehow ran into playing HDCD encoded CD's which may be normal to you because of the D70 being able to decode even with XX playing (??), but which obviously (??) confused your setup and objectives. Or ?
Or IOW, why use a HDCD for this ?

Also, both feet on the ground, I think everybody knows that soundcards make a difference. No need to work that out, and no need to improve this for your test (generally, yes of course). IOW, your test would be about things including soundcards making a difference (hence deteriorate), because it is just about this. Is the P70/D70 better than XXHighEnd/D70 ? which just includes all needed for playback. If the P70 wins, then it be so. If you don't want that, start tweaking the PC side.

Of course you knew all this. But maybe you didn't realize that the comparison wasn't done right ...

To be ahead of things ... be prepared for hearing other things than, say, two months ago with less experience. So, indeed your P70 might win. But if it does, I tell you this (which I apparently do anyway, hahaha) :

I have been listening through the Fireface as DAC the last days in order to get 192000 etc. alive. This was the first time I had to listen through the Fireface somewhat more seriously, because 192000 too must sound good throug XX (mind you, this is different from testing Quad for which I need the FF just the same, and which is about apples and oranges always because I just don't listen to native 44.1/16 through the FF and can't compare anyway). So, native 192000 (which just exists) sounded with a special character to me, and actually I liked it. More liquid, more liquid bass especially. So ...

So yesterday I though to spend a whole evening listening through the FF with 44.1/16, but couldn't stand more than one track really. No pepper, no salt, no tapping feet, no nothing. So I thought "what the h*ll" and changed back to the nos DAC. Wow, what a difference does that make.

What is the message here ?
Well, actually something I didn't know myself; The differences have become so huge between oversampling and non oversampling, that I may wonder what you oversampling guys actually perceive. You may know that I always liked nos, but you *must* know that I, say, tune XX around that. I mean, I only listen through nos. And, what may improve on nos, may not make a difference on os. I just don't know.

So Mani, just in case the P70 will win the contest afterall, do not forget to rent an nos DAC and try that briefly.
My P1 (+ Audio Note) lost two years ago ...

[PeterSt]

I just read about improvements in sound from upgrading:
RME Fireface 400 firmware upgraded to version 1.66 dated 02/25/2007
RME Fireface driver upgraded to 2.86 dated 03/04/2008

over at http://www.audioasylum.com/cgi/vt.mpl?f=pcaudio&m=30553

By my own experience it is true that for the Fireface SQ may be influenced by their drivers. Therefore I *DO NOT* change to the newest versions when they become available. If there's anything that sneakes into your system for the worse (hence without ever noticing it, and then never being able to find the culprit), it is this. IOW, once you are satisfied, don't change !

FWIW : I am using driver version 2.82, firmware Dec 6 2007.

[manisandher]

you thought you can do it with general digital pots ?

What interests me though, is how you came about the exact -1.0dB setting getting things to work with HDCD. This hardly can have been a guessing means ...

Or IOW, why use a HDCD for this ?

Peter, I used HDCD for the test because I wanted to ensure that the data reaching my DAC via 1) the transport and 2) the soundcard was identical.

I had no choice but to use the mixer pots, in order to get an HDCD signal to be recognized by the DAC.

With the MOTU, there was no attenuation required - I just needed to shift the L/R panpots to their maximum positions. WIth the RME, I needed an exact 1.0dB attenuation - attenuating by 0.9dB or 1.1dB switched the HDCD processing off. When XXHE allows me to attenuate by this level, I'll try it.

BTW, this was done by testing and experimentation...

Mani

[manisandher]

So yesterday I though to spend a whole evening listening through the FF with 44.1/16, but couldn't stand more than one track really. No pepper, no salt, no tapping feet, no nothing. So I thought "what the h*ll" and changed back to the nos DAC. Wow, what a difference does that make.

Just to be clear here Peter, on this occasion, I never listened to the RME (or the MOTU). I just used them to send an spdif signal to the DAC.

When I have compared, the D70 trounces both of them...

Mani.

[manisandher]

Then, parts of your enthusiasm may have forgotton your original objectives

More amazement than enthusiasm... There should have been no difference, and yet there was.

For me, sorting this out seems to be at least as important as tweaking the PC or XXHE.

Mani.

[PeterSt]

There should have been no difference, and yet there was.

Maybe I misunderstand or misinterpret, but if this is about the comparison with (passing through) soundcard and without, why do you think there shouldn't be a difference ?
I'd say everybody knows that soundcards (at passing through) just make a difference. Try your mobo's chippy.

Do I misunderstand ?

[manisandher]

With the DAC acting as Master clock and the soundcard slaved to it???

Mani.

[manisandher]

I mean, I only listen through nos.

Peter, do you use the FF800 to send an spdif signal to the nos DAC, or are you using usb?

Mani.

[PeterSt]

With the DAC acting as Master clock and the soundcard slaved to it???

Right. That one I missed (in my context, not in your story).

To be honest, I don't know. Few people will be able to do that, and in here you are probably the only one doing that.
Must the answer be Yes then ? anyway, IMO you should do the test with a normal CD to avoid possible other anomalies.

Hmm ...

[PeterSt]

I mean, I only listen through nos.

Peter, do you use the FF800 to send an spdif signal to the nos DAC, or are you using usb?

SPDIF.
I can use USB as well, which is in the DAC converted to SPDIF before going to the chips, and it sounds way different (and far from better). Whether this is related to the FF reclocking I don't know.

Probably more things are going on, and reading the net it looks like more people come to the conclusion that USB is not Walhalla in those cases where a choice is possible.
Anyway, and as I said more often before, in almost all cases it is impossible to compare, because things just cannot be compared. For example, if the FF could take USB (in and out), I myself would already be much closer to an honest comparison.
Or, if my DAC would have I2S internally, and both SPDIF and USB would convert directly to that, the same.

I am fairly sure that - with enough people hence equipment - around, we could find the absolute best connection, and the connection will show a nature by itself. Actually this is what I created this board for.
But it really takes many more people.

It's already good that now ONE person is around who can slave his soundcard to the DAC. Didn't know that ...

Must think about this ...
If you, in the mean time, have more input to this, I'm very glad to get your opinions. Everybody would.
It is the most interesting anyway.

Peter

[manisandher]

Yes, I will repeat the test with a non-HDCD CD at some point. It will be interesting to see if the veiling is there or not with everything set to zero in the mixer (including L/R pans).

But the biggest question that remains on my mind is why the soundcard is changing the data in the first place. And it must be because my DAC doesn't register the HDCD signal with everything set to zero in its mixer.

I can undo any changes that the soundcard is making by changing settings in the mixer. This allows the HDCD signal to be detected... but does this really fix the problem or introduce the veiling effect?

One really important point here is that this has nothing to do with the PC or XXHE. This is purely to do with my transport, soundcard and DAC. The PC is merely being used to change the mixer settings. But the mixer sits in the soundcard (i.e. the soundcard can be used as a standalone unit).

WRT slaving the soundcard to the DAC, what can I say? I would never buy a DAC where I could not do this.

My DAC allows three different settings: 1) PLL, 2) RAM buffer and 3) Wordclock + RAM.

Setting 3) turns the DAC into the Master, with the clock sitting right next to the four PCM1704 dacs. And there is simply no comparison.

Mani.

[manisandher]

Then, parts of your enthusiasm may have forgotton your original objectives (mentioned under 1) and 2)

See http://www.phasure.com/index.php?topic=481.0

Mani.

[PeterSt]

Yeah, I read that first this morning. Already forgot that this "story" was in a separate topic.

(FWIW, I did manage to get some answers to my original questions, which I will post separately.)

Even that didn't trigger my sleepy head.
Coffee was good though.

For the remainder, I guess it is too difficult for at least me to comprehend what you can exactly do with your settings, how your soundcard mixer should or should not influence your DAC, how the soundcard can play offline (I understand this) while mixer settings influence playback, combined with the soundcard slaved to the DAC but the DAC (D70) should produce the sound.


The only conclusion which seems logical to me would be that you use the soundcard as the DAC in this slaved situation (the P70 playing). But since you will not be doing this ... as said, I just can't comprehend.