[sfogar]

Hi,
 
they shipped it to me on 19th of May 2011...
 
My (very) last test (before returning the unit to Kingwa) will be to change the firmware in my Dac (Sabre based) to allow a more jittery spdif stream.
 
Will let you know...
 
But consider that, based on my tests:
 
- Sabre Dac (Buffalo II Dac) + a very cheap USB->SPDIF convert = OK
 
- Audio GD Digital Interface + Monica2 Dac = OK
 
Tried on 4 different computer on 2 different locations on 3 different OS with a total of 6 different software players with 4 different spfif cables and 4 different usb cables.
 

 
All the best
 
AF
 
 
Quote:

@sfogar when did you buy your DI?  
 
I mean it could be power irregularities affecting the PC but the cyclical nature of the problem has me baffled - the ID, USB controller and NFB-10 are all running from a power regenerator which will filter out any power irregularities - but the PC power supply also has it's own DC voltage regulation circuitry which should [and has been measure to] fix any transient voltage irregularities (ie. no matter what voltage is being fed into the PC the PSU I have should put same voltage into 12V, 5V, 3V.)  Given this I think it's fair to say that my system is in theory immune to wall power anomalies.  I'm not sure how well the PSU fixes fast rise-time voltage irregularities - but I'm guessing the caps in the design should filter these out.  Either way I can get a PSU tester to check this next week, but again I seriously doubt that it is power supply related.
 
i wouldn't be suprised if all those affected by regular/cyclical dropout behavior bough DI's from the same batch/revision...
 
a friend of mine with same dropout problem has contacted Kingwa and he couldn't help.  Same guy has a NFB-10 ES fed from the same USB port which runs without dropouts (I think that also runs an adaptive USB implementation, probably TE7022 also.)  interesting huh.

 

 

[kr0gg]

please let us know about your DI's destiny after being shipped to Kingwa!

 

[borrego]

One last thing to try for "dropout" trouble shooting: Check if the memory modules inside your computer are matched in speed and latency timing. I have had unmatched memory modules in my notebook before and after I changed to another matched memory module, the number of dropouts reduced significantly.
 
May also try changing the latency/energy saving/PCI related parameters in the BIOS as last resort
 
 

 

[drez]

EDIT: there is no fixing this problem.  How irritating.  Both this DI and my NFB-10 have faulty operation.  Score

 
I ordered a BNC attenuator, not that I have any confidence that it will work.  Probably just wasted another $15 on this cursed box.
 
At this point I am fully committed to reviewing my experience with AGD gear.  Buy with confidence.

 

[kr0gg]

Quote:

 Buy with confidence.

uhm?

 

[haloxt]

Drez, have you tried multiple computers?

 

[drez]

I will tried to get wasapi/asio drivers no my laptop but it wouldn't install [the drivers.]  I will try again when I get some free time but honestly it shouldn't need THIS much work to get dropout free audio from a USB interface.  It's not like I'm building the thing.
 
But honestly if I do get bit-perfect streaming to work from another computer - I'm not going to change the computer I stream from long term - so apart from determining if the DI might work on another PC the results will be mostly superfluous.
 
In other words personally I don't care if this works perfectly on another computer - I'm not going to change my computer (any further that is) in order to get this thing to work.

 

[haloxt]

The thing is, if it's your computer's fault, you can't blame the DI or NFB-10. It may seem to you unlikely that it is your computer's fault, but it's important to find out if it is so that the appropriate measures can be taken. If you test with 3-4 computers with the same results, then it becomes likely the audio-gd gear is defective. If you don't test, we'll never know for sure.

 

[Gilst]

I've seen EMU 1212m mentioned in this thread.
 
I'm using EMU coax out ->Audio-GD DI coax In -> Buffalo32S ->.. and there's something very smooth in the sound, only apparent after a few seconds.
Comparing to straight USB ->DI -> Dac... (which sounds great as it is), involving the EMU card certainly adds something, may it be jitter reduction or some sort of filtering.
Perhaps anyone having this combination (EMU coax out -> DI -> Sabre DAC) could comment on the EMU impact on the sound?
 
I'm running a 48khz session into non-upsampling free of jumpers DI.
 
Thanks.
 

 

[somestranger26]

Have you tried USB -> Isolator -> DI?

 

[drez]

yes I have tried the isolator, doesn't fix the problem.
@haxlot you don't work for AGD do you?

I mean I get no dropouts when using direct sound, but that's not something I want to do.  
My colleague gets no dropouts when using the NFB-10 inbuilt adaptive USB interface (and probably the same te7022 chip.)  There are 3 of us all who bought the DI at around the same time who are having this problem, and collectively have still not found any computer system that works with out AGD DI without dropouts (with bitperfect streaming.)  Upsampling does mask the problem but we should not have to use such workarounds, esp. as I prefer the sound without upsampling.
As for my NFB-10 - it makes noise with low impedance phones even with no digital input plugged in, and when run through a PS-Audio style power regenerator, and tracks with the volume pot.  My colleague had the same problem, sent it back to AGD with a set of headphones for testing and they magically couldn't reproduce the problem and tried to blame it on wall power (which clearly is not the case.)  Either they don't know how to design a power supply, or have pretty bad QC and testing.
Needless to say if isolated factors were to blame for the dropouts would 3 of us (with completely different systems, different OS, different countries etc.) be having the same problems, spend months trying to fix it and still no results?  Either way I will test with my laptop this weekend but this is quite a lot of trouble I have gone to so far for what is supposedly a finished product.
 
or maybe AGD needs some schooling on how to design a USB interface (from John Kenny)

 

[borrego]

drez, if you still have drop-out problem with your DI running USB power, the issues may be caused by NFB-10 having inverted polarity power cable.
 
See here Pacific Valve is replacing ALL stock power cables for their Audio-gd product: http://pacificvalve.us/AudiogdGallery.html
 
So it could be the stock power cable of the NFB-10 is the source of all the problems.

 

[drez]

Could be - there is no way of knowing if the DI operates without dropouts when there is nothing plugged into it's output.
 
"If a tree falls in a forest and no one is around to hear it, does it make a sound?"

 
I will try a different PS cable anyway.  
 
EDIT: different PS cable does not fix issues with the NFB-10.  From what I hear the Australian power cables were not affected by this problem anyway.
 
again ouch

 

[jimmychan]

 
I have tried five computers and no drop out problem al all.

 

[borrego]

Quote:

Needless to say if isolated factors were to blame for the dropouts would 3 of us (with completely different systems, different OS, different countries etc.) be having the same problems, spend months trying to fix it and still no results?  Either way I will test with my laptop this weekend but this is quite a lot of trouble I have gone to so far for what is supposedly a finished product.
 
or maybe AGD needs some schooling on how to design a USB interface (from John Kenny)

If you have already tried the DI on different computers then there is 1 more thing to check: the USB socket of the DI, see if the USB cable is kind of loose when it is plugged in. On my DI the little spring tab inside the USB socket kind of give in and causes the USB cable plug loosen. Now I wrap the USB cable around the DI case and put duck taped the cable to the case, "fixing" the USB plug from the socket.
 
The DI has its flaw but it is a good design given its price. Through it I got better sound from my Yamaha DVD-S1800 player so I am satisfied. I once was tempted to buy the Audiophilleo 2, but just kind of hard to justify the 3 x cost, for the the possible level of further improvement. That is after I have improved the DI's sound by using the 74AHC04 chip.