Favorite USB to audio decoder?

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This one.
 

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Made after reading this. Good to know that some still have high standards. Like obtaining 0.002% thd and a stable clock.

http://www.planetanalog.com/showArticle.jhtml?articleID=12801995

Built around pcm2702. Schematics taken from TI's demo board (DEM-PCM2702 - search for it on www.ti.com). The pcb is my attempt at learning a little eagle.

For those interested there is also the pcm290x family which adds features like spdif in/out and analog in.

Chips can be obtained as free samples from TI. But you better have a hot air station to solder them.

This one is with non-audiophile parts (only on the analog part resistors are 1% and capacitors matched with a multimeter) and usb-powered.

Still it sounds stunning for it's price.

Of course if you can afford it TI sells a complete demo board for several times the price it costs to diy.
 
http://www.lashen.com/vendors/CooperTools/Weller_high_end.asp

smd's and small package ic's are soldered not with the classical soldering station but with a thing that has a tip with a hole that blows hot air. You don't touch the chip, just heat the pins until solder melts.

(pcm2702 comes in ssop28 package meaning pins are spaced at 0.65mm - now this is a little tight - should have made the picture near a familiar-size object)
 
ozone_stink said:
How did you cut the top off the wood block and still maintain the alignment...looks perfect.

There is a bit more on the construction of the box at http://www.ecp.cc/ra1.html I didn't do anything special. Just cut the blocks on a table saw and used a forstener drill bit in a drill press to hollow them out. Actually, the fist time around I used a regular drill bit and then a dremel which was very unpleasant work. When I replaced the original dac with the larger NOS dac, I used a forstener bit which was much easier.

I actually like this method a lot as I am not so good at joinery. I am plannig to use it for a larger amp one of these days -- though large enough blocks of wood can be hard to find and cost a mint.

-d
 
Yes, it is.

BTW: I once asked and they told me that the photo doesn't reflect reality. The real thing has a 3.5mm jack for the output, and a jumper for power supply selection, all in 59x28mm.
The one in the photo doesn't have the jack, if you look at it carefully.

That adds some value...

I think I will order one to include it inside my coldamp amplifier as another input option (XLR, RCA, USB... cooool) :D
 
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