ProtoDAC TDA1387 X8 project

[bobdcarr]

ProtoDAC can only handle 5V (5.5V max). You can use an LT1963 module to regulate down to 5V. The one problem with the LiPO is the higher ESR (internal resistance) compared to LifePO4 batteries. The LiPO don't sound as dynamic.

The Soviet K77-1 polycarbonate caps sound excellent. Just trying them now. Great value. Sound better than the used CRC 10uF 30V.

I use the LiitoKala Lii-202 .

Ok, thanks, I picked p a couple of those regs. Did you compare the Soviet caps to the Wika MKP4 (RED) ones?

[hifinet]

I will be comparing some different output coupling caps in the next few days. I think the polycarbonate caps in general are better sounding than the basic MKP (like the WIMA and Audiophiler). The Jantzen Superior Z-cap are also MKP, but they use a special winding technique, and they sound better than all the other caps I have listened to so far. I need to go back and compare them. They sound more forward in presentation, but that may resolve as they break in. They are very low loss throughout the range. The Jantzen are a lot more expensive. This is another one I am trying.

[theshepmatt]

I swapped from Wima MKP to Jantzen Superior Z-cap today, and the soundstage opens up even more, clarity and definition in the whole area. They are not that expensive either, £45,- for a pair at Hificollective. I also use the AudioNote Kaisei 2200uF on the powerside which also is a cheap upgrade. I'm really amazed by what this design can do - thank you so much!!

Hey mate, I've been getting my vishay resistors from Hifi Collective, could you share a link to the caps please, and the big gold fellow in the middle, I take it you cross it over the 4 holes, neg from 1 and pos with the other. And do those Janizen caps fit? they look massive!! Cheers Matt

[Ludomaniac]

I swapped from Wima MKP to Jantzen Superior Z-cap today, and the soundstage opens up even more, clarity and definition in the whole area. They are not that expensive either, £45,- for a pair at Hificollective. I also use the AudioNote Kaisei 2200uF on the powerside which also is a cheap upgrade. I'm really amazed by what this design can do - thank you so much!!

Hey mate, I've been getting my vishay resistors from Hifi Collective, could you share a link to the caps please, and the big gold fellow in the middle, I take it you cross it over the 4 holes, neg from 1 and pos with the other. And do those Janizen caps fit? they look massive!! Cheers Matt

Hi!

The one in the middle is the Audio Note Kaisei: https://www.hificollective.co.uk/catalog...f-16v.html
It is polar and can be connected to either C3 or C4 as one 2200uF replaces the two 1000uF suggested earlier.

The Jantzen Superior Z-cap is 4.7uF and here is the info for it: https://www.hificollective.co.uk/index.p...-9891.html

[DRONE7]

Heaven.
I have been in contact with Mark and he provided a couple of links for output caps value vs phase shift and following input impedance.
( I will let him add these)
I get it now!  Joyous experimenting with this ProtoDac.
There is this big triangle of output cap value, following input impedance,supply electrolytic value and then all the variations of the component quality.

Add to that the Pi versions and performance/access/connection and you have much to play and experiment with.

For years I have searched for a Digital Playback that would give me the thrill of my Well Tempered Classic - Koetsu Rosewood front end and the sound-stage height, width, life, and depth that that brings.  (yes, lots of set-up and ongoing tweaking) but especially height!

This ProtoDac , unlike any other digital device I have tried, does it for me !

Today for experimenting, using the very basic DIY version with 3.3uF output caps into pre-amp  input@47k.
3.3uF caps and 2x1000uF electrolytics.

Some years ago I bought a Philips CD player and when it died I harvested anything that could go in the parts bin.

So, I was using 2x Nichicon 1000uF electrolytic but replaced one with a Phillips from the cd of the same era as the module.
Such magic that, once run in, I will be trying 2 of them.

omg these Phillips caps have balls! and speed! air, dynamics,and coherence, (and all the subtlety too)
As they run in it gets better and better.

An Anthology of Sacred Carols for Classical Guitar
What Child Is This (Greensleeves)
James Sundquist

[hifinet]

The difference in sound quality with power supply and decoupling caps is very interesting. The IC PurePi 5V UC supply didn't have much height, for some reason, but it's super quiet and the deep bass is amazing. The Allo 5V 3A supply had a bigger soundstage, but it's noisy and the bass is not nearly as good. The LifePO4 seems a good compromise. I think the value of the decoupling caps changes things, too. These observations are on my system and may not translate to other systems. It's a slow process. The decoupling caps take 60+ hours to break in.

[Ludomaniac]

Anyone tried the IanCanada 3.3v and 5v extreme supercapacitors PSU on this one? I'd really like to hear some experiences...

[DRONE7]

Made an adapter board to feed the ProtoDac 5v separate supply and i2s from an AKM 4118 input switcher.

Fed it from Moode RPi> HiFiBerry Digi>AKM 4118>ProtoDac

Then from a Moode>NuForce USB to Spdif>AKM 4118>ProtoDac

Then from other Linux devices and OS..and will try Windows tomorrow.

Have a DIYinHK Xmos 216 to try and know this works very well from MoOde !
RPi>Moode>DIYinHK>XMOS>ProtoDac.

So many options...

[varunach]

I noticed that when using Camilla DSP, the output volume is lower in general. There is no gain attenuation anywhere in the pipeline so curious why this is the case. Even compared to the input volume, the output volume seems a few DBs lower (screen shot). I usually have to have my volume knob on my integrated amp at 4'o clock when using Moode + CamillaDSP whereas if i use the ALSA polarity inversion setting or feed the USB directly to my integrated DAC/amp i can listen at 2'o clock setting.

[Tim Curtis]

It's might be due to the difference in the volume curves used by MPD vs CamillaDSP.

I suppose a test would be to set moode volume at 100 (0dB) using both configurations and then see if the actual volume level heard is the same. Obviously set your Amp volume way down before doing this !!