DCAudioDIY.com

After hearing the little DAC that Rich of HAL fame brought to the show last summer, I decided to try one. Being cheap, I didn't buy the $100 Amanero USB to I2S board. Bought a cheaper one from DIYINHK.

Used what I had on hand to connect it up before, committing it to an enclosure.

Had a devil of a time getting a Windows laptop to read my music drive, external HDD formatted by Linux. Windows wouldn't assign the drive letter to the drive. Found a simple and free program that works right off the bat.

Then, the driver for the DIYINHK would not load. Turns out, the driver they sent to me was infected. Norton caught it.

Rich pointed out that for $9, DIYINHK had another driver. Bought it, loaded and worked in an instant!

Actually, it worked for about five minutes. Then the dog heard something and charged right through the USB cord from the laptop on the coffee table to the DAC on the rack! She tore the USB connector half way off of the board.

I scavenged an old scanner for a new connector and it's working again. Got lucky.

Sounds pretty good. Still early, but I think it sounds better than my China LITE DAC50. The DAC50 doesn't have a USB input, so I've been using a HagUSB as an interface from USB to S/PDIF, then a Monarchy DIP to reclock and convert to AES/EBU (balanced) into the DAC. The new setup certainly is simpler.

When it goes into a box, I will remote connect a higher quality pair of RCA connectors. Then, experiment with chip/cap options.

All in all, well worth the minimal effort!

Pics to follow. Need to reduce size, as I'm typing this on my phone.

Thanks Rich/HAL!

Pics

What is the power supply? It almost looks like a switcher...

Two transformers. Just need 25.2VAC CT and 9VAC to the linear supplies on the AK4490 DAC board.

Is there a schematic somewhere available for the DAC?

I'm interested in the possibility of building an analog stage off board. Not much room for good caps, etc. On the board.

Not that I know of. Probably just download the AKM AK4490 datasheet and look at the recommended design. Probably close.

http://www.akm.com/akm/en/file/datasheet/AK4490EQ.pdf

Yea, did that.

Looking at pages 62 and 63, seems like they are using example 40 for PCM judging by the parts count. But how do they switch to example 42 for DSD? Or do they?

Also,since the DAC output is balanced,I was contemplating a balanced audio signal out. ......

They probably just use figure 40 for both PCM and DSD and forget about the one pole in the filter. You also have to switch the input I2S Bus wiring for DSD to other pins on my USB interface, so more than just the filter changes.

Thanks. That's what I thought. I'll probably just build the first version. Ordered a new board, just in case I screw one up (Not that that ever happens)