XXHighEnd

Ultimate Audio Playback => Your questions about the PC -> DAC route => Topic started by: AudioFool on March 14, 2013, 10:45:12 am



Title: New HTPC build: usb asynchronous or spdif coaxial?
Post by: AudioFool on March 14, 2013, 10:45:12 am
Hi,

I'm planning a rebuild of my htpc only for playing music.

Spec:
-Intel I7 920
- Asus P6T
- 6 Gb Mushkin 1600mhz 6-7-6-18
- 1x Velorap 300Gb
- 2x Samsung HDD sataII 600Gb
- Windows 7 Ultimate Sp1
- Antec 850w Truepower psu
- Graphics Asus G 210 fanless hdmi+dvi

The music will be played by the XXHigend Player

About the output to the DAC, I've some considerations to make.

1. Coaxial spdif output of the EMU 1212m PCIe to a Berensford Bushmaster

or

2. Asynchronous usb to a Musical Fidelity M1 DAC.


Some advice is appreciated about the 2 options for output.

Fwiw, great site and sorry for the bad English, it's not my native language.

Gr

Ed





Title: Re: New HTPC build: usb asynchronous or spdif coaxial?
Post by: PeterSt on March 14, 2013, 01:19:30 pm
Hi Ed - welcome here.

Well, too difficult to tell without the real listening experience;
Both manufacturers show specs which won't be met in the first place (but more nice would be : which are equal-ish anyway), so from there I won't be able to decide.

Coax should be worse than asynch USB were it for jitter, and no way I see "jitter rejection of (?) 50ps" to be true for any SPDIF connection.
Asynch USB should not carry jitter, but the first asynch USB with good jitter specs is still to be seen (by me). So, 25ps ? haha. So, asynch USB *creates* jitter. Now what.

With this as some useless reference, the Music Fidelity does 24/96 over USB only. So be careful for that when you want to choose for asynch USB but wish 24/192 at the same time (and notice that the specs are written such that it even could be limited to 16/96, but I don't really think that is the case).

What I would do ? Buy the M1 and find you and two others to obtain an XXHighEnd license and buy the Bushmaster as well. That is, if I understood the prices right. IOW, not the biggest deal and you can try forever.

Regards,
Peter


PS: I see no video card in your HTPC, but unless it will be a 600W consuming one, your 850W PSU seems a bit overdone ?
Get the cheapest passively cooled video card you can find these days (25 euros ?) which will do fine for everything and a 350W PSU will be OK.


Title: Re: New HTPC build: usb asynchronous or spdif coaxial?
Post by: AudioFool on March 14, 2013, 02:03:02 pm
Hi Peter,

Thanks for your comments.


The Musical Fidelity M1 DAC is updated to a new version which allows 24bit/196Khz over a-synch USB! This in mind I will go for the M1 Dac so I can upgrade in the future using usb.

Further, the computer specs are components I already own. The GPU is a Asus G210 fanless.

Greetings,

Ed


Title: Re: New HTPC build: usb asynchronous or spdif coaxial?
Post by: AudioFool on March 14, 2013, 02:11:08 pm
Hi Peter,

I was wrong , usb of the MF is 24/96  :blush2:

Gr,

Ed


Title: Re: New HTPC build: usb asynchronous or spdif coaxial?
Post by: PeterSt on March 14, 2013, 02:23:06 pm
:naughty:

Tried to find a proper smiley for this. But I don't think it exists ...


Title: Re: New HTPC build: usb asynchronous or spdif coaxial?
Post by: AudioFool on March 15, 2013, 01:24:05 pm
Hi,

For my understanding, why is it preferred to have a 24bit/196khz input or better on usb for a DAC while oversampling is not desired?
Most of all, I will play back Flac/WAV in 16bit/44,1Khz format with the XXHE player.

Ed

Ps. Is it possible to change drivers so the dac will except 24/196 on usb like the Cambridge driver do?


Title: Re: New HTPC build: usb asynchronous or spdif coaxial?
Post by: PeterSt on March 15, 2013, 02:29:29 pm
Hi again Ed,

Quote
Ps. Is it possible to change drivers so the dac will except 24/196 on usb like the Cambridge driver do?

That is really for you to find out. Often USB Asynch drivers origine from the same source, but it is also hardware (receiving chips etc.) dependend.

Quote
For my understanding, why is it preferred to have a 24bit/196khz input or better on usb for a DAC while oversampling is not desired?
Most of all, I will play back Flac/WAV in 16bit/44,1Khz format with the XXHE player.

This is a bit tricky. "Your" reason would be that everybody (almost without exception) uses Arc Prediction Upsampling and this is not because I told anyone - it was made for the Phasure NOS1, while still everybody started to use it. So, it must sound better for everyone. And thus for you too.
Next, the higher the upsampling rate the better it is.

But it is and stays up to you and your own ears. At least you have a theoretical reason now ... :)

Regards,
Peter


Title: Re: New HTPC build: usb asynchronous or spdif coaxial?
Post by: AudioFool on March 18, 2013, 12:26:12 pm
Hi,

I found a nice DAC with a input of 32bit/192Khz and even 32/384. The chip used is a VIA Envy VT1731. The output of the dac is 10 Ohm / 5V XLR.

1. Can I skip the Pre-amplifier and use the volumecontrol of XXHE?
2. Can I use Arc Prediction with this DAC?

Thanks,

Edward


Title: Re: New HTPC build: usb asynchronous or spdif coaxial?
Post by: PeterSt on March 18, 2013, 01:29:44 pm
Hey Edward,

Yes and Yes (although I know of designs which claim to be close to 0 Ohm output impedance and still won't drive a thing).

Whether Arc Prediction works out for the better is always to try, but usually it does. This is not by guarantee because it depends on how much the filtering in the DAC will be overruled (automatically).

But be careful. The VT1731 is a receiver/controller chip and it is nothing like a D/A chip. So, it will be able to receive 32/384 - pass that on to i2s (which is an in-DAC protocol) but for example will output at 24/192 only when it outputs SPDIF (not that you will be able to judge well what this means for "your DAC"). Anyway, don't make the mistake of looking at the chip's specs to next think that "your DAC" will be able to work with that / at that rate.

Regards,
Peter


Title: Re: New HTPC build: usb asynchronous or spdif coaxial?
Post by: AudioFool on March 18, 2013, 02:04:39 pm
Hi Peter,

Thanks for your comments! The DAC is a Audio GD NFB-1.32 with ES9018 converters or the Reference 5-32 with PCM1704UK converters. All this over usb connection.

Regards,

Edward