NOT QUITE NEVER AGAIN, THE GROUP BUY DAC BUILD

[gstew]

LOL... there's always something else to try. BUT one way I know a particular setup is working right is when I get wrapped up in the music and forget to notice the sonic qualities. I just finally applied the configuration tweaks recommended on Soundcheck's blog for RPi setups on picorePlayer on my recently installed Allo USBBridge Signatures (brilliant RPi substitutes with many individual linear regulators for all of the unit's rails, much associated filtering, and upgrades to the USB and Ethernet configurations to eliminate some of the built-in limiitataions of all of the RPi's up to version 4 and provide a quieter Ethernet input and a high-quality USB output for USB DACs... a nice upgrade from my linear-regulator modified RPi 2B). Sitting here listening to one, then my other setup after they warmed up and I'm just enjoying the music. A good sign!

Next big projects are to re-attack my Soekris setups and see if I can elevate them to this level. AND my Twisted Pear Buff-III Pro setups. AND my modified Sony HAP Z1-ES, which with PCM1795 DAC chips should respond well to many of the DDDAC and Nigel Group Buy DAC build mods/tweaks.

Later!

Greg in Mississippi

[tapatrick]

Its been a while since we posted an update on the build so here goes.

Very curious to hear how your project is going. Do you have any updates?

[Sligolad]

Very curious to hear how your project is going. Do you have any updates?

We have 5 of the DACs out in the wild and all getting great feedback, the sixth and final one is ready for delivery soon.
We have been working on solving some DAC chip failures through modifying grounds and also working on a delayed switch to direct Capacitor power feeds as switching on the DAC direct from Capacitor supply will blow the DAC chips.

Switching on the DAC with regulated supply and then switching over to Capacitors seems to solve all the issues with the DAC chips getting popped by the surge from the Capacitors.

The direct Capacitor supply with the regulated supply switched off gives a nice lift in sound quality so it is definitely the way to go to get the best out of the DAC.

For the SD Card end the best results will be found after bypassing the 5v in and feeding 3.3v supply to the SD Player.
Also taking off the on-board clocks and using better clocks will also give a good improvement.
After that you just need good SD cards (preferably an SLC card if you can afford one) and you are good to connect to any DAC you have with I2s In.

[tapatrick]

Very curious to hear how your project is going. Do you have any updates?

We have 5 of the DACs out in the wild and all getting great feedback, the sixth and final one is ready for delivery soon.
We have been working on solving some DAC chip failures through modifying grounds and also working on a delayed switch to direct Capacitor power feeds as switching on the DAC direct from Capacitor supply will blow the DAC chips.

Switching on the DAC with regulated supply and then switching over to Capacitors seems to solve all the issues with the DAC chips getting popped by the surge from the Capacitors.

The direct Capacitor supply with the regulated supply switched off gives a nice lift in sound quality so it is definitely the way to go to get the best out of the DAC.

For the SD Card end the best results will be found after bypassing the 5v in and feeding 3.3v supply to the SD Player.
Also taking off the on-board clocks and using better clocks will also give a good improvement.
After that you just need good SD cards (preferably an SLC card if you can afford one) and you are good to connect to any DAC you have with I2s In.

Great thanks for the updates and tips Pearse. Glad to hear it’s all going well.

I’ve got an SD card player running the past week, with the 5v reg bypassed. Waiting for clocks etc to come to do the other mods. I’ve dropped my other experiments - this is so good.


Sent from my iPhone using Tapatalk

[Sligolad]

Just another pointer if you are replacing clocks on the SD Player.

If you use good NDK clocks then you can mount them directly on the existing pads but you will have to solder very small wire extensions off the small NDK clocks to reach the larger pitch pads on the SD Card which requires a steady hand and lots of patience.

If you do go with external clocks with just a wire taken from the enable lines to fire up the 22 & 24 clocks you can run into issues with the SD Player not booting up....seems to be hit and miss getting this to work but if you persevere with grounds and maybe manual 3.3v enable you generally can get it to work.

We built some DACs with external NDK clocks on daughter boards which worked off the enable lines from the SD Player but they can be tricky to find a good reliable implementation.

I was using Crystek clocks recently and had to manually enable the 24 clock whenever i needed to listen to HiRez but that is almost never these days as Redbook files sound so good on this DAC.

I just changed over to the Andrea Mori Clocks group buy and builds from the diyAudio Forums.
These are SC Cut Laptek crystals with some small smd work on the boards but they are the best I have heard so far.
I will buy some more of these crystals when they become available.

The SD Card does not want to boot with the 3.3v enable connected on these clocks but I connect it after boot and it is fine...will work on finding a good implementation over the coming days if I can pull myself away from the music!!

I am feeding the board with a 5.7v directly off one of the supercapacitors and it sounds great. It will even work off 2 x 3.3v (6.6v) Lifepo4 batteries with no issues.

For now i will just run off the 22 Clock listening to redbook files...who needs HiRez or DSD when Redbook sounds so good on this DAC :-)

[tapatrick]

Just another pointer if you are replacing clocks on the SD Player....
For now i will just run off the 22 Clock listening to redbook files...who needs HiRez or DSD when Redbook sounds so good on this DAC :-)

Cheers Pearse that's great to know. I've got some NDKs on order, so I'll see how they go for first steps, think I'll order another SD card player. Is it worth pursuing the AMori or other clocks? I did look at them a while back to add to one of Ian Canada's reclocking boards..but now makes a lot more sense to clock the source than add ons and end points. I've got an Antipodes DXe for everyday roon streaming but the little SD card player out performs it for enjoyment.

Is that Ray LaMontage you are listening to..? :)

[Sligolad]

Is it worth pursuing the AMori or other clocks?

So far the improvement seems well worth it though there is a lot of work involved in sourcing all the parts and building the Clocks.
Best to start with the NDKs and take it from there as the onboard clocks you get with the board are pretty poor.

Is that Ray LaMontage you are listening to..? :)

It is indeed...well spotted.

[Sligolad]

Got the Andrea Mori Clocks 22 & 24 setup and running today off the 3.3v enable lines from the SD Player and they are working great with no issues booting the Card and switching between HiRez and Redbook tracks.
I am powering the Andrea Mori Clocks off a Supercapacitor 5.7v supply on the DAC and I will leave it permanent for a few days to let the clocks settle in and then add a switch for power later.

They are definitely worth the effort as they are by far the best clocks I have used yet, I have a set of Neutrino Super clocks which were powered off a 12v Paul Hynes SR7 supply and they were nowhere near as good, too much going on on those clock boards with regulators, isolators and pulse transformers.

[randytsuch]

I want to get some Mori clocks at his next group buy.
I only hear good things about the clocks, and really reasonable prices.

Did you get the oven too? Someone at diyaudio said he started without an oven, and it sounded great, but got even better when the oven to his crystal.

What type of crystal are you using?

Randy

[Sligolad]

Hi Randy,

I did what most did and just got the clocks and boards without the ovens not expecting what i heard.
I am now going after ovens like the rest of the guys seeing that you get another improvement with these.

I got the SC Cut crystals, 22, 24, 44, 48 crystals.
Further reading seemed to indicate the 22 & 24 are better for audio rather than dividing the 44 & 48 crystals.