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View Full Version : Which way to input the caiman



mike1210
30-11-2009, 22:11
Hello,
Bit of an odd question really. Just bought a Caiman (very happy with it) but was wondering the best way to connect my PC to it. Stan says on the website that Coaxial is the best way however I currently have 4 options

1. USB from PC to caiman

2. My onboard Digital Coax from a realtek ac 97 card (Asus P5B motherboard)

3. Digital Optical from onboard sound card

4. Digital Coax out from Focusrite Saffire external sound card, bear in mind this is external and connects to the PC via firewire cable

http://www.avalive.com/pimages/pimage_37323.jpg

I thought number 2 would prob be the best option but wasn't 100% sure. I know I can trial and error this but was wondering in theory am I right in saying option 2 is the best way:)

Themis
30-11-2009, 22:19
Number 2 seems to me the best option, too.

For quality USB output, you need something like this : http://theartofsound.net/forum/showthread.php?t=4667

lovejoy
01-12-2009, 08:18
I get better results using an optical connector. It's not night and day between optical and co-ax, but I definitely prefer the optical connection.

I believe the quality of the cable you're using has more bearing than the method of connection, although I find it quite reassuring that connecting a PC via optical means that you're not connecting the ground from the PC - which is always going to be very noisy - to the DAC.

My co-ax cable is an old Kontak Link 505 which cost me about £50 quite a few years ago now. Stan's optical costs less than half that and does the job very nicely in my system.

mike1210
06-12-2009, 18:08
I find it quite reassuring that connecting a PC via optical means that you're not connecting the ground from the PC - which is always going to be very noisy - to the DAC.


You may have a point there, when I play a DVD movie using the coax lead I get crazy noise going through the DAC, I think it's the transport that does it. I've ordered one of Stans optical leads to give a whirl. Cheers guys:)

Peter Galbavy
07-12-2009, 10:23
Are you sure that nots DD or DTS being sent to the DAC and it not understanding ?

leo
07-12-2009, 18:44
You may have a point there, when I play a DVD movie using the coax lead I get crazy noise going through the DAC, I think it's the transport that does it. I've ordered one of Stans optical leads to give a whirl. Cheers guys:)

Set your DVD player or sound card digital out to output PCM , if its set to DD it won't work

Kris
08-12-2009, 17:26
I don't know about the Asus P5B, but my P5Q has one of the best on board audio of any motherboard. (Realtek ALC1200).


I find it quite reassuring that connecting a PC via optical means that you're not connecting the ground from the PC - which is always going to be very noisy - to the DAC.

That's interesting. My Co-ax out is as clean as a whistle :confused:

mike1210
10-12-2009, 20:29
Are you sure that nots DD or DTS being sent to the DAC and it not understanding ?

I think youre right, the optical did the same thing, I can still make use of the leads though so not the end of the world

mike1210
13-12-2009, 18:13
Set your DVD player or sound card digital out to output PCM , if its set to DD it won't work

Thanks that fixed it in (win7) control panel > sound > playback > properties > supported formats

I unticked the options it couldn't decode now it works tidy:)

theone999
20-12-2009, 12:48
Number 2 seems to me the best option, too.

For quality USB output, you need something like this : http://theartofsound.net/forum/showthread.php?t=4667

you would spend an extra £100 to convert from one input method to another while the Caiman is perfectly capable of accepting both inputs in the first place ? :scratch:

Themis
20-12-2009, 13:53
you would spend an extra £100 to convert from one input method to another while the Caiman is perfectly capable of accepting both inputs in the first place ? :scratch:
Because isochronous adaptive usb is rather low-fi. ;)
And because the Caiman is limited on 16/48, too.

theone999
21-12-2009, 15:21
Because isochronous adaptive usb is rather low-fi. ;)
And because the Caiman is limited on 16/48, too.

yeah, but the HiFace is plugged into the USB socket nonetheless?? And so does my USB cable..:scratch:

purite audio
21-12-2009, 18:19
The hiface has two tiny crystal oscillator 'clocks' and a wee isolation transformer to separate it electrically, it is a clever little thing , and as Themis mentioned it enables you to play everything up to 24/192, if your dac is capable .
Keith.

Themis
21-12-2009, 18:47
yeah, but the HiFace is plugged into the USB socket nonetheless?? And so does my USB cable..:scratch:
The physical interface is not the limitation, as far as I know.
The limitation comes from the way the clock is transmitted and/or reconstructed (or not) and from the USB drivers used.
(I won't mention the clock used for S/PDIF or D/A conversion, which is still another matter, as Keith explains ;))

StanleyB
21-12-2009, 18:58
The question I ask myself is this: is 192KHz better in reproduction compared to the 64X oversampling of the Caiman?

At the same token, how many people have 192KHz audio files that they want to play back? And how many are limited to just USB as their interface to a DAC?

I would be hesitant to use USB for anything above 48KHz, in view of the claims and counter claims made about synchronous, asynchronous, and adaptive data transmission via USB. In the face of such unclear possibilities, my route would be coax or optical out direct from a PC or MAC.

The Creative Sound Blaster X-FI Notebook optical adapter is cheap at less than £50 and more reassuring than any USB solution if I am not mistaken. I got one as it is, and it performs quite well without me having to worry about async etc:).

Themis
21-12-2009, 19:06
I would be hesitant to use USB for anything above 48KHz, in view of the claims and counter claims made about synchronous, asynchronous, and adaptive data transmission via USB. In the face of such unclear possibilities, my route would be coax or optical out direct from a PC or MAC.
I completely agree. I will never use USB if my PC/MAC had S/PDIF. Never mind the sample rate. ;)

StanleyB
21-12-2009, 19:33
I wouldn't go so far as to say 'never'. As has been demonstrated by the TC-7520 and Caiman, it is possible to obtain outstanding audio performance from USB when using the standard PC, LINUX, of MAC drivers.
Where the problem arises is with the implementation of the USB method by the multitude of Chinese made DACs that have flooded the market in recent years. Poor understanding of the USB chip manufacturers datasheet has compounded the problem. Unfortunately, USB based DACs like the Keces ones have spread the problem even more widely.

Now there is the added problem of incorrect marketing info from some USB 'solution' providers.
I read the following marketing blurb on a foreign forum, attributed to a USB adapter:


Quote:
The reason why this has better jitter performance than many top end CD players is two fold - first it is purely designed to be a USB -> SPDIF converter and nothing else. Inside they have their own custom firmware running on a Xilinx chip running async USB. Plus instead of a PLL that every single other solution uses for the SPDIF clock, they use a super stable crystal oscillator.

It is this sort of marketing lies that damages the confidence of buyers.
I can only speak about my own products, in the absence of confirmed information from other DAC manufacturers. And what I can say is that I use a USB to SPDIF converter in my TC-7520 and Caiman, which is controlled by a dedicated crystal oscillator.
So any marketing suggestion from that company that they are the only ones using a crystal is completely false. However, no doubt many buyers have been suckered into swallowing those claims.

Themis
21-12-2009, 19:52
In practice, S/PDIF is more mature that USB Audio. Perhaps the differences are simply there.

Well, I don't understand (according to the marketing quote) what "S/PDIF PLL/oscillators" have to do with "async USB" (that I suppose mean Asynchronous Synchronization Type of -Isochronous- USB) ? It's a mystery to me.
They are two different things, as far as I know... :scratch:

StanleyB
21-12-2009, 19:55
That's what I thought, but that doesn't stop the marketing of the product trying to throw sand in the eyes of potential buyers.

purite audio
21-12-2009, 22:11
Where did that quote come from Stan, there are only two dacs that are async USB, Gordon Rankins 'Wavelength' series and the Ayre which licensed the deign from GR.
Keith.
'Reference recordings' HRX 24/176 are exceptionally good.