I just made three boards last night based on the TI PCM2707. Didn't get a chance to test them out, but the design is pretty straightforward. I just used the datasheet design and parts from my junk boxes, but you could do this from scratch for probably under $30. Output is 3v SPDIF, but that's easy enough to convert to optical ($1.50 TOSLINK transmitter), TTL, or balanced with a transformer.
i did search but found nothing, now i surfer digital section and on the same page i found 
I am not in digital DIY, if anyone can recomend complete product or have for sale it would be great. I will use it on my sony vaio TT notebook.it have only usb and firewire outputs.. are theese self powered (via usb) or need separate?
how theese coverters comapre to transports like krell md2 and similar?
I am not in digital DIY, if anyone can recomend complete product or have for sale it would be great. I will use it on my sony vaio TT notebook.it have only usb and firewire outputs.. are theese self powered (via usb) or need separate?
how theese coverters comapre to transports like krell md2 and similar?
Anything self-powered is crap. Anything using isochronous transfer is crap. Anything without proper transformer coupled 75ohm output is crap. Not sure whether this leaves much. Converting from one compromised audio protocol to another can hardly be spectacular. Unless you find a way to reclock and not rely on recovered clock at all.
so what do you recomend? can you direct me to some supliers or maybe you have for sale?
I will use it as a second source. times goes by and I feel myself that sometimes its just better to have pc as a source especialy when tuning speakers xover and changing track by track.its way much quicker than cd transport which can have only one cd disc.
I will use it as a second source. times goes by and I feel myself that sometimes its just better to have pc as a source especialy when tuning speakers xover and changing track by track.its way much quicker than cd transport which can have only one cd disc.
What worked for me after trying a lot was to forget about spdif and just use USB-to-I2S. As async chips are not easy to use and jitter with the 27xx is a real problem i chose a 2707 followed by an ASRC with a stable local clock. Controversial? Very. But works for me quite well. Then again i don't have a Krell to compete with
Ideally my choice would be Wavelenght's audio USB solution.
Ideally my choice would be Wavelenght's audio USB solution.
I just sold my P700 transport as a PC has been my only digital source over the last two years. Nothing will persuade me to own a cdp again. Keeping a few thousand CDs? No, thanks, i have enough LPs as is.
Keep in mind USB audio is not an easy out of the box solution no matter what dac you buy. PCs sound disconcertingly different due to all sort of reasons, both software and hardware related. For some reason i am not very lucky with notebook computers. Out of the three i've tried none could compare in sound to my desktop.
Keep in mind USB audio is not an easy out of the box solution no matter what dac you buy. PCs sound disconcertingly different due to all sort of reasons, both software and hardware related. For some reason i am not very lucky with notebook computers. Out of the three i've tried none could compare in sound to my desktop.
Gordon @ Wavelength has developed probably the best asynchronous USB interface design currently available. He has posted about this in other forums.
http://www.usbdacs.com/Products/Products.html
Unfortunately you can't buy a standalone USB-to-anything interface from Wavelength.
While this definitely wont meet analog-sa's exacting standards, the HagUSB interface is worth a look. It's limited to 24bit/48khz. There is also a schematic there.
http://www.usbdacs.com/Products/Products.html
Unfortunately you can't buy a standalone USB-to-anything interface from Wavelength.
While this definitely wont meet analog-sa's exacting standards, the HagUSB interface is worth a look. It's limited to 24bit/48khz. There is also a schematic there.
I think we are threadjacking. There is a spdif converter over on TwistedPear 's website. I think they have the schematic and BOM listed as well. They are sold out of boards but doesnt look like you were worried about a board anyway.
Wavelength is easy to get excited about, sorry for threadjack.
Uriah
Wavelength is easy to get excited about, sorry for threadjack.
Uriah
thanks anyone, I will check this out.
as for quality I dont expect maximum quality, i still will be sticked with cd turnable for a while. actualy at my neighboard Vilmantas (www.lessloss.com) I have seen some seriuos pc cards tunings (looks amazing- 4 extra stage builded on card and it have only i2s outputs ) and whole pc builded from scrach to ensure purest digital signal. I think one day i will moove to this, but at that time I also probaly will moove to digital xovers also.
as for quality I dont expect maximum quality, i still will be sticked with cd turnable for a while. actualy at my neighboard Vilmantas (www.lessloss.com) I have seen some seriuos pc cards tunings (looks amazing- 4 extra stage builded on card and it have only i2s outputs ) and whole pc builded from scrach to ensure purest digital signal. I think one day i will moove to this, but at that time I also probaly will moove to digital xovers also.
If you can be satisfied with Toslink, the ADSTech "Instant Music" RDX-150 has Toslink in and out. C/P from my post at MP3car:
"I bought an RDX-150 on sale at Staples and had a look inside. The USB codec is a Burr-Brown/TI PCM2902E. Build quality looks pretty good (made in Taiwan, not China); the other chips are all major brands. It's got low-pass filters on the analog inputs and outputs, just like the evaluation board that TI sells for the PCM2902. There's an unpopulated connector location on the board that appears to go to the input pins on the PCM2902 for HID key inputs for vol up/down and mute, which might come in handy for a car pc or other embedded application."
According to these Rightmark tests, the ADSTech performs a lot better than the Behringer UCA202 that is based on the same chip.
For the price it's worth buying to modify; there's plenty of room in the case (and PC board) to add stuff like an RCA out.
"I bought an RDX-150 on sale at Staples and had a look inside. The USB codec is a Burr-Brown/TI PCM2902E. Build quality looks pretty good (made in Taiwan, not China); the other chips are all major brands. It's got low-pass filters on the analog inputs and outputs, just like the evaluation board that TI sells for the PCM2902. There's an unpopulated connector location on the board that appears to go to the input pins on the PCM2902 for HID key inputs for vol up/down and mute, which might come in handy for a car pc or other embedded application."
According to these Rightmark tests, the ADSTech performs a lot better than the Behringer UCA202 that is based on the same chip.
For the price it's worth buying to modify; there's plenty of room in the case (and PC board) to add stuff like an RCA out.
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