[cobaltmute]

Quote:

Well im a procrastinator.  I have a rev R1 grub that i finaly found a use for.  However looks like 4 revs happened while i was gone.  Is there anything i need to do before i finish soldering it?  The new rev doesnt use a bipolar crystal.  Looks like the only real change is psel/fsel was connected to ground, now psel/test is connected to vdd, i dont know if i can do that mod.

 
If you have an original rev 1 board, you should be perfectly fine with the BOM/etc as was originally posted.
 
 

 

[Insighter]

I've made and combine RMAA measurements using SB Live 5.1 and SB Live 24 and can say that:
 
THD is around 0.0031% (-90dB, better than in datasheet) or less
IMD+noise is around 0.0064% or less
S/N ratio is -100dB, or better, and noise floor is very clean (Murata beads do their job well )

 
[size=x-small]Measurements must be done at max volume (otherwise additional distortion would be). [/size]
[size=x-small][size=x-small]Howewer, it can overdrive input, better to use attenuator or good headamp with volume regulation.[/size][/size]
 
So, specs better than AlienDAC and BantamDAC have.

 

[dhaninugraha]

my kit has arrived! yay! ordered them from beezar.com on 8/8 and the local post office sent me a pickup notice yesterday. picked the package up this morning. almost a month (first-class mail, oh well), but it was worth the wait. kudos to tomb for the swift service and overkill packaging!

time to get myself a new helping hand, and if the planets all line up, spare the weekend for another all-nighter. this is going to be fun.

 

[Beftus]

Listening to Return of the Headhunters right now with my GrubDAC feeding my 12AU7 Starving Student. What a great sounding setup.
 
Good luck assembling your GrubDAC, it's a bit fiddly to make but once you've got it working you are rewarded with a very fine DAC.

 

[dhaninugraha]

the itch was irresistible, so I built the grubDAC last Sunday. took me around 3hrs (it was my first time doing a project with so much SMT parts), and it immediately worked the first time I plugged it into my MacBook. pictures will follow.

will have to come home sometime this week, as I am intrigued about how it's going to sound combined with the WA6.

 

[funkydude079]

Is it possible to swap the mini usb port with a micro usb port?

 

[jdkJake]

Is it possible to swap the mini usb port with a micro usb port?

The mini-b USB connector is pin compatible with a micro-b connector.

Now finding a part that fits the same PCB form factor may be more difficult. But, perhaps not, I have not looked,

 

[cobaltmute]

The mini-b USB connector is pin compatible with a micro-b connector.

Now finding a part that fits the same PCB form factor may be more difficult. But, perhaps not, I have not looked,

This may be difficult. Last I looked most of the Micro-USB connectors were surface mount.

 

[funkydude079]

I just finished making my grubdac but I'm not getting any sound. When I plug it in my computer, I can see it. I'm getting 3.26 V when I measure from 0 to the 3V3. Does anyone know what the problem is?

 

[jdkJake]

How about some pictures of the top and bottom of the board?

Lots of light and as much focus as you can muster.

 

[funkydude079]

Are these photos ok?

 

[jdkJake]

The middle photo (top of the board) needs to be in better focus. If your camera has a macro mode, now is the time to use it.
 
The third picture helps a lot, but, we still need a better shot of the top. Especially of parts U1 and U3. 

 

[hitman47]

Quote:

Are these photos ok?

That looks like a huge bridge on the smaller chip there, you should fix that and try again
 

 

[funkydude079]

Thanks for the advice. I'm going to be pretty busy for the next few days so I probably can't try anything until like thursday or friday. I'll definitely try taking a closer look at the smaller chip and getting better pictures up.

 

[lehtinel]

Started building mine today, a hassle for a first timer to get a bridgeless solder for the PCM chip. I completed the build and fired it up. Now the TPS chip gets super hot, I havet had the DAC on for more than 10-20sec. so I would not fry anything. Tried solering the TPS againg mut that didn't help.

Pictures to come.