USB in ----> optical out

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owl37400

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I need something that will take a USB input from my computer and give me an optical (TOSLINK) output which will go to the hifi (more specifically, to a DACmagic 2 from Cambridge Audiio).

It seems that this will do the job:

http://www.maplin.co.uk/Module.aspx?ModuleNo=34128
a56ak.jpg



My question is, is it worth spending any more than the £20 that will cost? I'm thinking, it's a digital signal in, digital signal out, so it either works or it doesn't; there's no issue of sound quality being better with one adapter than another .... or is it not as simple as that?

If it's worth spending more, any recommendations?




(Have been using one of these up till now - http://www.guitarampkeyboard.com/en/behringer-uca202-usb/69494 but it's just died)
 
It seems like it should do the job. It has a USB input and an optical output. I'm using the following Terratec and quite happy with it.

http://www.amazon.co.uk/Terratec-Aureon-Dual-USB-Notebook/dp/B000WL23KC

I bought it about a week before Keith (Purite Audio) posted details about this :(. To rub salt into wounds, the price of the Terratec seems to have dropped, I'm sure I paid about twice the current asking price of £16.99.
 
I use one these maplin thingies. It works fine. I don't use it for critical listening, just to get the odd file off the computer into the hifi; also for internet radio, but there the bitrates will usually hide all sorts of other ills!
There must be better (and more expensive) solutions - the purité audio thing springs to mind. As always, it's horses for courses.
 
The m2tech hiface seems really good I had a chat with Keith from purite and am gunna try one when they come in this week, the dacmagic has a coax in im sure and the hiface will eliminate jitter more and give a better signal, he gives a money back guarantee too so its worth a try on coax. He also mentioned the new m2tech evo which should be an end of july product and that may be optical out I cant remember but if ur serious about pc related tunes it worth a look at and if ur not just go with what does the job.
 
eisenach said:
I use one these maplin thingies. It works fine. I don't use it for critical listening, just to get the odd file off the computer into the hifi; also for internet radio, but there the bitrates will usually hide all sorts of other ills!
There must be better (and more expensive) solutions - the purité audio thing springs to mind. As always, it's horses for courses.
Click to expand...

So am I misunderstanding something when I assume that if it's digital in and digital out, there ought not to be any signal degradation?
 
There are just different protocols for transferring data and some are better than others.
Keith.
 
Async firewire ,async usb and ethernet to not have an embedded timing signal, hence the dac clock is in sole control of the data flow, in a properly implemented design this produces extremely low interface jitter.
Keith.
 
"The main thing to keep in mind when reading about adaptive and asynchronous USB modes is clocking. Clocking is extremely important with digital audio. Many digital audio experts agree that keeping the clock as close to the DAC as possible, or using a master clock for all digital components is the way to achieve the most accurate sound. In consumer high-end audio as well as professional audio clocking is a major concern and very often external master clocks are used to achieve the best sound.
Asynchronous USB DACs are few and far between. Currently Ayre, Wavelength, and dCS are the major manufacturers with asynchronous products on the market. In my opinion the reason for this lack of async DACs is simply because it's very difficult implement this technology. There is a specific skill set required to implement asynchronous USB and it's not common place in high-end audio. Implementing async USB requires a manufacturer to write its own software for the TAS1020 chip and invest thousands of hours on this part of the DAC alone. The limited number of manufacturers who've decided to take on this task instead of going with a plug n' play chip are doing it because they think the performance gains far outweigh the development pain.
Asynchronous USB essentially turns the computer into a slave device as opposed to adaptive USB which does the opposite. Thus, an asynchronous USB DAC has total control over the timing of the audio. One very important feature of asynchronous USB mode is bidirectional communication between the computer and the DAC. The computer sends audio and the DAC sends commands or instructions for the computer to follow. For example the computer's clock becomes less accurate over a given period of time and can send too much data too quickly and fill up the buffer. Asynchronous DACs will instruct the computer to slow down, thus avoiding any negative effects of a full, or empty, buffer which can manifest itself into audible dropouts and pops or clicks. According to Wavelength Audio the tail is no longer wagging the dog when using asynchronous USB mode. Plus all of this is done without additional device drivers or software installation."
 
If you actually look at the results of jitter on the output they are extremely small even from equipment considered pretty bad by todays standards. Sideband spikes at around -100dB for example will be very strongly masked because of their extreme proximity to the main tone.

It seems to me that jitter is way over-hyped.
 
Yet in my comparisons here, I much prefer async devices whether they are USB or firewire , obviously data transfer is only factor in the design of a good dac.
Keith.
 
There must be a difference even though on paper it mays seems small, in actual sound production it has been reported by so many credible inedependants to be so. Im gunna check to see if my Valab is async cos its bloody good, will report back......
 
Dan me neither, but as your quote correctly says, there are only a few Async USB implementations on the market at the moment,although I have noticed an increasing number throw 'async'around in their marketing.
Keith.
 

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