Tír Na HiFi

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realisations so far
system clk seems to be 8mhz
must be a real time clock as theres a 32.768 khz crystal
the usual 22/24 mhz and both of them screaming away at the same time.. tut tut
seems to be two main regs of 8v into 5v and then to two 3.3v with a smd ldo
ill likely just tap in here for starters then lift the clocks then see about getting the i2s out closer to the chip

to start out i put on the bench variable linear lab supply and a 5102 dac chip of lifepo4
and initially it doesn't sound bad per se, smooth, low noise lacks detail and finesse but again stock on linear

I wish you the best with this.

Always fun joining in on the adventure of you turning the sow's ear into a silk purse.

Still think you might wish you went ahead got the one that is basically finished. But I know you love the challenge!

I will be using the time to finally build my 4P1L line stage which I hope will add some romance to my SD player. It could use a little something extra.

Meant to say yesterday - I wonder if both of these SD threads should be blended together under the heading of SD card based players?

rickmcinnis wrote:Meant to say yesterday - I wonder if both of these SD threads should be blended together under the heading of SD card based players?

think as there different best keep em separate?
not that im not interested in the sd trans i was just been cheap

neither sd player is built in a way that doesnt need mods,
so either of the boards are a starting point,
i have good clks here i can use
to me these players there just chips on a board and partial built

Its your choice, I thought it would make it easier on folks who are interested in the idea.

OK took off 3.3v regs put in a lifepo4 cell and connected the soekris
sounds good
seems to be less detail/resolution (maybe changing the clocks will fix) noise floor seems lower, bass is more robust
certainly looks like an option for digital audio

replaced the 22 mhz clock with the good ndk one
made a hell of a difference to detail retrieval

maybe some aspects of detail better than pc but more to come yet
have to find a good 8mhz clock

cant seem to see the 32.768khz on the crystal with the scope ?
dunno what thats about
i have good 32.768khz clocks here i was going to try but this is confusing me

That sure is a fancier display than the SDtrans. One wonders how much power it requires? Can you power it separately from the rest? I always delete that cover stuff from my files - eats up a fair amount of room. Maybe not as much when you have only 32gB total but with a 500gB SDD it can add up to a few recordings. I am surprised you would use that. Seems like all of that stuff would make the display work harder. Do these displays make noise? One wonders if there would be something gained by using a simpler display?

Is 8mHz an unusual value for this application? I can see advantages with such a slow clock - could it be akin to slowing down the CPU?

Why do you think they chose this value?

rickmcinnis wrote:
Is 8mHz an unusual value for this application? I can see advantages with such a slow clock - could it be akin to slowing down the CPU?

Why do you think they chose this value?

no idea why its 8mhz my board was built to price more so than anything else
however this gives much simplicity on which to build

the 8mhz clk has been changed now with an increase of resolution
and i think its worth demoing at next CA meet

nige2000 wrote:

rickmcinnis wrote:
Is 8mHz an unusual value for this application? I can see advantages with such a slow clock - could it be akin to slowing down the CPU?

Why do you think they chose this value?

no idea why its 8mhz my board was built to price more so than anything else
however this gives much simplicity on which to build

the 8mhz clk has been changed now with an increase of resolution
and i think its worth demoing at next CA meet

How does it compare to your PC now?
Because I'm also a cheap bastard, I'm thinking about buying one of these (instead of the deluxe model that Rick has)

And I agree with Rick about the display, I would worry that it adds noise to the system, would be nice if it could be isolated from the rest of the board, wonder how difficult it would be to do that.