Tír Na HiFi

jkeny wrote:

rickmcinnis wrote:....
ALL HAIL jkeny and his battery scheme!

Steady on there, Rick :)

always seemed strange to me that using battery power for these type of things isn't more common
as there is not any reg that could compete performance wise at this voltage at least not at any reasonable cost

nige2000 wrote:

jkeny wrote:

rickmcinnis wrote:....
ALL HAIL jkeny and his battery scheme!

Steady on there, Rick :)

always seemed strange to me that using battery power for these type of things isn't more common
as there is not any reg that could compete performance wise at this voltage at least not at any reasonable cost

Yep, with lifepo4 batteries, its relatively cheap and easy to make this a killer dac.

BTW, I guess I agree that the fpga cap mod was worth it, although for a while yesterday I was doubting it. I think there are a lot of changes that have made small improvements, but taken in total they add up to something special.

So you just pushed the caps? In the middle of the cap?
Unique capacitor test :)

I plan to get my usb chip working first, and then I'll try sychronized mode.

Randy

My enthusiasm can overshoot its boundaries when it is FULLY justified, jkeny!

Wish Randy had not thought the FPGA cap mod worth the trouble. Guess I will go ahead and order the caps and stare at them for a few weeks.

Wish the clock mod PCI-e card was not needed. I am powering whatever card is there with battery power through the ASROCK riser so the only thing missing will be the clock. When I install all of those caps I may be ready to do that. Might have enough confidence.

Does anybody make a PCB that would make installing the clock easier? Will start looking.

Nigel, do you know anything good or bad about the VIA USB chip? Like I said I am getting purely for troubleshooting. I know the slot works since I have put the video card in there. The riser is getting power. Strange that neither the SILVERSTONE or the JCAT card are recognized.

DIYINHY card is ordered.

Where is the next cliff for us to jump from?

rickmcinnis wrote: Wish Randy had not thought the FPGA cap mod worth the trouble. Guess I will go ahead and order the caps and stare at them for a few weeks.

lmao

Honestly, this one is borderline because the caps are so fragile. Although once I pulled the scope out, it was easy to find the bad ones and replace them.

I ordered 100 caps because you get a price break from Mouser there, and I'm glad I had the extra ones so I don't have to worry about running out.

Randy

[quote="rickmcinnis"
Wish Randy had not thought the FPGA cap mod worth the trouble. Guess I will go ahead and order the caps and stare at them for a few weeks.[/quote]
you could leave it til later its not plain sailing getting these fragile caps on, and there's much else to do

Wish the clock mod PCI-e card was not needed. I am powering whatever card is there with battery power through the ASROCK riser so the only thing missing will be the clock. When I install all of those caps I may be ready to do that. Might have enough confidence.

Does anybody make a PCB that would make installing the clock easier? Will start looking.

iancanada at diyaudio might have adapter boards for clks

Nigel, do you know anything good or bad about the VIA USB chip? Like I said I am getting purely for troubleshooting. I know the slot works since I have put the video card in there. The riser is getting power. Strange that neither the SILVERSTONE or the JCAT card are recognized.

i had a via card before i always prefered the renasas

DIYINHY card is ordered.

Where is the next cliff for us to jump from?

bypass fpga
no idea where to start though

Nah, there's no chance of bypassing the FPGA - it does a number of things specific to the Soekris configuration along with converting the I2S incoming signal into sign-magnitude output which is then directed to L & R channels & within these channels to +ve & -ve legs. It also controls the timing/clocking of these signals to each of the shift regs - they might be serial to each shift reg in the leg or parallel to all shift regs in each leg - only a logic analyser will give you this info. Latching of the parallel outputsall at the same tim eis also controlled by an FPGA signal.

This is probably as far as this design can be tweaked. To do any better would require a different approach which addresses the weak areas of the Soekris design.

jkeny wrote:Nah, there's no chance of bypassing the FPGA - it does a number of things specific to the Soekris configuration along with converting the I2S incoming signal into sign-magnitude output which is then directed to L & R channels & within these channels to +ve & -ve legs. It also controls the timing/clocking of these signals to each of the shift regs - they might be serial to each shift reg in the leg or parallel to all shift regs in each leg - only a logic analyser will give you this info. Latching of the parallel outputsall at the same tim eis also controlled by an FPGA signal.

This is probably as far as this design can be tweaked. To do any better would require a different approach which addresses the weak areas of the Soekris design.

so it would be as easy/difficult as starting a new design

if that's the case were probably not that far off all the soekris dac can be

was letting the sound of the current soekris implementation soak in over the wkend and it is rather impressive even with my desktop pc it is pretty immersive
so it is likely not as vulnerable to upstream and issues this is likely due to the usb hub and its clean power
however upstream issues still prevail and is obvious testing it on the audio pc, it seems there will never be a silver bullet

Forgive my laziness - are those FPGA caps 1608, like the resistors, or 2012s?

Sure hope they are the larger size ...

Thanks,

rickmcinnis wrote:Forgive my laziness - are those FPGA caps 1608, like the resistors, or 2012s?

Sure hope they are the larger size ...

Thanks,

think it was 0603 i put on them

Nigel,

The ROSEWILL PCI-e USB card ended up having the NEC chip instead of the VIA it said it would.

it did not work, either.

SO, you are not having any problems with an NEC card and XMOS? This is very strange. Cannot imagine the MB being the problem but nothing else would explain it. I know the slot works. I love my little MB!

Let me know when you can.

Thanks,